U.S. patent application number 13/388741 was filed with the patent office on 2012-09-06 for air-conditioning system for a vehicle.
This patent application is currently assigned to Hitachi, Ltd.. Invention is credited to Yuto Imanishi, Tadashi Osaka, Itsuro Sawada, Sachio Sekiya.
Application Number | 20120222438 13/388741 |
Document ID | / |
Family ID | 44066180 |
Filed Date | 2012-09-06 |
United States Patent
Application |
20120222438 |
Kind Code |
A1 |
Osaka; Tadashi ; et
al. |
September 6, 2012 |
Air-Conditioning System for a Vehicle
Abstract
An air-conditioning system for a vehicle for performing
cooling/air-heating of a temperature controlling object includes: a
temperature detection unit 63 that detects a temperature of the
temperature controlling object; a controller 61 that controls the
air-conditioning system based on a temperature detected by the
temperature detection unit 63; a prediction unit 61 that predicts a
forward temperature of the temperature controlling object based on
at least either one of a detected temperature detected by the
temperature detection unit 63 and a current vehicle driving state;
a target temperature change unit 61 that changes a target
temperature of the temperature controlling object or a target
temperature of a cooling medium in the air-conditioning system for
a vehicle based on a result of prediction by the prediction unit
61; wherein the controller 61 controls cooling/air-heating of the
temperature controlling object based on a target temperature
changed by the target temperature change unit 61.
Inventors: |
Osaka; Tadashi;
(Kashiwa-shi, JP) ; Sekiya; Sachio;
(Hitachinaka-shi, JP) ; Sawada; Itsuro;
(Hitachinaka-shi, JP) ; Imanishi; Yuto;
(Hitachinaka-shi, JP) |
Assignee: |
Hitachi, Ltd.
Chiyoda-ku
JP
|
Family ID: |
44066180 |
Appl. No.: |
13/388741 |
Filed: |
August 25, 2010 |
PCT Filed: |
August 25, 2010 |
PCT NO: |
PCT/JP2010/064393 |
371 Date: |
March 15, 2012 |
Current U.S.
Class: |
62/126 |
Current CPC
Class: |
B60L 58/26 20190201;
Y02T 90/14 20130101; B60L 2200/36 20130101; Y02T 90/162 20130101;
B60L 2240/34 20130101; B60L 2240/36 20130101; Y02T 90/16 20130101;
B60L 2250/26 20130101; B60H 1/00271 20130101; B60H 1/00278
20130101; B60H 1/00735 20130101; B60H 1/00764 20130101; Y02T
10/7005 20130101; B60L 2240/545 20130101; B60L 2200/18 20130101;
B60L 2260/56 20130101; Y02T 10/7291 20130101; Y02T 10/705 20130101;
B60H 1/00807 20130101; B60H 2001/00307 20130101; B60L 53/14
20190201; B60L 2240/662 20130101; B60L 1/003 20130101; Y02T 10/70
20130101; Y02T 10/72 20130101; B60H 1/0073 20190501; B60L 2240/622
20130101; Y02T 10/7072 20130101; B60L 2240/642 20130101; B60L
2240/645 20130101; B60L 2240/525 20130101; B60L 2240/12 20130101;
B60L 2240/14 20130101; B60L 58/27 20190201 |
Class at
Publication: |
62/126 |
International
Class: |
F25B 49/02 20060101
F25B049/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2009 |
JP |
2009-272307 |
Claims
1. An air-conditioning system for a vehicle for performing
cooling/air-heating of a temperature controlling object,
comprising: a temperature detection unit that detects a temperature
of the temperature controlling object; a controller that controls
the air-conditioning system based on a temperature detected by the
temperature detection unit; a prediction unit that predicts a
forward temperature of the temperature controlling object based on
at least either one of a detected temperature detected by the
temperature detection unit and a current vehicle driving state; a
target temperature change unit that changes a target temperature of
the temperature controlling object or a target temperature of a
cooling medium in the air-conditioning system for a vehicle based
on a result of prediction by the prediction unit; wherein the
controller controls cooling/air-heating of the temperature
controlling object based on a target temperature changed by the
target temperature change unit.
2. An air-conditioning system for a vehicle according to claim 1,
further comprising: a refrigeration cycle circuit having a
compressor that compresses a first cooling medium and a first heat
exchanger that exchanges heat between the first cooling medium and
external air; a cooling circuit that circulates a second cooling
medium to the temperature controlling object to perform
cooling/air-heating of the temperature controlling object; and a
second heat exchanger that exchanges heat between the first cooling
medium and the second cooling medium, wherein the target
temperature change unit changes a target temperature of the
temperature controlling object or a target temperature of the
second cooling medium based on a result of prediction by the
prediction unit, and the controller controls the refrigeration
cycle circuit and the cooling circuit based on a temperature
detected by the temperature detection unit and a target temperature
changed by the target temperature change unit to control
cooling/air-heating of the temperature controlling object.
3. An air-conditioning system for a vehicle according to claim 2,
wherein the vehicle driving state includes a vehicle speed and an
accelerator pedal depressing amount input from vehicle side, and
the prediction unit predicts a forward temperature of the
temperature controlling object based on the vehicle speed, the
accelerator pedal depressing amount and a detected temperature
detected by the temperature detection unit.
4. An air-conditioning system for a vehicle according to claim 2,
wherein the prediction unit predicts a forward temperature taking
into consideration a travel plan information that is input from a
navigation unit provided to the vehicle.
5. An air-conditioning system for a vehicle, comprising: a
refrigeration cycle circuit having a compressor that compresses a
first cooling medium and a first heat exchanger that exchanges heat
between the first refrigerant and external air; a cooling circuit
that circulates a second cooling medium to a temperature
controlling object to perform cooling/air-heating of the
temperature controlling object; a second heat exchanger that
exchanges heat between the first cooling medium and the second
cooling medium; a temperature detection unit that detects a
temperature of the object of temperature adjustment; a controller
that controls the refrigeration cycle circuit and the cooling
circuit based on a temperature detected by the temperature
detection unit; a prediction unit that predicts a forward vehicle
travel state based on a travel plan information that is input from
a navigation device provided to the vehicle; and a target
temperature change unit that changes an target temperature of the
temperature controlling object or a target temperature of the
second cooling medium based on a result of prediction by the
prediction unit; wherein the controller controls the refrigeration
cycle circuit and the cooling circuit based on a target temperature
changed by the target temperature change unit to control
cooling/air-heating of the temperature controlling object.
6. An air-conditioning system for a vehicle according to claim 5,
wherein the temperature controlling object includes a vehicle
interior and an equipment for electric-powered driving, and the
controller performs cooling/air-heating of the vehicle interior and
the equipment for electric-powered driving based on the target
temperature, when the prediction unit predicts a vehicle state of
before start driving.
7. An air-conditioning system for a vehicle according to claim 5,
wherein the temperature controlling object includes a battery for
vehicle driving, and the controller controls cooling/air-heating
for the battery for vehicle driving by the cooling circuit so that
during charging a temperature of the battery for vehicle driving
falls within a predetermined temperature range in which the battery
for vehicle driving exhibits optimal charging/discharging
efficiency, when the prediction unit predicts a charging of the
battery for vehicle driving.
8. An air-conditioning system for a vehicle according to claim 7,
wherein during the charging, the refrigeration cycle circuit and
the cooling circuit are driven by power of an external power source
that is used in charging the battery for vehicle driving.
9. An air-conditioning system for a vehicle according to claim 2,
wherein the temperature controlling object includes a vehicle
interior and an equipment for electric-powered driving, and the
controller performs controlling of cooling/air-heating of the
equipment for electric-powered driving with higher priority over
controlling of cooling/air-heating of the vehicle interior, when a
temperature of the equipment for electric-powered driving is in the
vicinity of the target temperature.
Description
TECHNICAL FIELD
[0001] The present invention relates to an air-conditioning system
for a vehicle.
BACKGROUND ART
[0002] In the field of hybrid vehicles, there are known systems for
use in air-conditioning in which heat generated by an
heat-generating body such as a motor or an inverter installed in a
vehicle is used for air-conditioning (see Patent Literatures 1 and
2). According to the invention disclosed in the Patent Literature
1, it is possible to implement cooling of equipment and air-cooling
simultaneously by using a refrigeration cycle.
[0003] According to the invention disclosed in the Patent
Literature 2, there is provided a technology for heating the
blowing air of air-conditioning with both the heat generated by a
heat pump type air-cooling apparatus and the heat generated by a
heater during air-heating.
CITATION LIST
Patent Literature
[0004] [Patent Literature 1] Japanese Patent No. 4285292. [0005]
[Patent Literature 2] Japanese Patent Application Laid-open
Publication No. 2008-230594
SUMMARY OF INVENTION
Technical Problem
[0006] In case that cooling or warming of each of equipment (motor,
inverter, battery and so on) mounted on a vehicle and air-cooling
and air-heating of the vehicle interior are performed by a single
air-conditioning system, it is necessary to bring the equipment and
the vehicle interior to a target temperatures effectively.
Solution to Problem
[0007] According to the 1st aspect of the present invention, an
air-conditioning system for a vehicle for performing
cooling/air-heating of a temperature controlling object, comprises:
a temperature detection unit that detects a temperature of the
temperature controlling object; a controller that controls the
air-conditioning system based on a temperature detected by the
temperature detection unit; a prediction unit that predicts a
forward temperature of the temperature controlling object based on
at least either one of a detected temperature detected by the
temperature detection unit and a current vehicle driving state; a
target temperature change unit that changes a target temperature of
the temperature controlling object or a target temperature of a
cooling medium in the air-conditioning system for a vehicle based
on a result of prediction by the prediction unit; wherein the
controller controls cooling/air-heating of the temperature
controlling object based on a target temperature changed by the
target temperature change unit.
[0008] According to the 2nd aspect of the present invention, an
air-conditioning system for a vehicle according to the 1st aspect
further comprises: a refrigeration cycle circuit having a
compressor that compresses a first cooling medium and a first heat
exchanger that exchanges heat between the first cooling medium and
external air; a cooling circuit that circulates a second cooling
medium to the temperature controlling object to perform
cooling/air-heating of the temperature controlling object; and a
second heat exchanger that exchanges heat between the first cooling
medium and the second cooling medium, wherein the target
temperature change unit changes a target temperature of the
temperature controlling object or a target temperature of the
second cooling medium based on a result of prediction by the
prediction unit, and the controller controls the refrigeration
cycle circuit and the cooling circuit based on a temperature
detected by the temperature detection unit and a target temperature
changed by the target temperature change unit to control
cooling/air-heating of the temperature controlling object.
[0009] According to the 3rd aspect of the present invention, in an
air-conditioning system for a vehicle according to the 2nd aspect,
it is preferred that the vehicle driving state includes a vehicle
speed and an accelerator pedal depressing amount input from vehicle
side, and the prediction unit predicts a forward temperature of the
temperature controlling object based on the vehicle speed, the
accelerator pedal depressing amount and a detected temperature
detected by the temperature detection unit.
[0010] According to the 4th aspect of the present invention, in an
air-conditioning system for a vehicle according to the 2nd aspect,
it is preferred that the prediction unit predicts a forward
temperature taking into consideration a travel plan information
that is input from a navigation unit provided to the vehicle.
[0011] According to the 5th aspect of the present invention, an
air-conditioning system for a vehicle comprises: a refrigeration
cycle circuit having a compressor that compresses a first cooling
medium and a first heat exchanger that exchanges heat between the
first cooling medium and external air; a cooling circuit that
circulates a second cooling medium to a temperature controlling
object to perform cooling/air-heating of the temperature
controlling object; a second heat exchanger that exchanges heat
between the first cooling medium and the second cooling medium; a
temperature detection unit that detects a temperature of the object
of temperature adjustment; a controller that controls the
refrigeration cycle circuit and the cooling circuit based on a
temperature detected by the temperature detection unit; a
prediction unit that predicts a forward vehicle travel state based
on a travel plan information that is input from a navigation device
provided to the vehicle; and a target temperature change unit that
changes an target temperature of the temperature controlling object
or a target temperature of the second cooling medium based on a
result of prediction by the prediction unit; wherein the controller
controls the refrigeration cycle circuit and the cooling circuit
based on a target temperature changed by the target temperature
change unit to control cooling/air-heating of the temperature
controlling object.
[0012] According to the 6th aspect of the present invention, in an
air-conditioning system for a vehicle according to the 5th aspect,
it is preferred that the temperature controlling object includes a
vehicle interior and an equipment for electric-powered driving, and
the controller performs cooling/air-heating of the vehicle interior
and the equipment for electric-powered driving based on the target
temperature, when the prediction unit predicts a vehicle state of
before start driving.
[0013] According to the 7th aspect of the present invention, in an
air-conditioning system for a vehicle according to the 5th aspect,
it is preferred that the temperature controlling object includes a
battery for vehicle driving, and the controller controls
cooling/air-heating for the battery for vehicle driving by the
cooling circuit so that during charging a temperature of the
battery for vehicle driving falls within a predetermined
temperature range in which the battery for vehicle driving exhibits
optimal charging/discharging efficiency, when the prediction unit
predicts a charging of the battery for vehicle driving.
