U.S. patent application number 13/383370 was filed with the patent office on 2012-05-10 for power control system, power control method, power control device and power control program.
This patent application is currently assigned to PANASONIC CORPORATION. Invention is credited to Toshihisa Ikeda, Tetsuya Kouda, Kazunori Kurimoto, Naofumi Nakatani, Satoshi Tsujimura, Yasuo Yoshimura.
Application Number | 20120112696 13/383370 |
Document ID | / |
Family ID | 43449183 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120112696 |
Kind Code |
A1 |
Ikeda; Toshihisa ; et
al. |
May 10, 2012 |
POWER CONTROL SYSTEM, POWER CONTROL METHOD, POWER CONTROL DEVICE
AND POWER CONTROL PROGRAM
Abstract
Disclosed are a power control system, a power control method, a
power control device and a power control program, which can
efficiently supply power to an electric device and charge an
electric vehicle. A power control device (16) has: a second
communication unit (14) that receives charge information pertaining
to charging of an on-board battery (23) from an electric car (2)
prior to the arrival of the electric car (2) at a location where
power is supplied to the electric car (2); and a control
determination unit (11) that determines a power supply start time
of supplying power to an electric water heater (1) and a charging
start time of charging the on-board battery (23), on the basis of
the charge information, such that the supply of power to the
electric water heater (1) and the charging of the on-board battery
(23) are completed by a predetermined time.
Inventors: |
Ikeda; Toshihisa; (Kyoto,
JP) ; Yoshimura; Yasuo; (Shiga, JP) ;
Tsujimura; Satoshi; (Shiga, JP) ; Nakatani;
Naofumi; (Shiga, JP) ; Kouda; Tetsuya; (Osaka,
JP) ; Kurimoto; Kazunori; (Hyogo, JP) |
Assignee: |
PANASONIC CORPORATION
Kadoma-shi, Osaka
JP
|
Family ID: |
43449183 |
Appl. No.: |
13/383370 |
Filed: |
July 15, 2010 |
PCT Filed: |
July 15, 2010 |
PCT NO: |
PCT/JP2010/004593 |
371 Date: |
January 10, 2012 |
Current U.S.
Class: |
320/109 |
Current CPC
Class: |
Y02T 90/167 20130101;
B60L 11/1844 20130101; H02J 2310/12 20200101; Y02T 90/169 20130101;
Y04S 30/14 20130101; B60L 2250/14 20130101; B60L 2260/50 20130101;
H01M 10/48 20130101; B60L 53/63 20190201; B60L 53/665 20190201;
Y02T 90/168 20130101; Y02T 90/12 20130101; B60L 2240/62 20130101;
B60L 53/62 20190201; B60L 53/64 20190201; H02J 2310/64 20200101;
B60L 2240/622 20130101; Y02E 60/10 20130101; Y02T 90/16 20130101;
H02J 2310/48 20200101; Y02T 10/70 20130101; B60L 53/68 20190201;
B60L 53/11 20190201; H02J 7/007 20130101; H02J 3/14 20130101; H02J
2310/14 20200101; Y02T 10/72 20130101; Y04S 30/12 20130101; H01M
10/44 20130101; B60L 53/65 20190201; Y02T 90/14 20130101; B60L
53/14 20190201; B60L 2260/54 20130101; B60L 53/66 20190201; B60L
2240/70 20130101; Y02T 10/7072 20130101 |
Class at
Publication: |
320/109 |
International
Class: |
H02J 7/00 20060101
H02J007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 15, 2009 |
JP |
2009-166556 |
Jul 31, 2009 |
JP |
2009-178602 |
Aug 18, 2009 |
JP |
2009-188882 |
Claims
1. A power control system, comprising an electric vehicle and a
power control device that controls charging of a rechargeable
battery of the electric vehicle and controls supply of power to an
electric device, wherein the electric vehicle includes: the
rechargeable battery; a charge information acquiring unit that
acquires charge information pertaining to the charging of the
rechargeable battery; and a transmitter that transmits the charge
information acquired by the charge information acquiring unit,
prior to the arrival of the electric vehicle at a location where
power is supplied to the electric vehicle, and wherein the power
control device includes: a receiver that receives the charge
information transmitted by the transmitter, prior to the arrival of
the electric vehicle at the location where power is supplied to the
electric vehicle; and a power control unit that determines a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery, on the
basis of the charge information received by the receiver, such that
the supply of power to the electric device and the charging of the
rechargeable battery are completed by a predetermined time.
2. The power control system according to claim 1, wherein the
charge information includes a current remaining level of the
rechargeable battery, and the power control unit computes a time
frame required to charge the rechargeable battery, in accordance
with the current remaining level of the rechargeable battery, and
determines the power supply start time of supplying power to the
electric device and the charging start time of charging the
rechargeable battery, on the basis of the computed time frame
required to charge the rechargeable battery.
3. The power control system according to claim 1, wherein the
charge information includes information on a remaining level of the
rechargeable battery that is obtained at the time of vehicle
arrival at an installation location where the power control device
is installed, the remaining level being obtained based on a
distance between a current position of the electric vehicle and the
installation location, and the power control unit computes a time
frame required to charge the rechargeable battery, in accordance
with the remaining level of the rechargeable battery that is
obtained at the time of vehicle arrival at the installation
location, and determines the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery, on the basis of the computed
time frame required to charge the rechargeable battery.
4. The power control system according to claim 1, wherein the
charge information includes an estimated arrival time at which the
electric vehicle arrives at an installation location where the
power control device is installed, the estimated arrival time being
obtained based on a distance between a current position of the
electric vehicle and the installation location, and the power
control unit determines the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery, such that the charging start
time of charging the rechargeable battery follows the estimated
arrival time and such that a total power of a power required to
charge the rechargeable battery and a power used for operating the
electric device does not exceed a predetermined value.
5. The power control system according to claim 4, wherein the
charge information further includes information on a remaining
level of the rechargeable battery that is obtained at the time of
vehicle arrival at an installation location where the power control
device is installed, the remaining level being obtained based on a
distance between a current position of the electric vehicle and the
installation location, and the power control unit computes a time
frame required to charge the rechargeable battery, in accordance
with the remaining level of the rechargeable battery that is
obtained at the time of vehicle arrival at the installation
location, and determines the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery, on the basis of the computed
time frame required to charge the rechargeable battery and the
estimated arrival time.
6. The power control system according to claim 3, further
comprising: a server device that mediates communication between the
electric vehicle and the power control device, wherein the server
device includes: a distance information receiver that receives,
from the electric vehicle, the distance between the current
position of the electric vehicle and the installation location
where the power control device is installed; a remaining level
computing unit that computes the remaining level of the
rechargeable battery that is obtained at the time of vehicle
arrival at the installation location, on the basis of the distance
received by the distance information receiver; and a remaining
level transmitter that transmits the remaining level of the
rechargeable battery computed by the remaining level computing
unit, to the power control device.
7. The power control system according to claim 1, wherein the power
control device further includes an electricity rate information
storage unit that stores electricity rate information pertaining to
an electricity rate that varies according to time slots, and the
power control unit refers to the electricity rate information
stored in the electricity rate information storage unit, and
determines the power supply start time of supplying power to the
electric device and the charging start time of charging the
rechargeable battery, such that the charging of the rechargeable
battery is ended during a time slot in which the electricity rate
becomes equal to or lower than a predetermined rate.
8. The power control system according to claim 7, wherein the power
control unit starts charging the rechargeable battery after the end
of the supply of power to the electric device, and supplies power
to the electric device only during the time slot in which the
electricity rate becomes equal to or lower than the predetermined
rate, in a case where the power supply start time of supplying
power to the electric device does not fall within the time slot in
which the electricity rate becomes equal to or lower than the
predetermined rate.
9. The power control system according to claim 7, wherein the power
control unit starts charging the rechargeable battery after the end
of the supply of power to the electric device, and starts the
supply of power to the electric device in a time slot prior to the
time slot in which the electricity rate becomes equal to or lower
than the predetermined rate, in a case where the power supply start
time of supplying power to the electric device does not fall within
the time slot in which the electricity rate becomes equal to or
lower than the predetermined rate.
10. The power control system according to claim 7, wherein the
power control unit computes an electricity rate incurred when the
operation of the electric device is started prior to the charging
start time, and an electricity rate incurred when the operation of
the electric device is started after a charging ending time, on the
basis of the electricity rate information stored in the electricity
rate information storage unit, and then selects the lower
electricity rate out of the computed electricity rates.
11. The power control system according to claim 1, wherein the
electric device includes an electric water heater that boils water
and stores the boiled water.
12. A power control method for controlling charging of a
rechargeable battery of an electric vehicle, and controlling supply
of power to an electric device, the power control method
comprising: a charge information acquisition step of acquiring
charge information pertaining to the charging of the rechargeable
battery; a transmitting step of transmitting the charge information
acquired in the charge information acquisition step, prior to the
arrival of the electric vehicle at a location where power is
supplied to the electric vehicle; a receiving step of receiving the
charge information transmitted in the transmitting step; and a
power control step of determining a power supply start time of
supplying power to the electric device and a charging start time of
charging the rechargeable battery, on the basis of the charge
information received in the receiving step, such that the supply of
power to the electric device and the charging of the rechargeable
battery are completed by a predetermined time.
13. A power control device that controls charging of a rechargeable
battery of an electric vehicle and controls supply of power to an
electric device, the power control device comprising: a receiver
that receives charge information pertaining to the charging of the
rechargeable battery that is transmitted from the electric vehicle,
prior to the arrival of the electric vehicle at a location where
power is supplied to the electric vehicle; and a power control unit
that determines a power supply start time of supplying power to the
electric device and a charging start time of charging the
rechargeable battery, on the basis of the charge information
received by the receiver, such that the supply of power to the
electric device and the charging of the rechargeable battery are
completed by a predetermined time.
14. A non-transitory computer readable recording medium storing a
power control program that controls charging of a rechargeable
battery of an electric vehicle and controls supply of power to an
electric device, the power control program causing a computer to
function as at least: a receiver that receives charge information
pertaining to the charging of the rechargeable battery that is
transmitted from the electric vehicle, prior to the arrival of the
electric vehicle at a location where power is supplied to the
electric vehicle; and a power control unit that determines a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery, on the
basis of the charge information received by the receiver, such that
the supply of power to the electric device and the charging of the
rechargeable battery are completed by a predetermined time.
Description
TECHNICAL FIELD
[0001] The present invention relates to a power control system, a
power control method, a power control device and a power control
program for controlling charging of a rechargeable battery equipped
in an electric vehicle and controlling supply of power to an
electric device.
BACKGROUND ART
[0002] The use of a time-slot differentiated electricity rate
system for leveling the power demanded of a power supplier can
lower an electricity rate of a general household. For example, when
the time-slot differentiated electricity rate system is used, the
electricity rate is approximately 9 yen/kWh between 11 p.m. and 7
a.m., approximately 23 yen/kWh between 5 p.m. and 11 p.m. and
between 7 a.m. and 10 a.m., and approximately 28 to 33 yen/kWh
between 10 a.m. and 5 p.m.
[0003] The lowest electricity rate between 11 p.m. and 7 a.m. is
approximately 1/3 of the electricity rate obtained between 10 a.m.
and 5 p.m. In the present specification, information pertaining to
these power usage time slots and the electricity rates is referred
to as "time-slot differentiated electricity rate information".
[0004] Hereinafter, the time-slot differentiated electricity rate
information indicating the time slot between 11 p.m. and 7 a.m. is
described as a lowest electricity rate time slot.
[0005] Examples of an electric device that is operated in a
programmed manner in accordance with the lowest electricity rate
time slot (between 11 p.m. and 7 a.m.) include a storage type
electric water heater such as a heat pump water heater or an
electric boiler. The electric water heater boils water and stores
the boiled water during the lowest electricity rate time slot, and
allows the hot water to be consumed during daytime when the
electricity rate is the highest. The all-electric houses equipped
with this kind of storage type water heater have been increasing in
recent years.
[0006] Furthermore, in addition to the electric water heater,
examples of an electric device requiring a large amount of
electricity include heating and cooling equipment such as an air
conditioner, cooking equipment such as a rice cooker, and household
equipment such as a clothes washer, a clothes dryer and a dish
washer/dryer. A user of such an electric device operates the
equipment while being conscience of the lowest electricity rate
time slot or sets timers of the equipment so that the equipment
operate during the lowest electricity rate time slot.
[0007] Not only these electric devices but also energy storage
devices have been increasing. For example, a rechargeable battery
of an electric vehicle, a plug-in vehicle or a two-wheeled electric
vehicle can be charged at home. If there is a rechargeable battery
at home, excess power can be charged into the rechargeable battery,
and the rechargeable battery is discharged when power is needed.
The recent technical innovation and the rise of the oil prices
indicate that electric vehicles and two-wheeled electric vehicles
are becoming more popular. In most cases, on-board batteries of
electric vehicles and two-wheeled electric vehicles need to be
charged at home, which implies a definite increase in the number of
users who drive or wish to drive these vehicles in accordance with
the lowest electricity rate time slot.
[0008] On the other hand, an upper limit of a household power usage
is specified in a contract. Use of power exceeding the contract
power (allowable power) throws an ampere breaker serving the whole
house. Therefore, when the household equipment described above are
operated intensively during the period between 11 p.m. and 7 a.m.
producing the lowest electricity rate, the ampere breaker is likely
to be thrown in the middle of the night. If the user does not
notice that the ampere breaker is off, in the morning the user not
only sees the water not boiling or the rice not cooked in the
programmed rice cooker, but also cannot use his/her electric
vehicle because the rechargeable battery thereof is not
charged.
[0009] In other words, when intensively operating the household
equipment at night after setting the timers thereof, the user needs
to make sure that the amount of electricity consumed does not
exceed the allowable power.
[0010] The above has described examples of the use of electricity
in a general household. However, not only general households but
also business offices, factories and commercial facilities such as
stores that use various electric devices and electric transporting
vehicles have contract powers, which are the upper limits of
electricity usages, and are demanding to use the electric device
efficiently at low electricity rates within the range of the
contract powers.
[0011] There exists a conventional invention (see Patent Literature
1 and Patent Literature 2, for example) that performs control to
reduce the amount of power consumed in a charger in consideration
of the amount of power consumed in a house, so that the amount of
power consumed does not exceed a contract power or allowable power
when operating an electric device and charging a rechargeable
battery of an electric vehicle at the same time at night.
[0012] Patent Literature 1 describes an on-board battery charger
that reduces the amount of charging current used for charging a
home battery or an on-board battery, when the current exceeds a
contract current as a result of using a microwave. This on-board
battery charger controls the current immediately before the
contract power is exceeded, but does not systematically control the
current based on the current used by the microwave and the current
used for charging the batteries.
[0013] Patent Literature 2 describes a charging power management
system that creates a residential estimated power load map to
adjust the amount of power consumed between the beginning of
charging of an on-board battery and the end of the charging, so as
not to exceed a contract power.
[0014] Patent Literature 3 describes a charge control device and
method that are not for performing the control to prevent a breaker
from being thrown when electric devices are operated at the same
time as when a rechargeable battery of an electric vehicle is
charged, but for creating, in a car rental office where a plurality
of electric vehicles are charged, for example, a charging plan
based on a start time for using each vehicle and a necessary charge
amount required for each vehicle to reach its destination. This
technology uses a car navigation device for computing the start
time and the necessary charge amount required for each vehicle to
reach its destination.
[0015] However, according to the conventional methods, the
microwave or other electric devices that a user wishes to use
immediately is operated at the same time as when an electric device
such as a charger of an on-board battery is operated, which can be
used by the user any time. For this reason, during a period in
which the microwave is preferentially used, the amount of power
consumed for charging the on-board battery can be controlled to be
lower than the contract power. Because the abovementioned cooking
equipment is normally used in a relatively short period of time
(approximately several minutes to a little over ten minutes at the
longest), the amount of power consumed during this period can be
given up temporarily without causing any major adverse effects
where, for example, water is not boiled when needed or the electric
car does not move due to its weak battery. However, when using, at
home, an electric water heater that needs continuous supply of
power for a relatively long period of time and an electric car that
needs to be charged for a relatively long period of time, a time
period during which the power is supplied to the electric water
heater should not overlap with a time period during which an
on-board battery of the electric car is charged, so that these
equipment do not compete over the electricity.
[0016] It is obvious that the best way is to end the boiling
performed by the electric water heater and the charging of the
on-board battery within the lowest electricity rate time slot, but
this might cause a tremendous trouble when either one of the
equipment needs to be used preferentially to reduce the amount of
power consumed in the other. In other words, what is expected is
that the water in the electric water heater is not boiled when
needed, and therefore hot water is not available, or that the
battery of the electric car is not charged enough to be able to
drive it to the destination.
[0017] Moreover, the distance that the electric car travels varies
so significantly from day to day that the remaining level of the
on-board battery fluctuates at a charging start time point.
[0018] Needless to say, there are no problems if the remaining
level of the on-board battery is high. However, when the electric
car travels a significantly long distance and the remaining level
of the on-board battery is extremely low, uncertain situations
occur where a long charging time is required or larger current
charging needs to be performed, making a power control operation
extremely difficult. Particularly, even when the on-board battery
is charged after the electric water heater finishes boiling water,
the charging might not be ended fully by the next morning.
[0019] In the conventional power control operation that combines
the electric car and the microwave or other electric devices used
for a short period of time, there is a problem that cannot be
solved when combining an electric water heater and an electric car
that uses large current for a long period of time.
[0020] Because a rechargeable battery of an electric vehicle
basically cannot be charged while in use outside, except when the
rechargeable battery is charged quickly using a charging station,
it is preferred that the rechargeable battery be charged as much as
possible while the electric vehicle is at home or at work. Although
the conventional methods are effective in this case, there remains
a basic problem where the charging plan cannot be created until the
electric vehicle is connected to the charger at home.
[0021] In other words, the electric device is operated during the
lowest electricity rate time slot, not knowing when the electric
vehicle returns home. When the electric vehicle returns home during
the operation of the electric device, the charging plan that gives
the highest priority to charging of the electric vehicle needs to
be created, which in turn requires readjustment of the operation
for supplying power to the operating electric device or to electric
device planning to be operated.
[0022] For example, suppose that the electric vehicle returns home
around 11:30 p.m. when a clothes washer/dryer is used after 11 p.m.
during the lowest electricity rate time slot (11 p.m. to 7
a.m.).
[0023] When the operation of the clothes washer/dryer is stopped
until the electric vehicle is charged completely in order to
prioritize charging of the electric vehicle, the clothes are
immersed in detergent in the washer for several hours, which can
damage the clothes. Thus, the electric vehicle needs to be charged
after the operation of the clothes washer/dryer is ended.
[0024] Another example is an electric water heater that boils water
during the lowest electricity rate time slot. The boiled water is
stored in a storage tank. The storage tank is made to retain heat.
It is preferred that the electric water heater boil water
immediately before the obtained hot water is used. Therefore, the
water is boiled immediately before 7 a.m. so that the obtained hot
water can be used when setting the table for breakfast or washing
the dishes after the breakfast. Suppose that the electric water
heater is programmed to boil water around, for example, 5 a.m.
[0025] At this moment, suppose that the electric vehicle returns
home around 5 a.m. In order to use the electric vehicle at 8 a.m.,
charging of the electric vehicle is preferentially performed
immediately after the electric vehicle returns home. Meanwhile, the
boiling of the electric water heater is stopped until the charging
of the electric vehicle is ended. Then, the electric water heater
starts boiling the water as soon as the charging of the electric
vehicle is ended.
[0026] However, when the charging takes too much time and the
boiling does not end past 7 a.m., the hot water cannot be used for
setting the table for breakfast. In addition, there is a
possibility that a large amount of power is supplied to the
electric water heater after the lowest electricity rate time
slot.
[0027] In the prior arts, therefore, the charging plan that
prioritizes charging of the electric vehicle is created after the
electric vehicle returns home, and thus cannot be coordinated with
the operation of other electric devices, depending on when the
electric vehicle returns home.
CITATION LIST
Patent Literature
[0028] Patent Literature 1: Japanese Patent Application Publication
No. 2008-141924 (paragraphs 0015, 0028, FIG. 12)
[0029] Patent Literature 2: Japanese Patent Application Publication
No. 2008-136291 (FIG. 5)
[0030] Patent Literature 3: Japanese Patent Application Publication
No. 2009-136109 (paragraph 0050)
SUMMARY OF INVENTION
[0031] The present invention was contrived in order to solve the
problems described above. An object of the present invention is to
provide a power control system, a power control method, a power
control device and a power control program, which can efficiently
supply power to an electric device and charge an electric
vehicle.
[0032] A power control system according to one aspect of the
present invention is a power control system that has an electric
vehicle and a power control device that controls charging of a
rechargeable battery of the electric vehicle and controls supply of
power to an electric device, wherein the electric vehicle includes:
the rechargeable battery; a charge information acquiring unit that
acquires charge information pertaining to the charging of the
rechargeable battery; and a transmitter that transmits the charge
information acquired by the charge information acquiring unit,
prior to the arrival of the electric vehicle at a location where
power is supplied to the electric vehicle, and wherein the power
control device includes: a receiver that receives the charge
information transmitted by the transmitter, prior to the arrival of
the electric vehicle at the location where power is supplied to the
electric vehicle; and a power control unit that determines a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery, on the
basis of the charge information received by the receiver, such that
the supply of power to the electric device and the charging of the
rechargeable battery are completed by a predetermined time.
[0033] According to this configuration, the power control system
has an electric vehicle and a power control device that controls
charging of a rechargeable battery of the electric vehicle and
supply of power to an electric device. In the electric vehicle,
charge information pertaining to the charging of the rechargeable
battery is acquired, and the acquired charge information is
transmitted prior to the arrival of the electric vehicle at a
location where power is supplied to the electric vehicle. In the
power control device, the charge information transmitted by the
transmitter is received prior to the arrival of the electric
vehicle at the location where power is supplied to the electric
vehicle. On the basis of the received charge information, a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery are
determined such that the supply of power to the electric device and
the charging of the rechargeable battery are completed by a
predetermined time.
[0034] According to the present invention, because the power supply
start time of supplying power to the electric device and the
charging start time of charging the rechargeable battery are
determined such that the supply of power to the electric device and
the charging of the rechargeable battery are completed by the
predetermined time prior to the arrival of the electric vehicle at
the location where power is supplied to the electric vehicle, the
supply of power to the electric device and the charging of the
electric vehicle can be performed efficiently.
[0035] The above object, features and advantages of the present
invention will become clear from the following detailed
descriptions and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0036] FIG. 1 is a diagram showing an example of a configuration of
a power control system according to Embodiment 1 of the present
invention.
[0037] FIG. 2 is a first flowchart showing processes performed by a
control determination unit according to Embodiment 1 of the present
invention.
