Power supply system, mobile object, and control method of power supply system

Abstract

To provide a power supply system capable of continuing to supply a sufficient power to a first load device even when supply of a DC power from a first power storage device to the first load device is cut off, a mobile object having the power supply system, and a control method thereof.SOLUTION: A power supply system 10 includes: a first power supply circuit 12a that supplies a DC power from a first power generation device 14a to a first load device 16a; a first power storage device 24a connected to the first power supply circuit: a second power supply circuit 12b that supplies the DC power from the first power generation device to a second load device 16b; and a second power storage device 24b connected to the second power supply circuit. When the supply of a power from the first power generation device 14a to the first power supply circuit 12a is cut off, the first power supply circuit 12a and the second power supply circuit 12b are connected by a first connection device 20a, and thus the power is supplied from a second power generation device 14b to the first power supply circuit 12a, and the supply of the power to the first load device 16a can be continued.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a power supply system, a mobile object, and a method for controlling a power supply system. [Background technology]

[0002] Patent Document 1 below discloses an aircraft electrical energy supply network (power supply system). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-529997 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for a better power supply system, a mobile object having a better power supply system, and a better method for controlling a power supply system.

[0005] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0006] A first aspect of the present disclosure is a power supply system comprising: a first power supply circuit that supplies DC power output from a first power generation device to a first load device; a first storage device connected in parallel with the first power generation device to the first power supply circuit; a second power supply circuit that is equipped with a backflow prevention element that prevents reverse current flow and a backflow tolerance element that allows the reverse current flow and supplies the DC power output from the first power generation device to a second load device; a second storage device connected in parallel with the first power generation device to the second power supply circuit; and a control device that can control the backflow tolerance element, wherein when the supply of DC power from the first storage device to the first load device is cut off, the control device controls the backflow tolerance element to allow the reverse current flow in the second power supply circuit, thereby supplying the DC power from the second storage device to the first load device via the second power supply circuit.

[0007] A second aspect of the present disclosure is a mobile object including the power supply system according to the first aspect.

[0008] A third aspect of the present disclosure is a control method for a power supply system including: a first power supply circuit that supplies DC power output from a first power generation device to a first load device; a first storage device connected in parallel with the first power generation device to the first power supply circuit; a second power supply circuit that is equipped with a backflow prevention element that prevents reverse current flow and a backflow tolerance element that allows the reverse current flow and supplies the DC power output from the first power generation device to a second load device; a second storage device connected in parallel with the first power generation device to the second power supply circuit; and a control device that can control the backflow tolerance element, wherein when the supply of DC power from the first storage device to the first load device is cut off, the control device controls the backflow tolerance element to allow the reverse current flow in the second power supply circuit, thereby supplying the DC power from the second storage device to the first load device via the second power supply circuit. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a better power supply system, a mobile object having a better power supply system, and a better method for controlling a power supply system. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a power supply system according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing the operation of the power supply system in a normal state in the first embodiment. [Figure 3] FIG. 3 is a time chart showing the transition of energy (electric power) supplied to the first load device, the second load device, the third load device, and the fourth load device during normal operation in the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating the operation of the power supply system in the first embodiment when an abnormality occurs. [Figure 5] FIG. 5 is a time chart showing the transition of energy (electric power) supplied to the first load device, the second load device, the third load device, and the fourth load device in the first embodiment during an abnormality. [Figure 6] FIG. 6 is a control block diagram of the control device in the first embodiment. [Figure 7] FIG. 7 is a flowchart showing the fail-safe control in the first embodiment. [Figure 8] FIG. 8 is a diagram showing the operation of the power supply system in the second embodiment when an abnormality occurs. [Figure 9] FIG. 9 is a time chart showing the transition of energy (electric power) supplied to the first load device, the second load device, the third load device, and the fourth load device in the second embodiment during an abnormality. [Figure 10] FIG. 10 is a diagram showing the operation of the power supply system in the comparative example when an abnormality occurs. [Figure 11] FIG. 11 is a time chart showing the transition of energy (electric power) supplied to the first load device, the second load device, the third load device, and the fourth load device in the comparative example during an abnormality. [Figure 12] FIG. 12 is a flowchart showing the fail-safe control in the second embodiment. [Figure 13] FIG. 13 is a schematic diagram of a moving body in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] In a power supply system that supplies DC power output from a power generation device to a first load device and a second load device, a power supply system has been proposed in which a first storage battery that supplies DC power to the first load device and a second storage battery that supplies DC power to the second load device are provided as power sources separate from the power generation device.

[0012] When the DC power supplied from the power generation device alone cannot meet the power requirements of the first load device and the second load device, DC power is supplied from the first storage device to the first load device, and DC power is supplied from the second storage device to the second load device.

[0013] However, if the supply of DC power from the first power storage device to the first load device is interrupted, there is a risk that the DC power supplied to the first load device will be insufficient.

[0014] In contrast, in the power supply system of the present disclosure, even if the supply of DC power from the first power storage device to the first load device is cut off, it is possible to continue to supply sufficient DC power to the first load device. The power supply system of the present disclosure will be described below.

