U.S. patent application number 15/270919 was filed with the patent office on 2017-04-27 for power router apparatus for generating code-modulated powers.
The applicant listed for this patent is Panasonic Intellectual Property Management Co., Ltd.. Invention is credited to SHOICHI HARA, KOHEI MASUDA, TAIKI NISHIMOTO, ATSUSHI YAMAMOTO.
Application Number | 20170117913 15/270919 |
Document ID | / |
Family ID | 58562122 |
Filed Date | 2017-04-27 |
United States Patent
Application |
20170117913 |
Kind Code |
A1 |
YAMAMOTO; ATSUSHI ; et
al. |
April 27, 2017 |
POWER ROUTER APPARATUS FOR GENERATING CODE-MODULATED POWERS
Abstract
A power router apparatus includes: a power divider that divides
predetermined power into a plurality of divided powers including
first divided power and second divided power; a first code
modulator that code-modulates the first divided power with a first
modulation code to generate first code-modulated power, which is
alternating-current power; and a second code modulator that
code-modulates the second divided power with a second modulation
code to generate second code-modulated power, which is
alternating-current power.
Inventors: |
YAMAMOTO; ATSUSHI; (Kyoto,
JP) ; HARA; SHOICHI; (Tokyo, JP) ; NISHIMOTO;
TAIKI; (Osaka, JP) ; MASUDA; KOHEI; (Osaka,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Panasonic Intellectual Property Management Co., Ltd. |
Osaka |
|
JP |
|
|
Family ID: |
58562122 |
Appl. No.: |
15/270919 |
Filed: |
September 20, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H03M 1/0617 20130101;
H02M 1/00 20130101; H03M 3/00 20130101; H02M 7/5387 20130101; H02M
2001/008 20130101; Y04S 40/121 20130101; H04B 3/542 20130101 |
International
Class: |
H03M 1/06 20060101
H03M001/06; H03M 3/00 20060101 H03M003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 23, 2015 |
JP |
2015-208607 |
Claims
1. A power router apparatus comprising: a power divider that
divides predetermined power into a plurality of divided powers
including first divided power and second divided power; a first
code modulator that code-modulates the first divided power with a
first modulation code to generate first code-modulated power, which
is alternating-current power; and a second code modulator that
code-modulates the second divided power with a second modulation
code to generate second code-modulated power, which is
alternating-current power.
2. The power router apparatus according to claim 1, wherein at
least one of the first modulation code and the second modulation
code includes an orthogonal code.
3. The power router apparatus according to claim 1, wherein the
first code modulator includes a first circuit including a plurality
of first switches; and the second code modulator includes a second
circuit including a plurality of second switches.
4. The power router apparatus according to claim 1, wherein the
first code modulator includes a first H-bridge circuit in which
four first bidirectional switch circuits are connected in a
full-bridge configuration; and the second code modulator includes a
second H-bridge circuit in which four second bidirectional switch
circuits are connected in a full-bridge configuration.
5. The power router apparatus according to claim 3, wherein the
first code modulator further includes a first control circuit that
generates a plurality of first control signals that turn on or off
the first switches; the second code modulator further includes a
second control circuit that generates a plurality of second control
signals that turn on or off the second switches; the first circuit
code-modulates the first divided power, based on the first control
signals; and the second circuit code-modulates the second divided
power, based on the second control signals.
6. The power router apparatus according to claim 1, wherein the
first divided power is direct-current power or alternating-current
power, and the second divided power is direct-current power or
alternating-current power.
7. The power router apparatus according to claim 1, further
comprising: a first code demodulator that code-demodulates a third
code-modulated power, which is alternating-current power, with a
first demodulation code to generate first code-demodulated power; a
second code demodulator that code-demodulates a fourth
code-modulated power, which is alternating-current power, with a
second demodulation code to generate second code-demodulated power;
and a power combiner that combines a plurality of code-demodulated
powers including the first code-demodulated power and the second
code-demodulated power to generate combined power as the
predetermined power.
8. The power router apparatus according to claim 7, wherein at
least one of the first demodulation code and the second
demodulation code includes an orthogonal code.
9. The power router apparatus according to claim 7, wherein the
first code-demodulated power is direct-current power or
alternating-current power, and the second code-demodulated power is
direct-current power or alternating-current power.
10. The power router apparatus according to claim 1, further
comprising: a power storage device that stores at least one of the
divided powers.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to a power router apparatus
and a power transmission system having the power router
apparatus.
[0003] 2. Description of the Related Art
[0004] In recent years, installing a local, small-scale power grid
has been proposed in order to reduce losses due to long-distance
power transmission and in order to realize power self-sufficiency.
Examples of apparatuses and devices that can be connected to such a
power grid include, a direct-current (DC) power supply, an
alternating-current (AC) power supply, and loads that require
different power values.
[0005] Japanese Unexamined Patent Application Publication No.
2013-138612 discloses a multi-terminal power conversion apparatus
for asynchronously and flexibly supplying power.
[0006] Japanese Unexamined Patent Application Publication No.
2011-91954 discloses a power supply apparatus including a
communication unit that transmits/receives information signals
to/from another apparatus and a power-supply unit that supplies
power to the other apparatus.
SUMMARY
[0007] In one general aspect, the techniques disclosed here feature
a power router apparatus having: a power divider that divides
predetermined power into a plurality of divided powers including
first divided power and second divided power; a first code
modulator that code-modulates the first divided power with a first
modulation code to generate first code-modulated power; and a
second code modulator that code-modulates the second divided power
with a second modulation code to generate second code-modulated
power. The first code-modulated power is AC power, and the second
code-modulated power is AC power.
[0008] It should be noted that comprehensive or specific
embodiments may be implemented as a power transmission system, or a
power transmission method.
[0009] Additional benefits and advantages of the disclosed
embodiments will become apparent from the specification and
drawings. The benefits and/or advantages may be individually
obtained by the various embodiments and features of the
specification and drawings, which need not all be provided in order
to obtain one or more of such benefits and/or advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a block diagram illustrating an example
configuration of a power transmission system according to a first
reference mode;
[0011] FIG. 2 is a diagram illustrating one example of the waveform
of a modulated current according to the first reference mode;
[0012] FIG. 3 is a diagram illustrating an example of the waveform
of a modulated current according to a comparative example;
[0013] FIG. 4A is a graph illustrating one example of the waveform
of the generated current according to the first reference mode;
[0014] FIG. 4B is a diagram illustrating one example of the
waveform of the modulated current according to the first reference
mode;
[0015] FIG. 4C is a diagram illustrating one example of the
waveform of the demodulated current according to the first
reference mode;
[0016] FIG. 5 is a block diagram illustrating an example
configuration of a code modulator according to the first reference
mode;
[0017] FIG. 6 is a block diagram illustrating an example
configuration of a code demodulator according to the first
reference mode;
[0018] FIG. 7 is a schematic circuit diagram illustrating an
example configuration of the code modulator, a transmission path,
and the code demodulator according to the first reference mode;
[0019] FIG. 8A is a graph illustrating one example of the waveform
of a generated current according to a second reference mode;
[0020] FIG. 8B is a graph illustrating one example of the waveform
of a modulated current according to the second reference mode;
[0021] FIG. 8C is a graph illustrating one example of the waveform
of a demodulated current according to the second reference
mode;
[0022] FIG. 9 is a schematic circuit diagram illustrating an
example configuration of a code modulator according to the second
reference mode;
[0023] FIG. 10 is a schematic circuit diagram illustrating an
example configuration of a code demodulator according to the second
reference mode;
[0024] FIG. 11 is a schematic circuit diagram illustrating the
configuration of a code modulator according to a modification of
the second reference mode;
[0025] FIG. 12 is a schematic circuit diagram illustrating the
configuration of a code demodulator according to a modification of
the second reference mode;
[0026] FIG. 13 is a block diagram illustrating an example
configuration of a power transmission system according to a first
embodiment;
[0027] FIG. 14 is a block diagram illustrating an example
configuration of a power router apparatus according to the first
embodiment;
[0028] FIG. 15A is a graph illustrating the waveform of a first
input current according to a first example operation in the first
embodiment;
[0029] FIG. 15B is a graph illustrating the waveform of a second
input current according to the first example operation in the first
embodiment;
[0030] FIG. 15C is a graph illustrating the waveform of a modulated
current according to the first example operation in the first
embodiment;
[0031] FIG. 15D is a graph illustrating the waveform of a first
demodulated current according to the first example operation in the
first embodiment;
[0032] FIG. 15E is a graph illustrating the waveform of a second
demodulated current according to the first example operation in the
first embodiment;
[0033] FIG. 16A is a graph illustrating the waveform of a first
input current according to a second example operation in the first
embodiment;
[0034] FIG. 16B is a graph illustrating the waveform of a second
input current according to the second example operation in the
first embodiment;
[0035] FIG. 16C is a graph illustrating the waveform of a modulated
current according to the second example operation in the first
embodiment;
[0036] FIG. 16D is a graph illustrating the waveform of a first
demodulated current according to the second example operation in
the first embodiment;
[0037] FIG. 16E is a graph illustrating the waveform of a second
demodulated current according to the second example operation in
the first embodiment;
[0038] FIG. 17A is a graph illustrating the waveform of a
demodulated current according to a third example operation in the
first embodiment;
[0039] FIG. 17B is a graph illustrating the waveform of a converted
current according to the third example operation in the first
embodiment;
[0040] FIG. 18A is a graph illustrating the waveform of a converted
current according to a fourth example operation in the first
embodiment;
[0041] FIG. 18B is a graph illustrating the waveform of a
demodulated current according to the fourth example operation in
the first embodiment;
[0042] FIG. 19A is a graph illustrating the waveform of a first
input current according to a fifth example operation in the first
embodiment;
[0043] FIG. 19B is a graph illustrating the waveform of a second
input current according to the fifth example operation in the first
embodiment;
[0044] FIG. 19C is a graph illustrating the waveform of a modulated
current according to the fifth example operation in the first
embodiment;
[0045] FIG. 19D is a graph illustrating the waveform of a first
demodulated current according to the fifth example operation in the
first embodiment;
[0046] FIG. 19E is a graph illustrating the waveform of a second
demodulated current according to the fifth example operation in the
first embodiment;
[0047] FIG. 20A is a graph illustrating the waveform of a
demodulated current according to a sixth example operation in the
first embodiment;
[0048] FIG. 20B is a graph illustrating the waveform of a converted
current according to the sixth example operation in the first
embodiment;
[0049] FIG. 21 is a block diagram illustrating an example
configuration of a power transmission system according to a second
embodiment;
[0050] FIG. 22 is a block diagram illustrating an example
configuration of a power router apparatus according to the second
embodiment;
[0051] FIG. 23 is a block diagram illustrating an example
configuration of a power router apparatus according to a third
embodiment;
[0052] FIG. 24 is a block diagram illustrating an example
configuration of a power divider according to the third
embodiment;
[0053] FIG. 25 is a block diagram illustrating the configuration of
a power divider according to a first modification in the third
embodiment;
[0054] FIG. 26 is a block diagram illustrating the configuration of
a power divider according to a second modification in the third
embodiment;
[0055] FIG. 27 is a block diagram illustrating the configuration of
a power divider according to a third modification in the third
embodiment; and
[0056] FIG. 28 is a block diagram illustrating the configuration of
a power divider according to a fourth modification in the third
embodiment.
DETAILED DESCRIPTION
[0057] Reference modes and embodiments according to the present
disclosure will be described below with reference to the
accompanying drawings. In each embodiment described below, the same
or similar constituent elements are denoted by the same reference
numerals and/or the same name.
[0058] Various modes described below all represent comprehensive or
specific examples. Numerical values, codes, waveforms, the types of
element, the arrangement and connection of elements, signal flows,
circuit blocks, and so on described below are examples and are not
intended to limit the present disclosure. In addition, constituent
element not set forth in the independent claim that represents the
broadest concept are optional constituent elements.