[0038] FIG. 3 is a second flowchart showing processes performed by
the control determination unit according to Embodiment 1 of the
present invention.
[0039] FIG. 4 is a diagram showing a relationship among time-slot
differentiated electricity rate information, consumed power, and
time frame, the relationship being obtained when a boiling time
slot of an electric water heater and a charging time slot of an
on-board battery fall within a lowest electricity rate power time
slot.
[0040] FIG. 5 is a diagram showing a relationship among the
time-slot differentiated electricity rate information, the consumed
power, and the time frame, which is obtained when economics are
given priority.
[0041] FIG. 6 is a diagram showing a relationship among the
time-slot differentiated electricity rate information, the consumed
power, and the time frame, which is obtained when convenience is
given priority.
[0042] FIG. 7 is a diagram showing an example of a configuration of
a power control system according to Embodiment 2 of the present
invention.
[0043] FIG. 8 is a diagram showing an example of a configuration of
a power control system according to Embodiment 3 of the present
invention.
[0044] FIG. 9 is a diagram showing a configuration of a server
device in FIG. 8.
[0045] FIG. 10 is a first flowchart showing processes performed by
a control determination unit 11 according to Embodiment 4 of the
present invention.
[0046] FIG. 11 is a second flowchart showing processes performed by
the control determination unit 11 according to Embodiment 4 of the
present invention.
[0047] FIG. 12 is a diagram showing an example of a boiling time
frame and a charging time frame according to Embodiment 4 of the
present invention.
[0048] FIG. 13 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is brought forward.
[0049] FIG. 14 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is brought forward and when boiling is performed outside the
lowest electricity rate time slot.
[0050] FIG. 15 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is segmented.
[0051] FIG. 16 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling is
performed after charging is done.
[0052] FIG. 17 is an overview showing an example of a configuration
of a power control system according to Embodiment 5 of the present
invention.
[0053] FIG. 18 is a block diagram showing an example of the
configuration of the power control system according to Embodiment 5
of the present invention.
[0054] FIG. 19 is a diagram showing an example of power usage of an
electric device according to Embodiment 5 of the present
invention.
[0055] FIG. 20 is a diagram showing an example of time-slot
differentiated electricity rate information according to Embodiment
5 of the present invention.
[0056] FIG. 21 is a diagram showing a charging sequence obtained
when a rechargeable battery is a lithium battery.
[0057] FIG. 22 is a flowchart for illustrating operations of the
electric device according to Embodiment 5 of the present
invention.
[0058] FIG. 23 is a diagram showing an example of priority orders
according to Embodiment 5 of the present invention.
[0059] FIG. 24A is a diagram showing an example of a control plan
obtained when a charging start time overlaps with an operating time
frame, FIG. 24B is a diagram showing an example of a control plan
obtained when a charging ending time overlaps with the operating
time frame, FIG. 24C is a diagram showing an example of a control
plan obtained when the operating time frame is shifted forward to
the front of the charging time frame, and FIG. 24D is a diagram
showing an example of a control plan obtained when the operating
time frame is shifted behind the charging time frame.
[0060] FIG. 25A is a diagram showing an example of a control plan
obtained when the operating time frame is shifted forward to the
front of the charging time frame, FIG. 25B is a diagram showing an
example of a control plan obtained when the operating time frame is
shifted behind the charging time frame, and FIG. 25C is a diagram
showing an example of a control plan obtained when operation of the
electric device is started at a start time of the lowest
electricity rate time slot and ended prior to the charging time
frame.
[0061] FIG. 26A is a diagram showing an example of a control plan
obtained when the operating time frame of the electric device
passes the lowest electricity rate time slot as a result of
shifting the operating time frame forward to the front of the
charging time frame, FIG. 26B is a diagram showing an example of a
control plan obtained after the operating time frame and the
charging time frame are shifted back from the state shown in FIG.
26A, and FIG. 26C is a diagram showing an example of a control plan
obtained when the operating time frame of the electric device is
segmented.
[0062] FIG. 27 is a first flowchart for illustrating a control plan
creation process of step S60 shown in FIG. 22.
[0063] FIG. 28 is a second flowchart for illustrating the control
plan creation process of step S60 shown in FIG. 22.
[0064] FIG. 29 is a diagram showing an example of an operating time
frame and a charging time frame according to Embodiment 5 of the
present invention.
[0065] FIG. 30 is a diagram showing an example of the operating
time frame and the charging time frame obtained when the operating
time frame is brought forward.
[0066] FIG. 31 is a diagram showing an example of the operating
time frame and the charging time frame obtained before the
operating time frame is brought backward.
[0067] FIG. 32 is a diagram showing an example of the operating
time frame and the charging time frame obtained after the operating
time frame is brought backward.
[0068] FIG. 33 is a diagram showing an example of the operating
time frame and the charging time frame obtained before the
operating time frame is brought forward.
[0069] FIG. 34 is a diagram showing an example of the operating
time frame and the charging time frame obtained after the operating
time frame is brought forward.
[0070] FIG. 35 is a diagram showing an example of the operating
time frame and the charging time frame obtained after the operating
time frame and the charging time frame are brought backward.
[0071] FIG. 36 is a diagram showing an example of the operating
time frame and the charging time frame obtained when a time frame
between a current time and an estimated return time is longer than
the operating time frame after the operating time frame is brought
forward.
[0072] FIG. 37 is a diagram showing an example of the operating
time frame and the charging time frame obtained when the time frame
between the current time and the estimated return time is equal to
or shorter than the operating time frame and when the operating
time frame is brought backward.
[0073] FIG. 38 is a block diagram showing an example of a
configuration of a power control system according to Embodiment 6
of the present invention.
DESCRIPTION OF EMBODIMENTS
[0074] Embodiments of the present invention are described
hereinafter with reference to the accompanying drawings. Note that
the following embodiments are merely illustrative and are not
intended to limit the technical scope of the present invention.
Embodiment 1
[0075] FIG. 1 is a diagram showing an example of a configuration of
a power control system according to Embodiment 1 of the present
invention. Embodiment 1 is described hereinafter with reference to
FIG. 1.
[0076] The power control system shown in FIG. 1 has an electric
water heater 1 and an electric car 2. The electric car 2 is an
example of the electric vehicle, which is moved by receiving supply
of power from a rechargeable battery equipped therein.
[0077] The electric car 2 is equipped with an on-board battery 23
for running a driving motor and an on-board electrical component, a
charge plug 24, a charge information detector 22, and a first
communication unit 21. The on-board battery 23 is charged by a
feeder 13 (described later) via the charge plug 24. The charge
information detector 22 acquires charge information pertaining to
charging of a rechargeable battery. The charge information detector
22 detects charge information including a current remaining level
of the on-board battery 23. The first communication unit 21
transmits the charge information acquired by the charge information
detector 22, prior to the arrival of the electric car 2 at a
location where power is supplied to the electric car 2. The first
communication unit 21 transmits at any time the charge information
detected by the charge information detector 22.
[0078] It is most preferred that a communication path of the first
communication unit 21 always or periodically communicate the charge
information pertaining to the remaining level of the on-board
battery 23 that changes every minute while the electric car 2
travels. The communication path is configured by, for example, a
mobile communication network (cell phone communication network, PHS
(Personal Handy-phone System) communication network, WiFi, WiMax,
etc.) capable of communication at all times or on a regular basis.
The charge information is eventually received by a second
communication unit 14 that is equipped in the electric water heater
1 installed inside a house, and imported to a control determination
unit 11.
[0079] The electric water heater 1 has a boiling unit 10, the
feeder 13, and a power control device 16. The boiling unit 10 boils
water and stores the boiled water in a hot water tank (not shown).
The feeder 13 supplies power to the on-board battery 23 via the
charge plug 24 to charge the on-board battery 23.
[0080] The power control device 16 has the control determination
unit 11, a clock 12, the second communication unit 14, a display
input unit 15, and an electricity rate information storage unit 17.
The clock 12 measures a time frame and outputs a current time. The
second communication unit 14 receives the charge information
transmitted by the first communication unit 21, prior to the
arrival of the electric car 2 at the location where power is
supplied to the electric car 2. The display input unit 15 displays
various information and accepts input from a user.
[0081] Based on the charge information received by the second
communication unit 14, the control determination unit 11 determines
a power supply start time of supplying power to the electric water
heater 1 and a charging start time of charging the on-board battery
23, such that the supply of power to the electric water heater I
and the charging of the on-board battery 23 are completed by a
predetermined time.
[0082] The control determination unit 11 plays a primary role in
this power control system and carries out a data computation
process and a determination process and controls each unit. The
charge information includes the current remaining level of the
on-board battery 23. In accordance with the remaining level of the
on-board battery 23, the control determination unit 11 computes a
time frame required to charge the on-board battery 23, and then
determines, on the basis of the computed time frame required to
charge the on-board battery 23, the power supply start time of
supplying power to the electric water heater 1 and the charging
start time of charging the on-board battery 23.
[0083] Specifically, the control determination unit 11 reads the
clock 12 and sends a boiling instruction to the boiling unit 10.
After sending a boiling discontinuation instruction to the boiling
unit 10, the control determination unit 11 controls the charging of
the on-board battery 23 by means of the feeder 13 and the charge
plug 24. Furthermore, the control determination unit 11 computes a
time frame required to charge the on-board battery 23, in
accordance with the remaining level thereof, computes a time frame
required for the electric water heater 1 to boil water (boiling
time frame), computes the amount of water that can be boiled per
fixed time frame, and computes an electricity rate for boiling the
water.
[0084] The electricity rate information storage unit 17 stores
time-slot differentiated electricity rate information pertaining to
an electricity rate that varies according to time slots. Based on
the time-slot differentiated electricity rate information, the
control determination unit 11 performs control such that the
boiling of water in the boiling unit 10 and the charging of the
on-board battery 23 are performed efficiently. The term
"efficiently" here implies not only that the control is performed
based on the time-slot differentiated electricity rate information
in order to obtain the lowest electricity rate, but also that
convenience is chosen over electricity rates in consideration of
the user's intention of accomplishing energy saving.
[0085] The time-slot differentiated electricity rate information,
which changes in accordance with the time slots and seasons, may
include time slots and rates that vary by contractors (households
or business offices). The time-slot differentiated electricity rate
information may also include time slots and rates that vary by
types of the electric device using the power (household electric
devices or industrial electric devices).
[0086] In addition, the control determination unit 11 starts
charging the on-board battery 23 after the supply of power to the
electric water heater 1 is ended. When the power supply start time
of supplying power to the electric water heater 1 does not fall
within a time slot in which an electricity rate becomes equal to or
lower than a predetermined rate, the control determination unit 11
supplies power to the electric water heater 1 only during the time
slot in which the electricity rate becomes equal to or lower than
the predetermined rate.
[0087] The control determination unit 11 also starts charging the
on-board battery 23 after the end of the supply of power to the
electric water heater 1. When the power supply start time of
supplying power to the electric water heater 1 does not fall within
the time slot in which the electricity rate becomes equal to or
lower than the predetermined rate, the control determination unit
11 supplies power to the electric water heater 1, starting from a
time slot prior to the time slot in which the electricity rate
becomes equal to or lower than the predetermined rate.
[0088] It should be noted in the present embodiment that the
electric car 2 corresponds to an example of the electric vehicle,
the on-board battery 23 to an example of the rechargeable battery,
the electric water heater 1 to an example of the electric device,
the power control device 16 to an example of the power control
device, the charge information detector 22 to an example of the
charge information acquiring unit, the first communication unit 21
to an example of the transmitter, the second communication unit 14
to an example of the receiver, the control determination unit 11 to
an example of the power control unit, and the electricity rate
information storage unit 17 to an example of the electricity rate
information storage unit.
[0089] Complicated processes performed by the control determination
unit 11 are described with reference to FIGS. 2 to 6.
[0090] FIGS. 2 and 3 are flowcharts showing the processes performed
by the control determination unit 11 in Embodiment 1 of the present
invention. FIG. 2 shows the processes performed when a boiling time
slot of the electric water heater 1 and a charging time slot of the
on-board battery 23 fall especially within a lowest electricity
rate power time slot that is shown in the time-slot differentiated
electricity rate information. FIG. 4 is a diagram showing a
relationship among the time-slot differentiated electricity rate
information, consumed power, and time frame, which is obtained when
the boiling time slot of the electric water heater 1 and the
charging time slot of the on-board battery 23 fall within the
lowest electricity rate power time slot.
[0091] First, the control determination unit 11 computes a time
frame required for the electric water heater 1 to boil water
(boiling time frame) (step S1). For example, the control
determination unit 11 previously stores a table in which the amount
of hot water to be stored and the boiling time frame are correlated
to each other, and computes the boiling time frame by acquiring the
amount of hot water to be stored, and extracting from the table the
boiling time frame corresponding to the acquired amount of hot
water to be stored.
[0092] Subsequently, the control determination unit 11 acquires
information (the charge information) pertaining to charging of the
on-board battery 23, via the second communication unit 14 (step
S2). The control determination unit 11 then acquires or computes a
time frame (charging time frame) required to charge the on-board
battery 23, on the basis of the acquired charge information (step
S3).
[0093] When the charge information includes the information
pertaining to the charging time frame, the control determination
unit 11 acquires the information pertaining to the charging time
frame from the second communication unit 14. When, on the other
hand, the charge information does not include the information
pertaining to the charging time frame but includes the information
pertaining to the remaining level of the on-board battery 23, the
control determination unit 11 computes the charging time frame
based on the remaining level of the battery. For example, the
control determination unit 11 previously stores a table in which
the remaining level of the battery and the charging time frame are
correlated to each other, and computes the charging time frame by
extracting from the table the charging time frame corresponding to
the acquired remaining level of the battery. In Embodiment 1, the
control determination unit 11 computes the charging time frame on
the basis of the current remaining level of the on-board battery
23.
[0094] Next, the control determination unit 11 computes a total
time frame by adding up the boiling time frame and the charging
time frame (step S4). The control determination unit 11 then
compares the obtained total time frame with the time-slot
differentiated electricity rate information (step S5).
[0095] Thereafter, the control determination unit 11 determines
whether the total time frame falls within the lowest electricity
rate power time slot (step S6). When it is determined that the
total time frame falls within the lowest electricity rate power
time slot (YES in step S6), the control determination unit 11
determines whether a current time acquired from the clock 12
reaches the lowest electricity rate time slot described in the
time-slot differentiated electricity rate information (step
S7).
[0096] When it is determined that the current time has not yet
reached the lowest electricity rate time slot (NO in step S7), the
control determination unit 11 returns to step S2 and carries out
the steps subsequent to step S2. In other words, the control
determination unit 11 repeats the steps S2 to S7 until the current
time reaches the lowest electricity rate time slot. Repeating the
steps subsequent to step S2 allows the control determination unit
11 to constantly deal with the latest information on the on-board
battery 23.
[0097] On the other hand, when it is determined that the current
time acquired from the clock 12 reaches the lowest electricity rate
time slot described in the time-slot differentiated electricity
rate information (YES in step S7), the control determination unit
11 instructs the boiling unit 10 to start boiling water (step S8).
Next, the control determination unit 11 determines whether the
boiling of the boiling unit 10 is ended or not (step S9). When it
is determined that the boiling is not yet ended (NO in step S9),
the boiling is continued until the end thereof.
[0098] When, on the other hand, it is determined that the boiling
is ended (YES in step S9), the control determination unit 11
instructs the feeder 13 to start charging the on-board battery 23
(step S10). Subsequently, the control determination unit 11
determines whether the charging of the on-board battery 23 is ended
or not (step S11). When it is determined that the charging of the
on-board battery 23 is not yet ended (NO in step S11), the feeder
13 continues to charge the on-board battery 23 until the end
thereof. When it is determined that the charging of the on-board
battery 23 is ended (YES in step S11), the control determination
unit 11 ends the series of boiling and battery charging
processes.
[0099] The above description has focused on the case in which the
total time frame, obtained by adding up the boiling time frame and
the charging time frame, is compared with the time-slot
differentiated electricity rate information and then certainly
falls within the lowest electricity rate power time slot. FIG. 4
shows the relationship among a boiling time period, an on-board
battery charging time period, and the time-slot differentiated
electricity rate information, which is obtained when the total time
frame of the boiling time frame and the charging time frame falls
within the lowest electricity rate power time slot. In FIG. 4, both
the boiling time period and the charging time period fall within
the power time slot producing the lowest electricity rate of 9
yen/KWH, which means that the boiling and the charging are
completed successfully without having the consumed electricity
exceed a marginal power or without having the breaker off.
[0100] In actuality, however, when the electric car 2 travels a
longer distance and the total time frame obtained by adding up the
boiling time frame and the charging frame is compared with the
time-slot differentiated electricity rate information, the total
time frame might not fall within the lowest electricity rate power
time slot. In this case, step S12 shown in FIG. 3 is performed
subsequent to the determination condition of step S6.
[0101] FIG. 3 shows details of processes that are performed when it
is determined that the total time frame obtained in step S6 of FIG.
2 does not fall within the lowest electricity rate power time slot.
FIG. 3 shows a flow of processes performed when the boiling time
frame and the charging time frame for charging the on-board battery
do not fall especially within the lowest electricity rate power
time slot described in the time-slot differentiated electricity
rate information.
[0102] FIG. 5 is a diagram showing a relationship among the
time-slot differentiated electricity rate information, the consumed
power, and the time frame, which is obtained when economics are
given priority. FIG. 6 is a diagram showing a relationship among
the time-slot differentiated electricity rate information, the
consumed power, and the time frame, which is obtained when
convenience is given priority.
[0103] When, in step S6 shown in FIG. 2, it is determined that the
total time frame does not fall within the lowest electricity rate
power time slot (NO in step S6), the control determination unit 11
causes the user to use the display input unit 15 to choose either
to give priority to economics or to give priority to convenience
over economics (step S12 in FIG. 3). However, when performing
display input, the user is not necessarily present in the vicinity
of the electric water heater 1. Thus, the user can choose to give
priority to either economics or convenience in advance. In this
case, no operation is performed to prompt the user to display or
input using the display input unit 15, and therefore step S12 is
skipped. At this moment, the control determination unit 11
previously causes the user to use the display input unit 15 to
prioritize either economics or convenience, and stores information
indicating the selected priority.
[0104] Next, the control determination unit 11 determines whether
economics are given priority or not (step S13). FIGS. 3 and 5 are
now used to describe a case in which the user chooses to prioritize
economics over convenience in step S13.
[0105] When it is determined that the user gives priority to
economics, or when the user chooses to give priority to economics
(YES in step S13), the control determination unit 11 reduces the
amount of water to be boiled and computes the reduced amount of
water to be boiled and the electricity rate incurred to boil the
reduced amount of water to be boiled, so that the total time frame
falls within the lowest electricity rate power time slot (step
S14). In other words, the control determination unit 11 computes
the amount of water that can be boiled within a remaining time
frame that is obtained by subtracting the charging time frame of
the on-board battery 23 from the lowest electricity rate power time
slot.
[0106] Subsequently, the control determination unit 11 displays, on
the display input unit 15, the reduced amount of water to be boiled
and the electricity rate incurred to boil the reduced amount of
water to be boiled, and asks the user to accept these displayed
inputs (step S15). However, because the user is not necessarily
present in the vicinity of the electric water heater 1 in this case
as well, the user can accept these inputs in advance. In such a
case, no operation is performed to prompt the user to display or
input using the display input unit 15, and therefore step S15 is
skipped. At this moment, when the reduced amount of water to be
boiled and the electricity rate incurred to boil the reduced amount
of water to be boiled are computed, the control determination unit
11 causes the user to use the display input unit 15 to previously
choose whether or not to accept the reduced amount of water to be
boiled and the electricity rate incurred to boil the reduced amount
of water to be boiled, and then stores information indicating the
resultant acceptance or rejection.
[0107] The control determination unit 11 then determines whether
the current time acquired from the clock 12 reaches the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information (step S17). Here, when
it is determined that the current time has not yet reached the
lowest electricity rate time slot (NO in step S17), the control
determination unit 11 returns to step S2 and carries out the steps
subsequent to step S2.
[0108] When, on the other hand, it is determined that the current
time reaches the lowest electricity rate time slot (YES in step
S17), the control determination unit 11 instructs the boiling unit
10 to start boiling the reduced amount of water to be boiled (step
S18). The control determination unit 11 then determines whether the
boiling is ended or not (step S19). When it is determined that the
boiling is not yet ended (NO in step S19), the boiling is continued
until the end thereof.
[0109] When it is determined that the boiling is ended (YES in step
S19), the control determination unit 11 instructs the feeder 13 to
start charging the on-board battery 23 (step S20). Subsequently,
the control determination unit 11 determines whether the charging
of the on-board battery 23 is ended or not (step S21). When it is
determined that the charging of the on-board battery 23 is not yet
ended (NO in step S21), the feeder 13 continues to charge the
on-board battery 23 until the end thereof. When it is determined
that the charging of the on-board battery 23 is ended (YES in step
S21), the control determination unit 11 ends the series of boiling
and battery charging processes.
[0110] FIG. 5 is a diagram showing the relationship among the
time-slot differentiated electricity rate information, the boiling
time period, and the charging time period for charging the on-board
battery 23, the relationship being obtained when economics are
given priority. In this case, because the reduced amount of water
is boiled, both the boiling time period and the charging time
period fall within the lowest electricity rate time slot described
in the time-slot differentiated electricity rate information.
[0111] Next, FIGS. 3 and 6 are used for describing a case in which
the user chooses to prioritize convenience over economics in step
S13.
[0112] When it is determined that the user chooses not to
prioritize economics, or when the user chooses to give priority to
convenience (NO in step S13), the control determination unit 11
computes a boiling start time for boiling the entire amount of
water, instead of keeping the total time frame of the boiling time
frame and the charging time frame within the lowest electricity
rate power time slot (step S22). At this moment, the control
determination unit 11 computes the boiling start time as a time at
which the boiling time frame starts, which is obtained when the end
of the charging time frame in which the charging is performed
subsequent to the boiling, matches an ending time of the lowest
electricity rate power time slot.
[0113] Next, the control determination unit 11 determines whether
the current time acquired from the clock 12 reaches the boiling
start time or not (step S23). When it is determined that the
current time has not yet reached the boiling start time (NO in step
S23), the control determination unit 11 returns to step S2 and
carries out the steps subsequent to step S2. As described above,
repeating the steps subsequent to step S2 of FIG. 2 allows the
control determination unit 11 to constantly deal with the latest
information on the on-board battery 23.
[0114] When it is determined that the current time reaches the
boiling start time (YES in step S23), the control determination
unit 11 instructs the boiling unit 10 to start boiling the entire
amount of water that is not reduced in amount (step S24).
Thereafter, steps S19 to S21 are performed.