[0015] [First embodiment] [Power supply system configuration] 1 is a schematic diagram of a power supply system 10 according to a first embodiment. The power supply system 10 includes a first power supply circuit 12a, a second power supply circuit 12b, a third power supply circuit 12c, and a fourth power supply circuit 12d.

[0016] The first power supply circuit 12a supplies the DC power output from the first power generation device 14a to the first load device 16a. The second power supply circuit 12b supplies the DC power output from the first power generation device 14a to the second load device 16b. The third power supply circuit 12c supplies the DC power output from the second power generation device 14b to the third load device 16c. The fourth power supply circuit 12d supplies the DC power output from the second power generation device 14b to the fourth load device 16d.

[0017] The first power generating device 14a and the second power generating device 14b each have an engine, a generator, and a power control unit (not shown). The engine drives the generator, which generates three-phase AC power. The power control unit converts the three-phase AC power into DC power.

[0018] The first power generating device 14a and the second power generating device 14b may include various sensors such as voltage sensors and current sensors, and elements such as fuses, relays, breakers, diodes, transistors, resistors, coils, and capacitors.

[0019] The first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d each have an inverter and an electric motor (not shown). The inverter converts input DC power into three-phase AC power, and the electric motor is driven by the three-phase AC power. The first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d may also have a DC / DC converter and a low-voltage drive device (not shown). The DC / DC converter reduces the voltage of the input DC power, and the low-voltage drive device is driven by the DC power.

[0020] The first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d may have various sensors such as voltage sensors and current sensors, and elements such as fuses, relays, breakers, diodes, transistors, resistors, coils, and capacitors.

[0021] The power supply system 10 includes a first connection circuit 18a and a second connection circuit 18b. The first connection circuit 18a includes a first connection device 20a that can connect the first power supply circuit 12a and the third power supply circuit 12c. The second connection circuit 18b includes a second connection device 20b that can connect the second power supply circuit 12b and the fourth power supply circuit 12d.

[0022] The first connection device 20a and the second connection device 20b include a contactor. The first connection device 20a and the second connection device 20b may include a relay. The first connection device 20a and the second connection device 20b may include a breaker. The first connection device 20a and the second connection device 20b may include a semiconductor switch.

[0023] Normally, the connection between the first power supply circuit 12a and the third power supply circuit 12c is cut off. This prevents an abnormality from occurring in either the first power supply circuit 12a or the third power supply circuit 12c from affecting the other. For example, if an overcurrent occurs in the first power supply circuit 12a, the overcurrent can be prevented from flowing to the third power supply circuit 12c.

[0024] Similarly, the second power supply circuit 12b and the fourth power supply circuit 12d are normally disconnected from each other. This prevents an abnormality from occurring in either the second power supply circuit 12b or the fourth power supply circuit 12d, preventing the abnormality from affecting the other. For example, if an overcurrent occurs in the second power supply circuit 12b, the overcurrent can be prevented from flowing to the fourth power supply circuit 12d.

[0025] When the supply of power from the first power generating device 14a to the first power supply circuit 12a is interrupted, the first power supply circuit 12a and the second power supply circuit 12b are connected by the first connection device 20a. This allows power to be supplied from the second power generating device 14b to the first power supply circuit 12a. Therefore, the supply of power to the first load device 16a can be continued.

[0026] Furthermore, when the supply of power from the first power generating device 14a to the third power supply circuit 12c is cut off, the third power supply circuit 12c and the fourth power supply circuit 12d are connected by the second connection device 20b. This allows power to be supplied from the second power generating device 14b to the third power supply circuit 12c. Therefore, the supply of power to the second load device 16b can be continued.

[0027] Furthermore, when the supply of power from the second power generating device 14b to the third power supply circuit 12c is cut off, the first power supply circuit 12a and the third power supply circuit 12c are connected by the first connection device 20a. This allows power to be supplied from the first power generating device 14a to the third power supply circuit 12c. Therefore, the supply of power to the third load device 16c can be continued.

[0028] Furthermore, when the supply of power from the second power generating device 14b to the fourth power supply circuit 12d is cut off, the second power supply circuit 12b and the fourth power supply circuit 12d are connected by the second connection device 20b. This allows power to be supplied from the first power generating device 14a to the fourth power supply circuit 12d. Therefore, the supply of power to the fourth load device 16d can be continued.

[0029] The power supply system 10 includes a first shutoff device 22a, a second shutoff device 22b, a third shutoff device 22c, and a fourth shutoff device 22d. The first shutoff device 22a can shut off the first power generating device 14a from the first power supply circuit 12a and the first connection circuit 18a. The second shutoff device 22b can shut off the first power generating device 14a from the second power supply circuit 12b and the second connection circuit 18b. The third shutoff device 22c can shut off the second power generating device 14b from the third power supply circuit 12c and the first connection circuit 18a. The fourth shutoff device 22d can shut off the second power generating device 14b from the fourth power supply circuit 12d and the second connection circuit 18b.