First Reference Mode
[1. Power Transmission System]
[0059] FIG. 1 illustrates the configuration of a power transmission
system 100 according to a first reference mode. The power
transmission system 100 includes an electric generator 1, a code
modulator 2, a transmission path 3, a code demodulator 4, a load 5,
and a controller 10.
[0060] The electric generator 1 generates electric power (e.g., DC
power). The code modulator 2 code-modulates the generated power
with a modulation code to thereby generate code-modulated power
(i.e., a code-modulated wave). The code-modulated power is
transmitted from the code modulator 2 to the code demodulator 4
through the transmission path 3. The transmission path 3 is, for
example, a wired transmission line. The code demodulator 4
code-demodulates the code-modulated power with a demodulation code
to thereby obtain power (e.g., DC power). The obtained power is
supplied to, for example, the load 5.
[0061] The modulation code and the demodulation code are signals
including respective predetermined code sequences.
[0062] The code-modulated power is AC power. In the present
disclosure, the "AC power" refers to power whose flow direction
reverses periodically or aperiodically and whose current average
value and/or voltage average value are/is generally 0 in a
sufficiently long period of time. The current (or voltage) average
value being generally 0 means that the absolute value of the
current (or voltage) average value after the code modulation is
smaller than a predetermined value. This predetermined value is a
value obtained by, for example, dividing the maximum value of a
current (or a voltage) before the code modulation by the code
length of the modulation code. The AC power has, for example, a
waveform whose polarity changes at every predetermined period
(e.g., a period corresponding to an integer multiple of a unit
period).
[0063] The electric generator 1 has, for example, a power measuring
instrument 1m. The power measuring instrument 1m measures the
amount of electricity generated by the electric generator 1 and
transmits the measured amount of electricity generated to the
controller 10. The amount of electricity generated corresponds to,
for example, the amount of power transmitted from the electric
generator 1 to the code modulator 2. The power measuring instrument
1m may be provided at a stage prior to the code modulator 2.
[0064] The load 5 has, for example, a power measuring instrument
5m. The power measuring instrument 5m measures the amount of power
used by the load 5 and transmits the measured amount of power used
to the controller 10. The amount of power used corresponds to, for
example, the amount of power transmitted from the code demodulator
4 to the load 5. The power measuring instrument 5m may be provided
at a stage subsequent to the code demodulator 4.
[0065] Each of the electric generator 1 and the load 5 may be, for
example, a power storage device, such as a battery or a capacitor.
In this case, for example, power generated in a time segment in
which the amount of power consumption is small can be stored, and
the stored power can be effectively used. This makes it possible to
enhance the power efficiency of the entire system.
[0066] The controller 10 receives information about the measured
amounts of power and controls the code modulator 2 and the code
demodulator 4 on the basis of the corresponding amounts of power.
For example, the controller 10 transmits instruction signals to the
code modulator 2 and the code demodulator 4.
[0067] The instruction signals include a synchronization signal for
making the operation of the code modulator 2 and the operation of
the code demodulator 4 synchronize with each other. The instruction
signals transmitted to the code modulator 2 include, for example,
timing information indicating a timing at which the generated power
is to be code-modulated. The instruction signals transmitted to the
code demodulator 4 include, for example, timing information
indicating a timing at which the code-modulated power is to be
code-demodulated. This makes it possible to cause the code
modulation and the code demodulation of power to synchronize with
each other accurately.
[0068] The instruction signals transmitted to the code modulator 2
include, for example, code information regarding the modulation
code, and the instruction signals transmitted to the code
demodulator 4 include, for example, code information regarding the
demodulation code. In the present disclosure, the "code
information" may be a code sequence itself, may be designation
information for designating a specific one of a plurality of code
sequences, or may be parameter information for generating a code
sequence.
[0069] For example, the controller 10 may transmit a code sequence
of a modulation code to the code modulator 2 and may transmit a
code sequence of a demodulation code to the code demodulator 4.
[0070] For example, the controller 10 may transmit designation
information that designates a code sequence of a modulation code to
the code modulator 2, and the code modulator 2 may generate a
modulation code on the basis of the designation information. The
controller 10 may transmit designation information that designates
a code sequence of a demodulation code to the code demodulator 4,
and the code demodulator 4 may generate a demodulation code on the
basis of the designation information.
[0071] Alternatively, the modulation code may be pre-set in the
code modulator 2, and the demodulation code may be pre-set in the
code demodulator 4.
[0072] Now, suppose a case in which the power transmission system
100 includes a plurality of electric generators 1, a plurality of
code modulators 2, a plurality of code demodulators 4, and a
plurality of loads 5, by way of example. In this case, for example,
the controller 10 transmits the code information regarding the
modulation code to one code modulator 2 selected from the plurality
of code modulators 2 and transmits the code information regarding
the demodulation code to one code demodulator 4 selected from the
plurality of code demodulators 4. This allows power to be
transmitted from the electric generator 1 connected to the selected
code modulator 2 to the load 5 connected to the selected code
demodulator 4.
[0073] FIG. 1 illustrates a generated current I1, a code-modulated
current I2, and a code-demodulated current I3, instead of the
generated power, the code-modulated power, and the code-demodulated
power. Although an example in which a current is modulated and
demodulated is described below, the present disclosure is not
limited thereto, and for example, a voltage may be modulated and
demodulated. The "current" in the description below can be read
instead as a "voltage" or "power", as appropriate.
[2. Transmission Efficiency of Code-Modulated Power]
[0074] FIG. 2 illustrates an example of the waveform of the
modulated current I2. FIG. 3 illustrates an example of the waveform
of a modulated current I2a according to a comparative example. In
FIGS. 2, 1s and -1s represent values constituting a modulation
code, the values corresponding to the current values of the
modulated current I2 in corresponding periods. In FIG. 3, 1s and 0s
represent values constituting a modulation code, the values
corresponding to the current values of the modulated current I2a in
corresponding periods. A code sequence consisting of 0s and 1s
corresponds to a modulation code used in a typical communication
system.
[0075] In the example illustrated in FIG. 2, the code modulator 2
converts the generated current I1 into a modulated wave (i.e., the
modulated current I2) having "1s" and "-1s". Thus, the modulated
current I2 is AC. In this case, in each period in which the
modulated current I2 indicates "1", positive current is transmitted
from the code modulator 2 to the code demodulator 4, and in each
period in which the modulated current I2 indicates "-1" (e.g., a
period Ta in FIG. 2), negative current is transmitted from the code
modulator 2 to the code demodulator 4. Thus, power is transmitted
in all periods, thereby realizing high transmission efficiency.
[0076] In the example illustrated in FIG. 3, the modulated current
I2a has a modulated wave having "1s" and "0s" and is not AC. In
this case, in a period in which the modulated current I2a indicates
"0" (e.g., a period Tb in FIG. 3), the modulated current I2a
becomes zero, and thus no power is transmitted. Thus, when the
code-modulated power is not AC power, the power transmission
efficiency decreases.
[0077] Comparison between FIG. 2 and FIG. 3 shows that power can be
transmitted with high transmission efficiency when the
code-modulated power is AC power, particularly, when the code
sequence of the modulation code does not include "0".
[3. Code Modulation and Demodulation of DC Power]
[0078] FIGS. 4A to 4C illustrate examples of the waveforms of the
generated current I1, the modulated current I2, and the demodulated
current I3, respectively.
[0079] The generated current I1 illustrated in FIG. 4A was DC.
[0080] The modulated current I2 illustrated in FIG. 4B was obtained
by multiplying the generated current I1 by a modulation code M1. In
this example, the modulation code M1 have a code sequence given
by:
M1=[1 -1 1 1 1 -1 -1 -1 1 -1 -1 -1 1 1] (1)
[0081] The frequency of the modulation code was 35 kHz, and the
time span of each value constituting the modulation code was 14.3
(={1/(35 kHz)}/2) .mu.s. A period T illustrated in FIG. 4B
represents one cycle of the code sequence of the modulation code
M1.
[0082] The demodulated current I3 illustrated in FIG. 4C was
obtained by multiplying the modulated current I2 with a
demodulation code D1. In this example, the modulation code M1 and
the demodulation code D1 had the same code sequence. That is, the
demodulation code D1 had code sequences given by:
D1=[1 -1 1 1 1 -1 -1 -1 1 -1 -1 -1 1 1] (2)
[0083] In this case, the frequency of the demodulation code was 35
kHz, and the time span of each value constituting the demodulation
code was 14.3 .mu.s.
[0084] A result obtained by multiplying the modulated current I2 by
the demodulation code D1 corresponds to a result obtained by
multiplying the generated current I1 by M1.times.D1. In this case,
M1.times.D1 has a code sequence given by:
M1.times.D1=[1 1 1 1 1 1 1 1 1 1 1 1 1 1] (3)
[0085] Thus, as illustrated in FIG. 4C, a DC equivalent to the
generated current I1 was restored as the demodulated current I3
through the code modulation and the code demodulation.
[0086] As described above, the modulation and demodulation method
according to this reference mode makes it possible to realize
low-loss power transmission through accurate synchronization.
[0087] For example, when the modulation code M1 is repeatedly used
in the manner illustrated in FIG. 4B, power can be transmitted with
high efficiency for a long period of time.
[0088] In the above-described example, the eighth to 14th values of
the modulation code M1 respectively correspond to values obtained
by reversing the polarities of the first to seventh values of the
modulation code M1. When such modulation code is used, the average
of the modulated current I2 becomes 0, thus making it possible to
realize transmission with only AC that is free of DC components.
Thus, it is possible to transmit power with high transmission
efficiency.
[4. Code Modulator and Code Demodulator]
[0089] FIG. 5 illustrates an example configuration of the code
modulator 2.
[0090] In FIG. 5, the code modulator 2 includes a communication
circuit 21, a control circuit 25, and an H-bridge circuit 23. The
control circuit 25 includes, for example, a control integrated
circuit (IC) 20 and a gate driver 22.
[0091] The communication circuit 21 receives the instruction
signals from the controller 10 and outputs the instruction signals
to the control IC 20. The communication circuit 21 includes, for
example, an antenna, a tuner circuit, and a wave detector.
[0092] The instruction signals include, for example, a
synchronization signal and code information regarding the
modulation code. Each synchronization signal may be, for example, a
trigger signal for starting the modulation and/or may be a trigger
signal for ending the modulation. Alternatively, the
synchronization signal may be, for example, time information
indicating the time at which the modulation is to be started and/or
time information indicating the time at which the modulation is to
be ended. The trigger signals and the time information are examples
of timing information in the present disclosure.
[0093] The control IC 20 generates a modulation code on the basis
of the instruction signals and causes the gate driver 22 to
generate control signals according to the modulation code. The
control IC 20 includes a processor. The control IC 20 is, for
example, a microcomputer.
[0094] The gate driver 22 outputs the control signals to the
H-bridge circuit 23 to thereby cause the H-bridge circuit 23 to
execute a code modulation operation.
[0095] The code modulator 2 has input terminals T1 and T2 connected
to the electric generator 1 and output terminals T3 and T4
connected to the transmission path 3.
[0096] FIG. 6 illustrates an example configuration of the code
demodulator 4.
[0097] In FIG. 6, the code demodulator 4 includes a communication
circuit 31, a control circuit 35, and an H-bridge circuit 33. The
control circuit 35 includes, for example, a control IC 30 and a
gate driver 32.
[0098] The communication circuit 31 receives the instruction
signals from the controller 10 and outputs the instruction signals
to the control IC 30. The communication circuit 31 includes, for
example, an antenna, a tuner circuit, and a wave detector.
[0099] The instruction signals include, for example, a
synchronization signal and code information regarding the
demodulation code. The synchronization signal may be, for example,
a trigger signal for starting the demodulation and/or a trigger
signal for ending the demodulation. Alternatively, the
synchronization signal may be, for example, time information
indicating the time at which the demodulation is to be started
and/or time information indicating the time at which the
demodulation is to be ended. The trigger signals and the time
information are examples of the timing information in the present
disclosure.