[0115] FIG. 6 shows the relationship among the time-slot
differentiated electricity rate information, the boiling time
period, and the charging time period for charging the on-board
battery, the relationship being obtained when convenience is given
priority and the entire amount of water is boiled outside the
lowest electricity rate power time slot. In this case, as shown in
the diagram, the boiling is started before the start of the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information, in order to boil the
entire amount of water without reducing it, and then boiling the
entire amount of water and charging the on-board battery 23 are
ended.
[0116] As described above, because the boiling start time of the
electric water heater 1 is brought forward in accordance with the
remaining level of the on-board battery 23, it is possible to avoid
the inconvenience in which the water in the electric water heater 1
is not yet boiled even after the lowest electricity rate time slot.
It is also possible to avoid the inconvenience in which the
on-board battery 23 is not charged enough that the electric car 2
cannot be moved or reach a destination.
[0117] The control determination unit 11 can perform control to
allow the user to prioritize reduction of the electric rate or to
prioritize convenience over reduction of the electric rate. This
can clearly reflect the user's intentions of accomplishing energy
saving.
[0118] The above has described the control performed so as to
always keep the charging of the on-board battery 23 within the
lowest electricity rate time slot described in the time-slot
differentiated electricity rate information. However, in actuality,
this control might not be enough. For instance, when the electric
car 2 is used before the lowest electricity rate time slot
described in the time-slot differentiated electricity rate
information ends, the on-board battery 23 might not be charged
enough that the electric car 2 cannot be used. In this case, a time
at which the charging should be ended is input through the display
input unit 15, and then the control determination unit 11 performs
the above-described operations using the time at which the charging
should be ended, instead of using the ending time of the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information. Accordingly, the
control determination unit 11 can be caused to perform the same
operations as those described above, achieving the effects same as
or better than those described above.
[0119] Moreover, the above has described the basic conditions where
the on-board battery 23 is charged fully due to its
characteristics, but this charging method is not necessarily
preferred in terms of energy saving. For example, the user may
predict a distance that the electric car 2 travels the following
day (or a charge amount corresponding to the travel distance),
input the following day's travel distance (or the charge amount
corresponding to the travel distance) by using the display input
unit 15, and then charge the on-board battery 23 to a required
level without charging it fully every time. This can reduce the
amount of time required to charge the battery, and both the boiling
and the charging can be ended within the lowest electricity rate
time slot described in the time-slot differentiated electricity
rate information.
[0120] Moreover, in the present embodiment, it is most preferred
that the first communication unit 21 communicate, at all times or
on a regular basis, the information pertaining to the remaining
level of the on-board battery 23 that changes every minute while
the electric car 2 travels. The electric car 2 does not have to be
in a travelling state to perform the communication and no problem
arises to communicate the information while the electric car 2 is
parked. The first communication unit 21 may also communicate the
information when the electric car 2 is started up (when getting on
the car) or when the electric car 2 is stopped (when getting off
the car).
[0121] Needless to say, it is assumed that the electric car 2 has a
car navigation device. In this case, the first communication unit
21 transmits, to the electric water heater 1 at home, the charge
information including positional information acquired by a GPS
(Global Positioning System) equipped in the car navigation device.
The control determination unit 11 may compute a distance between
the house (the electric water heater 1) and the electric car 2 to
estimate a charge amount to be consumed by the on-board battery 23
until the electric car 2 returns home, and a time frame required to
charge the on-board battery 23, and then adjust the boiling start
time of the electric water heater 1 in consideration of the
estimated charging time frame.
[0122] The above has described the competition between the electric
water heater 1 and the on-board battery 23 over the power. However,
the same control operations as those described above can be
performed to achieve the same effects, not only in this competition
but also in a competition between the on-board battery 23 and the
electric device (e.g., a washer/dryer, a dish washer, etc.) that
can be operated during the lowest electricity rate time slot
described in the time-slot differentiated electricity rate
information.
[0123] The above has also described the example in which the
electric water heater 1 is used as the electric device, but the
electric device may be an electric boiler that boils water by using
electric heat only.
Embodiment 2
[0124] FIG. 7 is a diagram showing an example of a configuration of
a power control system according to Embodiment 2 of the present
invention. Embodiment 2 is described hereinafter with reference to
FIG. 7.
[0125] The power control system shown in FIG. 7 has the electric
water heater 1 and the electric car 2. The descriptions of the
configurations according to Embodiment 2 that are the same as those
of Embodiment 1 are omitted.
[0126] The electric car 2 is equipped with the on-board battery 23
for running a driving motor and an on-board electrical component,
the charge plug 24, the charge information detector 22, the first
communication unit 21, and an on-board navigation device 25. The
on-board battery 23 is charged by the feeder 13 (described later)
via the charge plug 24. The on-board navigation device 25 acquires
information on a current position of the electric car 2 and
provides information pertaining to a distance between the current
position and the house. Note that the house is an example of a
location where the electric water heater 1 (the power control
device 16) is installed.
[0127] The charge information detector 22 acquires charge
information pertaining to charging of the rechargeable battery. The
charge information detector 22 also acquires, from the on-board
navigation device 25, information pertaining to a current remaining
level of the on-board battery 23 and the information pertaining to
the distance between the current position of the electric car 2 and
the house.
[0128] Based on the acquired information pertaining to the current
remaining level of the on-board battery 23 and the acquired
information pertaining to the distance between the current position
and the house, the charge information detector 22 computes the
remaining level of the on-board battery 23 that is obtained at the
time of arrival at the house. More specifically, based on the
acquired information pertaining to the distance between the current
position and the house, the charge information detector 22 computes
the amount of power that is consumed by the on-board battery 23
until the time of arrival at the house. The charge information
detector 22 computes the remaining level of the on-board battery 23
obtained at the time of arrival at the house, by subtracting the
computed amount of power that is consumed by the on-board battery
23 until the time of arrival at the house, from the acquired
current remaining level of the on-board battery 23.
[0129] The first communication unit 21 transmits the charge
information acquired by the charge information detector 22, prior
to the arrival of the electric car 2 at a location where power is
supplied to the electric car 2. The first communication unit 21
transmits at any time the charge information that includes the
remaining level of the on-board battery 23 that is obtained at the
time of arrival at the house, the charge information being detected
by the charge information detector 22.
[0130] It is assumed that the communication path of the first
communication unit 21 is configured by a mobile communication
network such as a cell phone communication network, PHS
communication network, WiFi, and WiMax. The charge information is
eventually received by the second communication unit 14 that is
equipped in the electric water heater 1 installed inside the house,
and imported to the control determination unit 11.
[0131] Several methods are considered to compute the amount of
power that is consumed by the on-board battery 23 at the time of
arrival at the house. For example, the charge information detector
22 may register an average amount of power consumption per
kilometer in advance required for the electric car 2 and later
compute the amount of power consumed by the on-board battery 23 by
the time the electric car 2 arrives home by multiplying the
distance between the current position and the house by the above
average amount of power consumption per kilometer. The charge
information detector 22 may also compute an amount of power
consumed per kilometer, based on a travel status of that day, and
then compute the amount of power that is consumed by the on-board
battery 23 until the time of arrival at the house, by multiplying
the distance between the current position and the house by the
computed amount of power consumed per kilometer.
[0132] The power control device 16 has the control determination
unit 11, the clock 12, the second communication unit 14, the
display input unit 15, and the electricity rate information storage
unit 17. The control determination unit 11 plays a primary role in
this power control system and carries out a data computation
process and a determination process and controls each unit. The
charge information includes the information on the remaining level
of the on-board battery 23 that is obtained at the time of arrival
at the house, the remaining level being obtained based on the
distance between the current position of the electric car 2 and the
location where the power control device 16 is installed (e.g., the
house). The control determination unit 11 computes a time frame
required to charge the on-board battery 23, in accordance with the
remaining level of on-board battery 23 that is obtained at the time
of arrival at the house, and determines the power supply start time
of supplying power to the electric water heater 1 and the charging
start time of charging the on-board battery 23, on the basis of the
computed time frame required to charge the on-board battery 23.
[0133] More specifically, the control determination unit 11 reads
the clock 12 and sends a boiling instruction to the boiling unit
10. After sending a boiling discontinuation instruction to the
boiling unit 10, the control determination unit 11 controls the
charging of the on-board battery 23 by means of the feeder 13 and
the charge plug 24. Furthermore, the control determination unit 11
computes a time frame required to charge the on-board battery 23,
in accordance with the remaining level thereof, computes a time
frame required for the electric water heater 1 to boil water (the
boiling time frame), computes the amount of water that can be
boiled per fixed time frame, and computes an electricity rate for
boiling the water.
[0134] The electricity rate information storage unit 17 stores
time-slot differentiated electricity rate information pertaining to
electricity rates that vary according to time slots. Based on the
time-slot differentiated electricity rate information, the control
determination unit 11 performs control such that the boiling of
water in the boiling unit 10 and the charging of the on-board
battery 23 are performed efficiently. The term "efficiently" here
implies not only that the control is performed based on the
time-slot differentiated electricity rate information in order to
obtain the lowest electricity rate, but also that convenience is
chosen over electricity rates in consideration of the user's
intention of accomplishing energy saving.
[0135] Moreover, the control determination unit 11 refers to the
time-slot differentiated electricity rate information stored in the
electricity rate information storage unit 17, to determine the
power supply start time of supplying power to the electric water
heater 1 and the charging start time of charging the on-board
battery 23, such that the charging of the on-board battery 23 is
ended during a time slot in which an electricity rate becomes equal
to or lower than a predetermined rate.
[0136] It should be noted in the present embodiment that the
electric car 2 corresponds to an example of the electric vehicle,
the on-board battery 23 to an example of the rechargeable battery,
the electric water heater 1 to an example of the electric device,
the power control device 16 to an example of the power control
device, the charge information detector 22 to an example of the
charge information acquiring unit, the first communication unit 21
to an example of the transmitter, the second communication unit 14
to an example of the receiver, the control determination unit 11 to
an example of the power control unit, and the electricity rate
information storage unit 17 to an example of the electricity rate
information storage unit.
[0137] Complicated processes performed by the control determination
unit 11 are described with reference to FIGS. 2 to 6. The processes
performed by the control determination unit 11 in Embodiment 2 are
described with reference to FIGS. 2 to 6 of Embodiment 1.
[0138] First, the control determination unit 11 computes a time
frame required for the electric water heater 1 to boil water
(boiling time frame) (step S1). Subsequently, the control
determination unit 11 acquires information (the charge information)
pertaining to charging of the on-board battery 23, via the second
communication unit 14 (step S2). The control determination unit 11
then acquires or computes a time frame (charging time frame)
required to charge the on-board battery 23, on the basis of the
acquired charge information (step S3).
[0139] When the charge information includes the information
pertaining to the charging time frame, the control determination
unit 11 acquires the information pertaining to the charging time
frame from the second communication unit 14. When, on the other
hand, the charge information does not include the information
pertaining to the charging time frame but includes the information
pertaining to the remaining level of the on-board battery 23, the
control determination unit 11 computes the charging time frame
based on the remaining level of the battery 23. For example, the
control determination unit 11 previously stores a table in which
the remaining level of the battery and the charging time frame are
correlated to each other, and computes the charging time frame by
extracting from the table the charging time frame corresponding to
the acquired remaining level of the battery. In Embodiment 2, the
control determination unit 11 computes the charging time frame on
the basis of the remaining level of the on-board battery 23 that is
obtained at the time of arrival at the house.
[0140] Next, the control determination unit 11 computes a total
time frame by adding up the boiling time frame and the charging
time frame (step S4). The control determination unit 11 then
compares the obtained total time frame with the time-slot
differentiated electricity rate information (step S5).
[0141] Thereafter, the control determination unit 11 determines
whether the total time frame falls within the lowest electricity
rate power time slot (step S6). When it is determined that the
total time frame falls within the lowest electricity rate power
time slot (YES in step S6), the control determination unit 11
determines whether a current time acquired from the clock 12
reaches the lowest electricity rate time slot described in the
time-slot differentiated electricity rate information (step
S7).
[0142] When it is determined that the current time has not yet
reached the lowest electricity rate time slot (NO in step S7), the
control determination unit 11 returns to step S2 and carries out
the steps subsequent to step S2. In other words, the control
determination unit 11 repeats the steps S2 to S7 until the current
time reaches the lowest electricity rate time slot. Repeating the
steps subsequent to step S2 allows the control determination unit
11 to constantly deal with the latest information on the on-board
battery 23.
[0143] On the other hand, when it is determined that the current
time acquired from the clock 12 reaches the lowest electricity rate
time slot described in the time-slot differentiated electricity
rate information (YES in step S7), the control determination unit
11 instructs the boiling unit 10 to start boiling water (step S8).
Next, the control determination unit 11 determines whether the
boiling of the boiling unit 10 is ended or not (step S9). When it
is determined that the boiling is not yet ended (NO in step S9),
the boiling is continued until the end thereof.
[0144] When, on the other hand, it is determined that the boiling
is ended (YES in step S9), the control determination unit 11
instructs the feeder 13 to start charging the on-board battery 23
(step S10). Subsequently, the control determination unit 11
determines whether the charging of the on-board battery 23 is ended
or not (step S11). When it is determined that the charging of the
on-board battery 23 is not yet ended (NO in step S11), the feeder
13 continues to charge the on-board battery 23 until the end
thereof. When it is determined that the charging of the on-board
battery 23 is ended (YES in step S11), the control determination
unit 11 ends the series of boiling and battery charging
processes.
[0145] The above description has focused on the case in which the
total time frame, obtained by adding up the boiling time frame and
the charging time frame, is compared with the time-slot
differentiated electricity rate information and then certainly
falls within the lowest electricity rate power time slot. FIG. 4
shows the relationship among the boiling time period, the on-board
battery charging time period, and the time-slot differentiated
electricity rate information, which is obtained when the total time
frame of the boiling time frame and the charging time frame falls
within the lowest electricity rate power time slot. In FIG. 4, both
the boiling time period and the charging time period fall within
the power time slot producing the lowest electricity rate of 9
yen/KWH, which means that the boiling and the charging are
completed successfully without having the consumed electricity
exceed the marginal power or without having the breaker off.
[0146] In actuality, however, when the electric car 2 travels a
longer distance and the total time frame obtained by adding up the
boiling time frame and the charging frame is compared with the
time-slot differentiated electricity rate information, the total
time frame might not fall within the lowest electricity rate power
time slot. In this case, step S12 shown in FIG. 3 is performed
subsequent to the determination condition of step S6.
[0147] When, in step S6 shown in FIG. 2, it is determined that the
total time frame does not fall within the lowest electricity rate
power time slot (NO in step S6), the control determination unit 11
causes the user to use the display input unit 15 to choose either
to give priority to economics or to give priority to convenience
over economics (step S12 in FIG. 3). However, when performing
display input, the user is not necessarily present in the vicinity
of the electric water heater 1. Thus, the user can choose to give
priority to either economics or convenience in advance. In this
case, no operation is performed to prompt the user to display or
input using the display input unit 15, and therefore step S12 is
skipped. At this moment, the control determination unit 11
previously causes the user to use the display input unit 15 to
prioritize either economics or convenience, and stores information
indicating the selected priority.
[0148] Next, the control determination unit 11 determines whether
economics are given priority or not (step S13). FIGS. 3 and 5 are
now used to describe a case in which the user chooses to give
priority to economics over convenience in step S13.
[0149] When it is determined that the user gives priority to
economics, or when the user chooses to give priority to economics
(YES in step S13), the control determination unit 11 reduces the
amount of water to be boiled and computes the reduced amount of
water to be boiled and the electricity rate incurred to boil the
reduced amount of water to be boiled, so that the total time frame
falls within the lowest electricity rate power time slot (step
S14). In other words, the control determination unit 11 computes
the amount of water that can be boiled within a remaining time
frame that is obtained by subtracting the charging time frame of
the on-board battery 23 from the lowest electricity rate power time
slot.
[0150] Subsequently, the control determination unit 11 displays, on
the display input unit 15, the reduced amount of water to be boiled
and the electricity rate incurred to boil the reduced amount of
water to be boiled, and asks the user to accept these displayed
inputs (step S15). However, because the user is not necessarily
present in the vicinity of the electric water heater 1 in this case
as well, the user can accept these inputs in advance. In such a
case, no operation is performed to prompt the user to display or
input using the display input unit 15, and therefore step S15 is
skipped. At this moment, when the reduced amount of water to be
boiled and the electricity rate incurred to boil the reduced amount
of water to be boiled are computed, the control determination unit
11 causes the user to use the display input unit 15 to previously
choose whether or not to accept the reduced amount of water to be
boiled and the electricity rate incurred to boil the reduced amount
of water to be boiled, and then stores information indicating the
resultant acceptance or rejection.
[0151] The control determination unit 11 then determines whether
the current time acquired from the clock 12 reaches the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information (step S17). Here, when
it is determined that the current time has not yet reached the
lowest electricity rate time slot (NO in step S17), the control
determination unit 11 returns to step S2 and carries out the steps
subsequent to step S2.
[0152] When, on the other hand, it is determined that the current
time reaches the lowest electricity rate time slot (YES in step
S17), the control determination unit 11 instructs the boiling unit
10 to start boiling the reduced amount of water to be boiled (step
S18). The control determination unit 11 then determines whether the
boiling is ended or not (step S19). When it is determined that the
boiling is not yet ended (NO in step S19), the boiling is continued
until the end thereof.
[0153] When it is determined that the boiling is ended (YES in step
S19), the control determination unit 11 instructs the feeder 13 to
start charging the on-board battery 23 (step S20). Subsequently,
the control determination unit 11 determines whether the charging
of the on-board battery 23 is ended or not (step S21). When it is
determined that the charging of the on-board battery 23 is not yet
ended (NO in step S21), the feeder 13 continues to charge the
on-board battery 23 until the end thereof. When it is determined
that the charging of the on-board battery 23 is ended (YES in step
S21), the control determination unit 11 ends the series of boiling
and battery charging processes.
[0154] FIG. 5 is a diagram showing the relationship among the
time-slot differentiated electricity rate information, the boiling
time period, and the charging time period for charging the on-board
battery 23, the relationship being obtained when economics are
given priority. In this case, because the reduced amount of water
is boiled, both the boiling time period and the charging time
period fall within the lowest electricity rate time slot described
in the time-slot differentiated electricity rate information.
[0155] Next, FIGS. 3 and 6 are used for describing a case in which
the user chooses to prioritize convenience over economics in step
S13.
[0156] When it is determined that the user chooses not to
prioritize economics, or when the user chooses to give priority to
convenience (NO in step S13), the control determination unit 11
computes a boiling start time for boiling the entire amount of
water, instead of keeping the total time frame of the boiling time
frame and the charging time frame within the lowest electricity
rate power time slot (step S22). At this moment, the control
determination unit 11 computes the boiling start time as a time at
which the boiling time frame starts, which is obtained when the end
of the charging time frame in which the charging is performed
subsequent to the boiling, matches an ending time of the lowest
electricity rate power time slot.
[0157] Next, the control determination unit 11 determines whether
the current time acquired from the clock 12 reaches the boiling
start time or not (step S23). When it is determined that the
current time has not yet reached the boiling start time (NO in step
S23), the control determination unit 11 returns to step S2 and
carries out the steps subsequent to step S2. As described above,
repeating the steps subsequent to step S2 of FIG. 2 allows the
control determination unit 11 to constantly deal with the latest
information on the on-board battery 23.
[0158] When it is determined that the current time reaches the
boiling start time (YES in step S23), the control determination
unit 11 instructs the boiling unit 10 to start boiling the entire
amount of water that is not reduced in amount (step S24).
Thereafter, steps S19 to S21 are performed.
[0159] FIG. 6 shows the relationship among the time-slot
differentiated electricity rate information, the boiling time
period, and the charging time period for charging the on-board
battery, the relationship being obtained when convenience is given
priority and the entire amount of water is boiled outside the
lowest electricity rate power time slot. In this case, as shown in
the diagram, the boiling is started before the start of the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information, in order to boil the
entire amount of water without reducing it, and then boiling the
entire amount of water and charging the on-board battery 23 are
ended.
[0160] As described above, because the boiling start time of the
electric water heater 1 is brought forward in accordance with the
remaining level of the on-board battery 23 that is obtained when
the electric car 2 arrives home, it is possible to avoid the
inconvenience in which the water in the electric water heater 1 is
not yet boiled even after the lowest electricity rate time slot. It
is also possible to avoid the inconvenience in which the on-board
battery 23 is not charged enough that the electric car 2 cannot be
moved or reach a destination.
[0161] The remaining level of the on-board battery 23 that is
obtained when the electric car 2 arrives home can be understood
more accurately than when acquiring the remaining level of the
on-board battery 23 in real time. Therefore, more detailed control
can be performed.
[0162] The above has described the control performed so as to
always keep the charging of the on-board battery 23 within the
lowest electricity rate time slot described in the time-slot
differentiated electricity rate information. However, in actuality,
this control might not be enough. For instance, when the electric
car 2 is used before the lowest electricity rate time slot
described in the time-slot differentiated electricity rate
information ends, the on-board battery 23 might not be charged
enough that the electric car 2 cannot be used. In this case, a time
at which the charging should be ended is input through the display
input unit 15, and then the control determination unit 11 performs
the above-described operations using the time at which the charging
should be ended, instead of using the ending time of the lowest
electricity rate time slot described in the time-slot
differentiated electricity rate information. Accordingly, the
control determination unit 11 can be caused to perform the same
operations as those described above, achieving the effects same as
or better than those described above.
[0163] Moreover, the above has described the basic conditions where
the on-board battery 23 is charged fully due to its
characteristics, but this charging method is not necessarily
preferred in terms of energy saving. For example, the user may
predict a distance that the electric car 2 travels the following
day (or a charge amount corresponding to the travel distance),
input the travel distance of the next day (or the charge amount
corresponding to the travel distance) by using the display input
unit 15, and then charge the on-board battery 23 to a required
level without charging it fully every time. This can reduce the
amount of time required for the charging, and both the boiling and
the charging can be ended within the lowest electricity rate time
slot described in the time-slot differentiated electricity rate
information
[0164] For example, the on-board navigation device 25 accepts input
of a following day's total travel plan from the user and computes
the distance that the electric car 2 travels the following day (or
the charge amount corresponding to the travel distance). The charge
information detector 22 acquires, from the on-board navigation
device 25, the following day's travel distance (or the charge
amount corresponding to the travel distance), the information
pertaining the current remaining level of the on-board battery 23,
and the information pertaining to the distance between the current
position and the house. The first communication unit 21 transmits
the charge information that includes the remaining level of the
on-board battery 23 that is obtained at the time of arrival at the
house, and the following day's travel distance (or the charge
amount corresponding to the travel distance), the charge
information being detected by the charge information detector 22.