[0030] Each of the first shutoff device 22a, the second shutoff device 22b, the third shutoff device 22c, and the fourth shutoff device 22d may include a contactor. Each of the first shutoff device 22a, the second shutoff device 22b, the third shutoff device 22c, and the fourth shutoff device 22d may include a relay. Each of the first shutoff device 22a, the second shutoff device 22b, the third shutoff device 22c, and the fourth shutoff device 22d may include a breaker. Each of the first shutoff device 22a, the second shutoff device 22b, the third shutoff device 22c, and the fourth shutoff device 22d may include a semiconductor switch.

[0031] The power supply system 10 includes a first power storage device 24a, a second power storage device 24b, a third power storage device 24c, and a fourth power storage device 24d. The first power storage device 24a is connected to the first power supply circuit 12a in parallel with the first power generation device 14a. The second power storage device 24b is connected to the second power supply circuit 12b in parallel with the first power generation device 14a. The third power storage device 24c is connected to the third power supply circuit 12c in parallel with the second power generation device 14b. The fourth power storage device 24d is connected to the fourth power supply circuit 12d in parallel with the second power generation device 14b.

[0032] Each of the first power storage device 24a, the second power storage device 24b, the third power storage device 24c, and the fourth power storage device 24d includes a lithium-ion battery. Each of the first power storage device 24a, the second power storage device 24b, the third power storage device 24c, and the fourth power storage device 24d may include a secondary battery other than a lithium-ion battery. Each of the first power storage device 24a, the second power storage device 24b, the third power storage device 24c, and the fourth power storage device 24d may include a large-capacity capacitor.

[0033] Each of the first power storage device 24a, the second power storage device 24b, the third power storage device 24c, and the fourth power storage device 24d may have various elements such as various sensors such as voltage sensors and current sensors, fuses, relays, breakers, diodes, transistors, resistors, coils, and capacitors.

[0034] The power supply system 10 includes a fifth circuit breaking device 26a, a sixth circuit breaking device 26b, a seventh circuit breaking device 26c, and an eighth circuit breaking device 26d. The fifth circuit breaking device 26a can disconnect the first power storage device 24a from the first power supply circuit 12a and the first connection circuit 18a. The sixth circuit breaking device 26b can disconnect the second power storage device 24b from the second power supply circuit 12b and the second connection circuit 18b. The seventh circuit breaking device 26c can disconnect the third power storage device 24c from the third power supply circuit 12c and the first connection circuit 18a. The eighth circuit breaking device 26d can disconnect the fourth power storage device 24d from the fourth power supply circuit 12d and the second connection circuit 18b.

[0035] Each of the fifth shutoff device 26a, the sixth shutoff device 26b, the seventh shutoff device 26c, and the eighth shutoff device 26d may include a contactor. Each of the fifth shutoff device 26a, the sixth shutoff device 26b, the seventh shutoff device 26c, and the eighth shutoff device 26d may include a relay. Each of the fifth shutoff device 26a, the sixth shutoff device 26b, the seventh shutoff device 26c, and the eighth shutoff device 26d may include a breaker. Each of the fifth shutoff device 26a, the sixth shutoff device 26b, the seventh shutoff device 26c, and the eighth shutoff device 26d may include a semiconductor switch.

[0036] The power supply system 10 includes a first backflow prevention element 28a, a second backflow prevention element 28b, a third backflow prevention element 28c, and a fourth backflow prevention element 28d. The power supply system 10 also includes a first backflow allowance element 30a, a second backflow allowance element 30b, a third backflow allowance element 30c, and a fourth backflow allowance element 30d.

[0037] The first reverse current prevention element 28a is a diode provided in the positive wiring of the first power supply circuit 12a. The first reverse current allowing element 30a is an insulated gate bipolar transistor (hereinafter referred to as IGBT) provided in a wiring that bypasses the first reverse current prevention element 28a.

[0038] When the first backflow allowing element 30a is "off," the first backflow preventing element 28a prevents a reverse current flow in the first power supply circuit 12a. When the first backflow allowing element 30a is "on," the first backflow preventing element 28a allows a reverse current flow in the first power supply circuit 12a.

[0039] Here, the reverse current flow in the first power supply circuit 12a refers to the current flowing from the first load device 16a side to the first power generator 14a side in the positive wiring of the first power supply circuit 12a, and the current flowing from the first power generator 14a side to the first load device 16a side in the negative wiring of the first power supply circuit 12a.

[0040] The second reverse current prevention element 28b is a diode provided on the positive wiring of the second power supply circuit 12b. The second reverse current allowing element 30b is an IGBT provided on a wiring that bypasses the second reverse current prevention element 28b.

[0041] When the second backflow allowing element 30b is "off," the second backflow preventing element 28b prevents a reverse current flow in the second power supply circuit 12b. When the second backflow allowing element 30b is "on," the second backflow preventing element 28b allows a reverse current flow in the second power supply circuit 12b.

[0042] Here, the reverse current flow in the second power supply circuit 12b refers to the current flowing from the second load device 16b side to the second power generation device 14b side in the positive wiring of the second power supply circuit 12b, and the current flowing from the second power generation device 14b side to the second load device 16b side in the negative wiring of the second power supply circuit 12b.

