DC power distribution system and control power generation device

Abstract

Voltage command values are set in accordance with the voltage variations of a plurality of power supply sources (1, 2, 3), and one of the outputs of a plurality of power supply circuits (21, 22, 23, 24) that output DC voltages converted in accordance with the voltage command values is supplied to a power conversion circuit (10) as a control power supply. This enables system operation to continue even at an abnormal time due to a device failure and a power outage and enables the power consumption of the control power supply to be suppressed with respect to the voltage variations of the power supply sources (1, 2, 3).

Description

Technical Field

[0001] This application relates to a DC power distribution system and a control power generation device.

Background Art

[0002] Conventionally, a DC / DC converter has been adopted as a control power source for a voltage source inverter, and its input power source can be supplied from both an AC power source and the DC voltage of the inverter or an external DC power source.

[0003] For example, the power supply circuit shown in Patent Document 1 is configured such that a capacitor is separately provided for the DC / DC converter input, and the capacitor can be charged either from an AC power source via a relay contact and a rectifier or from the DC voltage of the inverter, so that the DC voltage detection of the inverter is realized. That is, during inverter operation, it is charged from the DC voltage of the inverter, and during inverter stop, it is charged from the AC power source.

[0004] In the power system shown in Patent Document 2, power is exchanged between an electric vehicle and a power grid, and there are a charge / discharge circuit, a bidirectional inverter circuit, and their control circuits between the power grid and the vehicle battery. By selecting a voltage based on the DC voltage supplied from the DC power source of the vehicle as the operating voltage of the control circuit, power consumption is suppressed and a stable voltage is generated.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the means for generating the voltage of the control circuit, it is known that a power supply circuit such as a DC / DC converter can suppress power consumption by performing power conversion with a small voltage difference between input and output. However, in the device described in Patent Document 1, the capacitor for the DC / DC converter is configured to be charged preferentially with the higher DC voltage. Therefore, during inverter operation, power is always supplied from the DC voltage of the main circuit to the control circuit, resulting in power loss and deteriorating the efficiency of the entire system. In addition, there is a problem that the control power supply is lost during an AC power outage.

[0007] Also, in the device described in Patent Document 2, when power is supplied from the power grid or the power generation system, the operating voltage of the control circuit is always selected from the power supply circuit connected to those power sources. Therefore, the conditions for generating the operating voltage of the control circuit based on the DC voltage supplied from the DC power source in the electric vehicle are limited, and there is a problem that the effect of suppressing power consumption cannot be sufficiently obtained.

[0008] The present application has been made to solve the above problems. By setting the voltage value according to the voltage fluctuation of the power supply source, the control power supply of the system is generated from any of a plurality of power supply sources, so that the system can continue to operate even in the event of equipment failure or power outage, and a DC power distribution system and a control power supply generation device that suppress the power consumption of the control power supply against the voltage fluctuation of the power supply source are provided.

Means for Solving the Problems

[0009] The DC power distribution system disclosed in the present application forms a power distribution network that supplies power from a plurality of power supply sources to a plurality of electrical loads, and includes a power conversion circuit connected between the plurality of power supply sources and the plurality of electrical loads for supplying power according to the electrical loads, and a control power supply generation unit for supplying a control power supply for controlling the power conversion circuit. The control power supply generation unit inputs the detected voltage of each power supply source, and when the input detected voltage is greater than a predetermined value, sets a voltage command value according to the detected voltage. It has a control device, a plurality of power supply circuits connected to each power supply source for outputting a DC voltage converted according to the voltage command value, and a control power supply circuit for supplying a control power supply based on one of the outputs of the plurality of power supply circuits to the power conversion circuit. The control device is characterized in that the voltage command value corresponding to the lowest voltage among the detected voltages greater than the predetermined value is set to the maximum value.

Effect of the Invention

[0010] According to the DC power distribution system disclosed in the present application, by setting a voltage command value according to the voltage fluctuations of a plurality of power supply sources and supplying one of the outputs of a plurality of power supply circuits that output a DC voltage converted according to the voltage command value as a control power supply to the power conversion circuit, the system can continue to operate even in case of abnormalities due to equipment failures and power outages, and the power consumption of the control power supply can be suppressed against the voltage fluctuations of the power supply sources.

Brief Description of the Drawings

[0011]

Figure 1

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, preferred embodiments of the DC power distribution system according to the present application will be described with reference to the drawings. Note that the same reference numerals are assigned to the same content and corresponding parts, and detailed descriptions thereof are omitted. Similarly, in the following embodiments, duplicate descriptions of the configurations with the same reference numerals are omitted.