[0014] According to the 8th aspect of the present invention, in an
air-conditioning system for a vehicle according to the 7th aspect,
it is preferred that during the charging, the refrigeration cycle
circuit and the cooling circuit are driven by power of an external
power source that is used in charging the battery for vehicle
driving.
[0015] According to the 9th aspect of the present invention, in an
air-conditioning system for a vehicle according to the 2nd or 5th
aspect, it is preferred that the temperature controlling object
includes a vehicle interior and an equipment for electric-powered
driving, and the controller performs controlling of
cooling/air-heating of the equipment for electric-powered driving
with higher priority over controlling of cooling/air-heating of the
vehicle interior, when a temperature of the equipment for
electric-powered driving is in the vicinity of the target
temperature.
Advantageous Effect of the Invention
[0016] According to the present invention, it is possible to
perform cooling/air-heating of an object of temperature control
efficiently.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows a schematic block diagram of the structure of
an air-conditioning system for a vehicle according to the present
invention;
[0018] FIG. 2 is a diagram illustrating an air-cooling
operation;
[0019] FIG. 3 is a diagram illustrating a dehumidifying
operation;
[0020] FIG. 4 is a diagram illustrating an air-heating
operation;
[0021] FIG. 5 is a diagram illustrating an
air-heating/equipment-cooling operation;
[0022] FIG. 6 is a diagram illustrating a equipment-heating
operation;
[0023] FIG. 7 is a diagram showing a cooling construction of a
gearbox, with (a) showing a first example thereof and (b) showing a
second example thereof;
[0024] FIG. 8 is a diagram showing temperature conditions for every
object of temperature controlling:
[0025] FIG. 9 is a diagram illustrating arrangement of a plurality
of pieces of temperature controlling object equipment 9, showing a
case of serial arrangement;
[0026] FIG. 10 is a diagram illustrating an arrangement of a
plurality of object equipments 9 for temperature control, where the
equipments are in parallel arrangement;
[0027] FIG. 11 is a flowchart showing a program for control
processing;
[0028] FIG. 12 is a diagram showing relationship between the
external air temperature and the air-conditioning of vehicle
interior and each equipment;
[0029] FIG. 13 is a diagram illustrating an example of prediction
of temperature variation, with (a) showing a change of accelerator
pedal depressing amount, (b) showing a variation of temperature of
a motor or an inverter, and (c) showing a variation of temperature
of an equipment cooling medium 41B.
[0030] FIG. 14 illustrates an example of processing in which
cooling performance for the equipments will be increased,
indicating a case in which compressor 1, circulation pump 5B, and
exterior fan 3 can be variably controlled;
[0031] FIG. 15 shows an example of processing in which cooling
performance for the equipments is increased, indicating a case in
which the compressor 1, the circulation pump 5B, and the exterior
fan 3 are on-off controlled;
[0032] FIG. 16 is a diagram showing an example of control in which
cooling performance for the equipments is decreased, with (a)
indicating a case that the compressor 1, the circulation pump 5B,
and the exterior fan 3 can be variably controlled, and (b)
indicating a case that the compressor 1, the circulation pump 5B,
and the exterior fan 3 are on-off controlled;
[0033] FIG. 17 is a diagram illustrating examples how the
controlling temperatures are set for various vehicle states and for
temperature controlling objects (vehicle interior, equipments);
[0034] FIG. 18 is a diagram illustrating an example of cooling and
heating control when battery is charged; and
[0035] FIG. 19 is a diagram showing a construction of EV1000
driving system and electrical connection of components in a portion
of the driving system that comprises an electric-motor driving
system that.
DESCRIPTION OF EMBODIMENTS
[0036] Hereafter, embodiments of the present invention are
explained. In the following embodiments, the present invention is
explained with an example where it is assumed that the present
invention is applied to an air-conditioning system of a pure
electric vehicle that employs an electric motor as a sole drive
power source for the vehicle.
[0037] The configuration of the embodiment explained below may be
applied as a vehicular air-conditioning systems for electric
vehicles that employs as drive power sources both an engine that is
an internal combustion engine and an electric motor, for example,
hybrid vehicles (passenger cars), hybrid trucks, hybrid buses and
so on.
[0038] First, referring to FIG. 19, explanation is made on an
electric-motor driving system for a pure electric vehicle
(hereafter, simply referred to as "EV") to which the vehicular
air-conditioning system according to the present invention is
applied. FIG. 19 shows a configuration of the drive system EV1000
and electrical connection of each component in an electric-motor
drive system that constitutes a part thereof. Note that in FIG. 19,
thick solid lines indicate high voltage lines and thin solid lines
indicate low voltage lines.
[0039] An axle 820 is rotatably supported in the front portion or
rear portion of the vehicle body (not shown). On both ends of the
axle 820 are provided a pair of driving wheels 800. Though not
shown, at the rear portion or the front portion of the vehicle body
is rotatably supported an axle provided with a pair of non-driving
wheels on both ends thereof. EV1000 shown in FIG. 19 is of a
front-wheel drive type having the driving wheels 800 as front
wheels and the non-driving wheels as rear wheels. However, a
rear-wheel drive type having drive wheels 800 as rear wheels and
the driving wheels as front wheels may also be used.
[0040] In the midportion of the axle 820 is provided a differential
gear (hereafter, referred to as "DIF") 830. The axle 820 is
mechanically connected to the output side of the DIF 830. To the
input side of DIF 830 is mechanically connected an output shaft of
a transmission 810. DIF 830 is a differential power distribution
mechanism that distributes rotative drive force transmitted via the
transmission 810 with speed change to the left and right vehicle
axles 820. To the input side of the transmission 810 is
mechanically connected the output side of a motor generator
200.
[0041] The motor generator 200 is a rotating electrical machine
that includes an armature (corresponding to the stator in EV 1000
shown in FIG. 3) 210 provided with armature winding 211 and a field
system 220 provided with a permanent magnet 221 (corresponding to
the rotor in EV 1000 shown in FIG. 3) and arranged opposite to the
armature 210 via a gap. The motor generator 200 functions as a
motor when EV 1000 is on power driving and as a generator when it
is regenerating.
[0042] When the motor generator 200 functions as a motor, electric
energy accumulated in a battery 100 is supplied to the winding of
the armature 211 through an inverter 300. As a result, the motor
generator 200 generates rotative power (mechanical energy) due to
magnetic interaction between the armature 210 and the field system
220. The rotative power output from the motor generator 200 is
transmitted to the axle 820 via the transmission 810 and DIF 830 to
drive the driving wheels 800.
[0043] When the motor generator 200 functions as a generator, the
mechanical energy (rotative power) transmitted from the driving
wheels 800 is transmitted to the motor generator 200 to drive the
motor generator 200. In this manner, when the motor generator 200
is driven, the magnetic fluxes of the field system 220 interlink
with the winding 211 of the armature to induce voltage. Due to
this, the motor generator generates power. The power output from
the motor generator 200 is supplied to the battery 100 through the
inverter 300. As a result, the battery 100 is charged.
[0044] The motor generator 200, particularly the temperature of the
armature 210 is controlled by the heat cycling system explained
later such that the temperature falls within an allowable
temperature range. The armature is a heat generating component, so
that it is necessary to cool it. When ambient temperature is
relatively low, it may sometimes be necessary to warm it in order
to obtain specified electric properties.
[0045] The motor generator 200 is driven by controlling electric
power by the inverter 300 between the armature 210 and the battery
100. That is, the inverter 300 is a control device for the motor
generator 200. The inverter 300 is a power converting device that
converts the power from direct current to alternating current or
from alternating current to direct current by switching actions of
a switching semiconductor element. The inverter 300 includes a
power module 310, a drive circuit 330, an electrolytic capacitor
320, and a motor controller 340. The drive circuit 330 drives a
switching semiconductor devices implemented in the power module
310. The electrolytic capacitor 320 is electrically connected with
the direct current side of the power module 310 in parallel to
smooth the direct current voltage. The motor controller 340
generates a switching command for switching semiconductor devices
of the power module 310, and outputs a signal corresponding to the
switch command to the drive circuit 330.
[0046] The power module 310 includes three series circuits (each
series circuit is an arm for one phase) for three phases, wherein
each of series circuit (arm for one phase) comprises two switching
semiconductor devices (one for an upper arm and the other for lower
arm) electrically connected in series. The power module 310
comprises six switching semiconductor devices which are implemented
on a substrate and are electrically connected with a connection
conductor such as an aluminum wire, so that three series circuits
corresponding to three phases are electrically connected in
parallel (three-phase bridge connection) to constitute a power
conversion circuit.
[0047] As the switching semiconductor device, use is made of a
metal oxide film semiconductor field effect transistor (MOSFET) or
an insulated gate type bipolar transistor (IGBT). Here, in case
where the power conversion circuit is constituted by MOSFET, a
parasitic diode is present between a drain electrode and a source
electrode, so that it is unnecessary to separately provide a diode
device therebetween. On the other hand, in case where the power
conversion circuit is constituted by IGBT, no diode element exists
between a collector electrode and an emitter electrode, so that it
is necessary to electrically connect a diode device with reversed
direction in parallel between the collector electrode and the
emitter electrode.
[0048] One side of each upper arm, which is the side opposite to a
side that is connected to a lower arm, i.e. collector electrode
side in the case of IGBT, is extending to outside from a direct
current side of the power module 310 and is connected to a positive
electrode side of the battery 100. The other side of each lower
arm, which is the side opposite to a side that is connected to an
upper arm (emitter electrode side in the case of IGBT) to outside
from a direct current side of the power module 310 and is connected
to a negative electrode side of the battery 100. A midpoint of each
pair of upper and lower arms, i.e., a connection point, at which a
side of the upper arm connected with the lower arm (emitter
electrode side of the upper arm in the case of IGBT) and a side of
the lower arm connected with the upper arm are joined, is extending
to outside from an alternate current side of the power module 310
and electrically connected to a wiring of the armature 211 of a
corresponding phase.
[0049] The electrolytic capacitor 320 is provided in order to
suppress voltage fluctuation that is caused by high speed switching
of the switching semiconductor devices and parasite inductance in
the power conversion circuit. The electrolytic capacitor 320
functions as a smoothing capacitor that removes an alternate
current component contained in a direct current component. The
smoothing capacitor may be a film capacitor.
[0050] The motor controller 340 is an electronic circuit device
that generates switch command signals (for example, PWM (pulse
width modulation) signals) for six switching semiconductor devices
corresponding to a torque command signal output from a vehicle
controller 840 that controls the vehicle in whole and outputs the
generated switch command signals to the drive circuit 330.
[0051] The drive circuit 330 is an electronic circuit device that
generates drive signals for six semiconductor devices corresponding
to a switch command signal output from the motor controller 340 and
outputs the generated drive signals to gate electrodes of the six
switching semiconductor devices.
[0052] In the inverter 300, in particular in the power module 310
and in the electrolytic capacitor 320 are, their temperatures are
controlled by the heat cycling system described later so that the
temperatures fall within an allowable temperature range. Since the
power module 310 and the electrolytic capacitor 320 are heat
generating components, so that it is necessary to cool them. In
case when the ambient temperature is relatively low, it may be
necessary to warm them in order to obtain specified functioning-
and electrical properties.
[0053] The vehicle controller generates a motor torque command
signal for the motor controller 340 based on a plurality of state
parameters that indicates the vehicle operational state and outputs
the generated motor torque command signal to the motor controller
340. Examples of the plurality of state parameters that indicates
the vehicle operational state include a torque demand (depressing
amount of the accelerator pedal or a throttle position), vehicle
speed, and so on.
[0054] The battery 100 is a battery that generates a high voltage
of 200 volts or higher as nominal output voltage, which constitutes
a drive power source for the motor generator 200. The battery 100
is electrically connected with the inverter 300 and a charger 500
through a junction box 400. A lithium ion battery is used as the
battery 100.
[0055] Other electrical storage devices such as a lead battery as
the battery 100, a nickel hydride battery, an electrical double
layer capacitor, a hybrid capacitor may be used as the battery
100.
[0056] The battery 100 is an electrical storage device that is
charged and discharged by the inverter 300 and the charger 500. It
includes the battery unit 110 and a control unit as major
parts.
[0057] The battery 110 functions as a storage device of electrical
energy and is constituted by a plurality of lithium ion battery
cells that can store and discharge electrical energy (charging and
discharging of direct current power) electrically connected in
series. The battery unit 110 is electrically connected with the
inverter 300 and the charger 500.
[0058] The control unit is an electronic control device constituted
by a plurality of electronic circuit components. It manages and
controls the state of the battery unit 110 and provides information
about allowable charging/discharging amount to the inverter 300 and
the charger 500 to control input and output of electrical energy in
and from the battery unit 110.
[0059] The electronic control device is constituted by two
hierarchical levels from the viewpoint of function. It includes the
battery control unit 130 that corresponds to a higher level
(parent) in the battery 100 and the cell control unit 120 that
corresponds to a lower level (child) with respect to the battery
control unit 130.