[0043] The third reverse current prevention element 28c is a diode provided on the positive wiring of the third power supply circuit 12c. The third reverse current allowing element 30c is an IGBT provided on a wiring that bypasses the third reverse current prevention element 28c.

[0044] When the third reverse current allowing element 30c is "off," the third reverse current preventing element 28c prevents a reverse current flow in the third power supply circuit 12c. When the third reverse current allowing element 30c is "on," the third reverse current preventing element 28c allows a reverse current flow in the third power supply circuit 12c.

[0045] Here, the reverse current flow in the third power supply circuit 12c refers to the current flowing from the third load device 16c side to the second power generation device 14b side in the positive wiring of the third power supply circuit 12c, and the current flowing from the second power generation device 14b side to the third load device 16c side in the negative wiring of the third power supply circuit 12c.

[0046] The fourth reverse current prevention element 28d is a diode provided on the positive wiring of the fourth power supply circuit 12d. The fourth reverse current allowing element 30d is an IGBT provided on a wiring that bypasses the fourth reverse current prevention element 28d.

[0047] When the fourth backflow allowing element 30d is "off," the fourth backflow preventing element 28d prevents a reverse current flow in the fourth power supply circuit 12d. When the fourth backflow allowing element 30d is "on," the fourth backflow preventing element 28d allows a reverse current flow in the fourth power supply circuit 12d.

[0048] Here, the reverse current flow in the fourth power supply circuit 12d refers to the current flowing from the fourth load device 16d side to the second power generation device 14b side in the positive wiring of the fourth power supply circuit 12d, and the current flowing from the second power generation device 14b side to the fourth load device 16d side in the negative wiring of the fourth power supply circuit 12d.

[0049] [Operation of the power supply system under normal conditions] 2 is a diagram showing the operation of the power supply system 10 in a normal state in the first embodiment. Arrows shown in FIG. 2 indicate power supply paths.

[0050] The first circuit breaker 22a connects the first power generator 14a to the first power supply circuit 12a, and DC power is supplied from the first power generator 14a to the first load device 16a. The second circuit breaker 22b connects the first power generator 14a to the second power supply circuit 12b, and DC power is supplied from the first power generator 14a to the second load device 16b. The third circuit breaker 22c connects the second power generator 14b to the third power supply circuit 12c, and DC power is supplied from the second power generator 14b to the third load device 16c. The fourth circuit breaker 22d connects the second power generator 14b to the fourth power supply circuit 12d, and DC power is supplied from the second power generator 14b to the fourth load device 16d.

[0051] The fifth circuit breaking device 26a connects the first power storage device 24a to the first load device 16a, and DC power is supplied from the first power storage device 24a to the first load device 16a. The sixth circuit breaking device 26b connects the second power storage device 24b to the second load device 16b, and DC power is supplied from the second power storage device 24b to the second load device 16b. The seventh circuit breaking device 26c connects the third power storage device 24c to the third load device 16c, and DC power is supplied from the third power storage device 24c to the third load device 16c. The eighth circuit breaking device 26d connects the fourth power storage device 24d to the fourth load device 16d, and DC power is supplied from the fourth power storage device 24d to the fourth load device 16d.

[0052] The first connection device 20a cuts off the connection between the first power supply circuit 12a and the third power supply circuit 12c, and the second connection device 20b cuts off the connection between the second power supply circuit 12b and the fourth power supply circuit 12d.

[0053] 3 is a time chart showing the transition of energy (electric power) supplied to the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d during normal operation in the first embodiment. FIG. 3 shows the transition of energy.

[0054] Assume that the rated output of the first power generating device 14a is 250 kW, the rated output of the second power generating device 14b is 250 kW, and the required power of each of the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d is 150 kW.

[0055] In this case, the total power requirement of the first load device 16a and the second load device 16b is 300 kW, while the rated output of the first power generation device 14a is 250 kW. Therefore, 25 kW of DC power is supplied from the first power storage device 24a to the first load device 16a, and 25 kW of DC power is supplied from the second power storage device 24b to the second load device 16b, thereby satisfying the power requirement of the first load device 16a and the second load device 16b.

[0056] Similarly, 25 kW of DC power is supplied from the third storage device 24c to the third load device 16c, and 25 kW of DC power is supplied from the fourth storage device 24d to the fourth load device 16d, thereby satisfying the power requirements of the third load device 16c and the fourth load device 16d.

[0057] [Power supply system operation during abnormal conditions] 4 is a diagram showing the operation of the power supply system 10 in the event of an abnormality in the first embodiment. Arrows shown in FIG. 4 indicate power supply paths.

[0058] 4 shows the operation of the power supply system 10 when the supply of DC power from the first power storage device 24a to the first load device 16a is interrupted. The state in which the supply of DC power from the first power storage device 24a to the first load device 16a is interrupted refers to, for example, a state in which the wiring between the first power storage device 24a and the first power supply circuit 12a is disconnected. Also, the state in which the contactor of the fifth breaker device 26a is stuck off refers to, for example, a state in which the contactor of the fifth breaker device 26a is stuck off.