[0100] The control IC 30 generates a demodulation code on the basis
of the instruction signals and causes the gate driver 32 to
generate control signals according to the demodulation code. The
control IC 30 includes a processor and is, for example, a
microcomputer.
[0101] The gate driver 32 outputs the control signals to the
H-bridge circuit 33 to thereby cause the H-bridge circuit 33 to
execute a code demodulation operation.
[0102] The code demodulator 4 has input terminals T11 and T12
connected to the transmission path 3 and output terminals T13 and
T14 connected to the load 5.
[0103] As illustrated in FIG. 1, the controller 10 transmits the
control signals to the code demodulator 4 and the code modulator 2
through paths different from the transmission path 3. The
controller 10, however, may transmit the control signals to the
code modulator 2 and the code demodulator 4 through the
transmission path 3. In this case, the control signals can be
transmitted, for example, through multiplexing with the
code-modulated power. For example, this reduces the number of
communication paths from the controller 10 to the code modulator 2
and the code demodulator 4, thereby making it possible to reduce
cost.
[0104] FIG. 7 illustrates an example configuration of the control
circuit 25 and the H-bridge circuit 23 in the code modulator 2 and
an example configuration of the control circuit 35 and the H-bridge
circuit 33 in the code demodulator 4.
[0105] In FIG. 7, the H-bridge circuit 23 includes four switch
circuits SS1, SS2, SS3, and SS4 connected in a full-bridge
configuration. For example, the switch circuits SS1, SS2, SS3, and
SS4 include switches S1, S2, S3, and S4, respectively.
[0106] In FIG. 7, the H-bridge circuit 33 includes four switch
circuits SS11, SS12, SS13, and SS14 connected in a full-bridge
configuration. For example, the switch circuits SS11, SS12, SS13,
and SS14 include switches S11, S12, S13, and S14, respectively.
[0107] Each of the switches S1 to S4 and S11 to S14 may be, for
example, a bidirectional switch or a metal-oxide semiconductor
(MOS) transistor.
[0108] The control circuit 25 generates predetermined code
sequences m1 and m2. The control circuit 25 outputs the code
sequence m1 to the switches S1 and S4 as control signals and
outputs the code sequence m2 to the switches S2 and S3 as control
signals.
[0109] For example, each of the switches S1 to S4 is in an ON state
when a signal indicating "1" is input thereto, and each of the
switches S1 to S4 is in an OFF state when a signal indicating "0"
is input thereto. When the switch S1 is in the ON state, current
flows from the terminal T1 to the terminal T3. When the switch S3
is in the ON state, current flows from the terminal T1 to the
terminal T4. When the switch S2 is in the ON state, current flows
from the terminal T3 to the terminal T2. When the switch S4 is in
the ON state, current flows from the terminal T4 to the terminal
T2.
[0110] The control circuit 35 generates predetermined code
sequences d1 and d2. The control circuit 35 outputs the code
sequence d1 to the switches S12 and S13 as control signals and
outputs the code sequence d2 to the switches S11 and S14 as control
signals.
[0111] For example, each of the switches S11 to S14 is in an ON
state when a signal indicating "1" is input thereto, and each of
the switches S11 to S14 is in an OFF state when a signal indicating
"0" is input thereto. When the switch S11 is in the ON state,
current flows from the terminal T12 to the terminal T13. When the
switch S13 is in the ON state, current flows from the terminal T11
to the terminal T13. When the switch S12 is in the ON state,
current flows from the terminal T14 to the terminal T12. When the
switch S14 in the ON state, current flows from the terminal T14 to
the terminal T11.
[0112] In FIG. 7, current that flows in the direction indicated by
each solid-line arrow is regarded as positive current. In FIG. 7,
the structure of the code modulator 2 and the structure of the code
demodulator 4 are generally symmetrical to each other, but the
directions in which the currents flow differ from each other.
[5. Operation]
[5-1. Control Signals]
[0113] Table 1 illustrates examples of code sequences of the
control signals m1 and m2 input to the switches S1 to S4 in the
code modulator 2 and examples of code sequences of the control
signals d1 and d2 input to the switches S11 to S14 in the code
demodulator 4.
TABLE-US-00001 TABLE 1 CONTROL SIGNAL CODE SEQUENCE m1 c1a = [1 0 1
1 1 0 0] m2 c1b = [0 1 0 0 0 1 1] d1 c1a = [1 0 1 1 1 0 0] d2 c1b =
[0 1 0 0 0 1 1]
[0114] In the examples, the code sequence of the control signals m1
and the code sequence of control signals d1 are the same code
sequence c1a, and the code sequence of the control signals m2 and
the code sequence of the control signals d2 are the same code
sequence c1b. The code sequence c1b is a sequence obtained by
inverting all bits of the code sequence c1a.
[5-2. Operation of Code Modulator]
[0115] A description will be given of the operation of the code
modulator 2.
[0116] When the control signal m1 indicates "1", and the control
signal m2 indicates "0", the switches S1 and S4 are in the ON
state, and the switches S2 and S3 in the OFF state. At this point
in time, a positive generated current I1 input to the code
modulator 2 flows in the direction indicated by the solid-line
arrow in FIG. 7, so that a positive modulated current I2 flows to
the terminals T3 and T4. That is, the generated current I1 is
code-modulated with "1".
[0117] On the other hand, when the control signal m1 indicates "0",
and the control signal m2 indicates "1", the switches S1 and S4 are
in the OFF state, and the switches S2 and S3 are in the ON state.
At this point in time, a positive generated current I1 input to the
code modulator 2 flows in the direction indicated by the
dotted-line arrow in FIG. 7, so that a negative modulated current
I2 flows to the terminals T3 and T4. That is, the generated current
I1 is code-modulated with "-1".
[0118] The series of switching operations based on the control
signals m1 and m2 illustrated in Table 1 corresponds to an
operation for code-modulating the generated current I1 with the
modulation code Ma given by:
Ma=[1 -1 1 1 1 -1 -1] (4)
[0119] Thus, the code modulator 2 code-modulates the generated
current I1 with the modulation code Ma and outputs an AC modulated
current I2 to the transmission path 3 via the terminals T3 and
T4.
[5-3. Operation of Code Demodulator]
[0120] A description will be given of the operation of the code
demodulator 4.
[0121] The control signals d1 and d2 are synchronized with the
control signals m1 and m2. Thus, when a positive modulated current
I2 is input to the code demodulator 4, the control signal d1
indicates "1", and the control signal d2 indicates "0". At this
point in time, the switches S13 and S12 are in the ON state, and
the switches S11 and S14 are in the OFF state. Thus, the positive
modulated current I2 flows in the direction indicated by the
solid-line arrow in FIG. 7, so that a positive demodulated current
I3 flows to the terminals T13 and T14. That is, the modulated
current I2 is code-demodulated with "1".
[0122] On the other hand, when a negative modulated current I2 is
input to the code demodulator 4, the control signal d1 indicates
"0", and the control signal d2 indicates "1". At this point in
time, the switches S11 and S14 are in the ON state, and the
switches S12 and S13 are in the OFF state. Thus, the negative
modulated current I2 flows in the direction indicated by the
solid-line arrow in FIG. 7, so that a positive demodulated current
I3 flows to the terminals T13 and T14. That is, the modulated
current I2 is code-demodulated with "-1".
[0123] The series of switching operations based on the control
signals d1 and d2 in Table 1 corresponds to an operation for
code-demodulating the modulated current I2 with the demodulation
code Da given by:
Da=[1 -1 1 1 1 -1 -1] (5)
[0124] Thus, the code demodulator 4 code-demodulates the modulated
current I2 with the demodulation code Da and outputs the positive
demodulated current I3 via the terminals T13 and T14.
[5-4. Other Examples of Control Signals]
[0125] Table 2 illustrates other examples of the code sequences of
the control signals m1, m2, d1, and d2.
TABLE-US-00002 TABLE 2 CONTROL SIGNAL CODE SEQUENCE m1 [c1a c1b] =
[1 0 1 1 1 0 0 0 1 0 0 0 1 1] m2 [c1b c1a] = [0 1 0 0 0 1 1 1 0 1 1
1 0 0] d1 [c1a c1b] = [1 0 1 1 1 0 0 0 1 0 0 0 1 1] d2 [c1b c1a] =
[0 1 0 0 0 1 1 1 0 1 1 1 0 0]
[0126] In each of the code sequences of the control signals m1 and
m2 illustrated in Table 1, the number of 1s is not equal to the
number of 0s. Thus, in the code sequence of the modulation code Ma,
the number of 1s and the number of -1s are not equal to each other.
In such a case, the average of the modulated current I2 does not
become 0, and the modulated current I2 is an AC including a small
amount of DC components.
[0127] On the other hand, in Table 2, the control signals m1 and d1
each have a code sequence [c1a c1b] in which the code sequence c1a
and the code sequence c1b are coupled in tandem, and the control
signals m2 and d2 each have a code sequence [c1b c1a] in which the
code sequence c1b and the code sequence c1a are coupled in tandem.
Since the code sequence c1b is a sequence in which all bits of the
code sequence c1a are inverted, as described above, the number of
1s and the number of 0s in a code sequence in which the code
sequences c1a and c1b are coupled are equal to each other. Thus,
the modulated current I2 is an AC that does not include DC
components, thus further enhancing the transmission efficiency. The
control signals m1 and m2 illustrated in Table 2 correspond to the
modulation code M1 described above, and the control signals d1 and
d2 correspond to the demodulation code D1 described above.
Second Reference Mode
[0128] A power transmission system according to a second reference
mode is substantially the same as the power transmission system 100
described above in the first reference mode, except that the
generated power is AC power. The following description will be
given of the second reference mode, particularly, points that are
different from the first reference mode.
[1. Code Modulation and Demodulation of AC Power]
[0129] FIGS. 8A to 8C illustrate examples of the waveforms of a
generated current I1, a modulated current I2, and a demodulated
current I3, respectively.
[0130] The generated current I1 illustrated in FIG. 8A was an AC
having a rectangular waveform with a frequency of 5 kHz. The
modulated current I2 illustrated in FIG. 8B was obtained by
multiplying the generated current I1 by the modulation code M1. The
modulated current I2 illustrated in FIG. 8B was an AC. The
demodulated current I3 illustrated in FIG. 8C was obtained by
multiplying the modulated current I2 by the demodulation code D1.
The modulation code M1 and the demodulation code D1 were the same
as those described in the first reference mode. As illustrated in
FIG. 8C, an AC equivalent to the generated current I1 was restored
as the demodulated current I3 through the code modulation and the
code demodulation.
[0131] Accordingly, even when the generated power is AC power, the
power can be transmitted with high transmission efficiency, as in
the case in which the generated power is DC power.
[2. Code Modulator and Code Demodulator]
[0132] FIG. 9 illustrates an example configuration of a control
circuit 25A and an H-bridge circuit 23A in the code modulator 2
according to the second reference mode. The circuit illustrated in
FIG. 9 differs from the circuit illustrated in FIG. 7 in the
following points. [0133] (1) The switch circuits SS1 to SS4
illustrated in FIG. 7 are replaced with bidirectional switch
circuits SS21 to SS24. [0134] (2) The control circuit 25
illustrated in FIG. 7 is replaced with the control circuit 25A. The
control circuit 25A outputs code sequences m1 to m4 to the H-bridge
circuit 23A as control signals.
[0135] The switch circuit SS21 includes, in addition to a switch S1
as illustrated in FIG. 7, a switch S21 connected in a direction
opposite to and in parallel with the switch S1. The switch S21 is
turned on or off in response to the control signal m3. The switch
circuit SS22 includes, in addition to a switch S2 as illustrated in
FIG. 7, a switch S22 connected in a direction opposite to and in
parallel with the switch S2. The switch S22 is turned on or off in
response to the control signal m4. The switch circuit SS23
includes, in addition to a switch S3 as illustrated in FIG. 7, a
switch S23 connected in a direction opposite to and in parallel
with the switch S3. The switch S23 is turned on or off in response
to the control signal m4. The switch circuit SS24 includes, in
addition to a switch S4 as illustrated in FIG. 7, a switch S24
connected in a direction opposite to and in parallel with the
switch S4. The switch S24 is turned on or off in response to the
control signal m3.