On the basis of the following day's travel distance (or the charge
amount corresponding to the travel distance) and the remaining
level of the on-board battery 23 that is obtained at the time of
arrival at the house, the control determination unit 11 determines
the charge amount of the on-board battery 23 and adjusts the
charging time frame for charging the on-board battery 23 and the
boiling time frame of the electric water heater 1.
[0165] At the time of departure on a certain day, the user may
previously store, in the on-board navigation device 25, routing
information indicating a route from the house to a destination and
routing information indicating a route from the destination to the
house. Then, based on the outward routing information and the
homeward routing information, the control determination unit 11 may
estimate the amount of power that is scheduled to be consumed by
the on-board battery 23 that day, and adjust the charging time
frame for charging the on-board battery 23 and the boiling time
frame of the electric water heater 1.
[0166] The above has described the competition between the electric
water heater 1 and the on-board battery 23 over the power. However,
the same control operations as those described above can be
performed to achieve the same effects, not only in this competition
but also in a competition between the on-board battery 23 and the
electric device (e.g., a washer/dryer, a dish washer, etc.) that
can be operated during the lowest electricity rate time slot
described in the time-slot differentiated electricity rate
information.
[0167] Moreover, in the present embodiment, it is most preferred
that the first communication unit 21 communicate, at all times or
on a regular basis, the information pertaining to the remaining
level of the on-board battery 23 that changes every minute while
the electric car 2 travels. The electric car 2 does not have to be
in a travelling state to perform communication and no problem
arises to communicate the information while the electric car 2 is
parked. The first communication unit 21 may also communicate the
information when the electric car 2 is started up (when getting on
the car) or when the electric car 2 is stopped (when getting off
the car).
[0168] The above has also described the example in which the
electric water heater 1 is used as the electric device, but the
electric device may be an electric boiler that boils water by using
electric heat only.
Embodiment 3
[0169] The electric car 2 according to Embodiment 2 computes the
remaining level of the on-board battery 23 that is obtained at the
time of arrival of the electric car 2 at the installation location
where the power control device 16 (the electric water heater 1) is
installed. In Embodiment 3, on the other hand, a server device
computes the remaining level of the on-board battery 23 that is
obtained at the time of arrival of the electric car 2 at the
installation location where the power control device 16 (the
electric water heater 1) is installed.
[0170] FIG. 8 is a diagram showing an example of a configuration of
a power control system according to Embodiment 3 of the present
invention. Embodiment 3 is described with reference to FIG. 8.
[0171] The power control system shown in FIG. 8 has the electric
water heater 1, the electric car 2, and a server device 3. The
descriptions of the configurations according to Embodiment 3 that
are the same as those of Embodiment 2 are omitted. The server
device 3 mediates the communication between the electric car 2 and
the power control device 16 (the electric water heater 1).
[0172] The on-board navigation device 25 acquires information on a
current position of the electric car 2 and provides information
pertaining to a distance between the current position and the
house.
[0173] The charge information detector 22 acquires information
pertaining to a current remaining level of the on-board battery 23
and the information pertaining to a distance between the current
position of the electric car 2 and an installation location where
the electric water heater 1 (the power control device 16) is
installed (e.g., the house) from the on-board navigation device
25.
[0174] The first communication unit 21 transmits, to the server
device 3, the charge information that includes the information
pertaining to the current remaining level of the on-board battery
23, which is acquired by the charge information detector 22, and
the information pertaining to the distance between the current
position of the electric car 2 and the installation location where
the electric water heater 1 (the power control device 16) is
installed (e.g., the house).
[0175] FIG. 9 is a diagram showing a configuration of the server
device 3 of FIG. 8. The server device 3 has a distance information
receiver 31, a remaining level computing unit 32, and a remaining
level transmitter 33.
[0176] The distance information receiver 31 receives, from the
electric car 2, the charge information that includes the
information pertaining to the current remaining level of the
on-board battery 23 and the information pertaining to the distance
between the current position of the electric car 2 and the
installation location where the electric water heater 1 (the power
control device 16) is installed (e.g., the house).
[0177] The remaining level computing unit 32 computes the remaining
level of the on-board battery 23 obtained at the time of arrival at
the house, on the basis of the received information pertaining to
the current remaining level of the on-board battery 23 and the
received information pertaining to the distance between the current
position and the house. More specifically, the remaining level
computing unit 32 computes the amount of power consumed by the
on-board battery 23 prior to the arrival of the electric car 2 at
the house, on the basis of the received information pertaining to
the distance between the current position and the house. The
remaining level computing unit 32 computes the remaining level of
the on-board battery 23 obtained at the time of arrival at the
house, by subtracting the computed amount of power consumed by the
on-board battery 23 prior to the arrival of the electric car 2 at
the house, from the received current remaining level of the
on-board battery 23.
[0178] The remaining level transmitter 33 transmits, to the power
control device 16, the charge information that includes the
information pertaining to the remaining level of the on-board
battery 23 obtained at the time of arrival at the house, the
remaining level being computed by the remaining level computing
unit 32.
[0179] Prior to the arrival of the electric car 2 at the location
where power is supplied to the electric car 2, the second
communication unit 14 of the power control device 16 receives the
charge information transmitted by the remaining level transmitter
33.
[0180] Note that the processes performed by the control
determination unit 11 are same as those described in Embodiment 2,
thus the description thereof is omitted.
[0181] According to Embodiment 3, the remaining level of the
on-board battery 23 obtained at the time of arrival of the electric
car 2 at the installation location does not have to be computed in
the electric car 2 or the power control device 16. Thus, the number
of processes performed in the electric car 2 and the power control
device 16 can be reduced.
Embodiment 4
[0182] A power control system according to Embodiment 4 of the
present invention is described next. A configuration of the power
control system according to Embodiment 4 is substantially the same
as that of the power control system of Embodiment 2 shown in FIG.
7. Configurations different than those described Embodiment 2 are
described hereinafter.
[0183] The on-board navigation device 25 acquires the information
on the current position of the electric car 2, and provides the
information pertaining to the distance between the current position
and the house, and information pertaining to an estimated arrival
time to the house. Note that the house is an example of the
installation location where the electric water heater 1 (the power
control device 16) is installed.
[0184] The charge information detector 22 acquires, from the
on-board navigation device 25, the information pertaining to the
current remaining level of the on-board battery 23, the information
pertaining to the distance between the current position of the
electric car 2 and the house, and the information pertaining to the
estimated arrival time to the house.
[0185] The charge information detector 22 computes the remaining
level of the on-board battery 23 obtained at the time of arrival of
the electric car 2 at the house, on the basis of the acquired
information pertaining to the current remaining level of the
on-board battery 23 and the acquired information pertaining to the
distance between the current position and the house.
[0186] The first communication unit 21 transmits charge information
that includes the remaining level of the on-board battery 23
obtained at the time of arrival of the electric car 2 at the house,
and the estimated arrival time to the house, the remaining level
and the estimated arrival time being acquired by the charge
information detector 22.
[0187] In response to the remaining level of the on-board battery
23 obtained at the time of arrival of the electric car 2 at the
house, the control determination unit 11 computes a time frame
(charging time frame) required to charge the on-board battery 23,
and a time frame (boiling time frame) required to boil water in the
electric water heater 1. The control determination unit 11
determines the power supply start time of supplying power to the
electric water heater 1 and the charging start time of charging the
on-board battery 23, on the basis of the computed charging time
frame, the computed boiling time frame, and the estimated arrival
time at which the electric car 2 is expected to arrive at the
house.
[0188] FIGS. 10 and 11 are flowcharts, each showing processes
performed by the control determination unit 11 according to
Embodiment 4 of the present invention.
[0189] First, the control determination unit 11 acquires the
boiling start time of the electric water heater 1 that is set in
advance (step S31). The display input unit 15 accepts a setting of
the boiling start time of the electric water heater 1 done by the
user, and the control determination unit 11 stores the boiling
start time set by the display input unit 15.
[0190] Next, the control determination unit 11 computes a time
frame required for the electric water heater 1 to boil water
(boiling time frame Tx) (step S32). The control determination unit
11 then acquires information pertaining to charging of the on-board
battery 23 (charge information), via the second communication unit
14 (step S33). The control determination unit 11 then acquires or
computes a time frame required to charge the on-board battery 23
(charging time frame Ty), on the basis of the acquired charge
information (step S34). In Embodiment 4, the control determination
unit 11 computes the charging time frame Ty based on the remaining
level of the on-board battery 23 obtained at the time of arrival of
the electric car 2 at the house.
[0191] Subsequently, the control determination unit 11 creates a
control plan that includes the previously set boiling start time, a
boiling ending time computed by adding up the boiling start time
and the boiling time frame Tx, a charging start time that indicates
the estimated arrival time of the electric car 2 included in the
acquired charge information, and a charging ending time computed by
adding up the charging start time and the charging time frame Ty
(step S35).
[0192] The control determination unit 11 then refers to the created
control plan to determine whether boiling is scheduled to be
performed within the charging time frame Ty (step S36).
[0193] FIG. 12 is a diagram showing an example of the boiling time
frame and the charging time frame according to Embodiment 4 of the
present invention. As shown in FIG. 12, charging is started at the
estimated arrival time to the house, and the boiling time frame Tx
and the charging time frame Ty overlap with each other. The boiling
time frame Tx and the charging time frame Ty fall within a lowest
electricity rate power time slot Tz. The boiling start time is
later than a start time to of the lowest electricity rate power
time slot Tz, and the charging start time is when the charging is
started as soon as the electric car 2 arrives at the house, and is
same as the estimated arrival time. For example, the control
determination unit 11 determines whether the boiling is scheduled
to be performed within the charging time frame Ty, by determining
whether or not the boiling ending time is later than the estimated
arrival time.
[0194] Here, when it is determined that the boiling is not
scheduled to be performed within the charging time frame Ty (NO in
step S36), no changes need to be made to the created control plan.
Thus, the control determination unit 11 moves to step S48.
[0195] When, on the other hand, it is determined that the boiling
is scheduled to be performed within the charging time frame Ty (YES
in step S36), the control determination unit 11 computes a total
power usage, which is a total of the amount of power used in the
boiling and the amount of power used in the charging of the
on-board battery 23 (step S37).
[0196] Next, the control determination unit 11 determines whether
the total power usage is greater than an allowable power or not
(step S38). When it is determined that the total power usage is
equal to or lower than the allowable power (NO in step S38), no
changes need to be made to the created control plan. Thus, the
control determination unit 11 moves to step S48.
[0197] When it is determined that the total power usage is greater
than the allowable power (YES in step S37), the control
determination unit 11 computes a total time frame by adding up the
boiling time frame Tx and the charging time frame Ty (step S39).
The control determination unit 11 then compares the computed total
time frame with the time-slot differentiated electricity rate
information (step S40).
[0198] Subsequently, the control determination unit 11 determines
whether the total time frame falls within the lowest electricity
rate power time slot Tz (step S41). When it is determined that the
total time frame falls within the lowest electricity rate power
time slot (YES in step S41), the control determination unit 11
changes the control plan in a manner as to bring the boiling time
frame forward (step S44). In other words, the control determination
unit 11 changes the control plan by inversely computing the
charging time frame Ty and the boiling time frame Tx from an ending
time tb of the lowest electricity rate power time slot to determine
the boiling start time.
[0199] FIG. 13 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is brought forward. As shown in FIG. 13, the charging is
started after the end of the boiling, and the boiling time frame Tx
and the charging time frame Ty do not overlap with each other. The
boiling time frame Tx and the charging time frame Ty fall within
the lowest electricity rate power time slot Tz. The boiling start
time is later than the start time ta of the lowest electricity rate
power time slot Tz, and the charging ending time is same as the
ending time tb of the lowest electricity rate power time slot
Tz.
[0200] Note in FIG. 13 that the charging ending time is same as the
ending time tb of the lowest electricity rate time slot Tz, but the
charging ending time may be brought forward such that the start
time of the boiling time frame Tx becomes the same as the start
time ta of the lowest electricity rate time slot Tz.
[0201] The control determination unit 11 determines the charging
ending time in a manner as to match the charging ending time and
the ending time tb of the lowest electricity rate power time slot,
and determines the charging start time in accordance with the
determined charging ending time. The control determination unit 11
also determines the boiling ending time such that the boiling is
ended immediately prior to the determined charging start time, and
determines the boiling start time in accordance with the determined
boiling ending time.
[0202] However, when it is determined that the total time frame
does not fall within the lowest electricity rate power time slot
(NO in step S41), the control determination unit 11 determines
whether or not the boiling time frame Tx is longer than a time
frame T1 between a current time and the estimated arrival time
(step S42). When it is determined that the boiling time frame Tx is
longer than the time frame T1 between the current time and the
estimated arrival time (YES in step S42), the control determination
unit 11 determines whether or not the boiling can be performed
outside the lowest electricity rate time slot (step S43). Note that
the control determination unit 11 causes the user to previously use
the display input unit 15 to select whether the boiling is possible
outside the lowest electricity rate time slot, and then stores
information indicating the results of the user's selection.
[0203] In addition, the control determination unit 11 may inquire
the user whether the boiling is performed outside the lowest
electricity rate time slot or not. In this case, the control
determination unit 11 transmits, via the second communication unit
14 to the electric car 2, information for inquiring the user
whether the boiling is performed outside the lowest electricity
rate time slot. The on-board navigation device 25 then accepts a
selection made by the user as to whether the boiling is performed
outside the lowest electricity rate time slot or not, and transmits
the accepted information via the first communication unit 21 to the
power control device 16. Then, based on the information transmitted
by the electric car 2, the control determination unit 11 then
determines whether the boiling can be performed outside the lowest
electricity rate time slot.
[0204] When it is determined that the boiling can be performed
outside the lowest electricity rate time slot (YES in step S43),
the control determination unit 11 changes the control plan in a
manner as to bring the boiling time frame forward (step S44). In
other words, the control determination unit 11 changes the control
plan by inversely computing the charging time frame Ty and the
boiling time frame Tx from the ending time tb of the lowest
electricity rate power time slot to determine the boiling start
time.
[0205] FIG. 14 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is brought forward and when the boiling is performed outside
the lowest electricity rate time slot. As shown in FIG. 14, the
charging is started after the end of the boiling, and the boiling
time frame Tx and the charging time frame Ty do not overlap with
each other. The charging time frame Ty falls within the lowest
electricity rate power time slot Tz, but the boiling time frame Tx
exceeds the lowest electricity rate power time slot Tz. The boiling
start time is sooner than the start time to of the lowest
electricity rate power time slot Tz, and the charging ending time
is same as the ending time tb of the lowest electricity rate power
time slot Tz.
[0206] The control determination unit 11 determines the charging
ending time in a manner as to match the charging ending time and
the ending time tb of the lowest electricity rate power time slot,
and determines the charging start time in accordance with the
determined charging ending time. The control determination unit 11
also determines the boiling ending time such that the boiling is
ended immediately prior to the determined charging start time, and
determines the boiling start time in accordance with the determined
boiling ending time.
[0207] When it is determined that the boiling time frame Tx is
equal to or shorter than the time frame T1 between the current time
and the estimated arrival time (NO in step S42), or when it is
determined that the boiling cannot be performed outside the lowest
electricity rate time slot (NO in step S43), the control
determination unit 11 determines whether or not the boiling time
frame Tx can be segmented (step S45). Note that the electric device
include an electric device in which an operating time frame thereof
can be segmented, and an electric device in which an operating time
frame cannot be segmented. The control determination unit 11
determines whether the boiling time frame Tx can be segmented or
not, by storing information pertaining to the possibility of
segmentation of an operating time frame, with respect to each
electric device.
[0208] When it is determined that the boiling time frame Tx can be
segmented (YES in step S45), the control determination unit 11
changes the control plan in a manner as to segment the boiling time
frame Tx (step S46). The control determination unit 11 segments the
boiling time frame Tx into a first boiling time frame Tx1, which is
prior to the charging start time and falls within the lowest
electricity rate time slot Tz, and a second boiling time frame Tx2,
which is after the charging ending time.
[0209] FIG. 15 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling time
frame is segmented. As shown in FIG. 15, the charging is started
after the end of the boiling, and the boiling is started again
after the end of the charging. The boiling time frame Tx and the
charging time frame Ty do not overlap with each other. The boiling
time frame Tx is segmented into the first boiling time frame Tx1
and the second boiling time frame Tx2. The first boiling time frame
Tx1 is prior to the charging start time and falls within the lowest
electricity rate time slot Tz. The second boiling time frame Tx2
follows the charging ending time and exceeds the lowest electricity
rate time slot Tz. The boiling start time of the first boiling time
frame Tx1 is same as the start time to of the lowest electricity
rate power time slot Tz, and the charging ending time of the first
boiling time frame Tx1 is same as the ending time tb of the lowest
electricity rate power time slot Tz. The boiling start time of the
second boiling time frame Tx2 follows immediately after the ending
time tb of the lowest electricity rate power time slot Tz.
[0210] The control determination unit 11 segments the boiling time
frame Tx into the first boiling time frame Tx1 and the second
boiling time frame Tx2 such that a total time frame obtained by
adding up the first boiling time frame Tx1 and the charging time
frame Ty falls within the lowest electricity rate power time slot
Tz.
[0211] The control determination unit 11 determines the charging
ending time in a manner as to match the charging ending time and
the ending time tb of the lowest electricity rate power time slot,
and determines the charging start time in accordance with the
determined charging ending time. The control determination unit 11
also determines the boiling ending time of the first boiling time
frame Tx1 such that the boiling is ended immediately prior to the
determined charging start time, and determines the boiling start
time of the first boiling time frame Tx1 in a manner as to match
the boiling start time and the start time ta of the lowest
electricity rate power time slot. The control determination unit 11
further determines the boiling start time of the second boiling
time frame Tx2 such that the boiling starts again immediately after
the charging ending time, and determines the boiling ending time of
the second boiling time frame Tx2 in accordance with the determined
boiling start time of the second boiling time frame Tx2.
[0212] When it is determined that the boiling time frame Tx cannot
be segmented (NO in step S45), the control determination unit 11
changes the control plan such that the boiling is performed after
the charging is performed (step S47).
[0213] FIG. 16 is a diagram showing an example of the boiling time
frame and the charging time frame obtained when the boiling is
performed after the charging is performed. As shown in FIG. 16, the
boiling is started after the end of the charging, and the boiling
time frame Tx and the charging time frame Ty do not overlap with
each other. Although the charging time frame Ty falls within the
lowest electricity rate power time slot Tz, the boiling time frame
Tx exceeds the lowest electricity rate power time slot Tz. The
charging ending time is same as the ending time tb of the lowest
electricity rate power time slot Tz, and the boiling start time
follows immediately after the charging ending time.
[0214] Note in FIG. 16 that the charging ending time is same as the
ending time tb of the lowest electricity rate time slot Tz, but the
charging ending time may be brought forward such that the start
time of the boiling time frame Tx becomes the same as the start
time ta of the lowest electricity rate time slot Tz.
[0215] The control determination unit 11 determines the charging
ending time in a manner as to match the charging ending time and
the ending time tb of the lowest electricity rate power time slot,
and determines the charging start time in accordance with the
determined charging ending time. The control determination unit 11
also determines the boiling start time such that the boiling is
started immediately after the determined charging ending time, and
determines the boiling ending time in accordance with the
determined boiling start time.
[0216] Next, the control determination unit 11 controls the boiling
of the electric water heater 1 and the charging of the on-board
battery 23 in accordance with the control plan (step S48).
[0217] Note that, in the present embodiment, when the charging is
not ended by the ending time of the lowest electricity rate time
slot, the control determination unit 11 may display a charged
amount or a remaining charging time frame on the display input unit
15 and causes the user to select whether or not to continue to
charge the battery.
[0218] In FIGS. 4 to 6 and 12 to 16, the power consumed in the
boiling and the power consumed in the charging are shown in
rectangular shapes. In actuality, however, because these consumed
powers change with time, they do not necessarily form rectangular
shapes. When the power consumed by the electric water heater 1
(electric device) lowers and does not exceed the allowable power
even when the boiling and the charging are performed
simultaneously, the charging may be started prior to the end of the
boiling.
[0219] Moreover, the lowest electricity rate time slot may be not
only a predetermined time slot (e.g., 11 p.m. to 7 a.m.), but also
a lowest electricity time slot of a certain day that is acquired
from a server and provided by a power company.
[0220] When the power control system has a solar power generation
system or a fuel cell, the lowest electricity rate time slot may be
a time slot producing a surplus amount of generated power, which
is, for example, between 9 a.m. and 4 p.m. on a sunny day.
[0221] As in the power control system of Embodiment 3 shown in FIG.
8, the flowcharts of FIGS. 10 and 11 may be shared by the server
device and the power control device by using the server device in
the power control system of Embodiment 4 of the present invention.
For instance, allowing the server device to carry out the processes
of steps S33 and S34 of FIG. 10 can eliminate the process of
computing the arrival time to the installation location or the
remaining level of the on-board battery 23 obtained at the time of
arrival in the electric car 2 and the power control device 16. This
reduces the number of processes performed in the electric car 2 and
the power control device 16.
[0222] In addition, when the server device computes the arrival
time of the electric car 2 and the remaining level of the on-board
battery 23, traffic information on a road used by the electric car
2 and weather information can be acquired from another server
device and referred to, so that the arrival time can be computed
with a high degree of accuracy in the light of a delay in the
arrival time caused due to a traffic jam, and so that the remaining
level of the on-board battery 23 can be computed with a high degree
of accuracy in the light of the amount of electricity consumed by
the on-board battery as a result of using a windshield wiper in the
rain or as a result of using air-conditioning equipment.
[0223] Moreover, in the power control system equipped with the
server device, not only is it possible to cause the server device
to compute the arrival time to the installation location and the
remaining level of the on-board battery obtained at the time of
arrival, but also the server device can be caused to perform a part
or all of the processes described in the flowcharts of FIGS. 10 and
11.
Embodiment 5
[0224] FIG. 17 is an overview showing an example of a configuration
of a power control system according to Embodiment 5 of the present
invention. The power control system has an electric device 101 and
an electric car 201. The electric device 101 is disposed in an
average residential house 100. The electric device 101 has a
charger.
[0225] The charger may be a single device. In Embodiment 5,
however, the charger (charging unit) is integrated with the
electric device, and the electric device equipped with the charger
has, outside the house, a connecting unit for charging the electric
car 201.
[0226] Note that the present embodiment describes a case in which
the charger is installed in the house to perform charging, but the
charger may be installed in a bicycle parking lot or a car parking
lot of a store, an office, a factory and other facilities to charge
the electric car. In a commercial facility or a public facility,
the electric device with the charger may be not only a household
electric device but also an electric device installed outside, such
as a user recognition device, an automatic fare-adjustment machine,
and an automatic vending machine.