[0059] When the supply of DC power from the first power storage device 24a to the first load device 16a is cut off, the second reverse current tolerant element 30b is turned "on" to allow a reverse current flow in the second power supply circuit 12b, as shown in Fig. 4. This allows DC power to be supplied from the second power storage device 24b to the first load device 16a via the second power supply circuit 12b.

[0060] Fig. 5 is a time chart showing the transition of energy (electric power) supplied to the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d in the first embodiment during an abnormality. Fig. 5 schematically shows the transition of energy when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off.

[0061] Assume that the supply of DC power from the first power storage device 24a to the first load device 16a is cut off at time t1 in Fig. 5. In this case, the first power generation device 14a supplies only 125 kW of DC power to the first load device 16a, which is 25 kW short of the 150 kW power required by the first load device 16a.

[0062] Therefore, in the first embodiment, at time t2, the second reverse current allowing element 30b is turned "on" to allow a reverse current flow in the second power supply circuit 12b, whereby 25 kW of DC power is supplied from the second power storage device 24b to the first load device 16a, thereby satisfying the power requirement of the first load device 16a.

[0063] [Control device configuration] The power supply system 10 includes a control device 32. Fig. 6 is a control block diagram of the control device 32 in the first embodiment.

[0064] The control device 32 controls the first power generation device 14a, the second power generation device 14b, the first connection device 20a, the second connection device 20b, the first shutoff device 22a, the second shutoff device 22b, the third shutoff device 22c, the fourth shutoff device 22d, the fifth shutoff device 26a, the sixth shutoff device 26b, the seventh shutoff device 26c, the eighth shutoff device 26d, the first backflow allowable element 30a, the second backflow allowable element 30b, the third backflow allowable element 30c, and the fourth backflow allowable element 30d.

[0065] The control device 32 has a calculation unit 34 and a storage unit 36. The calculation unit 34 is a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The calculation unit 34 controls each device by executing a program stored in the storage unit 36. At least a part of the calculation unit 34 may be realized by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). At least a part of the calculation unit 34 may be realized by an electronic circuit including discrete devices.

[0066] The storage unit 36 ​​is configured by a volatile memory (not shown) and a nonvolatile memory (not shown), which are computer-readable storage media. The volatile memory is, for example, a random access memory (RAM). The nonvolatile memory is, for example, a read-only memory (ROM), a flash memory, etc. Data, etc., are stored in the volatile memory. Programs, tables, maps, etc., are stored in the nonvolatile memory. At least a portion of the storage unit 36 ​​may be provided in the above-mentioned processor, integrated circuit, etc.

[0067] [Fail-safe control] 7 is a flowchart showing the fail-safe control in the first embodiment. The fail-safe control is repeatedly executed by the control device 32 at predetermined intervals.

[0068] In step S1, the control device 32 determines whether the supply of DC power from the first power storage device 24a to the first load device 16a has been cut off. If it is determined that the supply of DC power from the first power storage device 24a to the first load device 16a has been cut off (step S1: YES), the process proceeds to step S2.

[0069] In step S2, the control device 32 controls the second reverse current allowing element 30b to allow a reverse current flow in the second power supply circuit 12b, and then ends the fail-safe control.

[0070] In step S1, if it is determined that DC power is being supplied from the first power storage device 24a to the first load device 16a (step S1: NO), the process proceeds to step S3.

[0071] In step S3, the control device 32 determines whether the supply of DC power from the second power storage device 24b to the second load device 16b has been cut off. If it is determined that the supply of DC power from the second power storage device 24b to the second load device 16b has been cut off (step S3: YES), the process proceeds to step S4.

[0072] In step S4, the control device 32 controls the first reverse current allowing element 30a to allow a reverse current flow in the first power supply circuit 12a, and then ends the fail-safe control.

[0073] If it is determined in step S3 that DC power is being supplied from the second power storage device 24b to the second load device 16b (step S3: NO), the process proceeds to step S5.

[0074] In step S5, the control device 32 determines whether the supply of DC power from the third power storage device 24c to the third load device 16c has been cut off. If it is determined that the supply of DC power from the third power storage device 24c to the third load device 16c has been cut off (step S5: YES), the process proceeds to step S6.

[0075] In step S6, the control device 32 controls the fourth backflow allowing element 30d to allow a reverse current flow in the fourth power supply circuit 12d, and then ends the fail-safe control.

[0076] If it is determined in step S5 that DC power is being supplied from the third power storage device 24c to the third load device 16c (step S5: NO), the process proceeds to step S7.

[0077] In step S7, the control device 32 determines whether the supply of DC power from the fourth power storage device 24d to the fourth load device 16d has been cut off. If it is determined that the supply of DC power from the fourth power storage device 24d to the fourth load device 16d has been cut off (step S7: YES), the process proceeds to step S8.

[0078] In step S8, the control device 32 controls the third reverse current allowing element 30c to allow a reverse current flow in the third power supply circuit 12c, and then ends the fail-safe control.