[0136] The switches S21 to S24 are, for example, MOS
transistors.
[0137] FIG. 10 illustrates an example configuration of a control
circuit 35A and an H-bridge circuit 33A in the code demodulator 4
according to the second reference mode. The circuit illustrated in
FIG. 10 differs from the circuit illustrated in FIG. 7 in the
following points. [0138] (1) The switch circuits SS11 to SS14
illustrated in FIG. 7 are replaced with bidirectional switch
circuits SS31 to SS34. [0139] (2) The control circuit 35
illustrated in FIG. 7 is replaced with the control circuit 35A. The
control circuit 35A outputs code sequences d1 to d4 to the H-bridge
circuit 33A as control signals.
[0140] The switch circuit SS31 includes, in addition to a switch
S11 as illustrated in FIG. 7, a switch S31 connected in a direction
opposite to and in parallel with the switch S11. The switch S31 is
turned on or off in response to the control signal m4. The switch
circuit SS32 includes, in addition to a switch S12 as illustrated
in FIG. 7, a switch S32 connected in a direction opposite to and in
parallel with the switch S12. The switch S32 is turned on or off in
response to the control signal d3. The switch circuit SS33
includes, in addition to a switch S13 as illustrated in FIG. 7, a
switch S33 connected in a direction opposite to and in parallel
with the switch S13. The switch S33 is turned on or off in response
to the control signal d3. The switch circuit SS34 includes, in
addition to a switch S14 as illustrated in FIG. 7, a switch S34
connected in a direction opposite to and in parallel with the
switch S14. The switch S34 is turned on or off in response to the
control signal d4.
[0141] The switches S31 to S34 are, for example, MOS
transistors.
[3. Operation]
[3-1. Control Signals]
[0142] Table 3 illustrates examples of the code sequences of the
control signals m1 to m4 input to the switches S1 to S4 and S21 to
S24 in the code modulator 2 and examples of the code sequences of
the control signals d1 to d4 input to the switches S11 to S14 and
S31 to S34 in the code demodulator 4.
TABLE-US-00003 TABLE 3 CONTROL SIGNAL CODE SEQUENCE m1 [c1a c0] =
[1 0 1 1 1 0 0 0 0 0 0 0 0 0] m2 [c1b c0] = [0 1 0 0 0 1 1 0 0 0 0
0 0 0] m3 [c0 c1a] = [0 0 0 0 0 0 0 1 0 1 1 1 0 0] m4 [c0 c1b] = [0
0 0 0 0 0 0 0 1 0 0 0 1 1] d1 [c1a c0] = [1 0 1 1 1 0 0 0 0 0 0 0 0
0] d2 [c1b c0] = [0 1 0 0 0 1 1 0 0 0 0 0 0 0] d3 [c0 c1a] = [0 0 0
0 0 0 0 1 0 1 1 1 0 0] d4 [c0 c1b] = [0 0 0 0 0 0 0 0 1 0 0 0 1
1]
[0143] In this example, the code sequences of the control signals
m1, m2, m3, and m4 are the same as the code sequences of the
control signals d1, d2, d3, and d4, respectively. In Table 3, the
code sequence c1b is a code sequence obtained by inverting all bits
of the code sequence c1a, and a code sequence c0 is a code sequence
in which all bits are 0s. The time span of the code sequences c1a,
c1b, and c0 match the half cycle of the AC generated current
I1.
[3-2. Operation of Code Modulator]
[0144] A description will be given of the operation of the code
modulator 2. Now, suppose a case in which the generated current I1
becomes positive in a first half cycle (i.e., a front half of one
cycle) and becomes negative in a second half cycle (i.e., a last
half of one cycle).
[3-2-1. Operation of Code Modulator in First Half Cycle]
[0145] In the first half cycle, the switches S1 to S4 are turned on
or off in accordance with the control signals m1 and m2, and the
switches S21 to S24 are maintained in the OFF state.
[0146] When the control signal m1 indicates "1", and the control
signal m2 indicates "0", the switches S1 and S4 are in the ON
state, and the switches S2 and S3 are in the OFF state. At this
point in time, a positive generated current I1 flows in the
direction indicated by arrow A1 in FIG. 9, so that a positive
modulated current I2 flows to the terminals T3 and T4. That is, the
generated current I1 is code-modulated with "1".
[0147] On the other hand, when the control signal m1 indicates "0",
and the control signal m2 indicates "1", the switches S1 and S4 are
in the OFF state, and the switches S2 and S3 are in the ON state.
At this point in time, the positive generated current I1 flows in
the direction indicated by arrow A2 in FIG. 9, so that a negative
modulated current I2 flows to the terminals T3 and T4. That is, the
generated current I1 is code-modulated with "-1".
[0148] Thus, in the first half cycle, the code modulator 2 outputs
an AC modulated current I2 to the transmission path 3 via the
terminals T3 and T4.
[3-2-2. Operation of Code Modulator in Second Half Cycle]
[0149] In the second half cycle, the switches S1 to S4 are
maintained in the OFF state, and the switches S21 to S24 are turned
on or off in accordance with the control signals m3 and m4.
[0150] When the control signal m3 indicates "1", and the control
signal m4 indicates "0", the switches S21 and S24 are in the ON
state, and the switches S22 and S24 are in the OFF state. At this
point in time, a negative generated current I1 input to the code
modulator 2 flows in the direction indicated by arrow B1 in FIG. 9,
so that a negative modulated current I2 flows to the terminals T3
and T4. That is, the generated current I1 is code-modulated with
"1".
[0151] On the other hand, when the control signal m3 indicates "0",
and the control signal m4 indicates "1", the switches S21 and S24
are in the OFF state, and the switches S22 and S23 are in the ON
state. At this point in time, a negative generated current I1 input
to the code modulator 2 flows in the direction indicated by arrow
B2 in FIG. 9, so that a positive modulated current I2 flows to the
terminals T3 and T4. That is, the generated current I1 is
code-modulated with "-1".
[0152] Accordingly, in the second half cycle, the code modulator 2
also outputs an AC modulated current I2 to the transmission path 3
via the terminals T3 and T4.
[3-2-3. Supplement]
[0153] The series of switching operations based on the control
signals m1 to m4 illustrated in Table 2 corresponds to an operation
for code modulating the generated current I1 with the modulation
code Mb given by:
Mb=[1 -1 1 1 1 -1 -1 1 -1 1 1 1 -1 -1] (6)
[0154] In the modulation code Mb, the number of 1s is larger than
the number of -1s. However, the average of the modulated current I2
can become 0. This is because the generated current I1 is positive
in the first half cycle and is negative in the second half cycle,
and a partial sequence of the modulation code Mb in the first half
cycle and a partial sequence of the modulation code Mb in the
second half cycle are the same.
[3-3. Operation of Code Demodulator]
[0155] A description will be given of the operation of the code
demodulator 4.
[3-3-1. Operation of Code Demodulator in First Half Cycle]
[0156] In the first half cycle, the switches S11 to S14 are turned
on or off in accordance with the control signals d1 and d2, and the
switches S31 to S34 are maintained in the OFF state.
[0157] When a positive modulated current I2 is input to the code
demodulator 4 in the first half cycle, the control signal d1
indicates "1", and the control signal d2 indicates "0". At this
point in time, the switches S12 and S13 are in the ON state, and
the switches S11 and S14 are in the OFF state. Thus, the positive
modulated current I2 flows in the direction indicated by arrow C1
in FIG. 10, and a positive demodulated current I3 flows to the
terminals T13 and T14. That is, the modulated current I2 is
code-demodulated with "1".
[0158] In the first half cycle, when the negative modulated current
I2 is input to the code demodulator 4, the control signal d1
indicates "0", and the control signal d2 indicates "1". At this
point in time, the switches S12 and S13 are in the OFF state, and
the switches S11 and S14 are in the ON state. Thus, a negative
modulated current I2 flows in the direction indicated by arrow C1
in FIG. 10, and a positive demodulated current I3 flows to the
terminals T13 and T14. That is, the modulated current I2 is
code-demodulated with "-1".
[0159] Thus, the code demodulator 4 outputs the positive
demodulated current I3 via the terminals T13 and T14 in the first
half cycle.
[3-3-2. Operation of Code Demodulator in Second Half Cycle]
[0160] In the second half cycle, the switches S11 to S14 are
maintained in the OFF state, and the switches S31 to S34 are turned
on or off in accordance with the control signals d3 and d4.
[0161] In the second half cycle, when a positive modulated current
I2 is input to the code demodulator 4, the control signal d3
indicates "1", and the control signal d4 indicates "0". At this
point in time, the switches S32 and S33 are in the ON state, and
the switches S31 and S34 are in the OFF state. Thus, the positive
modulated current I2 flows in the direction indicated by arrow C2
in FIG. 10, and a negative demodulated current I3 flows to the
terminals T13 and T14. That is, the modulated current I2 is
code-demodulated with "-1".
[0162] In the second half cycle, when the negative modulated
current I2 is input to the code demodulator 4, the control signal
d3 indicates "0", and the control signal d4 indicates "1". At this
point in time, the switches S32 and S33 are in the OFF state, and
the switches S31 and S34 are in the ON state. Thus, a negative
modulated current I2 flows in the direction indicated by arrow C2
in FIG. 10, and a negative demodulated current I3 flows to the
terminals T13 and T14. That is, the modulated current I2 is
code-demodulated with "1".
[0163] Accordingly, the code demodulator 4 outputs the negative
demodulated current I3 via the terminals T13 and T14 in the second
half cycle. In other words, the code demodulator 4 generates, as
the demodulated current I3, an AC that is positive in the first
half cycle and is negative in the second half cycle, and the
waveform of the AC generally matches the waveform of the generated
current I1.
[3-3-3. Supplement]
[0164] The series of switching operations based on the control
signals d1 to d4 illustrated in Table 2 corresponds to an operation
of code-demodulating the modulated current I2 with the demodulation
code Db:
Db=[1 -1 1 1 1 -1 -1 1 -1 1 1 1 -1 -1] (7)
[4. Modification of Operation]
[0165] Table 4 illustrates other examples of the code sequences of
the control signals m1 to m4 input to the switches S1 to S4 and S21
to S24 in the code modulator 2 and other examples of the code
sequences of the control signals d1 to d4 input to switches S11 to
S14 and S31 to S34 in the code demodulator 4.
TABLE-US-00004 TABLE 4 CONTROL SIGNAL CODE SEQUENCE m1 [c1a c1b] =
[1 0 1 1 1 0 0 0 1 0 0 0 1 1] m2 [c1b c1a] = [0 1 0 0 0 1 1 1 0 1 1
1 0 0] m3 [c0 c0] = [0 0 0 0 0 0 0 0 0 0 0 0 0 0] m4 [c0 c0] = [0 0
0 0 0 0 0 0 0 0 0 0 0 0] d1 [c1a c1b] = [1 0 1 1 1 0 0 0 1 0 0 0 1
1] d2 [c1b c1a] = [0 1 0 0 0 1 1 1 0 1 1 1 0 0] d3 [c0 c0] = [0 0 0
0 0 0 0 0 0 0 0 0 0 0] d4 [c0 c0] = [0 0 0 0 0 0 0 0 0 0 0 0 0
0]
[0166] The control signals m3, m4, d3, and d4 illustrated in Table
4 maintain the switches S21 to S24 and S31 to S34 in the OFF state.
Thus, the H-bridge circuit 23A illustrated in FIG. 9 and the
H-bridge circuit 33A illustrated in FIG. 10 are the substantially
the same as the H-bridge circuit 23 and the H-bridge circuit 33,
respectively, illustrated in FIG. 7.