[0060] The cell control unit 120 operates as a subordinate to the
batter control unit 130 based on a command signal output from the
battery control unit 130. It includes a plurality of battery cell
management means that manages and controls respective states of the
plurality of the lithium ion battery cells. The plurality of
battery cell management means is constituted by integrated circuits
(ICs), respectively. In case where the battery unit 110 has a
structure such that a plurality of lithium ion battery cells
electrically connected in series is divided into a plurality of
groups, the plurality of integrated circuits is provided
corresponding to the plurality of groups, respectively. Each
integrated circuit detects respective voltages and
overcharge-overdischarge abnormalities of the plurality of lithium
ion battery cells contained in the corresponding group.
[0061] The battery control unit 130 is an electronic control device
that manages and controls the state of the battery unit 110 and
notifies an allowable charge- and discharge amount to the vehicle
controller 840 or the motor controller 340 to control input and
output of electric energy in and from the battery unit 110; the
battery control unit 130 is provided with a state detection means.
The state detection means is a calculation processor such as a
microcomputer or a digital signal processor.
[0062] A plurality of signals is input to the state detection means
of the battery control unit 130. The plurality of signals includes
a measurement signal output for a current measurement means for
measuring charge-discharge current of the battery unit 110, a
measurement signal output from a voltage measurement means for
measuring charge-discharge voltage of the battery unit 110, a
measurement signal output from a temperature measurement means for
measuring temperatures of the battery unit 110 and of some of the
lithium ion battery cells, respectively, a detection signal
relating to terminal voltage of the plurality of lithium ion
battery cells output from the cell control unit 120, an abnormality
signal output from the cell control unit 120, an on-off signal
based on an action of an ignition key switch, and a signal output
from the vehicle controller 840 or the motor controller 340, which
is a control device of a higher hierarchical level than the battery
control unit 130.
[0063] The state detection means of the battery control unit 130
performs a plurality of calculations based on a plurality of
informations. The plurality of informations includes information
obtained from the above-mentioned input information,
characteristics information of the lithium ion battery cell and
calculation information necessary for calculations. The plurality
of calculations includes calculations to obtain SOC (state of
charge) and SOH (state of health) of the battery unit 110,
calculations for balancing states of charge among the plurality of
lithium ion battery cells, and calculations for controlling the
charge- and discharge amount of the battery unit 110. The state
detection means of the battery control unit 130, based on results
of these calculations, generates and outputs a plurality of signals
including a command signal to the cell control unit 120, a signal
relating to allowable charge- and discharge amount for controlling
the charge-discharge amount of the battery unit 110, a signal
relating to SOC of the battery unit 110, and a signal relating to
SOH of the battery unit 110.
[0064] The state detection means of the battery control unit 130
generates and outputs a plurality of signals including a command
signal to open the first positive- and negative relays 410, 420,
and a signal for notifying abnormal state based on the abnormality
signal output from the cell control unit 120.
[0065] The battery control unit 130 and the cell control unit 120
are constructed so as to communicate signals therebetween through a
signal transmission path but are electrically insulated from each
other. This is because they have different operation power sources
and different base potentials from each other. To this end, an
insulator 140 such as a photocoupler, a capacitive coupling
element, or a transformer is provided on the signal transmission
path between the battery control unit 130 and the cell control unit
120. As a result, the battery control unit 130 and the cell control
unit 120 can transmit signals having different base potentials to
each other.
[0066] In the battery 100, in particular in the battery unit 110,
its temperature is controlled so that the temperature falls within
the allowable temperature range by the heat cycling system
described later. The battery unit 110 is an heat-generating
component, and therefore it needs to be cooled, and in case when
the ambient temperature is relatively low, it may sometimes be
necessary to be warmed up in order to obtain specified input- and
output characteristics.
[0067] The electric energy stored in the battery 100 is used as a
drive power of the electric-motor driving system that drives
EV1000. Accumulation of electric energy in the battery 100 is
achieved by exploiting a regenerated power generated by a
regeneration operation of the electric-motor driving system, a
power taken from a commercial power source for domestic use, or a
power purchased from a charging station.
[0068] In case the battery 100 is to be charged from a commercial
power source 600 for domestic use, a power source plug 550 at the
end of a power cable, which is electrically connected with an
external power source connection terminal of the charger 500, is
inserted into an electric outlet 700 on the commercial power source
600 side to electrically connect the charger 500 and the commercial
power source 600 with each other. Alternatively, in case where the
battery 100 is to be charged from a power feeder in the charging
station, the power cable extending from the power feeder of the
charging station is connected with an external power source
connection terminal of the charger 500 to electrically connect the
charger 500 and the power feeder of the charging station with each
other. As a result, alternate current power is supplied from the
commercial power source 600 or from the power feeder of the
charging station to the charger 500. The charger 500 converts the
supplied alternate current power into direct current power and
adjusts the voltage to a charging voltage of the battery 100 before
supplying the power to the battery 100. As a result, the battery
100 is charged.
[0069] Charging of the battery 100 from the power feeder of the
charging station can be performed basically in the same manner as
the charging of the battery 100 from the commercial power source
600 at home. However, the current amount supplied to the charger
500 and charging time are different for charging from the
commercial power source 600 at home and for charging from the power
feeder of the charging station. The charging with the power feeder
of the charging station can charge a larger current amount in a
shorter charging time than the charging with the commercial power
source 600 at home. That is, the charging with the power feeder of
the charging station enables rapid charging.
[0070] The charger 500 is a power conversion unit that converts the
alternate current power supplied from the commercial power source
600 at home or the alternate current power supplied from the power
feeder of the charging station into direct current power, and
further boosts the converted direct current power to a charging
voltage for supplying it to the battery 100. The charger 500
includes as main components an alternate current-direct current
conversion circuit 510, a booster circuit 520, a driver circuit
530, and a charging control unit 540.
[0071] The alternate current-direct current conversion circuit 510
is a power conversion circuit that converts the alternate current
power supplied from an external power source to direct current
power and outputs the converted direct current power, and comprises
a rectifier circuit and a power factor improvement circuit. The
rectifier circuit is constituted by, for example, a plurality of
diode devices in bridge connection structure and rectifies
alternate current power supplied from an external power source into
direct current power. The power factor improvement circuit is
electrically connected to the direct current side of the rectifier
circuit and improves the power factor of the rectifier circuit
output. As the circuit that converts alternate current power into
direct current power, a circuit may be constructed by
bridge-connecting a plurality of switching semiconductor devices,
to each of which is parallel connected with a diode element in
reverse direction.
[0072] The booster circuit 520 is a power conversion circuit that
boosts the direct current power output from the alternate
current-direct current circuit 510 (power factor improvement
circuit) up to the charging voltage of the battery 100 and is
constituted by, for example, DC-DC converter of an insulated type.
The DC-DC converter of an insulated type is constituted by a
transformer, a conversion circuit, a rectifier circuit, a smoothing
reactor, and a smoothing capacitor. The conversion circuit includes
a plurality of switching semiconductor devices that are connected
in bridge connection and are electrically connected to the primary
wiring side of the transformer, converting the direct current power
output from the alternate current-direct current conversion circuit
510 into alternate current power and inputs the converted alternate
current power into the primary wiring side of the transformer. The
rectifier circuit is constituted by a plurality of diode elements
connected in bridge connection. It is electrically connected to the
secondary wiring side of the transformer and rectifies the
alternate current power generated at the secondary wiring side of
the transformer into direct current power. The smoothing reactor is
electrically connected in series to the positive electrode side on
the output side (direct current side) of the rectifier circuit. The
smoothing capacitor is electrically connected with between the
positive and negative electrodes on the output side (direct current
side) of the rectifier circuit.
[0073] The charging control unit 540 is an electronic circuit unit
constructed by implementing a plurality of electronic components
including an arithmetic processing unit such as a microcomputer
packed on a circuit board. The charging control unit 540 starts and
stops charging of the battery 100 by the charger 500 and controls
power, voltage, current and so on supplied from the charger 500 to
the battery 100 upon the charging. To perform such controls, the
charging control unit 540 generates switch command signals (for
example, PWM (pulse width-modulated modulation) signals) for a
plurality of switching semiconductor devices of the boost circuit
520 in response to the signal output for the vehicle controller 840
and the signal output from the controller of the battery 100 and
outputs the generated signals to the driver circuit 530.
[0074] The vehicle controller 840 monitors, for example, the
voltage of the input side of the charger 500, and outputs a command
signal to start up charging to the charging control unit 540 when
it is determined that the charger 500 is in a condition to start up
charging wherein the charger 500 is electrically connected with the
external power source so that voltage is applied to the input side
of the charger 500. On the other hand, when it is determined that
the battery 100 is in a full charged state based on the battery
state signal output from the controller of the battery 100, the
vehicle controller 840 outputs a command signal to stop the
charging to the charging control unit 540. Such an operation may be
performed by the motor controller 340, by the controller of the
battery 100 or by the charging control unit 540 itself in
cooperation with the controller of the battery 100.
[0075] The controller of the battery 100 detects the state of the
battery 100 and calculates an allowable charge amount of the
battery 100 and outputs a signal relating to the result of the
calculation to the charger 500 in order to control the charging of
the battery 100 by the charger 500.
[0076] The driver circuit 530 is an electronic circuit unit that is
constructed by implementing a plurality of electronic components
such as switching semiconductor devices or amplifiers on a circuit
board. The driver circuit 530 generates drive signals for a
plurality of switching semiconductor devices of the booster circuit
520 in response to the command signal output from the charging
control unit 540, and outputs the generated drive signals to the
gate electrodes of the plurality of the switching semiconductor
devices.
[0077] In a case that the alternate current-direct current
conversion circuit 510 is constructed by switching semiconductor
devices, a switch command signal for a switching semiconductor
device of the alternate current-direct current conversion circuit
510 is output to the driver circuit 530. The driver circuit 530
outputs a drive signal for the switching semiconductor device of
the alternate current-direct current conversion circuit 510 to the
gate electrode thereof to control switching of the switching
semiconductor device of the alternate current-direct current
conversion circuit 510.
[0078] The first and second positive electrode side relays 410, 430
and the first and second negative electrode side relays 420, 440
are accommodated inside the junction box 410.
[0079] The first positive electrode side relay 410 is a switch to
control electrical connection between the direct current positive
electrode side of the inverter 300 (power module 310) and the
positive electrode side of the battery 100. The first negative
electrode side relay 420 is a switch to control electrical
connection between the direct current negative electrode side of
the inverter 300 (power module 310) and the negative electrode side
of the battery 100. The second positive electrode side relay 430 is
a switch to control electrical connection between the direct
current positive electrode side of the charger 500 (booster circuit
520) and the positive electrode side of the battery 100. The second
negative side relay 440 is a switch to control electrical
connection between the direct current negative electrode side of
the charger 500 (booster circuit 500) and the negative electrode
side of the battery 100.
[0080] The first positive electrode side relay 410 and the first
negative electrode side relay 420 are closed when the system is in
an operation mode where the rotative power of the motor generator
200 is required and in an operation mode where electric power
generation is required. They are opened when abnormality occurs in
the electric-motor driving system or in the vehicle and when the
battery 100 is charged by the charger 500. On the other hand, the
second positive electrode side relay 430 and the second negative
electrode side relay 440 are closed when the battery 100 is charged
by the charger 500. They are opened when the charging of the
battery 100 is completed and when abnormality occurs in the charger
500 or in the battery 100.
[0081] Open/close of the first positive electrode side relay 410
and the first negative electrode side relay 420 is controlled by an
open/close command signal output from the vehicle controller 840.
The open/close of the first positive electrode side relay 410 and
the first negative electrode side relay 420 may be controlled by an
open/close command signal output from other controller, for
example, the motor controller 340 or the controller of the battery
100. The open/close of the second positive electrode relay 430 and
the second negative electrode side relay 440 is controlled by an
open/close command signal output from the charging control unit
540. The open/close of the second positive electrode side relay 430
and the second negative electrode side relay 440 may be controlled
by an open/close command signal output from other control unit, for
example, the vehicle control unit 840 or the control unit of the
battery 100.
[0082] As mentioned above, in EV1000, the first positive electrode
side relay 410, the first negative electrode side relay 420, the
second positive electrode side relay 430, and the second negative
electrode side relay 440 are provided between the battery 100 and
the inverter 300 and between the battery 100 and the charger 500.
As a result, high safety of the electric-motor driving system that
is at a high voltage can be secured.
[0083] Now, a heat cycling system installed in EV 1000 is
explained. EV 1000 includes, as heat cycling systems, an
air-conditioning system that controls the condition of air in the
vehicle interior and a temperature control system that controls the
temperature of an heat-generating body such as the battery 100, the
motor generator 200, and the inverter 300.
[0084] An energy source is required for operating the
air-conditioning system and the temperature control system. To this
end, EV 1000 uses the battery 100 in the motor generator 200 as
such an energy source. Note that the air-conditioning system and
the temperature adjustment system consume more electrical energy
from the battery 100 than other electrical loads do.
[0085] EV 1000 attracts high attention to the fact that it gives
less (more particularly null) influence on the global environment
than hybrid vehicles (hereafter, referred to as "HEV").