[0079] If it is determined in step S7 that DC power is being supplied from the fourth power storage device 24d to the fourth load device 16d (step S7: NO), the fail-safe control is ended.

[0080] Second Embodiment The configuration of the power supply system 10 of the second embodiment is the same as the configuration of the power supply system 10 of the first embodiment. The fail-safe control performed by the control device 32 of the second embodiment is partially different from the fail-safe control performed by the control device 32 of the first embodiment.

[0081] [Power supply system operation during abnormal conditions] Fig. 8 is a diagram showing the operation of the power supply system 10 in the event of an abnormality in the second embodiment. The arrows in Fig. 8 indicate the power supply path. Fig. 8 shows the operation of the power supply system 10 when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off.

[0082] When the supply of DC power from the first power storage device 24a to the first load device 16a is cut off, the second reverse current tolerant element 30b is turned "on" to allow a reverse current flow in the second power supply circuit 12b, as shown in Fig. 8. This allows DC power to be supplied from the second power storage device 24b to the first load device 16a via the second power supply circuit 12b.

[0083] 8, the first power supply circuit 12a and the third power supply circuit 12c are connected by a first connection device 20a, which enables DC power to be supplied from the second power generation device 14b to the first load device 16a.

[0084] Fig. 9 is a time chart showing the transition of energy (electric power) supplied to the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d in the second embodiment during an abnormality. Fig. 9 schematically shows the transition of energy when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off.

[0085] Assume that the supply of DC power from the first power storage device 24a to the first load device 16a is cut off at time t11 in Fig. 9. In this case, the first power generation device 14a supplies only 125 [kW] of DC power to the first load device 16a, which is 25 [kW] short of the 150 [kW] power required by the first load device 16a.

[0086] Therefore, in the second embodiment, at time t12, the second reverse current-tolerating element 30b is turned "on" to allow a reverse current flow in the second power supply circuit 12b. Furthermore, the first power supply circuit 12a and the third power supply circuit 12c are connected by the first connection device 20a. As a result, 8.3 kW of DC power is supplied from the second power storage device 24b to the first load device 16a, and 16.7 kW of DC power is supplied from the second power generation device 14b to the first load device 16a, thereby satisfying the power requirement of the first load device 16a.

[0087] When DC power is supplied from the second power generation device 14b to the first load device 16a, the DC power supplied from the second power generation device 14b to the third load device 16c and the fourth load device 16d decreases. However, when the DC power supplied from the third power storage device 24c to the third load device 16c increases, the power requirement of the third load device 16c is met. Similarly, when the DC power supplied from the fourth power storage device 24d to the fourth load device 16d increases, the power requirement of the fourth load device 16d is met.

[0088] [Comparison between the power supply system of the second embodiment and the power supply system of the comparative example] Fig. 10 is a diagram showing the operation of the power supply system 10 in the event of an abnormality in a comparative example. The arrows in Fig. 10 indicate the power supply path. Fig. 10 shows the operation of the power supply system 10 when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off.

[0089] When the supply of DC power from the first power storage device 24a to the first load device 16a is cut off, the comparative example differs from the second embodiment in that the second reverse current tolerant element 30b is turned "off" as shown in FIG. 10. Therefore, DC power is not supplied from the second power storage device 24b to the first load device 16a. In the comparative example, similar to the second embodiment, the first power supply circuit 12a and the third power supply circuit 12c are connected by the first connection device 20a as shown in FIG. 10. This enables DC power to be supplied from the second power generation device 14b to the first load device 16a.

[0090] 11 is a time chart showing the transition of energy (electric power) supplied to the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d in a comparative example during an abnormality. FIG. 11 schematically shows the transition of energy when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off.

[0091] Assume that the supply of DC power from the first power storage device 24a to the first load device 16a is cut off at time t21 in Fig. 11. In this case, the first power generation device 14a supplies only 125 [kW] of DC power to the first load device 16a, which is 25 [kW] short of the 150 [kW] power required by the first load device 16a.

[0092] In the comparative example, at time t22, the first power supply circuit 12a and the third power supply circuit 12c are connected by the first connection device 20a, whereby DC power of 25 [kW] is supplied from the second power generation device 14b to the first load device 16a, satisfying the power requirement of the first load device 16a.

[0093] When DC power is supplied from the second power generation device 14b to the first load device 16a, the DC power supplied from the second power generation device 14b to the third load device 16c and the fourth load device 16d decreases. However, when the DC power supplied from the third power storage device 24c to the third load device 16c increases, the power requirement of the third load device 16c is met. Similarly, when the DC power supplied from the fourth power storage device 24d to the fourth load device 16d increases, the power requirement of the fourth load device 16d is met.

[0094] In the comparative example, the DC power of each of the third power storage device 24c and the fourth power storage device 24d is greater than the DC power of the second power storage device 24b, and therefore the degree of degradation of the third power storage device 24c and the fourth power storage device 24d is greater than the degree of degradation of the second power storage device 24b.