[0013] Embodiment 1. FIG. 1 is an overall configuration diagram of a DC power distribution system according to Embodiment 1. The DC power distribution system includes a plurality of power supply sources such as a utility power source 1, a solar cell 2, and a storage battery 3, a power conversion device 10 connected between the plurality of power supply sources and a plurality of electrical loads 4 to 6, and a control power generation unit 20 that supplies a control power source to the power conversion device 10. In the case of this embodiment, for example, the power conversion device 10 is connected between the utility power source 1 and a DC bus circuit 17, and includes a bidirectional AC / DC converter circuit 11 that performs bidirectional conversion between AC power and DC power, a DC / DC converter circuit 12 connected between the solar cell 2 and the DC bus circuit 17 among the plurality of power sources and that converts DC power, a charge / discharge circuit 13 connected between the storage battery 3 and the DC bus circuit 17 among the plurality of power sources and that charges and discharges the storage battery 3, and DC / DC converter circuits 14 to 16 connected between the DC bus circuit 17 and the plurality of electrical loads 4 to 6 and that convert the DC power of the DC bus circuit 17. FIG. 2 specifically shows an overview of each DC / DC converter circuit of the power conversion device 10. The connection between the control power generation unit 20 and the power conversion device 10 is omitted. Note that the circuit configuration of the power conversion device 10 is the same as that in FIG. 2 also in Embodiments 2 and 3.

[0014] In FIG. 1, the control power generation unit 20 receives as inputs the voltage Vac obtained from the utility power source 1, the voltage Vpv obtained from the solar cell 2, the voltage Vbat obtained from the storage battery 3, and the voltage Vbus obtained from the DC bus circuit 17, and includes power supply circuits 21 to 24 that convert each input voltage into a desired DC voltage according to a voltage command value calculated by a control device 30. Each output of the power supply circuits 21 to 24 is butted against a diode and then input to a control power supply circuit 25 that outputs a control power source Vdc.

[0015] FIG. 3 is a functional block diagram of the control device 30 in FIG. 1. The control device 30 takes as inputs the voltage Vac obtained from the utility power supply 1 by the voltage detector 41, the voltage Vpv obtained from the solar cell 2 by the voltage detector 42, the voltage Vbat obtained from the storage battery 3 by the voltage detector 43, and the voltage Vbus obtained from the DC bus circuit 17 by the voltage detector 44, and includes subtractors 31 to 34 that subtract the voltage command value Vdc* output from the voltage command unit 35 from each of the inputs, and a DC voltage setting unit 36 that outputs voltage command values Va* to Vd* to the power supply circuits 21 to 24 according to the outputs of the subtractors 31 to 34.

[0016] Next, the operation of the control power supply generation unit 20 configured as described above will be described. FIG. 4 is a diagram showing the magnitude relationship of the power supply voltages of the power supply sources in FIG. 1. In FIG. 4A, for example, when the AC voltage Vac of the utility power supply 1 is 400 VAC, the peak voltage of the voltage Vac is approximately 565 V. Further, the operation will be described when the voltage Vpv obtained from the solar cell 2 is 230 VDC, the DC voltage Vbat of the storage battery 3 is 266 VDC, and the DC voltage Vbus of the DC bus circuit 17 is 690 VDC.

[0017] FIG. 5 is a diagram for explaining the selection of the maximum voltage. FIG. 5A is a flowchart for maximum voltage selection, and FIGS. 5B and 5C are conceptual diagrams showing the procedure for aligning the input values. The control device 30 shown in FIG. 3 takes as inputs the voltage Vac obtained from the utility power supply 1 by the voltage detector 41, the voltage Vpv obtained from the solar cell 2 by the voltage detector 42, the voltage Vbat obtained from the storage battery 3 by the voltage detector 43, and the voltage Vbus obtained from the DC bus circuit 17 by the voltage detector 44, and subtracts the voltage command value Vdc* output from the voltage command unit 35 by the subtractors 31 to 34. Here, the following relationships hold for the respective voltages. V’ac = Vac - Vdc* V’pv = Vpv - Vdc* V’bat = Vbat - Vdc* V’bus = Vbus - Vdc*

[0018] The DC voltage setting unit 36 counts the input values that take positive numbers among the voltages V’ac, V’pv, V’bat, and V’bus (step S100). As shown in FIG. 4A, since all the voltages Vac, Vpv, Vbat, and Vbus are larger than the voltage command value Vdc*, the voltages V’ac, V’pv, V’bat, and V’bus obtained by subtracting the voltage command value Vdc* are all counted as positive values.