[0167] In addition, the control signals m1, m2, d1, and d2
illustrated in Table 4 are the same as the control signals m1, m2,
d1, and d2 illustrated in Table 2. Thus, the code modulator 2 and
the code demodulator 4 in this reference mode can realize DC-power
modulation and demodulation like those described above in the first
reference mode.
[0168] Accordingly, when the control signals are modified, the code
modulator and the code demodulator according to this reference mode
can deal with both DC-power modulation and demodulation and
AC-power modulation and demodulation.
[0169] When the electric generator 1 generates DC power, it may be,
for example, a photovoltaic generator. When the electric generator
1 generates AC power, it may be, for example, an electric generator
utilizing turbine rotation. Examples of such an electric generator
include a fossil-fuel power station, a hydropower station, a wind
power generator, a nuclear power station, and a tidal power
station.
[5. Modifications of Code Modulator and Code Demodulator]
[0170] FIG. 11 illustrates a modification of an H-bridge circuit
23B in the code modulator 2 according to the second reference mode.
The H-bridge circuit 23B illustrated in FIG. 11 includes
bidirectional switch circuits SS21A to SS24A in place of the
bidirectional switch circuits SS21 to SS24 illustrated in FIG.
9.
[0171] The bidirectional switch circuit SS21A includes switches S41
and S51 and diodes Di1 and Di11. The switches S41 and S51 are
connected in series with each other. The diode Di1 is connected in
parallel with the switch S41. The diode Di11 is connected in
parallel with the switch S51. The diode Di1 passes current from a
terminal T3 to a terminal T1. The diode Di11 passes current from
the terminal T1 to the terminal T3. Since the bidirectional switch
circuits SS22A to S524A have structures that are the same as or
similar to that of the bidirectional switch circuit SS21A,
descriptions thereof are not given hereinafter.
[0172] The control circuit 25A outputs a control signal m1 to the
switches S41 and S44, outputs a control signal m2 to the switches
S42 and S43, outputs a control signal m3 to the switches S51 and
S54, and outputs a control signal m4 to the switches S52 and S53.
The control signals m1 to m4 may be, for example, the control
signals illustrated in Table 3.
[0173] FIG. 12 illustrates a modification of an H-bridge circuit
33B in the code demodulator 4 according to the second reference
mode. The H-bridge circuit 33B illustrated in FIG. 12 includes
bidirectional switch circuits SS31A to SS34A in place of the
bidirectional switch circuits SS31 to SS34 illustrated in FIG.
10.
[0174] The bidirectional switch circuit SS31A includes switches S61
and S71 and diodes Di21 and Di31. The switches S61 and S71 are
connected in series with each other. The diode Di21 is connected in
parallel with the switch S61. The diode Di31 is connected in
parallel with the switch S71. The diode Di21 passes current from a
terminal T13 to a terminal T12. The diode Di31 passes current from
the terminal T12 to the terminal T13. Since bidirectional switch
circuits SS32A to S534A have structures that are same as or similar
to that of the bidirectional switch circuit SS31A, descriptions
thereof are not given hereinafter.
[0175] The control circuit 35A outputs a control signal d1 to
switches S62 and S63, outputs a control signal d2 to the switches
S61 and S64, outputs a control signal d3 to switches S72 and S73,
and outputs a control signal d4 to the switches S71 and S74. The
control signals d1 to d4 may be, for example, those illustrated in
Table 3.
[0176] The switches S41 to S44, S51 to S54, S61 to S64, and S71 to
S74 may be, for example, MOS transistors. In this case, the diodes
Di1 to Di4, Di11 to Di14, Di21 to Di24, and Di31 to Di34 may be,
for example, body diodes of the MOS transistors. This makes it
possible to miniaturize the bidirectional switches SS21A to SS24A
and SS31A to S534A.
First Embodiment
[0177] The following description will be given of a first
embodiment, particularly, points that are different from both the
first and second reference modes.
[1. Power Transmission System]
[0178] FIG. 13 illustrates an example configuration of a power
transmission system 200 according to the first embodiment.
[0179] The power transmission system 200 illustrated in FIG. 13
includes electric generators 1a and 1b, transmission paths 3A and
3B, a power router apparatus 6, code demodulators 4a and 4b, and
loads 5a and 5b. The electric generators 1a and 1b include power
measuring instruments 1ma and 1mb, respectively. The loads 5a and
5b include power measuring instruments 5ma and 5mb,
respectively.
[0180] The power measuring instrument 1ma measures the amount of
power generated by the electric generator 1a and transmits
information about the measured amount of power to a controller 10A.
The power measuring instrument 1mb measures the amount of power
generated by the electric generator 1b and transmits information
about the measured amount of power to the controller 10A.
[0181] The power measuring instrument 5ma measures the amount of
power consumed by the load 5a and transmits information about the
measured amount of power to the controller 10A. The power measuring
instrument 5mb measures the amount of power consumed by the load 5b
and transmits information about the measured amount of power to the
controller 10A.
[0182] Based on the information about those amounts of power, the
controller 10A generates instruction signals for the power router
apparatus 6 and the code demodulators 4a and 4b. The instruction
signals include, for example, a synchronization signal for making
the operations of code modulators 43a and 43b and the operations of
the code demodulators 4a and 4b in the power router apparatus 6
synchronize each other. The instruction signals transmitted to the
power router apparatus 6 include, for example, code information
regarding a modulation code. The instruction signals transmitted to
the code demodulators 4a and 4b include, for example, code
information regarding a demodulation code. The instruction signals
transmitted to the power router apparatus 6 may further include
information regarding power division. The power division is set,
for example, through reflection of powers requested by the loads 5a
and 5b.
[0183] The power generated by the electric generator 1a and the
power generated by the electric generator 1b are transmitted to the
power router apparatus 6 through the transmission path 3A. Each
generated power is, for example, DC power or AC power.
[0184] The power router apparatus 6 code-modulates the generated
powers on the basis of the instruction signals from the controller
10A. The code-modulated powers are combined, and the combined power
is transmitted to the code demodulators 4a and 4b through the
transmission path 3B.
[0185] On the basis of the instruction signals from the controller
10A, each of the code demodulators 4a and 4b code-demodulates the
code-modulated power to generate code-demodulated power.
[0186] Each of the loads 5a and 5b receives the corresponding
code-demodulated power.
[2. Power Router Apparatus]
[0187] FIG. 14 illustrates an example configuration of the power
router apparatus 6.
[0188] In FIG. 14, the power router apparatus 6 includes a control
circuit 40, a communication circuit 41, a power divider 42, and
code modulators 43a and 43b.
[0189] The communication circuit 41 receives the instruction
signals from the controller 10A and outputs the received
instruction signals to the control circuit 40.
[0190] On the basis of the power division information in the
instruction signals, the control circuit 40 causes the power
divider 42 to set a power dividing ratio.
[0191] On the basis of the code information in the instruction
signals, the control circuit 40 generates a plurality of control
signals according to a first modulation code and outputs the
control signals to the code modulator 43a. Similarly, on the basis
of the code information in the instruction signals, the control
circuit 40 generates a plurality of control signals according to a
second modulation code and outputs the control signals to the code
modulator 43b.
[0192] The power divider 42 divides power input via a terminal T21
into first divided power and second divided power by using the set
dividing ratio, outputs the first divided power to the code
modulator 43a, and outputs the second divided power to the code
modulator 43b. The power divider 42 may have, for example, a
resistance dividing circuit. The resistance dividing circuit has,
for example, an input port and two branched output ports, that is,
first and second output ports. In this case, power can be divided
in accordance with the ratio of the value of resistance between the
input port and the first output port to the value of resistance
between the input port and the second output port. Alternatively,
when the input power is AC power, the power divider 42 may have a
transformer for power division. The transformer has, for example,
an input-side coil and two output-side coils that couple with the
input-side coil. In this case, power can be divided in accordance
with the ratio of a coefficient of coupling between the input-side
coil and the first output-side coil to a coefficient of coupling
between the input-side coil and the second output-side coil.
[0193] The code modulators 43a and 43b are driven on the basis of
the respective control signals. The code modulator 43a
code-modulates the first divided power with the first modulation
code to generate first code-modulated power. The code modulator 43b
code-modulates the second divided power with the second modulation
code to generate second code-modulated power. The first and second
code-modulated powers are combined, and the combined power is
transmitted to the transmission path 3B via a terminal T22.
[3. Operation]
[0194] A description will be given of various example operations of
the code modulators 43a and 43b in the power router apparatus 6 and
the code demodulators 4a and 4b. In the example described below,
each of the code modulators 43a and 43b has the configuration
illustrated in FIG. 9, and each of the code demodulators 4a and 4b
has the configuration illustrated in FIG. 10.
[3-1. Code Modulation and Demodulation of DC Powers]
[0195] In a first example operation, two DCs were code-modulated
into two code-modulated currents, respectively, and the two
code-modulated currents were code-demodulated into two DCs,
respectively.
[0196] In this example operation, control signals m1 to m4 input to
the code modulator 43a and control signals d1 to d4 input to the
code demodulator 4a had the code sequences illustrated in Table 4
described above. Control signals m1 to m4 input to the code
modulator 43b and control signals d1 to d4 input to the code
demodulator 4b had the code sequences illustrated in Table 5
below.
TABLE-US-00005 TABLE 5 CONTROL SIGNAL CODE SEQUENCE m1 [c2a c2b] =
[1 1 1 0 0 1 0 0 0 0 1 1 0 1] m2 [c2b c2a] = [0 0 0 1 1 0 1 1 1 1 0
0 1 0] m3 [c0 c0] = [0 0 0 0 0 0 0 0 0 0 0 0 0 0] m4 [c0 c0] = [0 0
0 0 0 0 0 0 0 0 0 0 0 0] d1 [c2a c2b] = [1 1 1 0 0 1 0 0 0 0 1 1 0
1] d2 [c2b c2a] = [0 0 0 1 1 0 1 1 1 1 0 0 1 0] d3 [c0 c0] = [0 0 0
0 0 0 0 0 0 0 0 0 0 0] d4 [c0 c0] = [0 0 0 0 0 0 0 0 0 0 0 0 0
0]
[0197] Since the operations of the code modulator 43a and the code
demodulator 4a have been described above, descriptions thereof are
not given hereinafter. Also, since operations of the code modulator
43b and the code demodulator 4b are substantially the same as those
described above except that the control signals are different,
descriptions of the operations are not given hereinafter.
[0198] As illustrated in Tables 4 and 5, the code sequence c1a and
a code sequence c2a were different from each other, and the code
sequence c1b and a code sequence c2b were different from each
other. The code sequence c1a and the code sequence c2a were
orthogonal to each other, and the code sequence c1b and the code
sequence c2b were orthogonal to each other. More specifically, the
code sequence c1a and the code sequence c2a were 7-bit orthogonal
Gold sequences different from each other, and the code sequence c1b
and the code sequence c2b were 7-bit orthogonal Gold sequences
different from each other.
[0199] FIGS. 15A, 15B, 15C, 15D, and 15E illustrate the waveforms
of an input current I11A, an input current I12A, a modulated
current I2, a demodulated current I31, and a demodulated current
I32, respectively, illustrated in FIGS. 13 and 14. In this case,
the modulated current I2 corresponds to a combined current obtained
by combining a modulated current output from the code modulator 43a
and a modulated current output from the code modulator 43b. In this
case, it was assumed that a generated current I11 and the input
current I11A were equal to each other, and a generated current I12
and the input current I12A were equal to each other.
[0200] In this example operation, a current requested by the load
5a was a DC of 100 mA, and a current requested by the load 5b was a
DC of 50 mA.