[0227] The electric car 201 is mounted with a rechargeable battery
211, and an on-board charging circuit 212 for charging the
rechargeable battery 211. A user inserts a charge plug 213 of the
electric car 201 into a connecting unit (outlet) 111, and controls
current/voltage of thus obtained household AC power by means of the
charging circuit 212, to charge the rechargeable battery 211.
[0228] In the present embodiment, an electric device that is
partially installed in a yard of the residential house 100 or
outside a garage is supposedly used as the electric device that is
equipped with the charger for performing charging through the
charge plug 213. The part of the electric device that is installed
outside is, for example, an outdoor unit 102 or a storage tank 103
of an electric water heater, a compressor unit of an air
conditioner, or lighting equipment installed in the garage or the
like. Each of these devices is equipped with the charge connecting
unit (outlet) 111. The electric car 201 can be charged easily by
inserting the charge plug 213 into this connecting unit 111. Note
that a part of the on-board charging circuit 212 may be provided in
the electric device 101.
[0229] An advantage of providing the charger in the electric device
101 installed outside the house is that, by previously installing
the electric device 101 having this charger, a newly purchased
electric car or electric bicycle can be connected to the charger of
the electric device 101 and charged in a car parking lot or a
bicycle parking lot without any major electric construction (a
construction for adding more distribution boards, a wiring
construction between a distribution board and the outside the
house, an installation construction for installing a charge outlet
outside, etc.).
[0230] Note that the electric device 101 with the charger may be
not only lighting equipment, air-conditioning equipment, an
electric water heater or hot water storage equipment, but also
other electric device having at least a part of an electric device
main body function installed outside.
[0231] The electric car 201 has a navigation unit 214 (not shown)
and a communication unit 215. The navigation unit 214 acquires
positional information pertaining to a current position of the
electric car 201 away from the house and a position of a
destination, distance information pertaining to the distance
between the current position and the destination, and time frame
information pertaining to a drive time frame taken between the
current position and the destination and an estimated arrival time
to the destination. The navigation unit 214 acquires charge
information pertaining to charging of the rechargeable battery
211.
[0232] When the destination is taken as the house where the charger
is present, the navigation unit 214 measures the current position
of the electric car 201, and computes the information pertaining to
the estimated arrival time (an estimated return time), based on the
distance between the current position and the house where the
charger is present, and based on a moving speed and a current
time.
[0233] Furthermore, the navigation unit 214 measures the current
position of the electric car 201, and computes information
pertaining to a necessary charge amount of the rechargeable battery
that needs to be charged when the electric car 201 returns to the
house, on the basis of the distance between the current position
and the house where the charger is present, an electricity energy
amount per travel distance, and a current charge amount of the
rechargeable battery 211.
[0234] The communication unit 215 transmits, to a communication
unit 112 equipped in the electric device 101, the information
acquired by the navigation unit 214 (the positional information on
the current position and the destination, the distance information
on the distance between the current position and the destination
(the point where the charger is present), the time frame
information pertaining to a drive time frame taken between the
current position and the destination (the point where the charger
is present) and an estimated arrival time to the destination, and
the information pertaining to the necessary charge amount of the
rechargeable battery). In other words, the communication unit 215
transmits the charge information acquired by the navigation unit
214, prior to the arrival of the electric car 201 at a location
where power is supplied to the electric car 201. As a result, the
electric device 101 can understand the statuses of the electric car
201 and the rechargeable battery 211 away from the house. A
cell-phone communication network or a data communication network is
used in the communication.
[0235] In the present embodiment, calculation of the estimated
arrival time and calculation of the necessary charge amount of the
rechargeable battery 211 are performed by the electric vehicle (the
electric car 201), and the results of the calculations are
transmitted to the charger (the electric device 101). However,
necessary information on the current position and the like may be
transmitted from the electric vehicle to the charger, and then the
charger may perform the calculations.
[0236] The power control system further has a server device for
mediating the communication of the information between the charger
and the electric vehicle. The information on the current position
and the like may be transmitted from the electric vehicle to the
server device, to allow the server device to perform the
calculations. The results of the calculations may be transmitted to
the charger.
[0237] The first communication unit 21 of the electric car 2
transmits current positional information on the electric car 2 and
the positional information of the destination (the house) to the
server device. The server device computes, on behalf of the
on-board navigation device 25, the distance information pertaining
to the distance between the current position and the destination
(the point where the charger is present), and the time frame
information pertaining to a drive time taken between the current
position and the destination (the point where the charger is
present) and the estimated arrival time to the destination. The
computed information is transmitted to the communication unit 112
of the electric device 101.
[0238] Furthermore, the first communication unit 21 of the electric
car 2 transmits the information on the current remaining level of
the on-board battery 23 to the server device, and the server
device, on behalf of the charge information detector 22, computes
the remaining level of the on-board battery 23 obtained at the time
of arrival of the electric car at the destination. The computed
remaining level is transmitted to the communication unit 112 of the
electric device 101.
[0239] Accordingly, the arrival time to the installation location
and the remaining level of the on-board battery 23 obtained at the
time of arrival, do not have to be computed in the electric car 2
or the power control device 16, reducing the number of processes
performed in the electric car 2 and the power control device
16.
[0240] In addition, when the server device computes the arrival
time of the electric car 2 and the remaining level of the on-board
battery 23, traffic information on a road used by the electric car
2 and weather information can be acquired from another server
device and referred to, so that the arrival time can be computed
with a high degree of accuracy in the light of a delay in the
arrival time caused due to a traffic jam, and so that the remaining
level of the on-board battery 23 can be computed with a high degree
of accuracy in the light of the amount of electricity consumed by
the on-board battery as a result of using a windshield wiper in the
rain or as a result of using air-conditioning equipment.
[0241] With regard to the estimated arrival time, a passenger may
calculate the estimated arrival time and input the calculated
estimated arrival time into the navigation unit 214.
[0242] Note that the point where the charger is present may not
only be the house. The navigation unit 214 may search for the
charger present in the vicinity of the current position of the
electric car 201. Moreover, friends' houses or facilities where the
battery can be charged may be previously registered in the
navigation unit 214. In the present embodiment, the point where the
charger is present is described as the house. The estimated arrival
time is described as the estimated return time.
[0243] Next, the electric device of Embodiment 5 of the present
invention and peripheral equipment thereof are described. FIG. 18
is a block diagram showing an example of the configuration of the
power control system according to Embodiment 5 of the present
invention. The same functions as those shown in FIG. 17 are denoted
with the same reference numerals to describe FIG. 18.
[0244] The power control system shown in FIG. 18 has electric
devices 101, 107, an ampere breaker 105, branch breakers 106, 108,
and the electric car 201.
[0245] The ampere breaker 105 is disposed on the upstream side of
an AC power supply 104 (100 V or 200 V in a household AC power
supply), and, as in Patent Literature 2 described in Background
Art, blocks supply of power when the amount of power used in the
entire household exceeds a contract power capacity.
[0246] When supplying power from the AC power supply 104 to the
electric device 101, the branch breaker 106 (supplying, for
example, 20-A allowable current) is installed between the AC power
supply 104 and the ampere breaker 105 in order not to supply
overcurrent when the electric device 101 shorts out or operates
abnormally. The electric device 107 and the branch breaker 108 are
same as the electric device 101 and the branch breaker 106.
[0247] The electric device 101 has the connecting unit 111, the
communication unit 112, a charging unit 113, a total power usage
detector 114, a functional block 115 for the electric device, an
electric device control unit 116, a first power usage detector 117,
a charge control unit 118, a second power usage detector 119, a
time frame adjusting unit 120, and a user instructing unit 124.
[0248] The electric device 101 of Embodiment 5 has the charging
unit 113 outside the house, and uses the charging unit 113 to
charge, outside the house, an electric vehicle mounted with the
rechargeable battery 211, such as the electric car 201 and an
electric bicycle.
[0249] The connecting unit 111 is, for example, a plug, and may be
connected to a rechargeable battery of a device other than the
electric vehicle, to charge the device. Note that the connecting
unit 111 does not have to be a plug.
[0250] A configuration of the electric device 101 is described
hereinafter in detail.
[0251] The total power usage detector 114 is, for example, a power
meter for detecting a total power usage in the entire electric
device 101, including the power supplied to the charging unit 113.
Note that the total power usage detector 114 may be provided as a
casing independent from the electric device 101, and configured as
a plug-shaped adapter for communicating information on the detected
total power usage to the electric device 101.
[0252] The original functions specific to the electric device 101
are realized by the functional block 115 of the electric device
101, and the electric device control unit 116 controlling the
functional block 115. For example, the functional block 115 is an
actuator such as a compressor or an inverter circuit, and serves as
a hot-water supply function when the electric device 101 is an
electric water heater, a hot water storage function when the
electric device 101 is hot water storage equipment, an
air-conditioning function when the electric device 101 is an air
conditioner, and a lighting function when the electric device 101
is lighting equipment. The electric device control unit 116 is, for
example, a microcomputer or a peripheral unit thereof, and controls
the functional block 115 of the electric device 101.
[0253] The first power usage detector 117 is inserted into a
power-supply line between the functional block 115 and the electric
device control unit 116, to detect power used by the original
functions of the electric device 101.
[0254] FIG. 19 is a diagram showing an example of power usage of
the electric device 101 according to Embodiment 5 of the present
invention. For example, an electric water heater uses a power of
1160 W to heat water during summer and 2000 W when heating water at
high temperatures in winter. Also, an air conditioner uses, for
example, a power of 85 to 1150 W for cooling, and 80 to 1980 W for
heating. Moreover, for example, a lamp uses a power of 36 W. As
shown in FIG. 19, the electric water heater or the air conditioner
uses a power of 1000 to 2000 W at a maximum.
[0255] The electric device 101 has, as charging functions, the
charging unit 113 for charging the rechargeable battery 211 of the
electric car 201 connected to the connecting unit 111, and the
charge control unit 118 for controlling the charging unit 113. The
charging unit 113 has a voltage/current conversion function for
producing voltage and current suitable for charging the
rechargeable battery 211, depending on the condition of the
rechargeable battery 211, and a charging status detection function
for detecting a charging status of the rechargeable battery
211.
[0256] The second power usage detector 119 is inserted into a
power-supply line between the charging unit 113 and the charge
control unit 118, to detect power used by the charging unit
113.
[0257] For instance, it takes approximately eight hours to charge
the rechargeable battery 211 of the electric car 201 by using a
household 200 V-15 A power supply at 16 kWh. In other words, when
the functional block 115, the electric device control unit 116, the
charging unit 113 and the charge control unit 118 of the electric
device 101 are operated simultaneously, the maximum power of 4000
to 5000 W is used. In this case, the branch breaker 106 blocks
supply of power to the electric device 101.
[0258] The electric device 101 has the time frame adjusting unit
120 for preventing the branch breaker 106 from blocking the power
supply. The time frame adjusting unit 120 understands the power
used by the original functions of the electric device 101 and the
power used by the charging functions, to operate these functions
simultaneously, allocate the power used by these functions, or
operate either the former or latter functions first, in accordance
with an electricity rate computed based on the understood power. In
this manner, the time frame adjusting unit 120 controls the power
to be used and the time frames in which the power is used.
[0259] Specifically, based on the charge information received by
the communication unit 112, the time frame adjusting unit 120
determines the power supply start time of supplying power to the
electric device 101 and the charging start time of charging the
rechargeable battery 211, such that the supply of power to the
electric device 101 and the charging of the rechargeable battery
211 are ended by a predetermined time.
[0260] The charge information includes the estimated arrival time
at which the electric car 201 arrives at an installation location
where the electric device 101 is installed, the estimated arrival
time being obtained based on the distance between the current
position of the electric car 201 and the installation location
where the electric device 101 is installed. The time frame
adjusting unit 120 determines the power supply start time of
supplying power to the electric device 101 and the charging start
time of charging the rechargeable battery 211, such that the
charging start time of charging the rechargeable battery 211
follows the estimated arrival time and that a total of power
required to charge the rechargeable battery 211 and power used for
operating the electric device 101 does not exceed a predetermined
value.
[0261] Note that, in the following description, the operation of
the electric device 101 means the operation of the functional block
115 of the electric device 101. For instance, when the electric
device 101 is an electric water heater that has a boiling function
for boiling water and a charging function for charging the
rechargeable battery 211, the operation of the electric device 101
means that the boiling function, which is one of the original
functions of the electric water heater, is executed.
[0262] Moreover, the charge information further includes
information on the remaining level of the rechargeable battery 211
obtained at the time of arrival of the electric car 201 at the
installation location where the electric device 101 is installed,
the remaining level being obtained based on the distance between
the current position of the electric car 201 and the installation
location. The time frame adjusting unit 120 computes a time frame
required to charge the rechargeable battery 211, in accordance with
the remaining level of the rechargeable battery 211, and then
determines the power supply start time of supplying power to the
electric device 101 and the charging start time of charging the
rechargeable battery 211, on the basis of the computed time frame
required to charge the rechargeable battery 211 and the estimated
arrival time.
[0263] The time frame adjusting unit 120 has a priority order
storage unit 121, an electricity rate information storage unit 122,
and a power usage calculator 123. The priority order storage unit
121 stores a priority order of the functions of the electric device
101 and the charging functions, which are operated preferentially.
The electricity rate information storage unit 122 stores time-slot
differentiated electricity rate information of the AC power supply
104. The power usage calculator 123 controls an operation of the
electric device 101 and power supplied from the charging unit 113
to the rechargeable battery 211, such that a sum of the power used
by the electric device 101 and the power used by the charging unit
113 is kept equal to or lower than a predetermined value (a supply
capacity of the AC power supply 104).
[0264] Although not shown, the time frame adjusting unit 120 has a
clock for adjusting an operating time frame for operating the
electric device 101 and a charging time frame for charging the
charging unit 113.
[0265] The priority order storage unit 121 stores the priority
order according to the power used by the electric device 101, the
charging status of the rechargeable battery 211, and the time-slot
differentiated electricity rate information. The priority order
storage unit 121 also sets a priority order convenient for the
user. The priority order storage unit 121 may learn in accordance
with the use conditions of the electric device 101 and the
rechargeable battery 211.
[0266] The electricity rate information storage unit 122 can
previously store the time-slot differentiated electricity rate
information or download (not shown) through a communication network
the time-slot differentiated electricity rate information that
changes depending on power demands. Another thing considered is
that the electricity rates can be lowered when generating power
from a solar power generation system or a fuel cell.
[0267] Based on the time-slot differentiated electricity rate
information stored in the electricity rate information storage unit
122, the time frame adjusting unit 120 computes an electricity rate
incurred when starting the operation of the electric device 101
prior to the charging start time and an electricity rate incurred
when starting the operation of the electric device 101 after the
charging ending time, and selects the lowest electricity rate out
of the computed electricity rates.
[0268] FIG. 20 is a diagram showing an example of the time-slot
differentiated electricity rate information according to Embodiment
5 of the present invention. FIG. 20 shows the time-slot
differentiated electricity rate information of the time-slot
differentiated electricity rate system used in an all-electric
house that uses a 200-V power supply. The electricity rate here
varies according to time slots. The electricity rate information
storage unit 122 stores an electricity rate per 1 kWh for each time
slot.
[0269] As shown in FIG. 20, the electricity rate is 9 yen/kWh
between 11 p.m. and 7 a.m., and 23 yen/kWh between 7 a.m. and 10
a.m. The electricity rate between 10 a.m. and 5 p.m. is 33 yen/kWh
during summer (from July to September) and 28 yen/kWh in the
seasons other than summer. The electricity rate is 23 yen/kWh
between 5 p.m. and 11 p.m.
[0270] The power usage calculator 123 acquires a power usage value
of the functional block 115 of the electric device 101, which is
detected by the first power usage detector 117, and a power supply
value indicating power supplied from the charging unit 113 to the
rechargeable battery 211, which is detected by the second power
usage detector 119, and then calculates a sum of the power used by
the electric device 101 and the power used by the charging unit
113. Alternatively, the power usage calculator 123 may use a power
value measured by the total power usage detector 114, as the sum of
the power used by the electric device 101 and the power used by the
charging unit 113. Moreover, the power usage calculator 123 may
learn the power usage value of the functional block 115 of the
electric device 101 and the power usage value of the charging unit
113, and store the power used in each operating mode of the
electric device 101 or each charging mode of the charging unit
113.
[0271] In this manner, the power usage calculating unit 123 obtains
the entire power used by the electric device 101, including the
power used in charging, to control the following three power supply
operations such that the power used in the electric device 101
becomes equal to or lower than a predetermined value (allowable
power).
[0272] (1) The power usage calculator 123 acquires the power used
by the functional block 115 of the electric device 101 and the
power used by the charging unit 113. When a margin of the total
power usage is greater than the predetermined value, the power
usage calculator 123 operates the functional block 115 and the
charging unit 113 of the electric device 101 at the same time.
[0273] (2) The power usage calculator 123 acquires the power used
by the functional block 115 of the electric device 101 and the
power used by the charging unit 113. When the margin of the total
power usage is less than the predetermined value, the power usage
calculator 123 allocates the power used in the functional block 115
of the electric device 101 and the power used in the charging unit
113, and operates the functional block 115 and the charging unit
113 of the electric device 101 at the same time.
[0274] For example, when the electric device 101 is an electric
water heater, the power usage of the electric water heater can be
reduced temporarily by switching the operating mode thereof from a
boiling mode to a heating mode. When the electric device 101 is an
air conditioner, the power usage of the air conditioner can be
reduced temporarily by changing the operating mode thereof,
changing a set temperature thereof, or reducing the air volume. In
addition, the charging unit 113 can reduce the amount of power
(current or voltage) supplied to the rechargeable battery 211.
[0275] (3) The power usage calculator 123 acquires the power used
by the functional block 115 of the electric device 101 and the
power used by the charging unit 113. When the margin of the total
power usage is less than the predetermined value, the power usage
calculator 123 operates the functional block 115 and the charging
unit 113 of the electric device 101 at different times, instead of
operating the functional block 115 and the charging unit 113 at the
same time.
[0276] The present embodiment mainly describes (3) mentioned
above.
[0277] Note that a value substantially the same as the allowable
current of the branch breaker 106, a value equal to or lower than
the allowable current of the branch breaker 106, or a value
slightly higher than the allowable current of the branch breaker
106, is initially set as the predetermined value, which is an upper
limit of the total power usage.
[0278] The user instructing unit 124, a remote controller, for
example, remotely displays an operating status of the electric
device 101 and remotely controls the operation of the electric
device 101. The user instructing unit 124 displays the statuses of
the settings or operating statuses of the electric device control
unit 116, the charge control unit 118 and the time frame adjusting
unit 120, and accepts a setting operation and control operation on
the operation of the electric device 101 by the user, and a setting
operation and control operation on charging of the rechargeable
battery 211 by the user. As a result, the user can set and control
the operation of the electric device 101 and charging of the
rechargeable battery 211.
[0279] Infrared communication, wireless communication (radio
waves), wire communication, or electric lamp line communication,
can be used as a communication medium between the electric device
101 and the user instructing unit 124. Furthermore, the user
instructing unit 124 can be fixedly installed on a wall of a
kitchen, as with a remote controller of an electric water heater,
or carried by the user and used in a location selected by the user,
as with a remote controller of an air conditioner.
[0280] The communication unit 112 receives the charge information
pertaining to charging of the rechargeable battery 211 of the
electric car 201 from the communication unit 215 of the electric
car 201, prior to the arrival of the electric car 201 at the
location where power is supplied to the electric car 201. The
communication unit 112 outputs the received charge information to
the user instructing unit 124, the charge control unit 118 and the
time frame adjusting unit 120. The user instructing unit 124
displays the charge information received by the communication unit
112. At least the following three timings can be considered in the
communication of the charge information between the communication
unit 215 and the communication unit 112. Needless to say, the
communication can be performed at all times or on a regular basis
(ever several minutes, for example), as long as the communication
environment allows.
[0281] (1) When the passenger of the electric car 201 manipulates
the navigation unit 214 and sets the destination to the house (the
location where the charger is present), the communication unit 215
transmits the charge information to the communication unit 112.
[0282] (2) When the electric car 201 moves toward the house, which
is the destination, the communication unit 215 transmits the charge
information to the communication unit 112.
[0283] (3) When a time at which the electricity rate changes is
reached, or, in other words, when it is 7 a.m., 10 a.m., 5 p.m., or
11 p.m., the communication unit 215 transmits the charge
information to the communication unit 112.
[0284] As described above, in the communication timings described
in (1) and (2) above, the time frame adjusting unit 120 acquires
the charge information (the positional information pertaining to
the current position of the electric car 201, the distance
information pertaining to the distance between the current position
and the house, and the time frame information pertaining to a drive
time frame taken between the current position and the destination
and the estimated arrival time to the house), and uses the acquired
estimated return time to create a time frame adjusting plan for the
operation of the functional block 115 and the electric device 101
and the charging of the rechargeable battery 211, before the
electric car 201 returns to the house.
[0285] Moreover, in the communication timing described in (3)
above, the time frame adjusting unit 120 reviews a created plan
showing a scheduled operation of the functional block 115 of the
electric device 101 and scheduled charging of the rechargeable
battery 211 when the electricity rate changes, by acquiring the
latest condition (the latest charge information) of the electric
car 201. For example, even when the destination is not set in the
navigation unit 214, in the communication time described in (3) the
time frame adjusting unit 120 can acquire the earliest estimated
return time that is obtained assuming that the electric car 201
returns to the house directly from the current position
thereof.
[0286] The charging status of the rechargeable battery 211 obtained
by the charging unit 113, and control of voltage/current performed
in accordance with the charging status, are now described with
reference to FIG. 21.
[0287] FIG. 21 is a diagram showing a charging sequence obtained
when the rechargeable battery is a lithium battery. In FIG. 21, the
horizontal axis represents the charging time frame, the scales on
the left vertical axis represent voltage, and the scales on the
right vertical axis represent charging current and charging
capacity. A reference numeral "1C" represents a unit of a current
value at which constant current discharge is ended one hour after
the constant current discharge of cells having the capacity
indicated by a nominal capacity value.
[0288] As shown in FIG. 21, when charging is started when the
charging status is close to 0 (the left side of the graph), at
first the charging unit 113 starts charging at a constant current
(1C current) (constant current charging mode). At this moment, the
voltage increases as the charging continues, and the charging
capacity is charged substantially in proportion to the time.
[0289] Then, when the charging capacity becomes equal to or greater
than 75% (0.75 CAh) as shown in FIG. 21, the charging unit 113
performs charging at a constant voltage (1C voltage) of 4.2 V
(constant voltage charging mode). At this moment, the current
decreases as the charging continues, and the charging capacity
gradually becomes fully charged (1.0 CAh).
[0290] In other words, a large amount of power is required in the
constant current charging mode, but the amount of power required in
the constant voltage charging decreases gradually.