[0019] Next, one maximum value is selected from the unaligned positive input values (step S110), and the positive input values are sorted in descending order (step S120). In FIG. 5B, since the voltage V’bus is the maximum value, in order to make this value the first, V’ac and V’bus are swapped. The swapped V’ac and V’pv are compared, and if V’ac is larger, V’ac and V’pv are swapped. In this way, comparison operations are performed until all the counted positive input values are sorted (step S130).

[0020] In FIG. 5B, the condition shown in the following (Equation 1) is satisfied, and the DC voltage V’pv obtained from the solar cell 2 is selected as the lowest voltage. V’bus > V’ac > V’bat > V’pv > 0 ···(Equation 1)

[0021] From the calculation result of (Equation 1), the DC voltage setting unit 36 outputs the voltage command value Va* to the power supply circuit 21, the voltage command value Vb* to the power supply circuit 22, the voltage command value Vc* to the power supply circuit 23, and the voltage command value Vd* to the power supply circuit 24, respectively. Here, the following magnitude relationship as shown in (Equation 2) is set for the voltage command values. That is, the voltage command value Vb* is set so that the difference V[4] (see FIG. 4A) between the selected V’pv and the voltage command value Vb* is the smallest. From the condition of (Equation 1), each voltage command value is set so that the difference V[i] between the sorted input value and the voltage command value becomes small (step S140), and it becomes as shown in (Equation 2). Vb* > Vc* > Va* > Vd* ···(Equation 2)

[0022] As described above, the outputs of the power supply circuits 21 to 24 are compared with diodes, and the output voltage Vb of the power supply circuit 22 is input to the control power supply circuit 25 according to the relationship of (Equation 2).

[0023] On the other hand, in FIG. 4B, the operation when the voltage Vpv obtained from the solar cell 2 is DC175V due to changes in the meteorological environment such as solar radiation amount will be described. The DC voltage setting unit 36 counts the input values that take positive numbers among V’ac, V’pv, V’bat, and V’bus (step S100). In this case, since V’pv is a negative value, it is excluded from the alignment target.

[0024] One maximum value is selected from the unaligned values (step S110), and the voltage V’ac, V’bat, and V’bus are sorted in descending order as input values that take positive numbers (step S120). In FIG. 5C, since V’bus is the maximum value, in order to make this value the first, V’ac and V’bus are swapped. The swapped V’ac and V’bat are compared, and if V’ac is larger, V’ac and V’bat are swapped. In this way, the comparison operation is performed until all the counted input values are sorted (step S130).

[0025] In FIG. 5C, the condition of (Equation 3) shown below is satisfied, and the DC voltage V’bat obtained from the storage battery 3 is selected as the lowest voltage. V’bus > V’ac > V’bat > 0 ···(Equation 3)

[0026] From the calculation result of (Equation 3), the DC voltage setting unit 36 outputs the voltage command value Va* to the power supply circuit 21, a stop command to the power supply circuit 22, the voltage command value Vc* to the power supply circuit 23, and the voltage command value Vd* to the power supply circuit 24, respectively. Here, the following magnitude relationship as shown in Equation (4) is set for the voltage command values. That is, the voltage command value Vc* is set so that the difference V[3] (see FIG. 4B) between the selected V’bat and the voltage command value Vc* is minimized. From the condition of (Equation 3), when the voltage command value is set so that the difference V[i] between the sorted input value and the voltage command value is minimized, it becomes as in (Equation 4). Vc* > Va* > Vd* ···(Equation 4)

[0027] As described above, the outputs of the power supply circuits 21 to 24 are compared with each other by diodes, and from the relationship of (Equation 4), the output voltage Vc of the power supply circuit 22 is input to the control power supply circuit 25. In this way, in order to make the control device 30 recognize the magnitude relationship of the voltage values, they are arranged in descending order, and by the control device 30 holding the magnitude relationship of the voltage values, even if Vpv and Vac disappear due to changes in the solar radiation amount and a power outage in the AC system, another power supply source can be immediately selected, and it becomes possible to suppress the power consumption of the control power supply without stopping the system in response to voltage fluctuations of the power supply source.