[0201] The input current I11A illustrated in FIG. 15A was a DC of
100 mA, and the input current I12A illustrated in FIG. 15B was a DC
of 50 mA. The modulated current I2 illustrated in FIG. 15C was an
AC that varies in the range of -150 mA to 150 mA. The demodulated
current I31 illustrated in FIG. 15D was a DC of 100 mA, and the
demodulated current I32 illustrated in FIG. 15E was a DC of 50
mA.
[0202] Comparison between FIG. 15A and FIG. 15D shows that the DC
I11 generated by the electric generator 1a was transmitted to the
load 5a through the code modulation and demodulation. Comparison
between FIG. 15B and FIG. 15E shows that the DC I12 generated by
the electric generator 1b was transmitted to the load 5b through
the code modulation and demodulation.
[0203] The series of switching operations in which the code
modulator 43a performed based on the control signals m1 to m4
illustrated in Table 4 corresponds to an operation for
code-modulating the input current I11A with the modulation code M1
described above. The series of switching operations in which the
code demodulator 4a performed based on the control signals d1 to d4
illustrated in Table 4 corresponds to an operation for
code-modulating the modulated current I2 with the demodulation code
D1 described above. The series of switching operations in which the
code modulator 43b performed based on the input current I12A
illustrated in Table 5 corresponds to an operation for
code-modulating the control signals m1 to m4 with the modulation
code M2 described below. The series of switching operations in
which the code demodulator 4b performed based on the control
signals d1 to d4 illustrated in Table 5 corresponds to an operation
for code-modulating the modulated current I2 with the demodulation
code D2 described below.
M2=[1 1 1 -1 -1 1 -1 -1 -1 -1 1 1 -1 1] (8)
D2=[1 1 1 -1 -1 1 -1 -1 -1 -1 1 1 -1 1] (9)
[0204] In this case, the front half of the code sequence of the
modulation code M1 and the front half of the code sequence of the
modulation code M2 are orthogonal Gold sequences that are
orthogonal to each other. The last half of the code sequence of the
modulation code M1 and the last half of the code sequence of the
modulation code M2 are orthogonal Gold sequences that are
orthogonal to each other. The front half of the code sequence of
the demodulation code D1 and the front half of the code sequence of
the demodulation code D2 are orthogonal Gold sequences that are
orthogonal to each other. The last half of the code sequence of the
demodulation code D1 and the last half of the code sequence of the
demodulation code D2 are orthogonal Gold sequences that are
orthogonal to each other.
[0205] Accordingly, results illustrated in FIGS. 15A to 15E
indicate advantages described below. [0206] (A) Since the
modulation code include the orthogonal codes, a plurality of
modulated powers can be concurrently transmitted through the same
transmission path. [0207] (B) Since the demodulation code include
the orthogonal codes, a plurality of modulated powers concurrently
transmitted through the same transmission path can be appropriately
split.
[0208] With the arrangement described above, the power transmission
system 200 allows a plurality of DC powers to be concurrently and
independently transmitted.
[3-2. Code Modulation and Demodulation of Plurality of AC
Powers]
[0209] In a second example operation, two ACs were code-modulated
into two code-modulated currents, respectively, and then the two
code-modulated currents were code-demodulated into two ACs,
respectively.
[0210] In this example operation, control signals m1 to m4 input to
the code modulator 43a and control signals d1 to d4 input to the
code demodulator 4a had the code sequences illustrated in Table 3
described above. Control signals m1 to m4 input to the code
modulator 43b and control signals d1 to d4 input to the code
demodulator 4b had code sequences illustrated in Table 6 below.
TABLE-US-00006 TABLE 6 CONTROL SIGNAL CODE SEQUENCE m1 [c2a c0] =
[1 1 1 0 0 1 0 0 0 0 0 0 0 0] m2 [c2b c0] = [0 0 0 1 1 0 1 0 0 0 0
0 0 0] m3 [c0 c2a] = [0 0 0 0 0 0 0 1 1 1 0 0 1 0] m4 [c0 c2b] = [0
0 0 0 0 0 0 0 0 0 1 1 0 1] d1 [c2a c0] = [1 1 1 0 0 1 0 0 0 0 0 0 0
0] d2 [c2b c0] = [0 0 0 1 1 0 1 0 0 0 0 0 0 0] d3 [c0 c2a] = [0 0 0
0 0 0 0 1 1 1 0 0 1 0] d4 [c0 c2b] = [0 0 0 0 0 0 0 0 0 0 1 1 0
1]
[0211] Since the operations of the code modulator 43a and the code
demodulator 4a have been described above, descriptions thereof are
not given hereinafter. Also, since operations of the code modulator
43b and the code demodulator 4b are substantially the same as those
described above except that the control signals are different,
descriptions of the operations are not given hereinafter.
[0212] FIGS. 16A, 16B, 16C, 16D, and 16E illustrate the waveforms
of an input current I11A, an input current I12A, a modulated
current I2, a demodulated current I31, and a demodulated current
I32, respectively.
[0213] Comparison between FIG. 16A and FIG. 16D shows that an AC
I11 generated by the electric generator 1a was transmitted to the
load 5a through the code modulation and demodulation. Comparison
between FIG. 16B and FIG. 16E shows that an AC I12 generated by the
electric generator 1b was transmitted to the load 5b through the
code modulation and demodulation.
[0214] With the arrangement described above, the power transmission
system 200 allows a plurality of AC powers to be concurrently and
independently transmitted.
[3-3. Code Modulation and Demodulation Involving DC-AC
Conversion]
[0215] In a third example operation, two DCs were code-modulated
into two code-modulated currents, one of the code-modulated
currents was then code-demodulated into a DC, and the other
code-modulated current was converted into a predetermined AC.
[0216] In this example operation, control signals m1 to m4 input to
the code modulator 43a and control signals d1 to d4 input to the
code demodulator 4a had the code sequences illustrated in Table 4
described above. Control signals m1 to m4 input to the code
modulator 43b had the code sequences illustrated in Table 5
described above. Control signals d1 to d4 input to the code
demodulator 4b had the code sequences illustrated in Table 6
described above.
[0217] The waveforms of an input current I11A, an input current
I12A, and a modulated current I2 were analogous to the waveforms
illustrated in FIGS. 15A, 15B, and 15C, respectively. FIG. 17A and
FIG. 17B illustrate the waveform of a demodulated current I31 and
the waveform of a converted current I32, respectively.
[0218] Comparison between FIG. 15A and FIG. 17A shows that a DC I11
generated by the electric generator 1a was transmitted to the load
5a through the code modulation and demodulation. Comparison between
FIG. 15B and FIG. 17B shows that a DC I12 generated by the electric
generator 1b was transmitted to the load 5b as the AC I32 through
the code modulation and predetermined conversion.
[0219] In this example operation, the series of switching
operations in the code demodulator 4b corresponds to an operation
for converting a modulated current, modulated with the modulation
code M2, with conversion code Dc (noted below) generated based on
the modulation code M2.
Dc=[1 1 1 -1 -1 1 -1 1 1 1 -1 -1 1 -1] (10)
[0220] The code sequence of the conversion code Dc in the first
half cycle is the same as the code sequence of the demodulation
code D2 in the first half cycle, and the code sequence of the
conversion code Dc in the second half cycle corresponds to a code
sequence obtained by inverting the polarity of each bit of the code
sequence of the demodulation code D2 in the second half cycle.
Thus, the conversion code Dc allow an operation for
code-demodulating the modulated current I2 and further inverting
the polarity thereof to be realized with a single conversion
operation. This allows the code demodulator 4b to generate the AC
I32 by using the modulated current I2.
[0221] With the arrangement described above, the power transmission
system 200 allows a plurality of DC powers to be concurrently and
independently transmitted. In addition, the transmitted modulated
power can be converted into desired AC power.
[3-4. Code Modulation and Demodulation Involving AC-DC
Conversion]
[0222] In a fourth example operation, two ACs were code-modulated
into two code-modulated currents, one of the code-modulated
currents was then converted into a predetermined DC, and the other
code-modulated current was code-demodulated.
[0223] In this example operation, control signals m1 to m4 input to
the code modulator 43a had the code sequences illustrated in Table
3 described above. Control signals d1 to d4 input to the code
demodulator 4a had the code sequences illustrated in Table 4
described above. Control signals m1 to m4 input to the code
modulator 43b and control signals d1 to d4 input to the code
demodulator 4b had the code sequences illustrated in Table 6
described above.
[0224] The waveforms of an input current I11A, an input current
I12A, and a modulated current I2 were analogous to the waveforms
illustrated in FIGS. 16A, 16B, and 16C, respectively. FIG. 18A and
FIG. 18B illustrate the waveform of a converted current I31 and the
waveform of a demodulated current I32, respectively.
[0225] Comparison between FIG. 16A and FIG. 18A shows that an AC
I11 generated by the electric generator 1a was transmitted to the
load 5a as the DC I31 through the code modulation and predetermined
conversion. Comparison between FIG. 16B and FIG. 18B shows that an
AC I12 generated by the electric generator 1b was transmitted to
the load 5b through the code modulation and demodulation.
[0226] With the arrangement described above, the power transmission
system 200 allows a plurality of AC powers to be concurrently and
independently transmitted. In addition, the transmitted modulated
power can be converted into desired DC power.
[3-5. Code Modulation and Demodulation of DC Power and AC
Power]
[0227] In a fifth example operation, DC and AC were code-modulated
into two code-modulated currents, and then the two code-modulated
currents were code-demodulated into the DC and the AC.
[0228] In this example operation, control signals m1 to m4 input to
the code modulator 43a and control signals d1 to d4 input to the
code demodulator 4a had the code sequences illustrated in Table 4
described above. Control signals m1 to m4 input to the code
modulator 43b and control signals d1 to d4 input to the code
demodulator 4b had the code sequences illustrated in Table 6
described above.
[0229] FIGS. 19A, 19B, 19C, 19D, and 19E illustrate the waveforms
of an input current I11A, an input current I12A, a modulated
current I2, a demodulated current I31, and a demodulated current
I32, respectively.
[0230] Comparison between FIG. 19A and FIG. 19D shows that a DC I11
generated by the electric generator 1a was transmitted to the load
5a through the code modulation and demodulation. Comparison between
FIG. 19B and FIG. 19E shows that an AC I12 generated by the
electric generator 1b was transmitted to the load 5b through the
code modulation and demodulation.
[0231] With the above-described operation, the power transmission
system 200 allows DC power and AC power to be concurrently and
independently transmitted.
[3-6. DC-Power and AC-power Code Modulation and Demodulation
Involving AC-DC Conversion]
[0232] In a sixth example operation, DC and AC were code-modulated
into two code-modulated currents, one of the code-modulated
currents was then code-demodulated into DC, and the other
code-modulated current was converted into a predetermined DC.
[0233] In this example operation, control signals m1 to m4 input to
the code modulator 43a and control signals d1 to d4 input to the
code demodulator 4a had the code sequences illustrated in Table 4
described above. Control signals m1 to m4 input to the code
modulator 43b had the code sequences illustrated in Table 6
described above. Control signals d1 to d4 input to the code
demodulator 4b had the code sequences illustrated in Table 5
described above.
[0234] The waveforms of an input current I11A, an input current
I12A, and a modulated current I2 were analogous to the respective
waveforms illustrated in FIGS. 19A, 19B, and 19C. FIGS. 20A and 20B
illustrate the waveforms of a demodulated current I31 and a
converted current I32, respectively.
[0235] Comparison between FIG. 19A and FIG. 20A shows that a DC I11
generated by the electric generator 1a was transmitted to the load
5a through the code modulation and demodulation. Comparison between
FIG. 19B and FIG. 20B shows that an AC I11 generated by the
electric generator 1a was transmitted to the load 5b as the DC I32
through the code modulation and the predetermined conversion.
[0236] With the above-described operation, the power transmission
system 200 allows DC power and AC power to be concurrently and
independently transmitted. In addition, the transmitted modulated
power can be converted into desired DC power.