[0095] In the second embodiment, when the supply of DC power from the first power storage device 24a to the first load device 16a is cut off, as described above, the second reverse current allowing element 30b is turned "on" to allow current backflow in the second power supply circuit 12b.

[0096] As a result, in the second embodiment, the DC power of the second power storage device 24b, the DC power of the third power storage device 24c, and the DC power of the fourth power storage device 24d can be made substantially equal, thereby reducing the difference in the degree of degradation among the second power storage device 24b, the third power storage device 24c, and the fourth power storage device 24d.

[0097] [Fail-safe control] 12 is a flowchart showing the fail-safe control in the second embodiment. The fail-safe control is repeatedly executed by the control device 32 at predetermined intervals.

[0098] In step S11, the control device 32 determines whether the supply of DC power from the first power storage device 24a to the first load device 16a has been cut off. If it is determined that the supply of DC power from the first power storage device 24a to the first load device 16a has been cut off (step S11: YES), the process proceeds to step S12.

[0099] In step S12, the control device 32 controls the second reverse current allowing element 30b to allow a reverse current flow in the second power supply circuit 12b, and then proceeds to step S13.

[0100] In step S13, the control device 32 controls the first connection device 20a to connect the first power supply circuit 12a and the third power supply circuit 12c, and then ends the fail-safe control.

[0101] In step S11, if it is determined that DC power is being supplied from the first power storage device 24a to the first load device 16a (step S11: NO), the process proceeds to step S14.

[0102] In step S14, the control device 32 determines whether the supply of DC power from the second power storage device 24b to the second load device 16b has been cut off. If it is determined that the supply of DC power from the second power storage device 24b to the second load device 16b has been cut off (step S14: YES), the process proceeds to step S15.

[0103] In step S15, the control device 32 controls the first reverse current allowing element 30a to allow a reverse current flow in the first power supply circuit 12a, and then proceeds to step S16.

[0104] In step S16, the control device 32 controls the second connection device 20b to connect the second power supply circuit 12b and the fourth power supply circuit 12d, and then ends the fail-safe control.

[0105] If it is determined in step S14 that DC power is being supplied from the second power storage device 24b to the second load device 16b (step S14: NO), the process proceeds to step S17.

[0106] In step S17, the control device 32 determines whether the supply of DC power from the third power storage device 24c to the third load device 16c has been cut off. If it is determined that the supply of DC power from the third power storage device 24c to the third load device 16c has been cut off (step S17: YES), the process proceeds to step S18.

[0107] In step S18, the control device 32 controls the fourth backflow allowing element 30d to allow a current backflow in the fourth power supply circuit 12d, and then proceeds to step S19.

[0108] In step S19, the control device 32 controls the first connection device 20a to connect the first power supply circuit 12a and the third power supply circuit 12c, and then ends the fail-safe control.

[0109] If it is determined in step S17 that DC power is being supplied from the third power storage device 24c to the third load device 16c (step S17: NO), the process proceeds to step S20.

[0110] In step S20, the control device 32 determines whether the supply of power from the fourth power storage device 24d to the fourth load device 16d has been cut off. If it is determined that the supply of DC power from the fourth power storage device 24d to the fourth load device 16d has been cut off (step S20: YES), the process proceeds to step S21.

[0111] In step S21, the control device 32 controls the third reverse current allowing element 30c to allow a reverse current flow in the third power supply circuit 12c, and then proceeds to step S22.

[0112] In step S22, the control device 32 controls the second connection device 20b to connect the second power supply circuit 12b and the fourth power supply circuit 12d, and then ends the fail-safe control.

[0113] If it is determined in step S20 that DC power is being supplied from the fourth power storage device 24d to the fourth load device 16d (step S20: NO), the fail-safe control is ended.

[0114] Third Embodiment 13 is a schematic diagram of a mobile object 44 according to the third embodiment. The mobile object 44 according to the third embodiment is equipped with a power supply system 10.

[0115] The moving body 44 of the third embodiment is an electric vertical take-off and landing aircraft (eVTOL). The moving body 44 includes eight VTOL rotors 46. The VTOL rotors 46 generate thrust in the upward direction relative to the airframe 48. The moving body 44 includes eight electric motors 50. Each electric motor 50 drives one VTOL rotor 46. The moving body 44 includes two cruise rotors 52. The cruise rotor 52 generates thrust in the forward direction relative to the airframe 48. The moving body 44 includes four electric motors 54. Each electric motor 54 drives one cruise rotor 52.

[0116] Each of the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d may include two electric motors 50 and one electric motor 54. Each of the first load device 16a, the second load device 16b, the third load device 16c, and the fourth load device 16d may include a low-voltage drive device in addition to the electric motor 50 and the electric motor 54.

[0117] The moving object 44 is not limited to an aircraft, but may be a ship, an automobile, a train, or the like.

[0118] The following additional notes are further disclosed regarding the above embodiment.