[0028] FIG. 6 is a circuit diagram showing an example of the power supply circuits 21 and 22 provided in the control power supply generation unit 20. The power supply circuit 21 constitutes a DC / DC converter circuit that can electrically insulate the voltage Vac obtained from the utility power supply 1 and the output voltage, and the power supply circuit 22 constitutes a DC / DC converter circuit that can electrically insulate the voltage Vpv obtained from the solar cell 2 and the output voltage.

[0029] The output stage of the power supply circuit 21 has an output voltage setting unit 211 composed of a shunt regulator IC1 and a plurality of resistors R11 and R12, and the following relationship of (Equation 5) holds for the output voltage Va. Va = Vref × (R11 + R12) / R12 ···(Equation 5)

[0030] Receiving the voltage command value Va* output from the DC voltage setting unit 36, the output voltage Va can be adjusted by making the resistance value of the resistor R11 shown in (Equation 5) variable. Similarly, the power supply circuit 22 shown in FIG. 6 also has an output voltage setting unit 221. Further, although not shown in FIG. 6, the power supply circuits 23 and 24 are also configured in the same way, and the output voltages corresponding to the voltage command values can be adjusted by the voltage setting units each of them has.

[0031] As described above, in Embodiment 1, by generating the control power supply of the DC power distribution system from a plurality of power supply sources, it is possible to continue the operation of the system even in the event of an abnormality due to equipment failure or power outage, and since a power supply source with a small input / output difference in the power supply circuit is selected, the power consumption of the control power supply can be suppressed with respect to the voltage fluctuation of the power supply source. In addition, in this embodiment, a configuration in which three electrical loads are connected to the DC power distribution system is shown, but it goes without saying that the same effect can be obtained even if the number of electrical loads is further increased.

[0032] Embodiment 2. FIG. 7 is another example of the power supply circuit provided in the control power supply generation unit 20. The power supply circuit 21a constitutes a DC / DC converter circuit that can electrically insulate the voltage Vac obtained from the utility power supply 1 and the voltage Vpv obtained from the solar cell 2 from the output voltage.

[0033] The output stage of the power supply circuit 21a has an output voltage setting unit 211a including a shunt regulator IC1, a plurality of resistors R11, R12, R13, and an open / close switch S1, and the open / close switch S1 switches between a conducting state and an open state according to the output signal of the control device 30. Similarly, the power supply circuit 22a shown in FIG. 7 also has an output voltage setting unit 221a. Furthermore, although not shown in FIG. 7, other power supply circuits, that is, a power supply circuit that takes the voltage Vbat obtained from the storage battery 3 as an input and a power supply circuit that takes Vbus obtained from the DC bus circuit 17 as an input may be configured in the same manner.

[0034] Hereinafter, the operation of the power supply circuit 21a will be described, but other power supply circuits having the same configuration perform the same operation. When the open / close switch S1 is in the conducting state, the following relationship (Equation 6) holds for the output voltage Va. Va = Vref × (R11 × R13 / (R11 + R13) + R12) / R12 ··· (Equation 6)

[0035] On the other hand, when the open / close switch S1 is in the open state, the following relationship (Equation 7) holds for the output voltage Va. Va = Vref × (R11 + R12) / R12 ···(Equation 7)

[0036] By switching the conduction state and the open state of the on - off switch according to the calculation result of the control device 30, the output voltage of each power supply circuit changes according to (Equation 6) or (Equation 7).

[0037] As described above, in Embodiment 2, the control power supply of the DC power distribution system is generated from a plurality of power supply sources, and output voltage setting units 211a and 221a, which are composed of a shunt regulator, a plurality of resistors, and an on - off switch, are provided for the outputs of each power supply circuit provided in the control power supply generation unit 20. Thus, the output voltages of the plurality of power supply circuits can be switched. Therefore, even in the event of an abnormality due to equipment failure or power outage, the operation of the system can be continued while the power required for the control power supply can be selected from a desired power supply source. In this embodiment, the on - off switches S1 and S2 are illustrated as switches with mechanical movement, but it goes without saying that the same effect can be obtained by using an electrical semiconductor switch to switch between the conduction state and the open state. In addition, by increasing the switching resistors, the same switching as the variable resistor shown in Embodiment 1 can be achieved.