[3-7. Supplement]
[0237] In the various example operations described above, the time
average of the modulated current I2 was 0. That is, the modulated
current I2 was an AC that does not include DC components. Thus,
power transmission can be realized with high transmission
efficiency.
[0238] Since a plurality of powers are transmitted through the same
transmission path 3B, the transmission path 3B can be simplified.
For example, when the transmission path 3B is a cable, it is
possible to reduce the number of cables.
[0239] Since a plurality of modulated powers are combined, and the
resulting modulated power is concurrently transmitted, for example,
the transmission time can be reduced compared with a scheme in
which powers in a plurality of channels are transmitted in a
time-division manner. In addition, according to the code modulation
and demodulation scheme, since each power is transmitted
independently, the power transmission can be performed without
affecting transmission of the other power.
[0240] Each of the code modulators 43a and 43b can execute code
modulation by using arbitrary modulation code. Similarly, each of
the code demodulators 4a and 4b can execute code demodulation by
using arbitrary demodulation code. Alternatively, each of the code
demodulators 4a and 4b can execute predetermined conversion by
using arbitrary conversion code based on modulation code.
Accordingly, pairing between the code modulator and the code
demodulator can be flexibly changed in accordance with an arbitrary
combination of a modulation code and a demodulation code. For
example, in FIG. 13, power transmission from the electric generator
1 a to the load 5b and power transmission from the electric
generator 1b to the load 5a may be executed concurrently. Even when
the number of pairing patterns increases, an increase in the size
of the circuit scale may be suppressed. Accordingly, it is possible
to realize power transmission with an apparatus having a reduced
size.
Second Embodiment
[1. Power Transmission System]
[0241] FIG. 21 illustrates an example configuration of a power
transmission system 300 according to a second embodiment. FIG. 22
illustrates an example configuration of a power router apparatus 6A
illustrated in FIG. 21. The power transmission system 300 in FIG.
21 differs from the power transmission system 200 in FIG. 13 in the
following points. [0242] (1) The power transmission system 300
includes code modulators 2a and 2b connected to respective electric
generators 1a and 1b. [0243] (2) The transmission path 3A through
which generated power is transmitted is replaced with a
transmission path 3C through which code-modulated power is
transmitted. [0244] (3) The power router apparatus 6 is replaced
with the power router apparatus 6A. The power router apparatus 6A
further includes code demodulators 44a and 44b and a power combiner
45. [0245] (4) The controller 10A is replaced with a controller
10B. The controller 10B controls the operations of the code
modulators 2a and 2b, the power router apparatus 6A, and code
demodulators 4a and 4b.
[0246] That is, in FIG. 21, the power transmission system 300
includes the electric generators 1a and 1b, the code modulators 2a
and 2b, the transmission path 3C, the power router apparatus 6A, a
transmission path 3B, the code demodulators 4a and 4b, and loads 5a
and 5b. The electric generators 1a and 1b have the power measuring
instruments 1ma and 1mb, respectively. The loads 5a and 5b have
power measuring instruments 5ma and 5mb, respectively.
[0247] The power measuring instrument 5ma measures the amount of
power consumed by the load 5a and sends information about the
measured amount of power to the controller 10B. The power measuring
instrument 5mb measures the amount of power consumed by the load 5b
and sends information about the measured amount of power to the
controller 10B.
[0248] On the basis of information about those amounts of power,
the controller 10B generates instruction signals for the code
modulators 2a and 2b, the power router apparatus 6A, and the code
demodulators 4a and 4b. The instruction signals include, for
example, a synchronization signal for making the operations of the
code modulators 2a and 2b and the operations of the code
demodulators 44a and 44b in the power router apparatus 6A
synchronize with each other and a synchronization signal for making
the operations of the code modulators 43a and 43b in the power
router apparatus 6 and the operations of the code demodulators 4a
and 4b synchronize with each other. For example, the instruction
signals transmitted to the code modulators 2a and 2b include code
information regarding a modulation code, and the instruction
signals transmitted to the power router apparatus 6A include code
information regarding a demodulation code. For example, the
instruction signals transmitted to the power router apparatus 6A
further include code information regarding a modulation code, and
the instruction signals transmitted to the code demodulators 4a and
4b include code information regarding a demodulation code. The
instruction signals transmitted to the power router apparatus 6A
may further include information regarding power division. The power
division is set, for example, through reflection of powers
requested by the loads 5a and 5b.
[0249] Powers generated by the electric generators 1a and 1b are
input to the code modulators 2a and 2b, respectively. The code
modulators 2a and 2b code-modulate the respective input powers on
the basis of the instruction signals from the controller 10B. Two
code-modulated powers are combined, and the resulting
code-modulated power is transmitted to the power router apparatus
6A through the transmission path 3C.
[0250] On the basis of the instruction signals from the controller
10B, the power router apparatus 6A (a) code-demodulates the
combined code-modulated power into a plurality of code-demodulated
powers, (b) combines the code-demodulated powers into combined
power, (c) divides the combined power into a plurality of divided
powers, and (d) code-modulates the individual divided powers into
code-modulated powers. The code-modulated powers are combined, and
the combined code-modulated power is transmitted to the code
demodulators 4a and 4b through the transmission path 3B.
[0251] On the basis of the instruction signals from the controller
10B, the code demodulators 4a and 4b code-demodulate the
corresponding code-modulated powers to generate code-demodulated
powers, respectively.
[0252] The loads 5a and 5b receive the corresponding
code-demodulated powers.
[2. Power Router Apparatus]
[0253] In FIG. 22, the power router apparatus 6A includes a control
circuit 40A, the communication circuit 41, the code demodulators
44a and 44b, the power combiner 45, the power divider 42, and the
code modulators 43a and 43b. The code demodulators 44a and 44b have
power measuring instruments 44ma and 44mb, respectively.
[0254] The code demodulator 44a is paired with the code modulator
2a, and the code demodulator 44b is paired with the code modulator
2b. The code modulator 43a is paired with the code demodulator 4a,
and the code modulator 43b is paired with the code demodulator
4b.
[0255] The communication circuit 41 receives the instruction
signals from the controller 10B and outputs the instruction signals
to the control circuit 40A.
[0256] The control circuit 40A generates a plurality of control
signals according to a first demodulation code on the basis of code
information in the instruction signals and outputs the control
signals to the code demodulator 44a. Similarly, the control circuit
40A generates a plurality of control signals according to a second
demodulation code on the basis of the code information in the
instruction signals and outputs the control signals to the code
demodulator 44b.
[0257] On the basis of the power division information in the
instruction signals, the control circuit 40A causes the power
divider 42 to set a power dividing ratio.
[0258] On the basis of the code information in the instruction
signals, the control circuit 40A generates a plurality of control
signals according to a first modulation code and outputs the
control signals to the code modulator 43a. Similarly, on the basis
of the code information in the instruction signals, the control
circuit 40A generates a plurality of control signals according to a
second modulation code and outputs the control signals to the code
modulator 43b.
[0259] The power measuring instruments 44ma and 44mb measure the
respective amounts of power generated by the code demodulators 44a
and 44b and transmit information about the amounts of power to the
control circuit 40A. The control circuit 40A transmits the
information to the controller 10B via the communication circuit
41.
[0260] The code demodulator 44a code-demodulates the code-modulated
power, input via a terminal T31, with the first demodulation code
to generate first code-demodulated power. The code demodulator 44b
code-demodulates the code-modulated power with the second
demodulation code to generate second code-demodulated power. The
first and second code-demodulated powers are output to the power
combiner 45.
[0261] The power combiner 45 combines the first and second
code-demodulated powers to generate combined power. The combined
power is output to the power divider 42. The power divider 42 may
have, for example, a resistance dividing circuit or a transformer
for division.
[0262] The power divider 42 divides the combined power into first
divided power and second divided power at a set dividing ratio. The
first and second divided powers are output to the code modulators
43a and 43b, respectively.
[0263] The code modulator 43a code-modulates the first divided
power with the first modulation code to generate first
code-modulated power. The code modulator 43b code-modulates the
second divided power with the second modulation code to generate
second code-modulated power. The first and second code-modulated
powers are combined, and the combined code-modulated power is
output to the transmission path 3B via a terminal T32.
[0264] The power transmission system 300 executes the code
modulation and demodulation twice. The code modulation operation
performed by the code modulators 43a and 43b and the code
demodulation operation performed by the code demodulators 4a and 4b
are substantially the same as those described in, for example, the
first embodiment, and thus descriptions thereof are not given
hereinafter. Also, the code modulation operation performed by the
code modulators 2a and 2b and the code demodulation operation
performed by the code demodulators 44a and 44b are substantially
the same as the code modulation operation performed by the code
modulators 43a and 43b and the code demodulation operation
performed by the code demodulators 4a and 4b, except that the
control signals are different, and thus descriptions thereof are
given hereinafter.
[0265] In the power transmission system 200, power can be
transmitted from the electric generators 1a and 1b to the loads 5a
and 5b with high efficiency and flexibly in accordance with the
type of power.
[0266] In addition, since the power router apparatus 6A has the
code demodulators 44a and 44b, the amounts of power transmitted
from the electric generators 1a and 1b can be independently and
accurately determined in the power router apparatus 6A. Thus,
information about the amount of power of each electric generator
may be utilized for, for example, buying and selling power.
Third Embodiment
[1. Power Router Apparatus]
[0267] FIG. 23 illustrates an example configuration of a power
router apparatus 6B in a power transmission system according to a
third embodiment. The power router apparatus 6B in FIG. 23 differs
from the power router apparatus 6A in FIG. 22 in the following
points. [0268] (1) The power router apparatus 6B includes a power
storage device 46. The power storage device 46 includes, for
example, a battery and/or a capacitor. [0269] (2) The power divider
42 is replaced with a power divider 42A. The power divider 42A
divides power for code modulators 43a and 43b and the power storage
device 46. [0270] (3) The control circuit 40A is replaced with a
control circuit 40B. The control circuit 40B controls code
demodulators 44a and 44b, a power combiner 45, the power divider
42A, the power storage device 46, and the code modulators 43a and
43b.
[2. Power Divider]
[0271] FIG. 24 illustrates an example configuration of the power
divider 42A. In FIG. 24, the power divider 42A includes a power
dividing circuit 51, switches SW1 to SW4, and terminals T41 to
T47.
[0272] The terminal T41 is connected to the power combiner 45, the
terminal T42 is connected to the code modulator 43a, and the
terminal T43 is connected to the code modulator 43b. The terminals
T44 to T47 are connected to the power storage device 46.
[0273] A control signal ST51 specifying a power dividing ratio is
input to the power dividing circuit 51 from the control circuit
40B. On the basis of the specified dividing ratio, the power
dividing circuit 51 divides the power input via the terminal T41
into first divided power and second divided power. The power
dividing circuit 51 may have, for example, a resistance dividing
circuit or a transformer for division.
[0274] Switching control signals ST1 to ST4 from the control
circuit 40B are input to the switches SW1 to SW4, respectively.
[0275] When the switches SW1 and SW2 are connected to respective
contact points a, the first divided power is output to the code
modulator 43a via the switches SW1 and SW2 and the terminal T42. As
a result, the first divided power is supplied to the load 5a
without being supplied to the power storage device 46.
[0276] When the switch SW1 is connected to a corresponding contact
point b, and the switch SW2 is connected to the corresponding
contact point a, the first divided power is output to the power
storage device 46 via the switch SW1 and the terminal T44. As a
result, the first divided power is stored in the power storage
device 46 and is supplied to the load 5a.
[0277] When the switch SW1 is connected to the corresponding
contact point b, and the switch SW2 is connected to a corresponding
contact point b, the first divided power is output to the power
storage device 46 via the switch SW1 and the terminal T44 and is
then output to the code modulator 43a via the terminal T46, the
switch SW2, and the terminal T42. As a result, when the first
divided power is larger than the power consumed by the load 5a,
some of the first divided power is stored in the power storage
device 46, and the remainder is supplied to the load 5a.