[0291] The constant voltage charging mode requires time because the
current is reduced while keeping the voltage constant, as shown in
FIG. 21. Thus, the charging unit 113 may perform charging in a
pulse charging mode in place of the constant voltage charging mode.
In the pulse charging mode, the charging unit 113 increases the
current to above 4.2 V for only a short period of time during the
charging, and then stops the charging when the voltage becomes
equal to or greater than 4.2 V. When the voltage is less than 4.2
V, the charging is performed again with a pulse of 4.2 V.
[0292] As described above, the charging unit 113 detects the
charging status of the rechargeable battery 211 and controls the
voltage and current used in the charging, in accordance with the
charging status.
[0293] The present embodiment has described the example in which
the charging unit 113 controls the voltage and current used in the
charging. However, the on-board charging circuit 212 of the
electric car 201 may control the voltage and current. The on-board
charging circuit 212 is connected to the charging unit 113 and the
charging control unit 118 by the connecting unit 111, and the
functions thereof are shared by the electric device 101 and the
electric car 201. FIG. 18 is now used as an example to describe
this configuration.
[0294] It should be noted in Embodiment 5 that the electric car 201
corresponds to an example of the electric vehicle, the rechargeable
battery 211 to an example of the rechargeable battery, the electric
device 101 to an example of the electric device and the power
control device, the navigation unit 214 to an example of the charge
information acquiring unit, the communication unit 215 to an
example of the transmitter, the communication unit 112 to an
example of the receiver, the time frame adjusting unit 120 to an
example of the power control unit, and the electricity rate
information storage unit 122 to an example of the electricity rate
information storage unit.
[0295] In the configuration described above, the operations of the
electric device 101 according to Embodiment 5 are described using
the flowchart of FIG. 22. FIG. 22 is a flowchart for illustrating
the operations of the electric device according to Embodiment 5 of
the present invention.
[0296] In the first step S51, the time frame adjusting unit 120
acquires, from the electric device control unit 116, a current
operating status of the functional block 115 of the electric device
101 (operating mode and power used) and a programmed status of a
timer operation (scheduled operation start time, scheduled
operation ending time, and power used between the scheduled
operation start time and the scheduled operation ending time). Note
that, if there is a programmed condition of a timer operation, the
time frame adjusting unit 120 acquires it from the electric device
control unit 116. The operating status and the programmed condition
may be acquired from the user instructing unit 124 (remote
controller).
[0297] The value detected by the first power usage detector 117 or
a current value that is previously stored for each operating mode
of the functional block 115 of the electric device 101, may be used
for computing the power used by the functional block 115 of the
electric device 101.
[0298] In the subsequent step S52, the time frame adjusting unit
120 acquires the charge information that includes at least the
charging status of the rechargeable battery 211, the estimated
return time of the electric car 201 and the necessary charge amount
of the rechargeable battery 211. The time frame adjusting unit 120
acquires, from the charge control unit 118, the charging status of
the rechargeable battery 211 that indicates whether the
rechargeable battery 211 is charged in the constant current
charging mode, the constant voltage charging mode, or the pulse
charging mode. The communication unit 112 receives the charge
information transmitted by the communication unit 215 of the
electric car 201 and outputs the received charge information to the
time frame adjusting unit 120.
[0299] Note that, in the present embodiment, although the estimated
return time of the electric car 201 is acquired from the electric
car 201, the present invention is not limited to such a
configuration. The estimated return time (estimated arrival time)
of the electric car 201 may be computed by the charge control unit
118 by acquiring the positional information of the electric car 201
received by the communication unit 112, the distance information on
the distance to the house, and the time frame information on the
time frame required for the electric car 201 to return to the
house.
[0300] In the subsequent step S53, the time frame adjusting unit
120 acquires the time-slot differentiated electricity rate
information from the electricity rate information storage unit 122.
In the next step S54, the time frame adjusting unit 120 acquires a
user instruction content from the user instructing unit 124. Note
that there might be no user instructions.
[0301] In the subsequent step S55, the time frame adjusting unit
120 acquires a priority order for the operation of the functional
block 115 of the electric device 101 and the charging of the
rechargeable battery 211 of the electric car 201, from the priority
order storage unit 121. The time frame adjusting unit 120 then
determines a priority order on the basis of the power used by the
functional block 115 of the electric device 101 that is acquired in
step S51, the charging status of the rechargeable battery 211
acquired in step S52, and the time-slot differentiated electricity
rate information acquired in step S53. In other words, the time
frame adjusting unit 120 determines which operation to prioritize,
the operation of the functional block 115 of the electric device
101 or the charging of the charging unit 113.
[0302] FIG. 23 is a diagram showing an example of the priority
orders according to Embodiment 5 of the present invention. The time
frame adjusting unit 120 determines any one of priority orders (a)
to (d), on the basis of the charging status of the rechargeable
battery 211 and the time-slot differentiated electricity rate
information.
[0303] According to the priority order (a) and the priority order
(b), the charging status is in the constant current charging mode
(in which the charging capacity is equal to or lower than 75% as
shown in FIG. 21), and a large amount of power is used in the
charging.
[0304] Here, when the time frame adjusting unit 120 refers to the
time-slot differentiated electricity rate information and the time
slot is the lowest electricity rate time slot, the time frame
adjusting unit 120 determines the priority order (a) to prioritize
the charging of the rechargeable battery 211. As a result, when the
rechargeable battery 211 can be charged in the lowest electricity
rate time slot, the rechargeable battery 211 is charged, and the
electric device 101 is operated concurrently if possible.
[0305] When the charging status is in the constant current charging
mode and the time slot is outside the lowest electricity rate time
slot, the time frame adjusting unit 120 determines the priority
order (b) to prioritize the operation of the electric device 101.
As a result, the use of the electric device 101 is given priority
during a main living time slot, and the charging capacity is left
unused during the living-hour time slot so that the rechargeable
battery 211 can be charged at night.
[0306] In the priority order (c) and the priority order (d), the
charging status is in the constant voltage charging mode or the
pulse charging mode (in which the charging capacity is equal to or
greater then 75% as shown in FIG. 21), and a small amount of power
is used. When the charging status is in the constant voltage
charging mode or the pulse charging mode and the time slot is the
lowest electricity rate time slot, the time frame adjusting unit
120 determines the priority order (c) to prioritize the operation
of the electric device 101. Furthermore, when the charging status
is in the constant voltage charging mode or the pulse charging mode
and the time slot is outside the lowest electricity rate time slot,
the time frame adjusting unit 120 determines the priority order (d)
to prioritize the operation of the electric device 101.
[0307] When the charging status is in the constant voltage charging
mode or the pulse charging mode, operating the electric device 101
is given priority, regardless of the time-slot differentiated
electricity rate information, and the charging unit 113 performs
charging using a small required amount of power, if possible.
[0308] The control steps shown in FIG. 22 are described hereinafter
on the basis of the priority orders described above.
[0309] In step S56, the time frame adjusting unit 120 estimates an
operating time frame for operating the functional block 115 of the
electric device 101 and power used for operating the functional
block 115. The time frame adjusting unit 120 computes the operating
time for operating the functional block 115 of the electric device
101 and computes the power used for operating the functional block
115, on the basis of the scheduled operation start time and the
scheduled operation ending time acquired from the electric device
control unit 116.
[0310] In the subsequent step S57, the time frame adjusting unit
120 estimates a charging time frame for charging the rechargeable
battery 211 of the electric car 201 and power used for charging the
rechargeable battery 211. The time frame adjusting unit 120
computes the charging time frame for charging the rechargeable
battery 211 of the electric car 201 and the power used for charging
the rechargeable battery 211, on the basis of the estimated return
time of the electric car 201 and the necessary charging amount of
the rechargeable battery 211 obtained when the electric car 201
returns to the house, which are acquired from the electric car 201.
More specifically, the time frame adjusting unit 120 computes the
charging time frame required for charging the necessary charge
amount, based on the charging start time, which is the estimated
return time of the electric car 201 acquired from the electric car
201. The time frame adjusting unit 120 also computes the power
required for charging the necessary charge amount.
[0311] In the subsequent step S58, the time frame adjusting unit
120 estimates a total power usage that is obtained by adding up the
power used for operating the functional block 115 of the electric
device 101 and the power used for charging the rechargeable battery
211.
[0312] In the next step S59, the time frame adjusting unit 120
overlaps the operating time frame for operating the functional
block 115 of the electric device 101 and the charging time frame
for charging the rechargeable battery 211, and estimates an
electricity rate that is incurred when operating the functional
block 115 and charging the rechargeable battery 211.
[0313] In the subsequent step S60, the time frame adjusting unit
120 creates a control plan for the operation of the functional
block 115 of the electric device 101 and the charging performed on
the rechargeable battery 211. The time frame adjusting unit 120
compares the total power usage with the allowable power, which is
the predetermined value. When there exists a time frame in which
the total power usage is greater than the allowable power, the time
frame adjusting unit 120 reviews the control plan. For instance,
the time frame adjusting unit 120 performs adjustment by shifting
the operating time frame and the charging time frame. The time
frame adjusting unit 120 also adjusts the operating time frame and
the charging time frame by shifting, forward and backward, the
operating time frame between the scheduled operation start time of
the functional block 115 of the electric device 101 and the
scheduled operation ending time of the same, and the charging time
frame between the charging start time of the rechargeable battery
211 and the charging ending time of the same, such that the
operating time frame and the charging time frame fall within the
lowest electricity rate time slot as much as possible. This time
frame adjustment is described in detail with reference to the
drawings.
[0314] In the present embodiment, the time frame adjusting unit 120
obtains the estimated return time in step S52. Therefore, the time
frame adjusting unit 120 can stop operations of the other electric
device at the estimated return time to secure available power to
charge the rechargeable battery 211, and start operating the other
electric device once the charging of the rechargeable battery 211
is ended.
[0315] Moreover, the present embodiment can realize the estimated
return time of the electric car 201 alone. However, by accumulating
a current rechargeable amount of the rechargeable battery 211 of
the electric car 201, the time frame adjusting unit 120 can compute
a predicted rechargeable amount or the amount of power required for
charging (necessary charge amount), when the electric car returns
to the house, on the basis of the current rechargeable amount, the
positional information and the distance information.
[0316] The charge control unit 118 can refer to the graph of FIG.
21 shown in the charging capacity and the charging time frame to
acquire the time frame required for charging the rechargeable
battery and to predict the charging ending time when the charging
is started immediately after the electric car returns to the house
at the estimated return time.
[0317] In other words, once the predicted rechargeable amount of
the rechargeable battery 211 is obtained, a rechargeable status of
the time of the return of the electric car can be understood
beforehand. For this reason, the time frame adjusting unit 120 can
use the predicted rechargeable amount to determine which one to
prioritize when the charging of the rechargeable battery 211
overlaps with the operation of the functional block 115 of the
electric device 101.
[0318] For example, when the predicted rechargeable amount is equal
to or lower than the predetermined value (e.g., equal to or lower
than 75% of the fully charged state), the time frame adjusting unit
120 gives priority to the charging of the rechargeable battery 211
over the operation of the functional block 115 of the electric
device 101. When the predicted rechargeable amount is equal to or
greater than the predetermined value, the time frame adjusting unit
120 can give priority to the operation of the functional block 115
of the electric device 101 over the charging of the rechargeable
battery 211.
[0319] In addition, a time at which the charging is ended (the
charging ending time) can be predicted once the time for starting
the charging is determined. Thus, when the charging of the
rechargeable battery 211 is prioritized over the operation of the
functional block 115 of the electric device 101, the time frame
adjusting unit 120 can plan when to start and end operating the
functional block 115 of the electric device 101.
[0320] When the control plan is created in step S60, in step S61
the time frame adjusting unit 120 uses the user instructing unit
(remote controller) 26 or the like to inform the user of the
control plan that includes an operation plan for operating the
functional block 115 of the electric device 101 (the operating
time, the operating content, and the amount of power used), and a
charge plan for charging the rechargeable battery 211 (the charging
start time, the charging ending time, the charge amount, and the
amount of power used). The time frame adjusting unit 120 not only
displays the control plan on the user instructing unit 124 but also
transmits the control plan to the electric car 201 via the
communication unit 112 and causes the navigation unit 214 of the
electric car 201 to display the control plan, thereby informing the
passenger of the control plan.
[0321] Next, in step S62, the time frame adjusting unit 120
determines whether the charging start time gets behind the
estimated return time by a predetermined time frame or more (e.g.,
10 minutes or more) in the created control plan. When it is
determined that the charging start time gets behind the estimated
return time by the predetermined time frame or more (YES in step
S62), in step S63 the time frame adjusting unit 120 transmits the
charging start time to the electric car 201 via the communication
unit 112, and notifies the passenger of the electric car 201 of the
charging start time by displaying the charging start time on the
navigation unit 214 of the electric car 201. As a result, the
passenger can understand that the charging cannot be performed even
after the electric car 201 returns to the house as scheduled, and
can adjust the return time when there is enough time.
[0322] After notifying the passenger of the electric car 201 of the
charging start time, or when it is determined that the charging
start time gets behind the estimated return time by the
predetermined time frame or more (NO in step S62), in step S64 the
electric device control unit 116 and the charge control unit 118
operates the functional block 115 and charges the rechargeable
battery 211 on the basis of the created control plan. Note that,
although not shown, various information may be reacquired on a
regular basis back in step S51, and the control plan may be
reviewed using the latest information, during the execution of the
control plan or while waiting for the control plan to be executed.
Moreover, when the user instructing unit 124 interrupts the
execution of the control plan, the control plan may be changed in
response to the interruption.
[0323] The control plan for operating the functional block 115 of
the electric device 101 and charging the rechargeable battery 211
is created by the flowcharts described above, and executed. This
control plan is described using FIGS. 24A to 24D.
[0324] FIG. 24A is a diagram showing an example of the control plan
obtained when the charging start time overlaps with the operating
time frame. FIG. 24B is a diagram showing an example of a control
plan obtained when the charging ending time overlaps with the
operating time frame. FIG. 24C is a diagram showing an example of a
control plan obtained when the operating time frame is shifted
forward in front of the charging time frame. FIG. 24D is a diagram
showing an example of a control plan obtained when the operating
time frame is shifted behind the charging time frame.
[0325] As shown in FIG. 24A, when the estimated return time of the
electric car 201 is acquired as the charging start time of the
electric car 201, in some cases the charging start time overlaps
with the operating time slot in which the electric device 101 is
scheduled to be operated. When a total of the power required to
charge the rechargeable battery and the power used for operating
the electric device 101 does not exceed the predetermined value
(allowable power), charging of the rechargeable battery 211 and the
operation of the electric device 101 can be performed at the same
time. However, when the power required to charge the rechargeable
battery 211 is so large that the total power usage exceeds the
allowable power, the time frame adjustment needs to be
performed.
[0326] As shown in FIG. 24B, the time frame required for charging
the rechargeable battery, which is, in other words, the charging
start time and the charging ending time, can be obtained by
acquiring the information pertaining to the necessary charge amount
of the rechargeable battery 211 along with the estimated return
time of the electric car 201. In some cases the charging ending
time overlaps with the operating time slot in which the electric
device 101 is scheduled to be operated. As with FIG. 24A, when the
total of the power required to charge the rechargeable battery and
the power used for operating the electric device 101 does not
exceed the predetermined value (allowable power), charging of the
rechargeable battery 211 and the operation of the electric device
101 can be performed at the same time. However, when the power
required to charge the rechargeable battery 211 is so large that
the total power usage exceeds the allowable power, the time frame
adjustment needs to be performed.
[0327] When the priority for charging the electric car 201 is
higher than the priority for operating the electric device 101, the
time frame adjusting unit 120 shifts the operating time frame of
the electric device 101 forward in front of the charging time frame
of the rechargeable battery 211 so that the operating time frame of
the electric device 101 does not overlap with the charging time
frame, as shown in FIG. 24C. Furthermore, the time frame adjusting
unit 120 shifts the operating time frame of the electric device 101
behind the charging time frame of the rechargeable battery 211 so
that the operating time frame of the electric device 101 does not
overlap with the charging time frame, as shown in FIG. 24D.
[0328] On the other hand, although not illustrated in the diagrams,
when the priority for operating the electric device 101 is higher
than the priority for charging the electric car 201, the time frame
adjusting unit 120 shifts the charging start time so that the
electric car 201 is charged after the end of the operation of the
electric device 101.
[0329] In some cases a programmed operation of the electric device
101 is performed during the lowest electricity rate time slot. This
means that the control plans shown in FIGS. 24C and 24D need to
take the time-slot differentiated electricity rate information into
consideration. These control plans are described with reference to
FIGS. 25A to 25C.
[0330] FIG. 25A is a diagram showing an example of a control plan
obtained when the operating time frame is shifted forward to the
front of the charging time frame. FIG. 25B is a diagram showing an
example of a control plan obtained when the operating time frame is
shifted behind the charging time frame. FIG. 25C is a diagram
showing an example of a control plan obtained when operation of the
electric device is started at a start time of the lowest
electricity rate time slot and ended prior to the charging time
frame.
[0331] In FIG. 25A, the operating time frame of the electric device
101 is shifted forward to the front of the charging time frame.
However, the operating time frame of the electric device 101 and
the charging time frame of the rechargeable battery 211 fall within
the lowest electricity rate time slot. In FIG. 25B, on the other
hand, the operating time frame of the electric device 101 is
shifted behind the charging time frame, but the operating time
frame of the electric device 101 is past the lowest electricity
rate time slot. On the contrary, when the operating time frame of
the electric device 101 is shifted forward to the front of the
charging time frame, the operating time frame does not fall within
the lowest electricity rate time slot. When the operating time
frame of the electric device 101 is shifted behind the charging
time frame, the operating time frame might fall within the lowest
electricity rate time slot.
[0332] This is determined by the operating time frame of the
electric device 101, and the charging time frame and the estimated
return time of the electric car 201. In the past, the control plans
for operating the electric car and charging the battery were
created after the return of the electric car, because the estimated
return time was not obtained. Therefore, the options in the past
were to operate the electric device 101 after the electric car
returns to the house and the charging is performed, or to charge
the battery after the end of the operation of the electric device
101. In other words, there was no option where the electric device
101 is operated prior to the return of the electric car.
[0333] Moreover, the time frame adjusting unit 120 according to the
present embodiment can create both of the control plans shown in
FIGS. 25A and 25B and select the lowest electricity rate from these
two control plans. This provides the effect of creating a control
plan after the estimated return time is obtained.
[0334] In addition, as shown in FIG. 25C, the time frame adjusting
unit 120 acquires the estimated return time at a current time prior
to the start time (11 p.m.) of the lowest electricity rate time
slot. When the operation of the electric device 101 can be started
and ended between 11 p.m. and the return of the electric car, the
time frame adjusting unit 120 shifts the scheduled operation start
time of the electric device 101 such that the operation of the
electric device 101 is started from 11 p.m. In this manner, because
the operation of the electric device 101 is already ended by the
time the electric car returns to the house, the current required to
charge the rechargeable battery 211 or the charging time frame of
the rechargeable battery 211 do not affect the operation of the
electric device 101.
[0335] FIG. 26A is a diagram showing an example of a control plan
obtained when the operating time frame of the electric device
passes the lowest electricity rate time slot as a result of
shifting the operating time frame forward to the front of the
charging time frame. FIG. 26B is a diagram showing an example of a
control plan obtained after the operating time frame and the
charging time frame are shifted back from the state shown in FIG.
26A. FIG. 26C is a diagram showing an example of a control plan
obtained when the operating time frame of the electric device is
segmented.
[0336] As shown in FIG. 26A, when the operating time frame of the
electric device 101 is shifted forward to the front of the charging
time frame, the operation start time of the electric device 101
might protrude forward from the lowest electricity rate time slot.
In such a case, as shown in FIG. 26B the time frame adjusting unit
120 shifts the operating time frame of the electric device 101 and
the charging time frame of the rechargeable battery 211 backward in
a manner as to wait for the start time of the lowest electricity
rate time slot to start operating the electric device 101, and
charge the rechargeable battery 211 after the end of the operation
of the electric device 101. As a result, a low electricity rate can
be obtained.
[0337] In other words, when the operation start time protrudes
forward from the lowest electricity rate time slot as a result of
shifting the operating time frame of the electric device 101
forward to the front of the charging time frame, the time frame
adjusting unit 120 delays the operation start time by the length of
the protruding time frame. Then, the time frame adjusting unit 120
determines whether or not the operating time frame between the
operation start time and the operation ending time and the charging
time frame between the charging start time and the charging ending
time fall within the lowest electricity rate time slot, in a case
where the operation of the electric device 101 is started at the
start time of the lowest electricity rate time slot. When the
operating time frame and the charging time frame fall within the
lowest electricity rate time slot, the time frame adjusting unit
120 creates a control plan based on the operating time frame and
the charging time frame.
[0338] Here, in some cases the operation end time of the electric
device 101 is past the estimated return time. This delays the
charging start time. Therefore, when the abovementioned time frame
adjusting is performed, the time frame adjusting unit 120 notifies
the passenger of the electric car 201 of the charging start time,
by transmitting the charging start time to the communication unit
215 of the electric car 201 via the communication unit 112 and
displaying the charging start time on the navigation unit 214 (step
S63 of FIG. 22).
[0339] Although not illustrated, when the operating time frame
between the operation start time and the operation ending time of
the electric device 101 and the charging time frame between the
charging start time and the charging ending time do not fall within
the lowest electricity rate time slot even after the abovementioned
time frame adjustment is performed, the time frame adjusting unit
120 may allow the passenger of the electric car 201 to confirm the
operation start time, the operation ending time, the charging start
time, and the charging ending time, by transmitting the operation
start time of the electric device 101, the operation ending time of
the electric device 101, the charging start time of the
rechargeable battery 211 and the charging ending time of the
rechargeable battery 211, to the communication unit 215 of the
electric car 201 via the communication unit 112, and then
displaying the operation start time, the operation ending time, the
charging start time and the charging ending time, on the navigation
unit 214.
[0340] Alternatively, the time frame adjusting unit 120 may create
a plurality of control plans for the operation start time of the
electric device 101, the operation ending time for the electric
device 101, the charging start time of the rechargeable battery
211, and the charging ending time of the rechargeable battery 211,
and allow the passenger of the electric car 201 to select any of
the control plans, by transmitting the plurality of control plans
to the communication unit 215 of the electric car 201 via the
communication unit 112 and displaying the plurality of control
plans on the navigation unit 214.
[0341] Moreover, as shown in FIG. 26C, the rechargeable battery 211
can be charged after temporarily stopping the operation of the
electric device 101, and then the operation of the electric device
101 can be started again after the end of the charging. Not all
types of the electric device 101 can be stopped temporarily.
However, for example, when the electric device 101 is an electric
water heater, the operation thereof can be stopped in the middle of
its boiling operation. When the electric device 101 is a clothes
washer/dryer, the operation thereof can be stopped after a drying
process is performed to an extent after rinsing and spin
processes.