[0086] However, EV 1000 is less accepted in the market than HEV,
since EV1000 shows a low mileage per one charging of the battery
100, and moreover since promoting of infrastructure such as
charging stations is still on the way. Further, EV 1000 consumes
much more electrical energy for a desired travel distance than is
required by a HEV, so that the battery 100 should have a larger
capacity than that of a HEV. As a result, the cost of the battery
100 is higher for EV 1000 than for HEV, resulting in a higher cost
of the vehicle than HEY. Therefore, EV 1000 is less accepted in the
market than HEY.
[0087] In order for EV 1000 to be more accepted in the market, it
is necessary to increase the mileage per one charging of the
battery 100 of EV. To increase the mileage per one charging of the
battery 100 of EV, it is necessary to suppress consumption of
electrical energy stored in the battery 100 other than driving of
the motor generator 200.
[0088] The heat-generating bodies such as the battery 100, the
temperatures of motor generator 200 and inverter 300 are controlled
so that these temperatures fall within allowable temperature
ranges. The heat-generating bodies abruptly change their outputs
corresponding to variation in load of EV 1000, and accordingly the
amount of generated heat is varied. To operate an heat-generating
body at high efficiency, it is desirable to vary the performance of
the temperature control system according to variation of heat
generation (temperature) of the heat-generating body so that the
temperature of the heat-generating body will be maintained always
at an optimum temperature.
[0089] On the other hand, in order for EV 1000 to be more accepted
in the market, it is necessary to reduce cost of heat-generating
bodies such as battery 100, motor generator 200, and inverter 300
to lower the price of the vehicle comparable to that of a HEV. To
reduce the cost of the heat-generating body, it is necessary to
reduce the size of and increase the output of the heat-generating
body. However, if the heat-generating body has a reduced size and
an increased output, the amount of heat generation (temperature)
increases, so that it is necessary to increase the performance of
the temperature control system for the heat-generating body.
[0090] In the embodiment described below, within a heat cycling
system of EV1000, a temperature control system and an
air-conditioning system are integrally constructed, in order for
heat energy to be efficiently used for interior air-conditioning
and for temperature control of the heat-generating body.
[0091] Specifically, the heat cycling is divided into a primary
heat cycling that exchanges heat with exterior and a secondary heat
cycling that exchanges heat with interior and the heat-generating
body. The primary heat cycling is constituted by a refrigeration
cycle system and the secondary heat cycle circuit is constituted by
two heat transfer systems, each of which has an independently
circulating heat medium. In order to allow the refrigerant of the
refrigeration cycle system and each heat medium of the two heat
transfer systems can exchange heat therebetween, an intermediate
heat exchanger is provided between the refrigeration cycle system
and each of the two heat transfer systems. Further, in order that
the heat medium of the heat transfer system that exchanges heat
with the heat-generating body and air taken into the vehicle
interior can exchange heat therebetween, an interior heat exchanger
is provided in the heat transfer system that exchanges heat with
the heat-generating body.
[0092] According to the embodiment described below, the heat energy
obtained through temperature control of the heat-generating body
can be utilized for interior air-conditioning to minimize energy
required for the interior air-conditioning, so that it is possible
to save energy for interior air-conditioning. In addition,
according to the embodiment described below, the heat energy
obtained through temperature control of the heat-generating body
can be utilized for the interior air-conditioning, so that the
energy saving effect of the interior air-conditioning can be
enhanced. Therefore, according to the embodiment described below,
the air-conditioning system can reduce energy that the
air-conditioning system takes out of the energy source of the
heat-generating body.
[0093] The air-conditioning system for a vehicle as mentioned above
is suitable for increasing the travel distance of EV 1000 per one
charging of the battery 100. The air-conditioning system for a
vehicle as mentioned above is suitable for reducing the capacity of
the battery 100 when the travel distance per one charging of the
battery 100 is equivalent to that of the conventional one. If the
capacity of the battery 100 is reduced, it may lead to a reduction
in cost of EV 1000, helping promotion of EV 1000 in the market, and
a reduction in weight of EV 1000.
[0094] According to the embodiment described below, the heat energy
used for interior air-conditioning can be utilized for temperature
control of the heat-generating body to control the temperature of
the heat medium for temperature control of the heat-generating body
in a wide range, so that the temperature of the heat-generating
body can be changed without being adversely affected by the
surrounding environment. Therefore, according to the embodiment
described below, the temperature of the heat-generating body can be
controlled to be an optimum temperature at which the
heat-generating body operates with high efficiencies, so that it is
possible to operate the heat-generating body at high
efficiencies.
[0095] The air-conditioning system for a vehicle as mentioned above
is suitable for reducing the cost of EV 1000. If EV 1000 is made to
be low-cost, it may facilitate EV 1000 to be more widely used.
[0096] (Overall Construction of Air-Conditioning System for a
Vehicle)
[0097] FIG. 1 is a diagram schematically showing a construction of
the air-conditioning system for a vehicle according to the present
invention. The air-conditioning system for a vehicle shown in FIG.
1 comprises a cooling/air-heating system 60 that performs
cooling/air-heating of the vehicle interior and equipment that
needs temperature control and a control device 61 that controls the
cooling/air-heating system 60. Various types of actuators provided
in the cooling/air-heating system 60 are controlled by control
signals from the control device 61. Examples of the actuators
associated with the present embodiment include the compressor 1,
expansion valves 22A, 22B, 23, four-way valve 20, three-way valve
21, circulation pumps 5A, 5B, exterior fan 3 and interior fan
8.
[0098] Informations on temperatures from a vehicle temperature
sensor 62, an equipment temperature sensor 63, a refrigerant
temperature sensor 64, and an external air temperature sensor 65
respectively are input to the control device 61, where the sensors
detect respective temperatures of temperature control objects.
According to the present embodiment, as the temperature control
objects, it is included: air in the vehicle interior and equipment
such as the motor, the inverter, the battery and the gearbox, each
of which is provided with a temperature sensor. To the control
device 61 is input vehicle speed information that indicates a
driving state of the vehicle from a vehicle speed sensor 66 and an
accelerator pedal depressing amount information from an accelerator
pedal sensor 67. Also, travel plan information of the vehicle (road
information, destination information and so on) is input to the
control device 61 from a navigation device 68.
[0099] (Cooling/air-heating system 60) FIG. 2 is a diagram showing
a schematic construction of the cooling/air-heating system 60. The
cooling/air-heating system 60 includes a refrigeration cycle
circuit 90 and an air-conditioning circuit 91A as an
air-conditioning system that controls the condition of air in the
vehicle interior and an equipment cooling circuit 91B as a
temperature control system that controls a temperature of a
heat-generating body such as battery 100, motor generator 200, and
inverter 300 shown in FIG. 19.
[0100] In the refrigeration cycle circuit 90 are circularly
connected compressor 1 that compresses the refrigerant 40, exterior
heat exchanger 2 that exchanges heat with external air, fluid
piping 12, and air-conditioning heat exchanger 4A. The
air-conditioning heat exchanger 4A exchanges heat with the
air-conditioning cooling medium 41A kept in the air-conditioning
circuit 91A. Between the intake piping 11 and the discharge piping
10 of the compressor 1 is provided the four-way valve 20. By
switching the four-way valve 20, either one of the intake piping 11
and the discharge piping 10 can be connected with the exterior heat
exchanger 2 and the other one can be connected with the
air-conditioning heat exchanger 4A. FIG. 1 illustrates air-cooling
operation; the four-way valve 20 connects the discharge piping 10
with the exterior heat exchanger 2 and the intake piping 11 with
the air-conditioning heat exchanger 4A.
[0101] The cooling heat exchanger 4B exchanges heat between the
refrigerant 40 of the refrigeration cycle circuit 90 and the
equipment cooling medium 41B. One end of the cooling heat exchanger
4B is connected with the fluid piping 12 and the other end thereof
is switchably connected with either one of the discharge piping 10
or the intake piping 11 of the compressor 1 through the three-way
valve 21. The fluid piping 12 is provided with the receiver 24. The
expansion valves 23, 22A, 22B that function as flow rate
measurement means are provided between the receiver 24 on the fluid
piping 12 and the exterior heat exchanger 2, between the
air-conditioning heat exchanger 4A and the receiver 24, and between
the cooling heat exchanger 4B and the receiver 24, respectively.
The exterior heat exchanger 2 is provided with the exterior fan 3
for blowing external air.
[0102] In the air-conditioning circuit 91A are circularly connected
interior heat exchanger 7A, circulation pump 5A, and
air-conditioning heat exchanger 4A in order. The interior heat
exchanger 7A exchanges heat with air that will be blown into the
vehicle interior. The circulation pump 5A circulates the
air-conditioning cooling medium 41A.
[0103] In the equipment cooling circuit 91B are circularly
connected interior heat exchanger 7B, temperature controlling
object equipment 9, circulation pump 5B, and cooling heat exchanger
4B in order. The interior heat exchanger 7B exchanges heat with air
that has flown out from the interior heat exchanger 7A. The
circulation pump 5B circulates the equipment cooling medium 41B
(for example, cooling water being used). According to the present
embodiment, examples of the temperature controlling object
equipment 9 include the motor, the inverter, the driving battery,
and gearbox.
[0104] The equipment cooling circuit 91B is provided with a bypass
circuit 30 that bypasses at both ends of the interior heat
exchanger 7B. The bypass circuit 30 is provided with a two-way
valve 25, and a main circuit 31 that passes through the interior
heat exchanger 7B is provided with the two-way valve 26. By opening
and closing actions of these two-way valves 25, 26, it is possible
to freely construct a flow channel of the equipment cooling medium
41B.
[0105] Then, the operational action of the cooling/air-heating
system 60 shown in FIG. 2 is explained. According to the present
embodiment, the circulation pump 5B is operated to perform
temperature control of the temperature controlling object equipment
9. The operations of other equipments vary according to a load of
air-conditioning and the heat generation amount of the temperature
controlling object equipment 9. Hereafter, explanation is made
about air-cooling operation, dehumidifying
(air-cooling/air-heating) operation, air-heating operation,
air-heating/cooling operation, and heating operation.
[0106] (Air-Cooling Operation)
[0107] Air-cooling operation means an operation mode in which both
the air-conditioning circuit 91A and the equipment cooling circuit
91B can be cooled by using the exterior heat exchanger 2 as a
condenser, and the air-conditioning heat exchanger 4A and the
cooling heat exchanger 4B as evaporators. In case of the
air-cooling operation, the four-way valve 20 and the three-way
valve 21 provided in the refrigeration cycle circuit 90 are
switched to a state shown by solid lines. That is, the discharge
piping 10 of the compressor 1 is connected with the exterior heat
exchanger 2 and the intake piping 11 of the compressor 1 is
connected with the air-conditioning heat exchanger 4A and the
cooling heat exchanger 4B.
[0108] The refrigerant 40 compressed by the compressor 1 radiates
heat at the exterior heat exchanger 2 to be liquefied and then
divided in the receiver 24 into a portion of the refrigerant that
flows into the air-conditioning heat exchanger 4A and a portion of
the refrigerant that flows into the cooling heat exchanger. The
portion of the refrigerant that flowed into the air-conditioning
heat exchanger is decompressed by the expansion valve 22A to have a
lower temperature and a lower pressure and then absorbs heat from
the air-conditioning cooling medium 41A of the air-conditioning
circuit 91A at the air-conditioning heat exchanger 4A to be
evaporated, returning to the compressor 1 through the four-way
valve 20. On the other hand, the portion of the refrigerant that
flowed into the cooling heat exchanger 4B is decompressed by the
expansion valve 22B to have a lower temperature and a lower
pressure and then absorbs heat from the equipment cooling medium
41B of the equipment cooling circuit 91B at the cooling heat
exchanger 4B to be evaporated, returning to the compressor 1
through the three-way valve 21.
[0109] By driving the circulation pump 5A provided in the
air-conditioning circuit 91A, the air-conditioning cooling medium
41A cooled at the air-conditioning heat exchanger 4A is supplied to
the interior heat exchanger 7A. When the interior fan 8 is driven,
the air that has exchanged heat at the interior heat exchanger 7A
and has been cooled is blown into the vehicle interior. When the
circulation pump 5B provided in the equipment cooling circuit 91B
is driven, the equipment cooling medium 41B heated by the
temperature controlling object equipment 9 is cooled by heat
exchange at the cooling heat exchanger 4B.
[0110] Since both the air-conditioning heat exchanger 4A and the
cooling heat exchanger 4B can be used as evaporators as mentioned
above, air-cooling of the vehicle interior and cooling of the
temperature controlling object equipment 9 can be realized
simultaneously. Furthermore, since the air-conditioning heat
exchanger 4A and the cooling heat exchanger 4B are connected with
the intake piping 11 of the compressor 1 in parallel and the
expansion valves 22A, 22B are provided in the respective
refrigerant circuits, the respective flow rates of the portions of
the refrigerant that flow in the air-conditioning heat exchanger 4A
and the cooling heat exchanger 4B can be changed freely. As a
result, the temperature of the equipment cooling medium 41B and the
temperature of the air-conditioning cooling medium 41A can be
controlled at any desired temperatures. Therefore, even when the
temperature of the air-conditioning cooling medium 41A is
sufficiently lowered in order to perform air-cooling, the
temperature of the equipment cooling medium 41B with which the
temperature controlling object equipment 9 is connected can be
maintained high by controlling the flow rate of the portion of the
refrigerant that flows into the cooling heat exchanger 4B.