Conversely, when the first divided power is smaller than the power
consumed by the load 5a, the first divided power and power
discharged from the power storage device 46 are supplied to the
load 5a.
[0278] When the switches SW3 and SW4 are connected to respective
contact points a, the second divided power is output to the code
modulator 43b via the switches SW3 and SW4 and the terminal T43. As
a result, the second divided power is supplied to the load 5b
without being supplied to the power storage device 46.
[0279] When the switch SW3 is connected to a corresponding contact
point b, and the switch SW4 is connected to the corresponding
contact point a, the second divided power is output to the power
storage device 46 via the switch SW3 and the terminal T45. As a
result, the second divided power is stored in the power storage
device 46 and is not supplied to the load 5b.
[0280] When the switch SW3 is connected to the corresponding
contact point b, and the switch SW4 is connected to a corresponding
contact point b, the second divided power is output to the power
storage device 46 via the switch SW3 and the terminal T45 and is
then output to the code modulator 43b via the terminal T47, the
switch SW4, and the terminal T43. As a result, when the second
divided power is larger than the power consumed by the load 5b,
some of the second divided power is stored in the power storage
device 46, and the remainder is supplied to the load 5b.
Conversely, when the second divided power is smaller than the power
consumed by the load 5b, the second divided power and power
discharged from the power storage device 46 are supplied to the
load 5b.
[0281] When the total of powers generated by the electric
generators 1a and 1b is larger than the total of powers consumed by
the loads 5a and 5b, excessive power can be stored in the power
storage device 46 in the power router apparatus 6B. Conversely,
when the total of powers generated by the electric generators 1a
and 1b is smaller than the total of powers consumed by the loads 5a
and 5b, a shortage in power can be compensated for by discharged
power from the power storage device 46 in the power router
apparatus 6B. As a result, the power router apparatus 6B can
efficiently and reliably utilize power.
[3. Modifications of Power Divider]
[3-1. First Modification]
[0282] FIG. 25 illustrates the configuration of a power divider 42B
according to a first modification. The power divider 42B in FIG. 25
differs from the power divider 42A in FIG. 24 in that the terminals
T44 and T45 are replaced with a power combining circuit 52 and a
terminal T48.
[0283] The power combining circuit 52 is connected to a contact
point b of a switch SW1 and to a contact point b of a switch SW3.
The power combining circuit 52 combines powers input from the
switches SW1 and SW3 and outputs the combined power to a power
storage device 46 via the terminal T48. The power combining circuit
52 may have, for example, a resistance combiner. The resistance
combiner has, for example, two branched input ports, that is, first
and second input ports, and one output port. In this case, powers
can be combined in accordance with the ratio of the value of
resistance across the first input port and the output port to the
value of resistance across the second input port and the output
port. Alternatively, when the input power is AC power, the power
combining circuit 52 may have a transformer for combination. The
transformer has, for example, two input-side coils, that is, first
and second input-side coils, and an output-side coil that couples
with the input-side coils. In this case, powers can be combined in
accordance with the ratio of a coefficient of coupling between the
first input-side coil and the output-side coil to a coefficient of
coupling between the second input-side coil and the output-side
coil.
[0284] In the case of DC and AC, the power combination can be
implemented by a resistance combiner that combines powers in
accordance with the ratio of resistance across branched ports.
Also, in the case of AC, the power combination can be implemented
by, for example, a transformer combiner for combining powers in
accordance with the ratio of coupling between an input-side coil
and an output-side coil by using a transformer.
[3-2. Second Modification]
[0285] FIG. 26 illustrates the configuration of a power divider 42C
according to a second modification. The power divider 42C in FIG.
26 differs from the power divider 42B in FIG. 25 in that the power
combining circuit 52 is replaced with a power combining circuit
52A.
[0286] In FIG. 26, a power dividing circuit 51 divides power input
from a terminal T41 into three powers and outputs one of the powers
to the power combining circuit 52A. The power combining circuit 52A
combines the power from the power dividing circuit 51, power from a
switch SW1, and power from a switch SW3 and outputs combined power
to a power storage device 46 via a terminal T48.
[3-3. Third Modification]
[0287] FIG. 27 illustrates the configuration of a power divider 42D
according to a third modification. The power divider 42D in FIG. 27
includes switches SW5 and SW6, a power dividing circuit 53, and
terminal T48 and T49. A control signal ST53 that specifies a power
dividing ratio is input to the power dividing circuit 53 from the
control circuit 40B. Switching control signals ST5 and ST6 from the
control circuit 40B are input to the switches SW5 to SW6,
respectively.
[0288] When the switches SW5 and SW6 are connected to respective
contact points a, power input to a terminal T41 is input to the
power dividing circuit 53 via the switches SW5 and SW6, and the
power dividing circuit 53 divides the input power into first
divided power and second divided power. The first divided power is
output to the code modulator 43a via a terminal T42, and the second
divided power is output to a code modulator 43b via a terminal T43.
As a result, the input power is supplied to the loads 5a and 5b
without being supplied to the power storage device 46.
[0289] When the switch SW5 is connected to a corresponding contact
point b, and the switch SW6 is connected to the corresponding
contact point a, power input to the terminal T41 is output to the
power storage device 46 via the switch SW5 and the terminal T48. As
a result, the input power is stored in the power storage device 46
and is not supplied to the loads 5a and 5b.
[0290] When the switch SW5 is connected to the corresponding
contact point b, and the switch SW6 is connected to a corresponding
contact point b, power input to the terminal T41 is output to the
power storage device 46 via the switch SW5 and the terminal T48 and
is then input to the power dividing circuit 53 via a terminal T49
and the switch SW6, and the power dividing circuit 53 divides the
input power into first divided power and second divided power. The
first divided power is output to the code modulator 43a via the
terminal T42, and the second divided power is output to the code
modulator 43b via the terminal T43. As a result, when the total of
powers generated by the electric generators 1a and 1b is larger
than the total of powers consumed by the loads 5a and 5b, some of
the generated power is stored in the power storage device 46, and
the remainder is supplied to the loads 5a and 5b. Conversely, when
the total of the generated powers is smaller than the total of the
powers consumed, the generated power and power discharged from the
power storage device 46 are supplied to the loads 5a and 5b.
[3-4. Fourth Modification]
[0291] FIG. 28 illustrates the configuration of a power divider 42E
according to a fourth modification. The power divider 42E in FIG.
28 has a configuration in which the power divider 42C in FIG. 26 is
provided at a stage subsequent to the power divider 42D in FIG. 27.
The power divider 42E in FIG. 28 includes a power combining circuit
52B in place of the power combining circuit 52A.
[0292] An output terminal of the switch SW6 is connected to an
input terminal of the power dividing circuit 51.
[0293] The power combining circuit 52B combines power from the
switch SW5, power from the power dividing circuit 51, power from
the switch SW1, and power from the switch SW3 and outputs combined
power to the power storage device 46 via the terminal T48.
Other Embodiments
[0294] The present disclosure is not limited to the specific
examples described above in the reference modes and the
embodiments. The disclosed technology is not limited to the
specific examples and also encompasses any modes obtained by
performing a change, replacement, addition, omission, and so on to
the above-described modes. The present disclosure further
encompasses a combination of the embodiments and/or the reference
modes.
[0295] Although, in the first to third embodiments described above,
the power transmission system has two electric generators and two
loads, the number of electric generators and the number of loads
are not limited thereto. For example, the power transmission system
may have one electric generator and two or more loads or may have
three or more electric generators and three or more loads.
[0296] Although, in the first and second reference modes and the
first embodiment, the code sequence of the control signals, the
code sequence of the modulation code, and the code sequence of the
demodulation code each include one or more orthogonal Gold
sequences, the present disclosure is not limited thereto. For
example, the modulation code and the demodulation code may include
other orthogonal codes. Examples of the other orthogonal codes
include an m sequence.
[0297] Although, in the first and second reference modes and the
first embodiment, each code length of the control signals, the
modulation codes, and the demodulation codes is 7 bits or 14 bits,
the present disclosure is not limited thereto. The larger the code
length, the larger the number of orthogonal codes that can be
generated. Also, when the code length is increased, correlation
between the codes decreases to thereby make it possible to more
accurately divide power.
[0298] Although, in the first embodiment, the code modulator and
the code demodulator have been described as being the respective
circuits illustrated in FIGS. 9 and 10, they may be implemented by,
for example, the circuit illustrated in FIG. 7. In such a case, the
circuit configuration of the code modulator and the code
demodulator is simplified, thereby making it possible to realize a
reduction in cost and a reduction in the size of the apparatus.
[0299] Although an example in which the current is code-modulated
and code-demodulated has been described in the first and second
reference modes and the first embodiment, the voltage may be
code-modulated and code-demodulated or the current and the voltage
may be modulated and demodulated.
[0300] Although an example in which the generated current and the
input current are equal to each other has been described in the
first embodiment, the present disclosure is not limited
thereto.
[0301] Although an example in which the bidirectional switch
circuit includes two switches has been described in the second
reference mode, the bidirectional switch circuit may be implemented
by, for example, a single bidirectional switch.
[0302] In the first and second embodiments, the controller and the
control circuit in the power router apparatus may be shared. For
example, in the power transmission system, the controller may be
omitted, and the communication circuit in the power router
apparatus may be omitted. In such a case, the control circuit in
the power router apparatus can execute the operation of the
controller described above in each embodiment. This makes it
possible to reduce the size of the system, simplify the system and
reduce cost.
Overview of Embodiments
[0303] a power router apparatus according to one aspect of the
present disclosure includes: a power divider that divides
predetermined power into a plurality of divided powers including
first divided power and second divided power; a first code
modulator that code-modulates the first divided power with a first
modulation code to generate first code-modulated power; and a
second code modulator that code-modulates the second divided power
with a second modulation code to generate second code-modulated
power. The first code-modulated power is AC power, and the second
code-modulated power is AC power.
[0304] For example, at least one of the first modulation code and
the second modulation code may include an orthogonal code.
[0305] For example, the first code modulator may include a first
circuit having a plurality of first switches; and the first code
modulator may include a second circuit having a plurality of second
switches.
[0306] For example, the first code modulator may include a first
H-bridge circuit in which four first bidirectional switch circuits
are connected in a full-bridge configuration; and the second code
modulator may include a second H-bridge circuit in which four
second bidirectional switch circuits are connected in a full-bridge
configuration.
[0307] For example, the first code modulator may further include a
first control circuit that generates a plurality of first control
signals that turn on or off the first switches; and the second code
modulator may further include a second control circuit that
generates a plurality of second control signals that turn on or off
the second switches. The first circuit may code-modulate the first
divided power, based on the first control signals; and the second
circuit may code-modulate the second divided power, based on the
second control signals.
[0308] For example, the first divided power may be DC power or AC
power, and the second divided power may be DC power or AC
power.
[0309] For example, the power router apparatus may further include:
a first code demodulator that code-demodulates a third
code-modulated power with a first demodulation code to generate
first code-demodulated power; a second code demodulator that
code-demodulates a fourth code-modulated power with a second
demodulation code to generate second code-demodulated power; and a
power combiner that combines a plurality of code-demodulated powers
including the first code-demodulated power and the second
code-demodulated power to generate combined power. The
predetermined power is the combined power, and the third
code-modulated power is AC power, and the fourth code-modulated
power is AC power.
[0310] For example, at least one of the first demodulation code and
the second demodulation code may include an orthogonal code.
[0311] For example, the first code-demodulated power may be DC
power or AC power, and the second code-demodulated power may be DC
power or AC power.
[0312] For example, the power router apparatus may further include
a power storage device that stores at least one of the divided
powers.
[0313] A power transmission system according to one aspect of the
present disclosure includes the power router apparatus.
[0314] In the power transmission system according to the present
disclosure, for example, power can be transmitted from an electric
generator, such as a photovoltaic generator, a wind power
generator, or a hydroelectric power generator to a train, an
electric vehicle (EV), or the like.
* * * * *