[0342] As described above, the time frame adjusting unit 120 not
only can create a control plan based on a unit of a time frame
between the start and the end of the operation of the electric
device 101, but also can create a control plan based on a unit of a
time frame between the operation undergoing in the electric device
101 and operation at above the predetermined value.
[0343] For instance, when the electric device 101 is a clothes
washer/dryer, a washing process, a rinsing process, a spin process,
and a certain amount of drying process are performed in one unit of
time frame, and the rest of the drying process is performed in one
unit of time frame.
[0344] When the electric device 101 is, for example, a dish
washer/dryer, a dish washing process and a rinsing process are
performed as one unit of time frame, and a dish drying process is
performed in one unit of time frame.
[0345] Regarding the charging of the rechargeable battery 211, a
control plan thereof may be created in two steps of one unit time
frame in which the rechargeable amount reaches the predetermined
value (e.g., charging 75% when the constant current charging mode
is completed) and one unit time frame in which the rechargeable
amount is the remaining 25%, instead of creating a control plan
with one unit time frame alone in which the rechargeable amount is
100%.
[0346] In this manner, when the operation of the electric device
101 can be started by the estimated return time and ended at the
point above the predetermined value (e.g., in one unit or two
units), the time frame adjusting unit 120 adjusts the operating
time frame so that the operation of more than the predetermined
value can be ended by the estimated arrival time. Accordingly, the
operation of the electric device 101 can be segmented to make a
control plan thereof, increasing the flexibility of the plan.
[0347] Note that, as shown in FIGS. 24C, 25A and 25C, when the
operating time frame of the electric device 101 becomes longer than
expected (e.g., when it takes longer to dry clothes in the clothes
washer/dryer) as a result of shifting the operating time frame of
the electric device 101 forward to the front of the charging time
frame, the operation ending time of the electric device 101 becomes
likely to pass the estimated return time, thereby delaying the
charging start time. The time frame adjusting unit 120, therefore,
inform the passenger of the electric car 201 of the charging start
time by transmitting the charging start time to the communication
unit 215 of the electric car 201 via the communication unit 112 and
then displaying the charging start time on the navigation unit 214
(step S63 of FIG. 22).
[0348] Note that, as shown in FIGS. 25A to 25C and FIGS. 26A to
26C, a scheduled time of use of the electric car 201 or a scheduled
time of use of the electric water heater may be provided
independently from the lowest electricity rate time slot, and
conditions of a completion time limit for completing the charging
of the electric car 201 or the boiling of the electric water heater
by the scheduled time of use may be added to the abovementioned
control plan. The time frame adjusting unit 120 creates a control
plan before the completion time limit. Furthermore, when there is a
problem with the control plan, the user or the passenger is
informed of the problem via the user instructing unit 124 or the
navigation unit 214.
[0349] The control plan creation process of step S60 shown in FIG.
22 is further described next.
[0350] FIGS. 27 and 28 are flowcharts for illustrating the control
plan creation process of step S60 shown in FIG. 22.
[0351] First, in step S71, the time frame adjusting unit 120
creates a control plan for operating the functional block 115 of
the electric device 101 and for charging the rechargeable battery
211, on the basis of the acquired scheduled operation start time
and scheduled operation ending time of the functional block 115 of
the electric device 101 and the estimated return time and the
necessary charge amount of the rechargeable battery 211 that needs
to be charged at the time of return home, which are included in the
acquired charge information. The time frame adjusting unit 120
takes the estimated return time as the charging start time,
computes a charging time frame Ty required to charge the
rechargeable battery 211, on the basis of the necessary charge
amount of the rechargeable battery 211 that needs to be charged at
the time of return home, and computes the charging ending time by
adding the computed charging time frame to the charging start
time.
[0352] In the subsequent step S72, the time frame adjusting unit
120 refers to the created control plan to determine whether or not
the functional block 115 of the electric device 101 is scheduled to
be operated within the charging time frame Ty.
[0353] FIG. 29 is a diagram showing an example of the operating
time frame and the charging time frame according to Embodiment 5 of
the present invention. As shown in FIG. 29, the charging is started
at the estimated return time, and an operating time frame Tx and
the charging time frame Ty of the functional block 115 of the
electric device 101 overlap with each other. Moreover, the
operating time frame Tx and the charging time frame Ty fall within
a lowest electricity rate time slot Tz. The operation start time
starts later than a start time ta of the lowest electricity rate
time slot Tz, and the charging ending time starts earlier than an
ending time tb of the lowest electricity rate time slot Tz. For
example, the time frame adjusting unit 120 determines whether or
not the functional block 115 of the electric device 101 is
scheduled to be operated within the charging time frame Ty, by
determining whether the operation ending time starts later than the
estimated return time or not.
[0354] When it is determined that the functional block 115 of the
electric device 101 is scheduled to be operated within the charging
time frame Ty (NO in step S72), no changes need to be made to the
created control plan. Thus, the control plan creation process is
ended, and the time frame adjusting unit 120 moves to step S61
shown in FIG. 22.
[0355] However, when it is determined that the functional block 115
of the electric device 101 is scheduled to be operated within the
charging time frame Ty (YES in step S72), in step S73 the time
frame adjusting unit 120 determines whether a total power usage of
the power used for operating the functional block 115 of the
electric device 101 and the power used for charging the
rechargeable battery 211 is greater than the allowable power. Note
that the total power usage is computed in step S58 shown in FIG.
22. When it is determined that the total power usage is equal to or
lower than the allowable power (NO in step S73), no changes need to
be made to the created control plan. Thus, the control plan
creation process is ended, and the time frame adjusting unit 120
moves to step S61 shown in FIG. 22.
[0356] However, when it is determined that the total power usage is
greater than the allowable power (YES in step S73), in step S74 the
time frame adjusting unit 120 determines whether a time frame T2
between the start time ta of the lowest electricity rate time slot
Tz and the estimated return time is longer than the operating time
frame Tx. When it is determined that the time frame T2 between the
start time ta of the lowest electricity rate time slot Tz and the
estimated return time is longer than the operating time frame Tx
(YES in step S74), in step S75 the time frame adjusting unit 120
changes the control plan in a manner as to bring the operating time
frame Tx forward, such that the operating time frame Tx falls
within the lowest electricity rate time slot Tz without overlapping
with the charging time frame Ty. In other words, the time frame
adjusting unit 120 brings the scheduled operation start time of the
functional block 115 of the electric device 101 forward to the
start time ta of the lowest electricity rate time slot Tz.
[0357] FIG. 30 is a diagram showing an example of the operating
time frame and the charging time frame obtained when the operating
time frame is brought forward. As shown in FIG. 30, the operation
of the functional block 115 of the electric device 101 is started
at the start time ta of the lowest electricity rate time slot Tz,
and the operating time frame Tx and the charging time frame Ty do
not overlap with each other. Moreover, the operating time frame Tx
and the charging time frame Ty fall within the lowest electricity
rate time slot Tz.
[0358] Note that, in the present embodiment, the scheduled
operation start time of the functional block 115 of the electric
device 101 matches the start time ta of the lowest electricity rate
time slot Tz, but the present invention is not limited to this
configuration. The scheduled operation start time of the functional
block 115 of the electric device 101 may start later than the start
time ta of the lowest electricity rate time slot Tz, as long as the
operating time frame Tx and the charging time frame Ty do not
overlap with each other. For example, the time frame adjusting unit
120 may bring the operation start time forward, such that the
scheduled operation ending time of the functional block 115 of the
electric device 101 matches the estimated return time.
[0359] When it is determined that the time frame T2 between the
start time ta of the lowest electricity rate time slot Tz and the
estimated return time is equal to or shorter than the operating
time frame Tx (NO in step S74), in step S76 the time frame
adjusting unit 120 determines whether a time frame T3 between the
charging ending time and the ending time tb of the lowest
electricity rate time slot Tz is longer than the operating time
frame Tx. When it is determined that the time frame T3 between the
charging ending time and the ending time tb of the lowest
electricity rate time slot Tz is longer than the operating time
frame Tx (YES in step S76), in step S77 the time frame adjusting
unit 120 changes the control plan in a manner as to bring the
operating time frame Tx backward, such that the operating time
frame Tx falls within the lowest electricity rate time slot Tz
without overlapping with the charging time frame Ty. In other
words, the time frame adjusting unit 120 brings the scheduled
operation start time of the functional block 115 of the electric
device 101 backward to the charging ending time. In this manner,
the time frame adjusting unit 120 changes the control plan such
that the functional block 115 of the electric device 101 is
operated after the end of the charging.
[0360] FIG. 31 is a diagram showing an example of the operating
time frame and the charging time frame obtained before the
operating time frame is brought backward. FIG. 32 is a diagram
showing an example of the operating time frame and the charging
time frame obtained after the operating time frame is brought
backward.
[0361] As shown in FIG. 31, the charging is started at the
estimated return time, and the operating time frame Tx and the
charging time frame Ty of the functional block 115 of the electric
device 101 overlap with each other. The time frame T3 between the
charging ending time and the ending time tb of the lowest
electricity rate time slot Tz is longer than the operating time
frame Tx.
[0362] Also, as shown in FIG. 32, the operation of the functional
block 115 of the electric device 101 is started at the charging
ending time, and the operating time frame Tx and the charging time
frame Ty do not overlap with each other. The operating time frame
Tx and the charging time frame Ty fall within the lowest
electricity rate time slot Tz.
[0363] Note that, in the present embodiment, the scheduled
operation start time of the functional block 115 of the electric
device 101 matches the charging ending time, but the present
invention is not limited to this configuration. The scheduled
operation start time of the functional block 115 of the electric
device 101 may start later than the charging ending time, as long
as the operating time frame Tx falls within the lowest electricity
rate time slot Tz without overlapping with the charging time frame
Ty. For example, the time frame adjusting unit 120 may bring the
operation start time backward, such that the scheduled operation
ending time of the functional block 115 of the electric device 101
matches the ending time tb of the lowest electricity rate time slot
Tz.
[0364] On the other hand, when it is determined that the time frame
T3 between the charging ending time and the ending time tb of the
lowest electricity rate time slot Tz is equal to or shorter than
the operating time frame Tx (NO in step S76), in step S78 the time
frame adjusting unit 120 changes the control plan in a manner as to
bring the operating time frame Tx forward, so that the operating
time frame Tx and the charging time frame Ty do not overlap with
each other. In other words, the time frame adjusting unit 120
brings the operating time frame Tx forward such that the scheduled
operation ending time of the functional block 115 of the electric
device 101 matches the estimated return time.
[0365] FIG. 33 is a diagram showing an example of the operating
time frame and the charging time frame obtained before the
operating time frame is brought forward. FIG. 34 is a diagram
showing an example of the operating time frame and the charging
time frame obtained after the operating time frame is brought
forward.
[0366] As shown in FIG. 33, the charging is started at the
estimated return time, and the operating time frame Tx and the
charging time frame Ty of the functional block 115 of the electric
device 101 overlap with each other. Moreover, the time frame T2
between the start time to of the lowest electricity rate time slot
Tz and the estimated return time is equal to or shorter then the
operating time frame Tx, and the time frame T3 between the charging
ending time and the ending time tb of the lowest electricity rate
time slot Tz is equal to or shorter than the operating time frame
Tx.
[0367] As shown in FIG. 34, the charging is started after the end
of the operation of the functional block 115 of the electric device
101, and the operating time frame Tx and the charging time frame Ty
do not overlap with each other. Furthermore, the charging time
frame Ty falls within the lowest electricity rate time slot Tz, but
the operating time frame Tx does not fall within the lowest
electricity rate time slot Tz.
[0368] In the subsequent step S79, the time frame adjusting unit
120 determines whether or not a time frame T4 between the scheduled
operation start time of the functional block 115 of the electric
device 101 and the start time ta of the lowest electricity rate
time slot Tz is shorter than a predetermined allowed time frame.
Note that the allowed time frame is a time frame for waiting for
the start of the charging after the electric car returns to the
house, and is set previously by the user.
[0369] Here, when it is determined that the time frame T4 between
the scheduled operation start time of the functional block 115 of
the electric device 101 and the start time ta of the lowest
electricity rate time slot Tz is shorter than the predetermined
allowed time frame (YES in step S79), the time frame adjusting unit
120 changes the control plan in a manner as to delay the scheduled
operation start time and the scheduled charging start time by the
time frame T4.
[0370] FIG. 35 is a diagram showing an example of the operating
time frame and the charging time frame obtained after the operating
time frame and the charging time frame are brought backward.
[0371] As shown in FIG. 35, the scheduled operation start time and
the scheduled charging start time are brought backward by the time
frame T4. Especially the scheduled charging start time is behind
the estimated return time by the time frame T4. In other words, the
operation of the functional block 115 of the electric device 101 is
started at the start time ta of the lowest electricity rate time
slot Tz, and the charging of the rechargeable battery 211 is
started after the end of the operation of the functional block 115
of the electric device 101, the time frame T4 behind the estimated
return time. The operating time frame Tx and the charging time
frame Ty do not overlap with each other. The operating time frame
Tx and the charging time frame Ty fall within the lowest
electricity rate time slot Tz.
[0372] When it is determined that the time frame T4 between the
scheduled operation start time of the functional block 115 of the
electric device 101 and the start time ta of the lowest electricity
rate time slot Tz is equal to or longer than the predetermined
allowed time frame (NO in step S79), in step S81 the time frame
adjusting unit 120 determines whether or not a time frame T1
between a current time and the estimated return time is longer than
the operating time frame Tx.
[0373] When it is determined that the time frame T1 between the
current time and the estimated return time is longer than the
operating time frame Tx (YES in step S81), no changes need to be
made to the control plan. Thus, the time frame adjusting unit 120
moves to step S61 shown in FIG. 22.
[0374] FIG. 36 is a diagram showing an example of the operating
time frame and the charging time frame obtained when the time frame
T1 between the current time and the estimated return time is longer
than the operating time frame Tx after the operating time frame is
brought forward.
[0375] As shown in FIG. 36, the time frame T1 between the current
time and the estimated return time is longer than the operating
time frame Tx. The charging is started after the end of the
operation of the functional block 115 of the electric device 101,
and the operating time frame Tx and the charging time frame Ty do
not overlap with each other. Moreover, the charging time frame Ty
falls within the lowest electricity rate time slot Tz, but the
operating time frame Tx does not fall within the lowest electricity
rate time slot Tz.
[0376] In this case, the functional block 115 of the electric
device 101 can utilize a part of the lowest electricity rate time
slot Tz. In addition, because the operation of the functional block
115 of the electric device 101 is ended at the time of return home,
the charging can be started immediately after the return home.
[0377] However, when it is determined that the time frame T1
between the current time and the estimated return time is equal to
or shorter than the operating time frame Tx (NO in step S81), in
step S82 the time frame adjusting unit 120 changes the control plan
in a manner as to operate the functional block 115 of the electric
device 101 after the charging. When the time frame T1 between the
current time and the estimated return time is equal to or shorter
than the operating time frame Tx, the functional block 115 of the
electric device 101 cannot be operated prior to the start of the
charging. Therefore, when the time frame T1 between the current
time and the estimated return time is equal to or shorter than the
operating time frame Tx, the functional block 115 of the electric
device 101 is operated after the charging is performed.
[0378] FIG. 37 is a diagram showing an example of the operating
time frame and the charging time frame obtained when the time frame
T1 between the current time and the estimated return time is equal
to or shorter than the operating time frame Tx and when the
operating time frame is brought backward.
[0379] As shown in FIG. 37, the time frame T1 between the current
time and the estimated return time is equal to or shorter than the
operating time frame T1. The operation of the functional block 115
of the electric device 101 is started after the end of the charging
of the rechargeable battery 211, and the operating time frame Tx
and the charging time frame Ty do not overlap with each other. In
addition, although the charging time frame Ty falls within the
lowest electricity rate time slot Tz, the operating time frame Tx
does not fall within the lowest electricity rate time slot Tz.
[0380] Note that, as shown in FIG. 37, when the functional block
115 of the electric device 101 is operated beyond the ending time
tb of the of the lowest electricity rate time slot Tz, the time
frame adjusting unit 120 may inquire whether to continue the
operation or not.
[0381] Moreover, the time frame adjusting unit 120 may compare the
length of the time frame between the start time to of the lowest
electricity rate time slot Tz and the estimated return time, with
the length of the time frame between the charging ending time and
the ending time tb of the lowest electricity rate time slot Tz, to
shift the operating time frame Tx toward the longer time frame.
[0382] In FIGS. 24 to 26 and FIGS. 29 to 37, the power consumed in
the operation of the functional block 115 of the electric device
101 and the power consumed in the charging are shown in rectangular
shapes. In actuality, however, because these consumed powers change
with time, they do not necessarily form rectangular shapes. When
the power consumed by the functional block 115 of the electric
device 101 lowers and does not exceed the allowable power even when
the operation of the functional block 115 of the electric device
101 is performed at the same time with the charging, the charging
may be started prior to the end of the operation of the functional
block 115 of the electric device 101.
[0383] Moreover, the lowest electricity rate time slot may be not
only a predetermined time slot (e.g., 11 p.m. to 7 a.m.), but also
a lowest electricity time slot of a certain day that is acquired
from a server and provided by a power company.
[0384] When the power control system has a solar power generation
system or a fuel cell, the lowest electricity rate time slot may be
a time slot producing a surplus amount of generated power, which
is, for example, between 9 a.m. and 4 p.m. on a sunny day.
[0385] In the present embodiment, the control plan is created in
the lowest electricity rate time slot. However, when it is
difficult to create the control plan within this time frame, the
control plan is created in consideration of a second lowest
electricity rate time slot as well. For instance, in FIG. 20, when
it is difficult to create the control plan in the time slot between
11 p.m. and 7 a.m. (when the electricity rate is 9 yen or lower), a
time slot between 7 a.m. and 10 a.m. and a time slot between 5 p.m.
and 11 p.m. (when the electricity rate is 23 yen or lower) are
included in the aforementioned time slot.
[0386] Generally, when a plurality of time slots (at least two)
with different electricity rates are present, the control plan is
created first in the lowest electricity rate time slot. When it is
difficult to operate the electric device and charge the electric
car during the lowest rate time slot, the control plan is created
in consideration of the second lowest electricity rate time slot as
well. When doing so is difficult, the control plan is created in a
third lowest electricity rate time slot as well. Subsequently, the
number of low electricity rate time slots is increased, and
eventually the control plan is created in the highest electricity
rate time slot.
[0387] In this manner, a predetermined value is set between the
highest electricity rate and the lowest electricity rate, and time
slot in which the electricity rate is equal to or lower than the
predetermined value is selected, and then the power supply start
time of supplying power to the electric device and the charging
start time of charging the rechargeable battery are determined.
[0388] Note that the predetermined value can be (1) a value lower
than the highest electricity rate, (2) a value that is equal to or
lower than x% of the highest electricity rate, (3) a value lower
than the top y of the rates from the highest electricity rate to
the lowest electricity rate, etc.
[0389] When the electricity rates of the time slots fluctuate, the
predetermined value is determined with reference to the electricity
rates between the current electricity rate and future electricity
rates (e.g., electricity rates obtained in 24 hours). When no
future electricity rates are obtained, the predetermined value is
determined with reference to the past electricity rates (e.g., the
electricity rates obtained in the last 24 hours). Needless to say,
the predetermined value may be determined with reference to both
the future electricity rates and the past electricity rates.
[0390] Note that the present embodiment describes one electric
device and one electric vehicle for the sake of explanatory
convenience, but the effects of the present invention can be
realized with the combinations described above, even with a
plurality of electric devices to be operated and a plurality of
rechargeable batteries to be charged. Moreover, the present
embodiment describes the operation of the electric device and the
charging of the electric vehicle, but the effects of the present
invention can be realized when creating control plans using a
plurality of electric vehicles without using the electric
device.
[0391] In the power control system that has the server device for
mediating the information communication between the charger and the
electric vehicle, not only is it possible to cause the server
device to compute the time of arrival at the location where the
charger is present and the remaining level of the on-board battery,
but also part or all of the flowcharts shown in FIGS. 22, 27 and 28
can be performed by the server device.
Embodiment 6
[0392] Next, Embodiment 6 of the present invention is described.
Note that in Embodiment 6 the same configurations as those of
Embodiment 5 are denoted with the same reference numerals as those
of Embodiment 5, and, therefore, detailed descriptions thereof are
omitted.
[0393] In Embodiment 5, the electric device has the charger, but
the charger and the electric device are not necessarily
integrated.
[0394] FIG. 38 is a block diagram showing an example of a
configuration of a power control system according to Embodiment 6
of the present invention. The power control system shown in FIG. 38
has the electric device 107, the ampere breaker 105, the branch
breakers 106, 108, the total power usage detector 114, the electric
car 201, and a charger 131.
[0395] As shown in FIG. 38, the charger 131 has a charging
functional block (the charging unit 113, the charge control unit
118, the second power usage detector 119 and the like shown in FIG.
18) and the time frame adjusting unit 120. The charger 131 has the
connecting unit 111, the charging unit 113, the charge control unit
118, the second power usage detector 119, the time frame adjusting
unit 120, the user instructing unit 124, the first communication
unit 132, and the second communication unit 133. The electric
device 107 has an equipment control block (the functional block
115, the electric device control unit 116, the first power usage
detector 117 and the like shown in FIG. 18), which is not shown.
The total power usage detector 114 is disposed on the downstream
side of the ampere breaker 105.
[0396] The first communication unit 132 has the same functions as
the communication unit 112 shown in FIG. 18.
[0397] The second communication unit 133 receives power usage
values from the electric device 107 and the total power usage
detector 114, and transmits a control signal for controlling
operation of the electric device 107, from the charger 131 to the
electric device 107. Note that the total power usage detector 114
has a communication unit for transmitting the power usage value to
the charger 131. The electric device 107 has a communication unit
that transmits the power usage value to the charger 131 and
receives the control signal for controlling the operation of the
electric device 107, from the charger 131.
[0398] Note that, in Embodiment 6, the electric device 107
corresponds to an example of the electric device, the charger 131
to an example of the power control device, and the first
communication unit 132 to an example of the receiver.
[0399] In Embodiment 6, the charger 131 is operated based on the
flowcharts shown in FIGS. 22, 27 and 28 described in Embodiment 5.
Processes that are different than the processes shown in FIGS. 22,
27 and 28 of Embodiment 5 are described hereinafter.