[0111] The temperature of the equipment cooling medium 41B can be
controlled by controlling the opening of the expansion valve 22B.
In a simplified manner, the valve is relatively more opened when
the temperature of the equipment cooling medium 41B is high and the
valve is relatively more closed when the temperature is low.
[0112] The performance of the refrigeration cycle circuit 90 can be
controlled by regulating the rotational speed of the compressor 1
such that the temperature of the air-conditioning cooling medium
41A reaches a desired temperature. When it is determined that the
load of air-cooling is high, the target temperature of the
air-conditioning cooling medium 41A is lowered whereas when it is
determined that the load of air-cooling is low, the target
temperature of the air-conditioning cooling medium 41A is elevated.
By so doing, control of the air-conditioning performance in
response to the load can be achieved.
[0113] When no load of air-cooling is imposed and only cooling of
the temperature controlling object equipment is required, it is
necessary to use only the cooling heat exchanger 4B as an
evaporator by stopping the circulation pump 5A and the interior fan
8 and closing the expansion valve 22A and adjusting the opening of
the expansion valve 22B. This makes it possible to cool the
equipment cooling medium 41B, so that the temperature controlling
object equipment 9 can be cooled. In this case, the rotational
speed of the compressor 1 is controlled so that the temperature of
the equipment cooling medium 41B reaches the target temperature.
The amount of heat exchange may be changed by controlling the
rotational speed of the circulation pump 5A.
[0114] (Air-cooling/dehumidifying operation) In an
air-cooling/dehumidifying operation, the two-way valve 26 is opened
in the state shown in FIG. 2 to allow the equipment cooling medium
41B at a high temperature to flow into the main circuit 31 that is
provided with the interior heat exchanger 7B. When the equipment
cooling medium 41B at a high temperature is introduced in the
interior heat exchanger 7B as mentioned above, it is possible to
perform a so-called reheating and dehumidifying operation in which
the air that is cooled and dehumidified at the interior heat
exchanger 7A, after being heated at the interior heat exchanger 7B,
is blown into the vehicle interior. Since the air supplied to the
vehicle interior has a lower relative humidity, comfortableness of
the interior space can be improved.
[0115] The heat source of the interior heat exchanger 7B used as a
reheater is a so-called waste heat that is generated by the
temperature controlling object equipment 9. Therefore, unlike the
case where a heater or the like is used for reheating, it is
unnecessary to additionally introduce energy, so that the
comfortableness of the vehicle interior can be improved without
increasing power consumption.
[0116] The amount of reheat may vary depending on the temperature
and flow rate of the portion of the equipment cooling medium 41B
that flows into the main circuit 31. Accordingly, the amount of
reheat can be controlled by varying the amount of exchanged heat at
the cooling heat exchanger and the flow rate of the portion of the
equipment cooling medium 41B that flows into the main circuit 31.
In order to make variable the amount of exchanged heat of the
cooling heat exchanger 4B, the opening of the expansion valve 22B
may be controlled to control the flow rate of the portion of the
refrigerant that flows into the cooling heat exchanger 4B. When no
cooling is necessary, the expansion valve 22B may be fully
closed.
[0117] In order to make variable the flow rate of the portion of
the equipment cooling medium 41B that flows into the main circuit
31, combination of the switching conditions of the two-way valves
25, 26 may be changed. The ratios of flow rates of the portions of
the equipment cooling medium 41B that flows into the main circuit
31 and the bypass circuit 30 can be controlled freely by using, for
example, three-way valve instead of the two-way valves 25, 26.
[0118] (Air-Heating/Dehumidifying Operation)
[0119] FIG. 3 is a diagram illustrating an
air-heating/dehumidifying operation. In case when the amount of
reheat is insufficient in the air-cooling/dehumidifying operation,
the three-way valve 21 is switched as shown in FIG. 3 to perform an
air-heating/dehumidifying operation. In the
air-heating/dehumidifying operation, the equipment cooling medium
41B is heated by using the cooling heat exchanger 4B while keeping
the air-conditioning heat exchanger 4A for use as an evaporator. In
this case, the refrigerant compressed by the compressor 1 is
divided by the four-way valve 20 and the three-way valve 21,
flowing into the exterior heat exchanger 2 and the cooling heat
exchanger 4B. The respective portions of the equipment cooling
medium 41B are condensed and liquefied at the exterior heat
exchanger 2 and the cooling heat exchanger 4B, respectively, and
then converge in the receiver 24. Thereafter, the refrigerant
decompressed by the expansion valve 22A returns to the compressor 1
after it is evaporated and gasified at the air-conditioning heat
exchanger 4A.
[0120] Since the equipment cooling medium 41B can be heated by
using the cooling heat exchanger 4B as mentioned above, the amount
of reheat can be increased by using the refrigeration cycle circuit
90 even when the amount of reheat is insufficient. Also the heat
input from the cooling heat exchanger 4B is a portion of the heat
that has been discharged to the exterior air, so that no new heat
source is required. Therefore, there is no increase in power
consumption.
[0121] The refrigerant discharged from the compressor 1 is
condensed by using both the cooling heat exchanger 4B and the
exterior heat exchanger 2, so that the amount of reheat can be
changed freely by controlling the flow rates of the portions of the
refrigerant that flow into both the heat exchangers. Specifically,
the amount of discharged heat is controlled by varying the
rotational speed of the exterior fan 3 to control the flow rate of
the refrigerant that flows through the exterior heat exchanger 2.
Also, the flow rate of the refrigerant can be controlled by
decreasing the opening of the expansion valve 23. As a result, the
amount of exchanged heat at the cooling heat exchanger 4B can be
increased to increase the amount of reheat.
[0122] Under the condition that the performance of exchanging heat
of the exterior heat exchanger 2 becomes high, such as in the case
where the temperature of the exterior air is low or the air-stream
caused by driving hits the exterior heat exchanger 2, the amount of
heat discharged from the exterior heat exchanger 2 tends to
increase. For this reason, the amount of reheat can be increased by
reducing the rotational speed of the exterior fan 3 or decreasing
the opening of the expansion valve 23 based on the information from
the sensors such as the temperature of the external air and vehicle
speed.
[0123] As mentioned above, the amount of dehumidifying and the
amount of reheat can be controlled in the cooling system according
to the present embodiment. In concrete terms, a desired
dehumidifying amount is ensured by setting the temperature of the
cooling medium 41A for air conditioning to be a temperature
enabling the dehumidifying operation. On the other side, a reheat
amount is ensured by maintaining the temperature of the equipment
cooling medium 41B in an appropriate temperature, which is achieved
by controlling the flow rate of coolant flowing in the heat
exchanger 4B for cooling through control of rotational speed of the
interior fan 3 and opening of the expansion valves 23, 22B.
[0124] (Air-Heating Operation)
[0125] FIG. 4 is a diagram illustrating the system in an
air-heating operation. For the air-heating operation, there are two
operation modes depending on load of air-heating.
[0126] A first operation mode is a heat-radiating operation mode
when the load of air-heating is low and uses the heat released from
the temperature controlling object equipment 9 without using the
refrigeration cycle circuit for air-heating. In the heat-radiating
operation mode, the circulation pump 5B and the interior fan 8 are
started up and the two-way valve 26 is opened to introduce the
equipment cooling medium 41B into the interior heat exchanger 7B.
Since the equipment cooling medium 41B has been already heated by
the temperature controlling object equipment 9, the equipment
cooling medium 41B is cooled when it radiates heat to the air to be
blown into the vehicle interior at the interior heat exchanger 7B
and the air blown into the vehicle interior is heated. By using the
heat released from the temperature controlling object equipment 9
for air-heating, air-conditioning can be performed with reduced
energy consumption.
[0127] A second operation mode is an operation mode when the heat
released from the temperature controlling object equipment 9 is
insufficient for the load of air-heating, i.e., an
air-heating/heat-radiating operation mode in which the
refrigeration cycle circuit 90 is used in combination with the heat
released from the temperature controlling object equipment 9. In
this case, the four-way valve 20 provided in the refrigeration
cycle circuit 90 is switched as indicated by a solid line
connecting the discharge piping 10 of the compressor 1 with the
air-conditioning heat exchanger 4A and the intake piping 11 with
the exterior heat exchanger 2. That is, there is formed a cycling
in which the air-heating heat exchanger 41A works as a condenser
and the exterior heat exchanger 2 as an evaporator.
[0128] The refrigerant 40 compressed by the compressor 1 is
condensed and liquefied by radiating heat to the air-conditioning
cooling medium 41A at the air-conditioning heat exchanger 4A.
Thereafter, the liquefied refrigerant 40 is evaporated and gasified
by heat exchange with the exterior air at the exterior heat
exchanger 2 and returns to the compressor 1. The expansion valve
22B is full open and the cooling heat exchanger 4B is not used.
[0129] By starting up the circulation pump 5A, the air-conditioning
cooling medium 41A warmed with the heat of condensation from the
refrigerant 40 at the air-conditioning heat exchanger 4A flows into
the interior heat exchanger 7A, where the warmed refrigerant 40
releases heat to the air to be blown into the vehicle interior. The
air heated at the interior heat exchanger 7A is blown into the
vehicle interior space after it is further warmed up with the heat
gained from the equipment cooling medium 41B heated by the
temperature controlling object equipment 9 at the interior heat
exchanger 7B arranged on the downstream side of the flow of
air.
[0130] As mentioned above, the system is constructed such that the
air to be blown into the vehicle interior is further heated with
the heat released from the temperature controlling object equipment
9 after it is heated by the refrigeration cycle circuit 90. As a
result, the temperature of the air blown from the interior heat
exchanger 7A is kept low as compared with the temperature of the
air to be blown into the vehicle interior from the interior heat
exchanger 7B. That is, an air-conditioning apparatus that consumes
less energy can be constructed by utilizing heat released from the
temperature controlling object equipment 9 for air-heating.
[0131] By controlling the air-heating performance of the
refrigeration cycle circuit 90, the temperature of the equipment
cooling medium 41B can be controlled depending on the amount of
heat generated by the temperature controlling object equipment 9.
When the amount of heat generated by the temperature controlling
object equipment 9 increases, the temperature of the equipment
cooling medium 41B increases, and therefore the air-heating
performance of the refrigeration cycle circuit 90 is decreased. Due
to this, the amount of heat released from the interior heat
exchanger is decreased, and therefore the temperature of the air
that flows into the interior heat exchanger 7B becomes lower, so
that the amount of heat released from the equipment cooling medium
41B increases, resulting in suppression of temperature elevation of
the equipment cooling medium 41B. Conversely, when the amount of
heat generated by the temperature controlling object equipment 9 is
decreased, the temperature of the equipment cooling medium 41B is
lowered. Accordingly, the lowering of temperature of the equipment
cooling medium 41B can be suppressed by increasing the air-heating
performance of the refrigeration cycle circuit 90 to increase the
temperature of the air that flows into the interior heat exchanger
7B.
[0132] As a concrete example of controlling the performance of the
refrigeration cycle circuit 90, varying the rotational speed of the
compressor 1 may be referred. It is effective to control the
temperature of the equipment cooling medium 41B within a
predetermined temperature range for avoiding a trouble, for
example, that the temperature of the temperature controlling object
equipment 9 deviates from its operational temperature range.
[0133] (Air-Heating/Cooling Operation)
[0134] FIG. 5 is a diagram illustrating an air-heating/cooling
operation. As mentioned above, when the load of air-heating is
high, the target temperature of the equipment cooling medium 41B
may be set higher. However, when it is difficult to elevate the
target temperature of the equipment cooling medium 41B due to, for
example, the specification of the temperature controlling object
equipment 9, the air-heating performance cannot be increased. In
such a case, the air-heating/cooling operation as explained below
is performed to implement both the cooling of the equipment cooling
medium 41B and the heating of the air-conditioning cooling medium
41A simultaneously.
[0135] In the case of air-heating/cooling operation, like the
combined air-heating/heat radiating operation, there is formed a
cycling in which the air-conditioning heat exchanger 4A is used as
a condenser and the exterior heat exchanger 2 is used as an
evaporator, and additionally the expansion valve 22B is opened to
use the cooling heat exchanger 4B as an evaporator. The refrigerant
that is condensed and liquefied at the air-conditioning heat
exchanger 4A is divided into two portions in the receiver 24, one
of which is returned to the compressor 1 after it is decompressed
through the expansion valve 23 and evaporated at the exterior heat
exchanger 2. The other portion of the refrigerant is decompressed
through the expansion valve 22B and cools the equipment cooling
medium 41B at the cooling heat exchanger 4B to be evaporated and
gasified, and then returned to the compressor 1 through the
three-way valve 21.
[0136] In the air-heating/cooling operation, the heat released from
the temperature controlling object equipment 9 is recovered at the
cooling heat exchanger 4B as a heat source for the refrigeration
cycle circuit 90, transferred in the air-conditioning circuit at
the air-conditioning heat exchanger 4A and released to the vehicle
interior from the interior heat exchanger 7A. As explained, it is
possible to recover the heat released by the temperature
controlling object equipment 9 and to use the recovered heat for
air-heating, while controlling the temperature of the temperature
controlling object equipment 9. Since it is possible to absorb heat
from external air by using the exterior heat exchanger 2, the
air-heating performance can be increased.