[0038] Embodiment 3. Hereinafter, the configuration of the DC power distribution system according to Embodiment 3 will be described. FIG. 8 is an overall configuration diagram of the DC power distribution system according to Embodiment 3. The DC power distribution system includes a power conversion device 10 connected between a plurality of power supply sources such as a utility power supply 1, a solar cell 2, and a storage battery 3, and a plurality of electrical loads 4 - 6, and has a control power supply generation unit 20A that supplies control power to a plurality of circuits built in the power conversion device 10.

[0039] The control power supply generation unit 20A takes as inputs the voltage Vac obtained from the utility power supply 1, the voltage Vpv obtained from the solar cell 2, the voltage Vbat obtained from the storage battery 3, and the voltage Vbus obtained from the DC bus circuit 17, and includes power supply circuits 21 to 24 that output a preset control power supply Vdc, and circuits that supply control power to a plurality of DC / DC converter circuits 12, 14 to 16, a bidirectional AC / DC converter circuit 11, and a charge / discharge circuit 13 built in the power conversion device 10, and opening / closing switches 26 to 29 that switch between a conductive state and an open state.

[0040] FIG. 9 is a functional block diagram of the control device 30A according to Embodiment 3. The control device 30A takes as inputs the voltage Vac obtained from the utility power supply 1 by the voltage detector 41, the voltage Vpv obtained from the solar cell 2 by the voltage detector 42, the voltage Vbat obtained from the storage battery 3 by the voltage detector 43, and the voltage Vbus obtained from the DC bus circuit 17 by the voltage detector 44, and includes subtractors 31a to 34a that subtract the voltage command value Vdc* output from the voltage command unit 35 from each input, and a control unit 37 that outputs a signal for switching between the conductive state and the open state of the opening / closing switches 26 to 29.

[0041] FIG. 10 is a time chart showing the magnitude relationship of the power supply voltage and the operation of the opening / closing switches according to Embodiment 3. First, at time t0, since the voltage Vpv obtained from the solar cell 2 is larger than the voltage command value Vdc* and the voltage difference is the smallest, the opening / closing switch 27 shown in FIG. 9 is set to the conductive state, and the other opening / closing switches 26, 28, and 29 are set to the open state.

[0042] Next, at time t1, when the voltage Vpv obtained from the solar cell 2 falls below the voltage command value Vdc* due to a change in the solar irradiance or the like, the opening / closing switch 27 is set to the open state and the opening / closing switch 28 is set to the conductive state. By this operation, the control power supply Vdc can be obtained from the voltage Vbat obtained from the storage battery 3, which is larger than the voltage command value Vdc* and has the smallest voltage difference.

[0043] Furthermore, even when the voltage Vac obtained from the utility power supply 1 disappears due to the influence of a power outage or the like at time t2, the control power supply Vdc is continuously obtained from the voltage Vbat obtained from the storage battery 3. Finally, when the voltage Vpv obtained from the solar cell 2 exceeds the voltage command value Vdc* at time t3 due to a change in the solar radiation amount or the like, the open / close switch 28 is set to the open state and the open / close switch 27 is set to the conductive state.

[0044] As described above, in the DC power distribution system and its control power supply device according to the third embodiment, the control power supply of the system is generated from a plurality of power supply sources, and an electric circuit for supplying the control power supply is provided at the output of a power supply circuit that outputs a preset control power supply Vdc. By providing open / close switches 26 to 29 that switch between the conductive state and the open state, the system can continue to operate even in the event of an abnormality due to equipment failure or a power outage, and a power supply source with a small input / output difference in the power supply circuit is selected. Therefore, the power consumption of the control power supply can be suppressed against voltage fluctuations of the power supply source. In this embodiment, the open / close switch is illustrated as a switch with mechanical movement. Needless to say, the same effect can be obtained by using an electrical semiconductor switch to switch between the conductive state and the open state.

[0045] The DC voltage setting unit 36 of Embodiment 1 and the control unit 37 of Embodiment 3 may be configured from a processor 100 and a storage device 101 as an example of hardware as shown in FIG. 11. Although not shown, the storage device 101 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Further, an auxiliary storage device of a hard disk may be provided instead of the flash memory. As the processor 100, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), an FPGA (Field Programmable Gate Array), various logic circuits, various signal processing circuits, etc. may be provided. Further, as the processor 100, a plurality of the same type or different types may be provided, and each process may be executed in a shared manner.

[0046] Although various exemplary embodiments and examples are described in the present application, the various features, aspects, and functions described in one or more of the embodiments are not limited to the application of a specific embodiment, but are applicable to the embodiments alone or in various combinations. Accordingly, countless variations not illustrated are envisioned within the scope of the technology disclosed in the specification of the present application. For example, it is assumed to include cases where at least one component is modified, added, or omitted, and further cases where at least one component is extracted and combined with components of other embodiments.