[0400] In step S58, in a method for estimating a total power usage,
the time frame adjusting unit 120 acquires, via the communication
unit 133, a power usage value detected by the first power usage
detector of the electric device 107 (or a past power usage value
stored in the first power usage detector, or a power usage value
predicted by the first power usage detector), and estimates a total
power usage obtained by adding a power usage value detected by the
second power usage detector 119 (or actual values of past power
usage values stored in the second power usage detector 119, or a
power usage value predicted by the second power usage detector 119)
to the acquired power usage of the electric device 107 obtained
during the operation thereof. The time frame adjusting unit 120 may
acquire, through the communication unit 133, a power usage value
detected by the total power usage detector 114 (or actual values of
past power usage values stored in the total power usage detector
114, or a power usage value predicted by the total power usage
detector 114), and use the acquired power usage value as a total
power usage.
[0401] In step S65, the time frame adjusting unit 120 sends a
created control plan to the charge control unit 118 and to the
electric device control unit of the electric device 107 via the
communication unit 133. The charge control unit 118 charges the
rechargeable battery 211 based on the control plan, and the
electric device control unit operates the electric device 107 based
on the control plan.
[0402] In step S73, the time frame adjusting unit 120 takes power
(contract power) of the ampere breaker 105 as allowable power and
compares this allowable power with the total power usage.
[0403] In Embodiment 6, processes other than those described above
are same as those of Embodiment 5.
[0404] Note that the present embodiment describes one electric
device and one electric vehicle for the sake of explanatory
convenience, but the effects of the present invention can be
realized with the combinations described above, even with a
plurality of electric devices to be operated and a plurality of
rechargeable batteries to be charged. Moreover, the present
embodiment describes the operation of the electric device and the
charging of the electric vehicle, but the effects of the present
invention can be realized when creating control plans using a
plurality of electric vehicles without using the electric
device.
[0405] Embodiments 5 and 6 have the following effects.
[0406] (1) The information pertaining to the estimated arrival time
is acquired from the electric vehicle, and, because the operation
start time of the electric device and the charging start time of
the rechargeable battery are adjusted after the estimated arrival
time such that the total of the power required to charge the
rechargeable battery and the power used for operating the other
electric device does not exceed the predetermined value, the
control plan can be created prior to the arrival of the electric
vehicle, and the created plan can be executed.
[0407] (2) The information pertaining to the estimated arrival time
and the necessary charge amount of the rechargeable battery is
acquired, and, because the operation start time of the electric
device and the charging start time of the rechargeable battery are
adjusted such that the total of the power required to charge the
rechargeable battery and the power used for operating the other
electric device does not exceed the predetermined value during a
time frame between the charging start time and the charging ending
time, the control plan can be created prior to the arrival of the
electric vehicle, and the created plan can be executed.
[0408] (3) The time frame adjusting unit acquires the information
pertaining to the necessary charge amount, determines whether to
prioritize the charging of the rechargeable battery or to
prioritize the operation of the electric device, and adjusts the
operation start time of the electric device and the charging start
time of the rechargeable battery. Therefore, prior to the arrival
of the electric vehicle, the priority order of the rechargeable
battery and the electric device is determined and the control plan
is created, whereby the created control plan can be executed.
[0409] (4) The information pertaining to the estimated arrival time
is computed after the current position of the electric vehicle is
acquired and based on the distance between the acquired current
position and the point where the charger is present, as well as the
moving speed of the electric vehicle and the current time.
Therefore, the information pertaining to the estimated arrival time
can be calculated by acquiring the current position of the electric
vehicle by using a GPS device or the navigation device mounted in
the electric vehicle.
[0410] (5) The information pertaining to the necessary charge
amount of the rechargeable battery obtained at the time of the
arrival at the point where the charger is present, is computed
after the current position of the electric vehicle is acquired and
based on the distance between the acquired current position and the
point where the charger is present, as well as the electricity
energy amount used for moving the electric vehicle and the current
charge amount of the rechargeable battery. Therefore, the
information pertaining to the necessary charge amount of the
rechargeable battery can be calculated by acquiring the current
position of the electric vehicle by using the GPS device or the
navigation device mounted in the electric vehicle.
[0411] (6) The timing when the charger acquires the information on
the estimated arrival time from the electric vehicle includes at
least one of: the time when the destination is set to the location
where the charger is present (the location where power is supplied
to the electric vehicle); the time when the electric vehicle starts
moving toward the destination; and the time when the electricity
rate changes. Since the estimated arrival time is transmitted to
the charger at this timing, the control plan can be created at
optimal timing, and the created control plan can be executed.
[0412] (7) Because the electric vehicle is informed of a delay of
the charging start time, the passenger of the electric vehicle can
adjust the arrival time.
[0413] (8) The electric device is operated in a plurality of
operation units. When the electric device can be operated in a
predetermined operation unit after the arrival of the electric
vehicle and before the charging is started, the operation of the
electric device in the predetermined operation unit can be ended
prior to the end of the charging of the rechargeable battery.
[0414] (9) The control plan for the charging and the operation can
be created such that the charging time frame and the operating time
frame fall within the lowest electricity rate time slot, and the
created control plan can be executed.
[0415] (10) The charging of the rechargeable battery and the
operation of the electric device can be performed at a low
electricity rate.
[0416] (11) When delaying the charging start time of the
rechargeable battery in order to charge the rechargeable battery
and operate the electric device at a low electricity rate, the
electric vehicle is informed of such delay of the charging start
time, which allows the passenger of the electric car to adjust the
arrival time.
[0417] (12) When the operation ending time of the electric device
gets behind the estimated arrival time, the electric vehicle is
informed of the fact that the operation ending time (the charging
start time) is delayed. Therefore, the passenger of the electric
vehicle can adjust the arrival time.
[0418] (13) Because the connecting unit that connects the charger
and the electric vehicle is provided outside the electric device, a
charging facility can be established simply, without requiring any
major electric construction (e.g., a construction for adding more
distribution boards, a wiring construction between a distribution
board and the outside, an installation construction for installing
a charge outlet outside, etc.).
[0419] (14) The calculation of the estimated arrival time and the
calculation of the necessary charge amount of the rechargeable
battery are performed by the charger, the electric vehicle, or the
server mediating the information communication between the charger
and the electric vehicle. Therefore, the electric vehicle may
calculate the estimated arrival time and the necessary charge
amount of the rechargeable battery, and the result of the
calculation may be transmitted to the charger. Moreover, the
information on the current position and the like may be transmitted
from the electric vehicle to the charger, and the charger may
calculate the estimated arrival time and the necessary charge
amount of the rechargeable battery. In addition, the information on
the current position and the like may be transmitted from the
electric vehicle to the server, and the server may calculate the
estimated arrival time and the necessary charge amount of the
rechargeable battery, and then the result of the calculation may be
transmitted to the charger.
[0420] In the charger used in a household, a business office, or a
factory, the control plan for operating the other electric device
and charging the rechargeable battery can be created and executed
prior to the arrival of the electric car, by acquiring the
estimated arrival time from the electric car in use.
[0421] Note that Embodiments 1 to 6 describe the electric cars as
the examples of the electric vehicle, but the present invention is
not particularly limited to such embodiments. The electric vehicle
may be a plug-in hybrid vehicle, a two-wheeled electric vehicle, an
electric bicycle, or other vehicle that travels using
electricity.
[0422] The specific embodiments described above mainly include the
inventions having the following configurations.
[0423] A power control system according to one aspect of the
present invention is a power control system that has an electric
vehicle and a power control device that controls charging of a
rechargeable battery of the electric vehicle and controls supply of
power to an electric device, wherein the electric vehicle includes:
the rechargeable battery; a charge information acquiring unit that
acquires charge information pertaining to the charging of the
rechargeable battery; and a transmitter that transmits the charge
information acquired by the charge information acquiring unit,
prior to the arrival of the electric vehicle at a location where
power is supplied to the electric vehicle, and wherein the power
control device includes: a receiver that receives the charge
information transmitted by the transmitter, prior to the arrival of
the electric vehicle at the location where power is supplied to the
electric vehicle; and a power control unit that determines a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery, on the
basis of the charge information received by the receiver, such that
the supply of power to the electric device and the charging of the
rechargeable battery are completed by a predetermined time.
[0424] A power control method according to another aspect of the
present invention is a power control method for controlling
charging of a rechargeable battery of an electric vehicle, and
controlling supply of power to an electric device, the power
control method having: a charge information acquisition step of
acquiring charge information pertaining to the charging of the
rechargeable battery; a transmitting step of transmitting the
charge information acquired in the charge information acquisition
step, prior to the arrival of the electric vehicle at a location
where power is supplied to the electric vehicle; a receiving step
of receiving the charge information transmitted in the transmitting
step; and a power control step of determining a power supply start
time of supplying power to the electric device and a charging start
time of charging the rechargeable battery, on the basis of the
charge information received in the receiving step, such that the
supply of power to the electric device and the charging of the
rechargeable battery are completed by a predetermined time.
[0425] According to these configurations, the power control system
has an electric vehicle and a power control device that controls
charging of a rechargeable battery of the electric vehicle and
supply of power to an electric device. In the electric vehicle,
charge information pertaining to the charging of the rechargeable
battery is acquired, and the acquired charge information is
transmitted prior to the arrival of the electric vehicle at a
location where power is supplied to the electric vehicle. In the
power control device, the charge information transmitted by the
transmitter is received prior to the arrival of the electric
vehicle at the location where power is supplied to the electric
vehicle. On the basis of the received charge information, a power
supply start time of supplying power to the electric device and a
charging start time of charging the rechargeable battery are
determined such that the supply of power to the electric device and
the charging of the rechargeable battery are completed by a
predetermined time.
[0426] Because the power supply start time of supplying power to
the electric device and the charging start time of charging the
rechargeable battery are determined such that the supply of power
to the electric device and the charging of the rechargeable battery
are completed by the predetermined time prior to the arrival of the
electric vehicle at the location where power is supplied to the
electric vehicle, the supply of power to the electric device and
the charging of the electric vehicle can be performed
efficiently.
[0427] In the power control system described above, it is preferred
that the charge information include a current remaining level of
the rechargeable battery, and that the power control unit compute a
time frame required to charge the rechargeable battery, in
accordance with the current remaining level of the rechargeable
battery, and determine the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery, on the basis of the computed
time frame required to charge the rechargeable battery.
[0428] According to this configuration, the charge information
includes a current remaining level of the rechargeable battery. A
time frame required to charge the rechargeable battery is computed
in accordance with the remaining level of the rechargeable battery,
and the power supply start time of supplying power to the electric
device and the charging start time of charging the rechargeable
battery are determined based on the computed time frame required to
charge the rechargeable battery.
[0429] Therefore, the power supply start time of supplying power to
the electric device and the charging start time of charging the
rechargeable battery are determined based on the time frame
required to charge the rechargeable battery, the time frame being
computed in accordance with the current remaining level of the
rechargeable battery. Accordingly the power supply start time of
supplying power to the electric device can be brought forward or
backward in accordance with the length of the time frame required
to charge the rechargeable battery. As a result, the supply of
power to the electric device and the charging of the rechargeable
battery can be performed efficiently.
[0430] In the power control system described above, it is preferred
that the charge information include information on a remaining
level of the rechargeable battery that is obtained at the time of
vehicle arrival at an installation location where the power control
device is installed, the remaining level being obtained based on a
distance between a current position of the electric vehicle and the
installation location, and that the power control unit compute a
time frame required to charge the rechargeable battery, in
accordance with the remaining level of the rechargeable battery
that is obtained at the time of vehicle arrival at the installation
location, and determine the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery, on the basis of the computed
time frame required to charge the rechargeable battery.
[0431] According to this configuration, the charge information
includes information on a remaining level of the rechargeable
battery that is obtained at the time of arrival at an installation
location where the power control device is installed, the remaining
level being obtained based on a distance between a current position
of the electric vehicle and the installation location. Then, a time
frame required to charge the rechargeable battery is computed in
accordance with the remaining level of the rechargeable battery
that is obtained at the time of arrival at the installation
location, and the power supply start time of supplying power to the
electric device and the charging start time of charging the
rechargeable battery are determined on the basis of the computed
time frame required to charge the rechargeable battery.
[0432] Therefore, the power supply start time of supplying power to
the electric device and the charging start time of charging the
rechargeable battery are determined on the basis of the time frame
required to charge the rechargeable battery, the time frame being
computed in accordance with the remaining level of the rechargeable
battery that is obtained at the time of arrival at the installation
location. As a result, the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery can be determined more
accurately.
[0433] In the power control system described above, it is preferred
that the charge information include an estimated arrival time at
which the electric vehicle arrives at an installation location
where the power control device is installed, the estimated arrival
time being obtained based on a distance between a current position
of the electric vehicle and the installation location, and that the
power control unit determine the power supply start time of
supplying power to the electric device and the charging start time
of charging the rechargeable battery, such that the charging start
time of charging the rechargeable battery follows the estimated
arrival time and such that a total power of a power required to
charge the rechargeable battery and a power used for operating the
electric device does not exceed a predetermined value.
[0434] According to this configuration, the charge information
includes a estimated arrival time at which the electric vehicle
arrives at the installation location where the power control device
is installed, the estimated arrival time being obtained based on
the distance between the current position of the electric vehicle
and the installation location. Then, the power supply start time of
supplying power to the electric device and the charging start time
of charging the rechargeable battery are determined such that the
charging start time of charging the rechargeable battery follows
the estimated arrival time and such that a total power of a power
required to charge the rechargeable battery and a power used for
operating the electric device does not exceed a predetermined
value.
[0435] Therefore, the charging start time of charging the
rechargeable battery can be determined more accurately on the basis
of the estimated arrival time at which the electric vehicle arrives
at the installation location where the power control device is
installed. In addition, the operation of the electric device and
the charging of the rechargeable battery are controlled such that
the total power of the power required to charge the rechargeable
battery and the power used for operating the electric device does
not exceed the predetermined value.
[0436] In the power control system described above, it is preferred
that the charge information further include information on a
remaining level of the rechargeable battery that is obtained at the
time of vehicle arrival at an installation location where the power
control device is installed, the remaining level being obtained
based on a distance between a current position of the electric
vehicle and the installation location, and that the power control
unit compute a time frame required to charge the rechargeable
battery, in accordance with the remaining level of the rechargeable
battery that is obtained at the time of vehicle arrival at the
installation location, and determine the power supply start time of
supplying power to the electric device and the charging start time
of charging the rechargeable battery, on the basis of the computed
time frame required to charge the rechargeable battery and the
estimated arrival time.
[0437] According to this configuration, the charge information
further includes information on a remaining level of the
rechargeable battery that is obtained at the time of arrival at an
installation location where the power control device is installed,
the remaining level being obtained based on a distance between a
current position of the electric vehicle and the installation
location. Then, a time frame required to charge the rechargeable
battery is computed in accordance with the remaining level of the
rechargeable battery that is obtained at the time of arrival at the
installation location, and the power supply start time of supplying
power to the electric device and the charging start time of
charging the rechargeable battery are determined based on the
computed time frame required to charge the rechargeable battery and
the estimated arrival time.
[0438] Therefore, the power supply start time of supplying power to
the electric device and the charging start time of charging the
rechargeable battery are determined based on the estimated arrival
time and the time frame required to charge the rechargeable
battery, which is computed in accordance with the remaining level
of the rechargeable battery that is obtained at the time of arrival
at the installation location. As a result, the power supply start
time of supplying power to the electric device and the charging
start time of charging the rechargeable battery can be determined
more accurately.
[0439] In the power control system described above, it is preferred
that the power control system further have a server device that
mediates communication between the electric vehicle and the power
control device, and that the server device include: a distance
information receiver that receives, from the electric vehicle, the
distance between the current position of the electric vehicle and
the installation location where the power control device is
installed; a remaining level computing unit that computes the
remaining level of the rechargeable battery that is obtained at the
time of vehicle arrival at the installation location, on the basis
of the distance received by the distance information receiver; and
a remaining level transmitter that transmits the remaining level of
the rechargeable battery computed by the remaining level computing
unit, to the power control device.
[0440] According to this configuration, the power control system
further has a server device for mediating communication between the
electric vehicle and the power control device. In the server
device, the distance between the current position of the electric
vehicle and the installation location where the power control
device is installed is received from the electric vehicle, the
remaining level of the rechargeable battery that is obtained at the
time of arrival at the installation location is computed based on
the received distance, and the computed remaining level of the
rechargeable battery is transmitted to the power control
device.
[0441] Therefore, the remaining level of the rechargeable battery
obtained at the time of arrival at the installation location does
not have to be computed in the electric vehicle or the power
control device, reducing the number of processes performed in the
electric vehicle and the power control device.
[0442] In the power control system described above, it is preferred
that the power control device further have an electricity rate
information storage unit that stores electricity rate information
pertaining to an electricity rate that varies according to time
slots, and that the power control unit refer to the electricity
rate information stored in the electricity rate information storage
unit, and determine the power supply start time of supplying power
to the electric device and the charging start time of charging the
rechargeable battery, such that the charging of the rechargeable
battery is ended during a time slot in which the electricity rate
becomes equal to or lower than a predetermined rate.
[0443] According to this configuration, the electricity rate
information storage unit stores electricity rate information
pertaining to an electricity rate that varies according to time
slots. The electricity rate information stored in the electricity
rate information storage unit is referred to, and the power supply
start time of supplying power to the electric device and the
charging start time of charging the rechargeable battery are
determined such that the charging of the rechargeable battery is
ended during a time slot in which the electricity rate becomes
equal to or lower than a predetermined rate.
[0444] Because the charging of the rechargeable battery is ended
during the time slot in which the electricity rate becomes equal to
or lower than the predetermined rate, an electricity rate incurred
when charging the rechargeable battery can be reduced.
[0445] In the power control system described above, it is preferred
that the power control unit start charging the rechargeable battery
after the end of the supply of power to the electric device, and
supply power to the electric device only during the time slot in
which the electricity rate becomes equal to or lower than the
predetermined rate, in a case where the power supply start time of
supplying power to the electric device does not fall within the
time slot in which the electricity rate becomes equal to or lower
than the predetermined rate.
[0446] According to this configuration, the charging of the
rechargeable battery is started after the end of the supply of
power to the electric device. When the power supply start time of
supplying power to the electric device does not fall within the
time slot in which the electricity rate becomes equal to or lower
than the predetermined rate, power is supplied to the electric
device only during the time slot in which the time slot in which
the electricity rate becomes equal to or lower than the
predetermined rate. Therefore, an electricity rate incurred when
supplying power to the electric device can be reduced.
[0447] In the power control system described above, it is preferred
that the power control unit start charging the rechargeable battery
after the end of the supply of power to the electric device, and
start the supply of power to the electric device in a time slot
prior to the time slot in which the electricity rate becomes equal
to or lower than the predetermined rate, in a case where the power
supply start time of supplying power to the electric device does
not fall within the time slot in which the electricity rate becomes
equal to or lower than the predetermined rate.
[0448] According to this configuration, the charging of the
rechargeable battery is started after the end of the supply of
power to the electric device. When the power supply start time of
supplying power to the electric device does not fall within the
time slot in which the electricity rate becomes equal to or lower
than the predetermined rate, the supply of power to the electric
device is started in a time slot prior to the time in which the
electricity rate becomes equal to or lower than the predetermined
rate. Therefore, the operation of the electric device can be
controlled in consideration of convenience rather than reducing the
electricity rate.
[0449] In the power control system described above, it is preferred
that the power control unit compute an electricity rate incurred
when the operation of the electric device is started prior to the
charging start time, and an electricity rate incurred when the
operation of the electric device is started after charging ending
time, on the basis of the electricity rate information stored in
the electricity rate information storage unit, and then select the
lower electricity rate out of the computed electricity rates.
[0450] According to this configuration, an electricity rate
incurred when the operation of the electric device is started prior
to the charging start time and an electricity rate incurred when
the operation of the electric device is started after the charging
ending time, are computed based on the electricity rate information
stored in the electricity rate information storage unit. The lower
electricity rate is selected out of the computed electricity
rates.
[0451] Because the lower electricity rate is selected from the
electricity rate incurred when the operation of the electric device
is started prior to the charging start time and the electricity
rate incurred when the operation of the electric device is started
after the charging ending time, the electricity rate incurred when
supplying power to the electric device can be reduced.
[0452] In the power control system described above, it is preferred
that the electric device include an electric water heater that
boils water and stores the boiled water.
[0453] According to this configuration, operation of the electric
water heater that boils water and stores the boiled water can be
controlled appropriately.
[0454] A power control device according to another aspect of the
present invention is a power control device that controls charging
of a rechargeable battery of an electric vehicle and controls
supply of power to an electric device, the power control device
having: a receiver that receives charge information pertaining to
the charging of the rechargeable battery that is transmitted from
the electric vehicle, prior to the arrival of the electric vehicle
at a location where power is supplied to the electric vehicle; and
a power control unit that determines a power supply start time of
supplying power to the electric device and a charging start time of
charging the rechargeable battery, on the basis of the charge
information received by the receiver, such that the supply of power
to the electric device and the charging of the rechargeable battery
are completed by a predetermined time.
[0455] A power control program according to yet another aspect of
the present invention is a power control program that controls
charging of a rechargeable battery of an electric vehicle and
controls supply of power to an electric device, the power control
program causing a computer to function as: a receiver that receives
charge information pertaining to the charging of the rechargeable
battery that is transmitted from the electric vehicle, prior to the
arrival of the electric vehicle at a location where power is
supplied to the electric vehicle; and a power control unit that
determines a power supply start time of supplying power to the
electric device and a charging start time of charging the
rechargeable battery, on the basis of the charge information
received by the receiver, such that the supply of power to the
electric device and the charging of the rechargeable battery are
completed by a predetermined time.
[0456] According to these configurations, the charge information
pertaining to the charging of the rechargeable battery that is
transmitted from the electric vehicle is received prior to the
arrival of the electric vehicle at the location where power is
supplied to the electric vehicle. The power supply start time of
supplying power to the electric device and the charging start time
of charging the rechargeable battery are determined based on the
received charge information, such that the supply of power to the
electric device and the charging of the rechargeable battery are
completed by the predetermined time.
[0457] Because the power supply start time of supplying power to
the electric device and the charging start time of charging the
rechargeable battery are determined such that the supply of power
to the electric device and the charging of the rechargeable battery
are completed by the predetermined time prior to the arrival of the
electric vehicle at the location where power is supplied to the
electric vehicle, the supply of power to the electric device and
the charging of the electric vehicle can be performed
efficiently.
[0458] The specific embodiments or examples provided in the chapter
"Best Mode for Carrying Out the Invention" are merely to clarify
the technical contents of the present invention, and the present
invention should not be construed as being limited to such concrete
examples. Various modifications may be made within the spirit of
the present invention and the scope of the subjoined claims.
INDUSTRIAL APPLICABILITY
[0459] The power control system, the power control method, the
power control device and the power control program according to the
present invention are useful as a power control system, a power
control method, a power control device and a power control program,
which can efficiently supply power to an electric device, charge an
electric vehicle, control charging of a rechargeable battery of the
electric vehicle, and control supply of power to the electric
device.
* * * * *