[0137] Since the expansion valve 23 is provided between the fluid
piping 12 and the exterior heat exchanger 2, it becomes possible to
individually control the amount of heat absorbed from the equipment
cooling medium 41B and the amount of heat absorbed from the
external air by controlling the openings of the expansion valves
22B and 23, respectively. It should be noted that when the
temperature of the equipment cooling medium 41B becomes lower than
the temperature of the air-conditioning cooling medium 41A, the air
heated at the interior heat exchanger 7A would be cooled at the
interior heat exchanger 7B. In such a case, the two-way valve 26 is
closed while the two-way valve 25 is opened in the equipment
cooling circuit 91B to allow use of the bypass circuit 30. This
prevents the air to be blown into the vehicle interior from being
cooled by the cooling medium cooled at the cooling heating
exchanger 4B.
[0138] In case when the load of air-heating is lowered and the
air-heating/cooling operation is changed to a combined
air-heating/heat-radiating operation, there is the possibility that
there occurs a trouble, for example, that the blowing temperature
becomes low if the temperature of the equipment cooling medium 41B
is low. Therefore, it is desirable to increase the temperature of
the equipment cooling medium 41B before the operation mode change.
This can be achieved by controlling the opening of the expansion
valve 22B, since the temperature of the equipment cooling medium
41B can be controlled by making variable the amount of heat
exchange of the cooling heat exchanger 4B. In case when it is
detected that the temperature of the air-conditioning cooling
medium 41A becomes lower than the temperature of the equipment
cooling medium 41B, while keeping the temperature of the equipment
cooling medium during the air-heating/cooling operation, then it
may be judged that the load of air-heating is decreased, which may
allow to change the operation mode of the system from the
air-heating/cooling operation to the combined air-heating/heat
radiating operation mode.
[0139] (Heating Operation)
[0140] Upon starting up of the system when the external air
temperature is low as in winter seasons, the temperature of the
equipment cooling medium 41B is low so that it cannot be used for
air-heating immediately after its starting up, and therefore it is
necessary to wait for a while until the temperature of the
equipment cooling medium 41B increases with the heat released from
the temperature controlling object equipment 9. In such a case, the
expansion valve 22B is closed in the cycling shown in FIG. 5 to
perform an air-heating operation by using the interior heat
exchanger 7A. Also, a cycling is constructed in which the heat
exchange does not occur at the interior heat exchanger 7B between
the equipment cooling medium 41B of low temperature and the blown
air into the vehicle interior, for which two-way valve 26 is closed
and the two-way valve 25 is opened.
[0141] In case it is desired to rapidly increase the temperature of
the equipment cooling medium 41B when the amount of heat generated
by the temperature controlling object equipment 9 is small, the
three-way valve 21 is switched as shown in FIG. 6. With this
construction, the refrigerant 40 discharged from the compressor 1
flows into both the air-conditioning heat exchanger 4A and the
cooling heat exchanger 4B, so that the equipment cooling medium 41B
can be heated by using condensation heat of the portion of the
refrigerant 40 that has flown into the cooling heat exchanger 4B.
In this cycling, the expansion valves 22A, 22B are fully opened and
the refrigerant is decompressed by controlling the opening of the
expansion valve 23 and the heat from the external air is absorbed
at the interior heat exchanger 2. The two-way valve 26 is closed
and the two-way valve 25 is opened to use the bypass circuit.
[0142] Since it is possible to heat the equipment cooling medium
41B by using the refrigeration cycle as mentioned above, the
function can be implemented that the temperature of the temperature
controlling object equipment 9 is rapidly increased to a desired
temperature. As an alternative, either the flow rate of the
circulation pump 5B may be decreased or the circulation pump 5B may
be stopped. In this case, the amount of heat exchange with the
equipment cooling medium 41B can be suppressed, so that the
temperature of the temperature controlling object equipment 9 can
be rapidly increased.
[0143] As mentioned above, when installing on EV 1000 the
air-conditioning system for a vehicle that includes a temperature
adjustment system and an air-conditioning system in an integrated
fashion, it may be expected that the piping that constitutes flow
paths and the components are arranged within a narrow installation
space in a complicated manner. Taking into consideration
maintainability and necessary size- and cost reduction for the
air-conditioning system for a vehicle, and so on, it is desirable
to simplify the construction of the system by size reducing, number
decreasing or sharing of components when mounting the
air-conditioning system for a vehicle on EV 1000.
[0144] Accordingly, the circulation path of first heat transfer
system (equipment cooling circuit 91B) in which a heat medium for
controlling the temperature of the heat-generating body circulates,
which is thermally connected to the refrigeration cycle system
(refrigeration cycle circuit 90) with refrigerant circulated
through a first intermediate heat exchanger (cooling heat exchanger
4B), and the circulation path of a second heat transfer system
(air-conditioning circuit 91A) in which a heat medium for
controlling the air condition in the vehicle interior is
circulated, which are thermally connected to the refrigeration
cycle system through a second intermediate heat exchanger
(air-conditioning heat exchanger 4A), are made to communicate with
each other, and a reservoir tank (receiver 2) for regulating the
pressure in the circulation path of the first and second heat
transfer systems is provided such that it is common to both the
first and second heat transfer systems.
[0145] In the above-mentioned air-conditioning system for a
vehicle, the components thereof can be used in common to the first
and second heat transfer systems, so that the air-conditioning
system for a vehicle can be simplified in construction. The
simplification of the construction of the air-conditioning system
for a vehicle leads to improvement of maintainability of the
air-conditioning system for a vehicle installed in EV 1000 and
contributes to size reduction and cost reduction of the
air-conditioning system for a vehicle.
[0146] A drainage mechanism for draining heat medium that flows
through the circulation systems of the first and second heat
transfer paths may be provided in common to the first and second
heat transfer systems.
[0147] In the case of EV 1000 on which the air-conditioning system
for a vehicle is mounted, when a further size reduction and a
further increase in output power of the heat-generating body are
required, it is necessary to further increase the performance of
the system to cool the heat-generating body in order to cope with
that requirement. In this case, as an alternative, it may be
considered to further increase in performance of the system to cool
the heat-generating body by additional heat exchangers or by
increasing the capacity of the heat exchanger. However, taking into
consideration the necessity of size- and cost reduction, it is
desirable that the further increase in performance is achieved
without additional heat exchangers or increase in capacity of the
heat exchanger.
[0148] To this end, the air-conditioning system for a vehicle may
be provided with a circulation path connection control unit, such
that the circulation path of first heat transfer system (equipment
cooling circuit 91B) in which a heat medium for controlling the
temperature of the heat-generating body circulates, which is
thermally connected to the refrigeration cycle system
(refrigeration cycle circuit 90) with the refrigerant circulated
through a first intermediate heat exchanger (cooling heat exchanger
4B), and the circulation path of second heat transfer system
(air-conditioning circuit 91A) in which a heat medium for
controlling the air condition in the vehicle interior is
circulated, which is thermally connected to the refrigeration cycle
system through a second intermediate heat exchanger
(air-conditioning heat exchanger 4A), can be connected in series to
each other. When it is requested to make the heat exchange amount
of the heat medium supplied to the heat-generating body larger than
the heat exchange amount of the heat medium with the refrigerant by
one intermediate heat exchanger, the connection of the circulation
paths of the first and second heat transfer systems is controlled
by the circulation path connection control unit such that the heat
medium supplied to the heat-generating body flows through the first
and second intermediate heat exchangers in series.
[0149] Alternatively, the air-conditioning system for a vehicle may
be provided with a circulation path connection control unit, by
which the circulation path of first heat transfer system, which is
thermally connected through a first intermediate heat exchanger to
the refrigeration cycle system with circulating refrigerant and
through which a heat medium circulated for controlling the
temperature of two heat-generating bodies, is connected to one of
the two heat-generating bodies, and the circulation path of second
heat transfer system, which is thermally connected through a second
intermediate heat exchanger with the refrigeration cycle system and
through which a heat medium for controlling the air condition in
the vehicle interior is circulated, is connected to the other one
of the two heat-generating bodies, respectively. Then, the
connection of the circulation paths is switched by a circulation
paths connection switching unit such that the heat medium of the
first heat transfer system is supplied to one of the
heat-generating bodies and the heat medium of the second heat
transfer system is supplied to the other of the heat-generating
bodies. The amount of heat exchange between the two heat-generating
bodies and the heat media of the first and second heat transfer
systems is larger than the amount of heat exchange between the two
heat-generating bodies and the heat medium of the first heat
transfer system.
[0150] With the above-mentioned air-conditioning system for a
vehicle, the heat exchange amount between the heat-generating
bodies can be increased, so that the performance of the system for
temperature control of the heat-generating bodies can be increased.
As a result of improvement of the performance of the system with
respect to temperature control of the heat-generating bodies, when
a further size reduction and a further increase in output are
demanded, it is possible to meet such a demand. In addition, the
demand is accommodated without increase in size of the
air-conditioning system for a vehicle.
[0151] In the case of EV 1000 shown in FIG. 19, explanation is made
on an example in which the motor generator 200 and the inverter 300
are separate. However, the motor generator 200 and the inverter 300
may be integrated into one body, for example, by fixing the casing
of the inverter 300 on the casing of the motor generator 200 to
integrate them. In case where the motor generator 200 and the
inverter 300 are integrated, arrangement piping in which heat
medium for temperature adjustment flows becomes easier, so that the
air-conditioning system for a vehicle can be constructed more
simply.
[0152] [Concrete Example of Temperature Controlling Object
Equipment 9]
[0153] The temperature controlling object equipment 9 provided in
the equipment cooling circuit 91B is an equipment which is
installed in the vehicle and must be temperature controlled to be
within a predetermined range during the vehicle driving. As
concrete examples of the temperature controlling object equipment
9, a motor for driving, an inverter for driving the motor, a
battery for driving, a speed reduction mechanism (gearbox), and so
on, may be referred.
[0154] FIG. 7 shows a cooling structure of a gearbox. In FIG. 7(a),
a case 50 that accommodates therein gears G1, G2 is filled with
lubricating oil 51. In a lubricating oil pool, the piping 52 for
the cooling medium 41B is arranged to cool or warm the lubricating
oil 51 directly. As shown in FIG. 7(b), a conduit 53 for the
equipment cooling medium 41B may be formed directly in the case 50
of the gearbox.
[0155] In case where temperature control is performed by providing
the equipment cooling circuit 91B with the temperature controlling
object equipment 9, temperature control must be performed depending
on the thermal property of each of equipment. FIG. 8 is a figure
showing conditions of temperature control for each object of
temperature controlling. As examples of objects for temperature
controlling, the vehicle interior and the temperature controlling
object equipment 9 may be referred. As for the temperature
controlling object equipment 9, temperature control conditions of
the motor, inverter, battery and gearbox are shown.
[0156] (Vehicle Interior)
[0157] Regarding the air-conditioning of the vehicle interior,
air-cooling/air-heating and dehumidifying are performed
appropriately based on temperature settings, external air
temperature and so on. However, as described later, sometimes
air-cooling is stopped or weakened for cooling the temperature
controlling object equipment 9.
[0158] (Motor and Inverter)
[0159] The efficiencies of the motor and the inverter may vary
depending on their temperature. Generally, it is known that if the
torque and number of rotations are the same, the lower the
efficiencies are, the higher the temperatures are. Due to this, the
temperatures of the motor and the inverter is changed, through
which the efficiency of a motor or an inverter is changed; in
temperature control, only cooling is performed. The temperature of
the equipment cooling medium 41B supplied to the motor and the
inverter is controlled to be, for example, not higher than
60.degree. C.
[0160] (Battery)
[0161] In order to fully exploit the battery capacity of
charging/discharging, i.e. in order to optimize the efficiency of
charging/discharging, it is necessary for the battery temperature
to be kept within a predetermined temperature range. To this end,
warming is necessary when the battery temperature is low (for
example, upon start-up when the external air temperature is low),
whereas cooling is necessary when the battery temperature becomes
too high due to heat generation by the battery itself. The
temperature range in which the battery can efficiently operate
varies for the type of the battery; in the case of lithium ion
batteries, they can operate efficiently within the range of
20.degree. C. to 30.degree. C.
[0162] (Gearbox)
[0163] In the case of the gearbox as shown in FIG. 7, the viscosity
of the lubricating oil 51 in the case gives adverse effects,
causing loss upon driving. When the temperature of the lubricating
oil 51 is low (as in the case of start-up when the external air
temperature is low), the churning loss of the gears G1, G2
increases. Conversely, in case when the temperature of the
lubricating oil is too high, oil film formation on meshing surfaces
of the gears G1, G2 becomes insufficient, leading to increase of
friction loss. Therefore, upon start-up in winter seasons and so
on, warming becomes necessary. On the other hand, when the
temperature of the lubricating oil is high, it becomes necessary to
enhance heat radiation from the gearbox. The temperature of the
lubricating oil is controlled to be within the temperature range
of, for example, 30.degree. C. to 100.degree. C.