Description of Reference Numerals

[0047] 1: System power supply, 2: Solar cell, 3: Storage battery, 4, 5, 6: Electrical load, 10: Power conversion device, 11: Bidirectional AC / DC converter circuit, 12, 14, 15, 16: DC / DC converter circuit, 13: Charge and discharge circuit, 17: DC bus circuit, 20, 20A: Control power generation unit, 21, 21a, 22, 22a, 23, 24: Power supply circuit, 25: Control power supply circuit, 26, 27, 28, 29: Switch, 30, 30A: Control device, 35: Voltage command unit, 36: DC voltage setting unit, 37: Control unit, 41, 42, 43, 44: Voltage detector.

Claims

1. In a DC power distribution system in which a power distribution network for supplying power from a plurality of power supply sources to a plurality of electrical loads is formed, a power conversion circuit connected between the plurality of power supply sources and the plurality of electrical loads and supplying power according to the electrical loads, and a control power supply generation unit for supplying a control power supply for controlling the power conversion circuit are provided. The control power supply generation unit includes a control device that inputs the detected voltage of each power supply source and sets a voltage command value according to the detected voltage when the input detected voltage is greater than a predetermined value, a plurality of power supply circuits connected to each power supply source and outputting a DC voltage converted according to the voltage command value, and a control power supply circuit that supplies a control power supply based on one of the outputs of the plurality of power supply circuits to the power conversion circuit. The control device is characterized in that the voltage command value corresponding to the lowest voltage among the detected voltages greater than the predetermined value is set to the largest value. A DC power distribution system.

2. The plurality of power supply circuits are configured with DC / DC converter circuits capable of electrically insulating the voltage from the power supply source and the output voltage. The output stage has an output voltage setting unit including a shunt regulator, a plurality of resistors, and an open / close switch. The open / close switch is switched between a conductive state and an open state by an output signal of the control device. The DC power distribution system according to claim 1.

3. In a DC power distribution system in which a power distribution network for supplying power from a plurality of power supply sources to a plurality of electrical loads is formed, a power conversion circuit connected between the plurality of power supply sources and the plurality of electrical loads and supplying power according to the electrical loads, and a control power supply generation unit for supplying a control power supply for controlling the power conversion circuit are provided. The control power supply generation unit includes a plurality of power supply circuits connected to each power supply source and outputting a DC voltage, and a control device that inputs the detected voltage of each power supply source and supplies the DC voltage output of the power supply circuit corresponding to the lowest voltage among the detected voltages greater than a predetermined value as a control power supply to the power conversion circuit. A DC power distribution system characterized by comprising.

4. The DC power distribution system according to any one of claims 1 to 3, wherein the plurality of power supply sources and the plurality of electrical loads are connected by a DC bus circuit.

5. The DC power distribution system according to any one of claims 1 to 3, characterized in that the plurality of power supply sources include at least two of a utility power supply, a storage battery, and a solar cell.

6. A control power supply generation device that supplies a control power supply for controlling a power conversion circuit that is connected between a plurality of power supply sources and a plurality of electrical loads and supplies power according to the electrical load to form a power distribution network for supplying power from the plurality of power supply sources to the plurality of electrical loads, the control power supply generation device comprising: a control device that inputs the detected voltage of each power supply source and sets a voltage command value corresponding to the detected voltage when the input detected voltage is greater than a predetermined value; a plurality of power supply circuits that are connected to each power supply source and output a DC voltage converted according to the voltage command value; and a control power supply circuit that supplies a control power supply based on one of the outputs of the plurality of power supply circuits to the power conversion circuit, wherein the control device sets the voltage command value corresponding to the lowest voltage among the detected voltages greater than the predetermined value to the largest value.

7. A control power supply generation device that supplies a control power supply for controlling a power conversion circuit that is connected between a plurality of power supply sources and a plurality of electrical loads and supplies power according to the electrical load to form a power distribution network for supplying power from the plurality of power supply sources to the plurality of electrical loads, the control power supply generation device comprising: a plurality of power supply circuits that are connected to each power supply source and output a DC voltage; and a control device that inputs the detected voltage of each power supply source and supplies the DC voltage output of the power supply circuit corresponding to the lowest voltage among the detected voltages greater than a predetermined value as a control power supply to the power conversion circuit.

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