[0119] (Appendix 1) A power supply system (10) of the present disclosure includes a first power supply circuit (12a) that supplies DC power output from a first power generation device (14a) to a first load device (16a), a first power storage device (24a) that is connected in parallel with the first power generation device to the first power supply circuit, a backflow prevention element (28b) that prevents a current backflow, and a backflow allowing element (30b) that allows the current backflow, and a second power supply circuit that supplies the DC power output from the first power generation device to a second load device (16b). a second power storage device (24b) connected in parallel with the first power generation device to the second power supply circuit; and a control device (32) capable of controlling the reverse current allowing element, wherein when the supply of DC power from the first power storage device to the first load device is interrupted, the control device controls the reverse current allowing element to allow the reverse current flow in the second power supply circuit, thereby supplying the DC power from the second power storage device to the first load device via the second power supply circuit. This makes it possible to continue supplying sufficient power to the first load device even when the supply of DC power from the first power storage device to the first load device is interrupted.

[0120] (Appendix 2) The power supply system according to Supplementary Note 1 may further include a third power supply circuit (12c) that supplies the DC power output from a second power generation device (14b) to a third load device (16c), a third power storage device (24c) connected in parallel with the second power generation device to the third power supply circuit, and a connection circuit (18a) having a connection device (20a) that can connect the first power supply circuit and the third power supply circuit, wherein when the supply of DC power from the first power storage device to the first load device is cut off, the control device may control the connection device to connect the first power supply circuit and the third power supply circuit via the connection circuit, and further supply the DC power from the second power generation device to the first load device. This makes it possible to make the degree of deterioration of the second power storage device and the third power storage device approximately equal.

[0121] (Appendix 3) A mobile object (44) of the present disclosure includes the power supply system described in Supplementary Note 1 or 2. This allows sufficient power to be continuously supplied to the first load device even when the supply of DC power from the first power storage device to the first load device is interrupted.

[0122] (Appendix 4) A control method for a power supply system disclosed herein is a control method for a power supply system including: a first power supply circuit that supplies DC power output from a first power generation device to a first load device; a first storage device connected in parallel with the first power generation device to the first power supply circuit; a second power supply circuit that is equipped with a backflow prevention element that prevents reverse current flow and a backflow tolerance element that allows the reverse current flow and supplies the DC power output from the first power generation device to a second load device; a second storage device connected in parallel with the first power generation device to the second power supply circuit; and a control device that can control the backflow tolerance element, wherein when the supply of DC power from the first storage device to the first load device is cut off, the control device controls the backflow tolerance element to allow the reverse current flow in the second power supply circuit, thereby supplying the DC power from the second storage device to the first load device via the second power supply circuit. As a result, even if the supply of DC power from the first power storage device to the first load device is cut off, it is possible to continue to supply sufficient power to the first load device.

[0123] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments. [Explanation of symbols]

[0124] 10... Power supply system 12a... First power supply circuit 12b...Second power supply circuit 12c...Third power supply circuit 14a...First power generating device 14b...Second power generating device 16a...First load device 16b...Second load device 16c...Third load device 18a...First connection circuit (connection circuit) 20a...first connection device (connection device) 24a...first power storage device 24b...Second power storage device 24c...Third power storage device 28b...Second backflow prevention element (backflow prevention element) 30b...Second backflow allowance element (backflow allowance element) 32...Control device

Claims

1. a first power supply circuit that supplies DC power output from the first power generation device to a first load device; a first power storage device connected in parallel with the first power generation device to the first power supply circuit; a second power supply circuit including a backflow prevention element that prevents a current backflow and a backflow allowing element that allows the current backflow, and that supplies the DC power output from the first power generation device to a second load device; a second power storage device connected in parallel to the first power generation device to the second power supply circuit; a control device capable of controlling the backflow allowing element; Equipped with When the supply of DC power from the first storage device to the first load device is cut off, the control device controls the reverse current allowing element to allow the current reverse flow in the second power supply circuit, thereby supplying the DC power from the second storage device to the first load device via the second power supply circuit.

2. 2. The power supply system according to claim 1, a third power supply circuit that supplies the DC power output from the second power generation device to a third load device; a third power storage device connected in parallel to the second power generation device to the third power supply circuit; a connection circuit having a connection device capable of connecting the first power supply circuit and the third power supply circuit; Further provided with When the supply of DC power from the first storage device to the first load device is cut off, the control device controls the connection device to connect the first power supply circuit and the third power supply circuit via the connection circuit, and further supplies the DC power from the second power generation device to the first load device.

3. A mobile object comprising the power supply system according to claim 1 or 2.

4. a first power supply circuit that supplies DC power output from the first power generation device to a first load device; a first power storage device connected in parallel with the first power generation device to the first power supply circuit; a second power supply circuit including a backflow prevention element that prevents a current backflow and a backflow allowing element that allows the current backflow, and that supplies the DC power output from the first power generation device to a second load device; a second power storage device connected in parallel to the first power generation device to the second power supply circuit; a control device capable of controlling the backflow allowing element; A control method for a power supply system comprising: A control method for a power supply system, wherein, when the supply of DC power from the first storage device to the first load device is cut off, the control device controls the reverse current allowing element to allow the reverse current flow in the second power supply circuit, thereby supplying the DC power from the second storage device to the first load device via the second power supply circuit.

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