[0164] [Arrangement of Temperature Controlling Object Equipment
9]
[0165] FIGS. 9, 10 are figures illustrating an arrangement of a
plurality of pieces of temperature controlling object equipment 9.
In case where a plurality of pieces of temperature controlling
object equipment 9A to 9D is provided in the equipment cooling
circuit 91B, there are two structures, i.e., a structure of series
arrangement as shown in FIG. 9 and a structure of parallel
arrangement as shown in FIG. 10.
[0166] In case where the plurality of pieces of temperature
controlling object equipment 9A to 9D is arranged in series, the
heat-generating bodies are arranged so that the higher the setup
temperature of an heat-generating body is, the more to upstream
side with respect to the flow of the equipment cooling medium 41B
the heat-generating body is arranged. Here, let us consider a case
in which an inverter, a motor, a battery, and a gearbox are
provided as the temperature controlling object equipment 9A to 9D.
In this case, among the setup temperatures for them, the setup
temperature for the inverter 9A is the lowest and the setup
temperature increases for the motor 9B, the battery 9C
(corresponding to the battery 100 in FIG. 1), and the gearbox 9D in
this order.
[0167] FIG. 9 illustrates the case of the above-mentioned
air-cooling operation, in which the equipment cooling medium 41B is
cooled by the refrigerant 40 of the refrigeration cycle circuit 90
at the cooling heat exchanger 4B. This causes the equipment cooling
medium 41B that has a low temperature to flow into the inverter 9A.
Each time when the equipment cooling medium 41B passes each piece
of equipment 9A to 9C, the equipment cooling medium 41B absorbs
heat from the equipment to become a higher temperature. That is,
the temperature of the equipment cooling medium 41B at the inlet of
each piece of equipment 9A to 9D becomes higher in order of the
pieces of equipment 9A to 9D. It should be noted that in the
construction shown in FIG. 9, in case when the battery 5C and the
gearbox 5D are warmed (equipment heating operation), the motor 9B
and the inverter 9A are also warmed.
[0168] On the other hand, in case where the temperature controlling
object equipments 9A to 9D are arranged in parallel, the equipments
that require warming (the battery 9C, the gearbox 9D) and the
equipments that do not require warming (the inverter 9A, the motor
9B) are arranged so as to be in separate circuits as shown in FIG.
10. In the example shown in FIG. 10, a line in which the inverter
9A and the motor 9B are arranged in series, a line in which only
the battery 9C is arranged, and a line in which only the gearbox 9D
is arranged are connected in parallel. On the inlet sides of the
lines are provided two-way valves 35a to 35c, respectively. With
this arrangement, every line can be controlled to be in an optimum
temperature.
[0169] FIG. 10 shows the case of air-cooling operation. In case
where each of the equipment is cooled, the two-way valves 35a to
35c provided on the respective lines are opened to introduce the
equipment cooling medium 41B into each of the equipment. It should
be noted that in the case of air-heating/cooling operation shown in
FIG. 5, each of the equipment can be cooled. In case when the
battery 9C and the gearbox 9D are warmed, the heating operation
shown in FIG. 6 is performed; the two-way valves 35b, 35c are
opened to cause the cooling medium 91B that is in a high
temperature to flow in.
[0170] All the plurality of pieces of temperature controlling
object equipment 9A to 9D can be arranged in parallel to each
other. However, this is not desirable since the number of
components increases. The battery 9C and the gearbox 9D may be
arranged in series. However, it is preferred to arrange them in
separate lines in parallel like the construction shown in FIG. 10,
taking into consideration the situation of how the components are
mounted on the vehicle in that the battery 9C is arranged beneath
the seats and the gearbox 9D is arranged near the driving
shaft.
[0171] According to the present embodiment, use of the
cooling/air-heating system 60 having the above-mentioned
construction enables control of vehicle interior air-conditioning
and the cooling and warming of the equipment such as the motor and
the inverter individually. The control device 61 controls the
cooling/air-heating system 60 so that the temperature of the
vehicle interior and the temperature of the equipment become at
their setup temperatures, respectively.
[0172] [Temperature Control for Vehicle Interior and Equipment]
[0173] According to the present invention, as shown in FIG. 1, the
control device 61 acquires operation information of the vehicle
(speed information, accelerator pedal depressing amount
information, etc.) and travel plan information and controls the
cooling/air-heating system 60 based on the acquired information as
well as on the detected temperature of each object of temperature
control and on the detected temperature of the cooling medium. For
example, variations in temperature of each of the temperature
controlling object equipment and of the cooling medium are
predicted and the cooling and warming of each of the equipment is
performed efficiently by changing the setup temperatures of the
cooling media 41A, 41B based on the prediction to control the
temperature of the equipment to become optimal.
[0174] (Explanation of Control Operation)
[0175] FIG. 11 is a flowchart illustrating a control processing
program in the control device 61. The microcomputer provided in the
control device 61 performs the processing shown in FIG. 11 by
software installed therein. The microcomputer starts the processing
of the program illustrated in FIG. 11 when the ignition key switch
of the vehicle is turned on.
[0176] In step S1, an initial setup temperature of the
air-conditioning cooling medium 41A used for the air-conditioning
of the vehicle interior and an initial setup temperature of the
equipment cooling medium 41B used for cooling/warming of the
equipment 9A to 9D (FIG. 9) are determined. As the initial setup
temperature, it may be assumed a temperature that is suitable for
vehicle driving on a level road at a predetermined speed at a
normal temperature of the external air. FIG. 12 shows a
relationship between the temperature of the external air and the
air-conditioning of the vehicle interior and each of the
equipment.
[0177] In step S2, it is determined whether a command to drive the
air-conditioning system has been received. In the case of a
construction in which the driving of the air-conditioning system is
turned on/off by turning on/off of the driving of the vehicle,
whether a command to drive the air-conditioning system has been
received is determined based on on/off of the vehicle drive on/off
switch. If the result of the determination in step S2 is YES, the
program illustrated in FIG. 11 is ended. On the other hand, if the
result of the determination in step S2 is NO, the process proceeds
to step S3.
[0178] In step S3, temperature variations of the vehicle interior,
the temperature controlling object equipments 9A to 9D, and the
cooling media 41A, 41B are predicted based on at least one of the
driving information, the travel plan information, the detected
temperature of each of the temperature controlling object
equipment, and the detected temperature of the cooling medium.
[0179] Here, an example of prediction of temperature variation is
explained with reference to FIG. 13. In FIG. 13, (a) illustrates a
change in accelerator pedal depressing amount, (b) illustrates the
temperature variation of the motor or the inverter, and (c)
illustrates the temperature variation of the equipment cooling
medium 41B. In each of (a), (b) and (c), the horizontal axis
indicates time, with the position t2 indicated in broken line
representing present time. Filled circles in FIG. 13(b), (c)
indicate actually measured temperatures.
[0180] As shown in FIG. 13(a), the accelerator pedal depressing
amount is increased between time t0 and time t1 to change from
value A1 to value A2. After time t1, it is maintained at the value
A2. When the accelerator pedal depressing amount is changed from A1
to A2 (>A1) as mentioned above, the motor output increases and
at the same time the heat generation amounts of the motor and the
inverter increase, so that the temperature of motor/inverter is
varied as shown in FIG. 13(b). Further, the temperature of the
cooling medium 41B that cools the motor/inverter shows a tendency
of variation similar to that of the temperature of the
motor/inverter as shown in FIG. 13(c).
[0181] The temperature of the motor/inverter and the temperature of
the cooling medium are in an upward trend at present time (time
t2). When the temperature of the motor/inverter and the temperature
of the cooling medium are predicted based on the temperature of the
motor/inverter and the temperature of the cooling medium as well as
the accelerator pedal depressing amount shown in FIG. 13(a), there
are obtained respective predicted temperatures as shown in FIG.
13(b), (c) in solid lines.
[0182] The setup temperature T1 shown in FIG. 13(c) is a setup
temperature upon performing temperature control of the equipment
cooling medium 41B (target temperature) and the temperature is
controlled to be at the setup temperature T1 up to the present time
(t2). That is, upon calculating a predicted temperature (solid
line), the setup temperature T1 is used. The predicted temperature
(solid line) is still increasing on or after present time (t2), so
that it is predicted to exceed the setup temperature T1 within the
predetermined time .DELTA.t.
[0183] In the case of the conventional air-conditioning system, at
the time when the actually measured temperature of the cooling
medium exceeds the setup temperature T1, or the temperature of the
motor/inverter exceeds the target temperature, the system is
configured so that the cooling performance by the equipment cooling
medium 41B is increased to lower the temperature of the
motor/inverter. As a result, there is the possibility that the
motor does not output a power corresponding to the accelerator
pedal depressing amount A2, since there is a time delay from the
time when the accelerator pedal depressing amount is changed from
A1 to A2 to the time when the temperature of the cooling medium
exceeds the setup temperature T1 and since it takes some time for
the temperature of the cooling medium to be lowered sufficiently
after it has once exceeded the setup temperature T1.
[0184] Then, according to the present embodiment, if the predicted
temperature at a time point when a predetermined time .DELTA.t has
elapsed from a predicted time (t2) exceeds the setup temperature T1
of the present time, the setup temperature is set at a lower
temperature T2 (<T1). As a result, the actual temperature change
of the cooling medium becomes smaller than the temperature change
of the predicted temperature (solid line), so that a desired motor
output can be achieved with sufficient margin. Since the
air-conditioning with a high performance can be started in advance,
it is possible to cope with the temperature change of the equipment
(the motor, the inverter). By changing the setup temperature in
earlier phase, an abrupt increase in the rotational speed of the
compressor 1, the exterior fan 3, the interior fan 8, and the
circulation pump 5B can be prevented, so that sound noises can be
suppressed.
[0185] The broken line shown in FIG. 13(a) indicates the case in
which the accelerator pedal depressing amount is returned to A1
again after it is increased to A2. In this case, the time in which
the accelerator pedal depressing amount A2 is maintained is short,
so that the predicted temperature becomes as indicated in broken
line in FIG. 13(c). Though the temperature of the cooling medium at
present (time t2) is not so different from that of the
above-mentioned case, the information of accelerator pedal
depressing amount (i.e. driving information) at present differs
largely as shown with the solid line and the broken line in FIG.
13(a), so that when prediction is performed taking such driving
information into consideration, the predicted temperature of the
cooling medium may differ greatly. As a result, controlling of the
setup temperature based on the predicted temperature differ between
both cases.
[0186] Turning back to the flowchart shown in FIG. 11, in step S4,
it is determined whether it is necessary to change the setup
temperature of the cooling medium 41A, 41B based on the predicted
temperature change obtained in step S3. For example, in a scene
where the performance of cooling is increased as mentioned above,
whether it is necessary to change the setup temperature is
determined by determining whether the predicted temperature after
the predetermined time .DELTA.t has elapsed exceeds the setup
temperature at present.
[0187] If it is determined in step S4 that the change is necessary,
the process proceeds to step S5 to change the setup temperature of
the cooling medium. Thereafter, the process proceeds to step S6. On
the other hand, if it is determined that no change is necessary as
the predicted temperature as shown in the broken line in FIG. 13(c)
is calculated, step S5 is skipped and the process proceeds to step
S6.
[0188] In step S6, each actuator of the cooling/air-heating system
60 as shown in FIG. 1 is controlled so that the temperature of the
cooling medium at present will be changed based on the changed
setup temperature. In the case of the example shown in FIG. 13, the
temperature of the equipment cooling medium 41B is controlled to be
lowered corresponding to the increase in the accelerator pedal
depressing amount, i.e. corresponding to increase in motor output,
the actuator is controlled so that the cooling performance of the
equipment cooling circuit 91B can be increased.
[0189] In the above-mentioned explanation, though the setup
temperature of the cooling medium is changed in step S4 to step S6,
it is acceptable that the setup temperature of the temperature
controlling object (vehicle interior, each of equipment) is
changed. In step S6, the cooling/air-heating system 60 is
controlled based on the setup temperature of each temperature
controlling object.
[0190] FIG. 14 illustrates a concrete processing in case where the
cooling performance of the equipment is increased in step S6. In
step S611, there is implemented at least one of the followings for
increase in cooling performance; an increase in rotational speed of
the compressor 1, an increase in flow rate of the circulation pump
5B, and an increase in rotational speed of the exterior fan 3. When
the rotational speed of the compressor 1 is increased or the
rotational speed of the exterior fan 3 is increased, the cooling
performance of the equipment cooling medium 41B with the
refrigeration cycle is increased. By increasing the flow rate of
the circulation pump 5B, heat absorption from the motor, which is a
temperature controlling object equipment 9, to the equipment
cooling medium 41B and heat release from the equipment cooling
medium 41B to the refrigerant 40 increase, respectively.
[0191] In step S612, it is determined whether it is necessary to
further increase the cooling performance in addition to the
increase in cooling performance in step S611. If the result of the
determination in step S612 is YES, the process proceeds to step
S613 to open the two-way valve 26 in the equipment cooling circuit
91B to cause the equipment cooling medium 41B to flow into the
interior heat exchanger 7B and increase the rotational speed of the
interior fan 8. It should be understood that if the interior
air-conditioning is off, the interior fan 8 is turned on. In this
way, heat emission from the equipment cooling medium 41B to the
vehicle interior is increased to improve removal of heat from the
motor.
[0192] Since warm air flows into the vehicle interior as a result
of the control in step S613, the effect of air-cooling is weakened
when the vehicle interior is air-cooled whereas the effect of
air-heating is enhanced if the vehicle interior is air-heated. Even
if the interior air-conditioning is off, it may sometime happen
that the interior fan 8 automatically starts rotation to blow out
warm air into the vehicle interior, making the driver
uncomfortable. To avoid such uncomfortableness, an air venting
channel may be arranged to prevent air from flowing into the
vehicle interior. The same will do in case the air-cooling
performance or air-heating performance of the vehicle interior, or
the warming performance of the equipment is increased.
[0193] FIG. 14 illustrates a control when the compressor 1, the
circulation pump 5B, and the exterior fan 3 are variably
controlled, wherein in the case that the compressor 1, the
circulation pump 5B, and the exterior fan 3 are configured to be
on/off controlled, then at least one of the compressor 1, the
circulation pump 5B, and the exterior fan 3 is turned from off to
on as in step S611 in FIG. 15.
[0194] On the other hand, in case that the cooling performance is
decreased in step S6 in FIG. 11, controlling such as that shown in
FIG. 16 is performed. In FIG. 16, (a) indicates the case where the
compressor 1, the circulation pump 5B, and the exterior fan 3 are
variably controlled, and (b) indicates the compressor 1, the
circulation pump 5B, and the exterior fan 3 are on/off controlled.
In the case of FIG. 11(a), in step S621, there is performed at
least one of a decrease in rotational speed of the compressor 1, a
decrease in flow rate of the circulation pump 5B, and a decrease in
rotational speed of the exterior fan 3. On the other hand, in step
S621, at least one of the compressor 1, the circulation pump 5B,
and the exterior fan 3 is turned from on to off.
[0195] In the above-mentioned explanation of FIG. 13, prediction of
temperature in a situation where the accelerator pedal press-down
amount is changed and the change of the setup temperature of the
equipment cooling medium 41B are explained, and in FIG. 17
summarized are other situations. In FIG. 17shown are for settings
that the setup temperature of the temperature controlling object
(vehicle interior, each of temperature controlling object
equipment) is changed.
[0196] The states of the vehicle are determined, based on detection
signals from the accelerator sensor 66 and vehicle speed sensor 67
as driving information and the travel plan information from the
navigator 68. In FIG. 17, nine types of vehicle states are
described, which include "charging", "before start driving",
"before start moving", "before and during acceleration/deceleration
and driving on sloping roads", "driving on non-motorways", "before
entering and during running on motorways", "before temporary stop
(for example, waiting at stoplights, jam-up, etc.)", "before stop",
and "stopped". However, the vehicle states are not limited thereto.
The objects of air-conditioning include the vehicle interior, the
motor, the inverter, the batteries, and the gearbox.
[0197] As in the case shown in FIG. 13, the intention (to
accelerate or the like) of the driver can be determined from the
driving information (vehicle speed, accelerator pedal depressing
amount). The travel plan information includes road information
(jam-up, slope of road) on the way to the destination and
destination information given by the navigation device 68. The
amount of heat generation of the temperature controlling object
equipment is predicted based on the output of the motor and output
of the interior air-conditioning expected from the above, and the
setup temperature of the vehicle interior as well as the setup
temperature of the temperature controlling object equipment are
changed.
[0198] For example, the intention of acceleration can be predicted
from the driving information as shown in FIG. 13. In that case, the
setup temperatures of the motor and the inverter are set low in
order to cool the motor and the inverter. In case when driving on
sloping roads are predicted from the travel plan information (the
fourth column from above in FIG. 17), the setup temperatures of the
motor and the inverter are set lower than those initially set. The
initial setting is made, for example, assuming ordinary driving on
a level road. The setup temperature of the battery is not changed,
and warming or cooling is performed by controlling the flow of the
cooling medium 41B so that the temperature of the battery falls
within a predetermined temperature range that enables efficient
charging/discharging (structure in FIG. 10). The setup temperature
of the gearbox is not changed and the released heat is
recovered.
[0199] During charging as shown in FIG. 17 (first column), the
setup temperature is not changed and warming/cooling is controlled
so that the battery temperature during charging falls within the
predetermined temperature range. For the vehicle interior, the
motor, the inverter, and the gearbox, cooling/air-heating or
cooling/warming is not performed.
[0200] "Before start driving" given in the second column of FIG. 17
is for the case when the battery is charged from an AC power source
by parking. In this case, cooking/air-heating of the vehicle
interior is performed with the AC power source so that the
temperature of the vehicle interior falls within a comfortable
temperature range at the time of start of running.
[0201] FIG. 18 is a drawing that explains this vehicle state. Upon
charging, a commercial power source or the AC power source 81 of
the charging station is connected to the charger 82 installed in
the vehicle 80. Two DC lines 84, 85 extend from the charger: the DC
line 84 is connected with the battery 9C and the DC line 85 is
connected with the cooling/air-heating system 60 via the switch
unit 83. The cooling/air-heating system 60 can be driven either by
the battery 9C installed in the vehicle or by the external AC power
source by switching them by the switch unit 83.
[0202] Upon charging before driving, the switch unit 83 is switched
so that the charger 82 and the cooling/air-heating system 60 are
connected with each other. During charging the battery, the
cooling/air-heating system 60 is driven by using the external AC
power source 81 to perform air-conditioning
(air-cooling/air-heating) of the vehicle interior. The battery 9C
is cooled/warmed so that the battery temperature during charging
becomes within the predetermined temperature range. Regarding the
gearbox, when the oil temperature is low, warming is performed in
order to prepare for driving. The setup temperatures of the vehicle
interior, the battery and the gearbox are not changed.
[0203] As mentioned above, the power of battery is not used for
driving the cooling/air-heating system 60, and therefore charging
of the battery is completed in a short time and efficiently. The
battery temperature is controlled to be within the predetermined
range by the cooling/air-heating system 60, so that the efficiency
of charging is improved.
[0204] Also during the charging, as shown in the first column of
FIG. 17, the power from the external power source instead of the
power of the battery may be used to drive the cooling/air-heating
system 60 upon controlling temperature so that the battery
temperature falls within the predetermined temperature range.
[0205] In the vehicle state (before star moving) described in the
third column of FIG. 17, cooling/warming of the battery and warming
of the gearbox are performed by keeping all the setup temperatures
of the temperature controlling objects as unchanged in order to
prepare for driving taking place immediately thereafter. As in the
vehicle states described in the second and third columns (before
start driving, before start moving), by warming the battery and the
gearbox before driving the vehicle, the improvement of efficiency
upon running can be achieved.
[0206] As in the vehicle state described in the fifth column of
FIG. 17 (upon running on non-motorways), that is, in the standard
vehicle state, the setup temperatures of all the temperature
controlling objects are kept as unchanged.
[0207] Also in the vehicle state described in the sixth column of
FIG. 17 (before entering and driving on motorways), like the
running on sloping roads, the motor output power becomes large, so
that the setup temperature and controlling of air-conditioning
similar to the case of the vehicle state described in the fourth
column are used.
[0208] The vehicle state described in the seventh column of FIG. 17
corresponds to the case where a temporary stop such as waiting at
stoplights or upon jam-up is predicted from the travel plan
information. In the state that the vehicle is in a temporary stop
state, the heat generation amount from the motor and the inverter
is smaller than that of the running state, and the temperature will
not increase with lower cooling performance. Accordingly, the setup
temperatures of the motor and the inverter are increased to weaken
the cooling performance. As a result, energy can be saved.
Regarding the setup temperature of the battery, the temperature
range is broadened.
[0209] The vehicle state in the eighth column of FIG. 17
corresponds to a vehicle state (before stop) where stopped vehicle
is predicted from the travel plan information such as upon the
arrival at the destination. In this case, the setup temperatures of
the motor, the inverter, and the battery are set in the same manner
as in the case of "before temporary stop". The
air-cooling/air-heating of the vehicle interior and cooling/warming
of the gearbox are stopped in advance to save energy since it is
predicted that the driving of the vehicle will be stopped soon.
Upon the stopped state as in the ninth vehicle state, the
air-cooling/air-heating of the vehicle interior and cooling/warming
of all pieces of the temperature controlling object equipment are
stopped.
[0210] It should be understood that during the air-conditioning of
the vehicle interior and cooling/warming of each of equipment, when
the temperature of each equipment is approximately in its upper
limit temperature, the cooling/warming for each equipment has a
higher priority over the air-conditioning of the vehicle
interior.
[0211] In the above-mentioned control of the flowchart shown in
FIG. 11, the temperature variation is predicted in step S3 and it
is configured to change the setup temperature (target temperature)
of the cooling medium based on the result of the prediction.
However, the vehicle state shown in FIG. 17 may be predicted from
the driving information and the travel plan information, and then
the change of the setup temperature may be determined directly from
the result of the prediction.
[0212] As mentioned above, the air-conditioning system for a
vehicle includes: a refrigeration cycle circuit 90, having a
compressor 1 that compresses a first cooling medium 40 and a first
heat exchanger 2 that exchanges heat with external air; and a
cooling/air-heating system 60 provided with circuits 91A, 91B that
circulate a second cooling medium (cooling medium 41A, 41B) to a
temperature controlling object (a motor, an inverter, a battery, a
gearbox, a vehicle interior) to perform cooing/air-heating, and a
third heat exchanger 4A, 4B, that exchanges heat between the
cooling medium 40 and the cooling medium 41A, 41B. The control
device 61 predicts a forward temperature of the temperature
controlling object based on at least one of detected temperatures
of temperature sensors 62, 63 and a driving state of the vehicle at
present, changes a target temperature of the temperature
controlling object or a target temperature of the cooling medium
41A, 41B based on the result of the prediction, and controls the
refrigeration cycle circuit 90 and the circuits 91A, 91B based on
the changed target temperature to control cooling/air-heating of
the temperature controlling object.
[0213] As shown in FIG. 17, with respect to the vehicle state that
is predicted based on the travel plan information, etc. of the
navigation device 68, the target temperature (setup temperature) of
each temperature controlling object may be changed in advance.
[0214] Instead of predicting a temperature of the temperature
controlling object, a running state may be predicted based on the
travel plan information input by the navigation device 68 provided
on the vehicle, and the target temperature of the temperature
controlling object or the target temperature of the cooling medium
41A, 41B may be changed based on the result of the prediction.
[0215] As a result, by performing air-cooling/air-heating depending
on the vehicle state, each temperature controlling object may be
maintained effectively and at the same time efficient
air-cooling/air-heating can be performed. Since the
air-cooling/air-heating is performed in advance by predicting the
vehicle state, delay in time of air-cooling/air-heating can be
avoided and at the same time abrupt increase in rotational speed of
the compressor 1, the exterior fan 3, the interior fan 8, the
circulation pump 5A, 5B can be prevented, so that the effect of
reducing noises can be expected.
[0216] For example, by using the above-mentioned vehicle speed and
accelerator pedal depressing amount as the driving state, the
temperatures of the motor and the inverter from the present time
are predicted based on the driving state and the temperatures of
the motor and the inverter, and the target temperatures of the
motor and the inverter are changed based on the predicted
temperatures. By increasing the cooling performance of the motor
and the inverter in advance as mentioned above, it is possible to
smoothly cope with an actual increase in the accelerator pedal
depressing amount and avoid an excessive increase in temperature of
the motor and the inverter due to the time lag.
[0217] As shown in FIG. 17, by changing in advance the target
temperature (setup temperature) for each temperature controlling
object with respect to the vehicle state predicted based on the
travel plan information provided by the navigation device 68, the
temperature of each temperature controlling object can be
appropriately and quickly controlled corresponding to the
situation.
[0218] When "before start running" of the vehicle is predicted from
the travel plan information, etc., by performing
air-cooling/air-heating of the vehicle interior and
cooling/air-heating of the electromotive driving equipment (for
example, cooling/warming of the battery and the gearbox) in
advance, improvement of comfortableness and efficient driving can
be achieved. In case the temperature of the electromotive driving
equipment (for example, the inverter, the motor, the battery, the
gearbox) is near at the target temperature, the cooling/warming of
the electromotive driving equipment is controlled with higher
priority over controlling the cooling/air-heating of the vehicle
interior, so that a safe and efficient running state is not
impaired by the influence of the cooling/air-heating of the vehicle
interior.
[0219] The above described embodiments are exemplary and various
modifications can be made without departing from the scope of the
invention. This is because the advantageous effect of each of the
embodiments can be exhibited alone or in any combinations thereof.
So far as the feature of the present invention is not impaired, the
present invention is not limited to the above-mentioned
embodiments.
[0220] In the above, various embodiments and variations thereof are
explained. However, the present invention should not be construed
as being limited thereto. Other embodiments conceivable within the
technical concept of the present invention are understood to be
encompassed by the scope of the present invention.
[0221] The disclosure of the following priority application is
incorporated by reference therein: Japanese Patent Application No.
2009-272307 (filed on Nov. 30, 2009).
* * * * *