Fuel cell power device

Abstract

To improve the versatility of a fuel cell power supply device.SOLUTION: A fuel cell power supply device 10 includes a fuel cell 20, an output terminal unit 40 used to output the power of the fuel cell 20 to a load 101, a power generation control circuit 70 that controls power generation of the fuel cell 20, and a circuit connection unit 71 connected to the power generation control circuit 70 and used for connection with the circuit connection unit 71, and in such a configuration, a command circuit 72 is configured to transmit a power generation command to the power generation control circuit 70 when the circuit connection unit 71 is connected to the circuit connection unit 71. The power generation control circuit 70 controls the power generation of the fuel cell 20 on the basis of the power generation command from the command circuit 72 when the command circuit 72 is connected to the circuit connection unit 71.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a fuel cell power supply device.

Background Art

[0002] Patent Document 1 discloses a fuel cell power supply device that supplies the power of a fuel cell to a load.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, fuel cell power supply devices may be designed according to various usage conditions. However, if the design of the fuel cell power supply device is changed for each usage condition, the manufacturing cost of the fuel cell power supply device will increase. In order to reduce such manufacturing costs, for example, it is conceivable to improve the versatility of the fuel cell power supply device.

Means for Solving the Problems

[0005] The fuel cell power supply device for solving the above problems includes a fuel cell, an output terminal portion used to output the power of the fuel cell to a load, a power generation control circuit that performs power generation control of the fuel cell, and a circuit connection portion that is connected to the power generation control circuit and used to connect to a command circuit. The command circuit is configured to transmit a power generation command to the power generation control circuit when connected to the circuit connection portion. The power generation control circuit performs the power generation control of the fuel cell based on the power generation command from the command circuit when the command circuit is connected to the circuit connection portion.

[0006] According to such a configuration, by connecting the command circuit, the command circuit can perform power generation control of the fuel cell via the power generation control circuit. Thereby, power generation control of the fuel cell can be performed using the command circuit. Therefore, when it is not necessary to perform power generation control of the fuel cell using the command circuit, the command circuit is not connected to the circuit connection part, while when it is desired to perform power generation control of the fuel cell using the command circuit, the command circuit may be connected to the circuit connection part. Thus, even when the usage conditions are different between the case of using the command circuit and the case of not using it, the same fuel cell power supply device can be used. Therefore, the versatility of the fuel cell power supply device can be improved.

[0007] In the above fuel cell power supply device, when the command circuit is connected to the circuit connection part, the command circuit monitors the power supply from the commercial power supply to the load, and based on the occurrence of a power failure in the commercial power supply, the command circuit is configured to transmit a start command to the power generation control circuit. The power generation control circuit may be configured to start the fuel cell based on the input of the start command from the command circuit in a situation where the command circuit is connected to the circuit connection part.

[0008] According to such a configuration, by connecting the command circuit to the circuit connection part, a power failure of the commercial power supply can be detected. Also, when a power failure of the commercial power supply occurs, the fuel cell starts up and the fuel cell functions as a backup. Therefore, by connecting the command circuit, the fuel cell power supply device can be used as an emergency power supply. Thus, further improvement in versatility can be achieved.

[0009] The above fuel cell power supply device may be provided with a power storage connection part that is connected to the output terminal part and is used for connecting a power storage device. According to such a configuration, when the power storage device is connected to the power storage connection part, a voltage can be applied from the power storage device to the load via the output terminal part. Therefore, a voltage drop can be suppressed from when the commercial power supply fails until the fuel cell starts generating power.

[0010] The fuel cell power supply device is connected to the output terminal portion and includes a power storage connection portion used to connect a power storage device. The power generation control circuit performs the power generation control of the fuel cell based on a power storage parameter corresponding to the SOC of the power storage device. The command circuit may control the power generation control circuit by transmitting a signal in the form of the power storage parameter of the power storage device to the power generation control circuit as the power generation command.

[0011] According to such a configuration, by connecting the power storage device to the power storage connection portion, the power of the power storage device can be supplied to the load. Here, if power is supplied from the power storage device to the load, the SOC of the power storage device will decrease. On the other hand, if power is not supplied from the power storage device to the load, the SOC of the power storage device will not decrease. Therefore, the SOC of the power storage device can vary according to the mode of power supply from the power storage device to the load.

[0012] In this regard, according to the present configuration, by the power generation control circuit performing power generation control based on the power storage parameter corresponding to the SOC of the power storage device, it is possible to supply the necessary power to the load without the load and the power generation control circuit directly exchanging information.

[0013] On the other hand, when the command circuit is connected to the circuit connection portion, the power generation control circuit may perform power generation control based on a power generation command from the command circuit. In this case, when a signal in a dedicated format is input from the command circuit to the power generation control circuit, it may be necessary to configure the power generation control circuit to be able to perform power generation control based on the signal in the dedicated format.

[0014] In this regard, according to this configuration, the command circuit is configured to transmit a signal in the form of a power storage parameter of the power storage device as a power generation command. Thereby, it is possible to respond to the power generation command from the command circuit by using a power generation control circuit that performs power generation control based on the power storage parameter of the power storage device. That is, a common power generation control circuit can be used whether the command circuit is connected or not. Therefore, since it is not necessary to separately prepare a power generation control circuit for responding to the power generation command from the command circuit, the versatility can be improved.

[0015] The fuel cell power supply device includes a communication connection unit used to connect to other fuel cell power supply devices, the power generation control circuit is connected to the communication connection unit, and when the power generation command of the command circuit is input via the communication connection unit, the power generation control is performed based on the power generation command. It may be such a thing.

[0016] According to such a configuration, by connecting and using a plurality of fuel cell power supply devices to each other, it is possible to output a large amount of power that cannot be output by a single fuel cell power supply device. Thereby, it is possible to respond to the usage condition of large power without separately designing a fuel cell power supply device for large power, so that the versatility can be further improved.

[0017] Here, when a plurality of fuel cell power supply devices are used, it is conceivable that the command circuit comprehensively controls each fuel cell power supply device. In this case, since the power generation control circuit performs the power generation control of the fuel cell based on the power generation command input via the communication connection unit, the command circuit only needs to transmit the power generation command to the communication connection unit. Therefore, the command circuit only needs to be provided in at least one of the plurality of fuel cell power supply devices. Thus, the configuration can be simplified.

[0018] Also, by connecting a command circuit capable of performing overall control to the circuit connection unit, the fuel cell power supply device can be used as a master device that performs overall control of a plurality of fuel cell power supply devices. Thereby, the versatility can be improved.

[0019] The above fuel cell power supply device may be provided with a connection switch that can be switched between ON and OFF, and the power storage connection portion may be connected to the fuel cell via the connection switch. According to such a configuration, by turning off the connection switch, the connection between the fuel cell and the power storage connection portion can be interrupted. Thereby, when attaching or detaching the power storage device to / from the power storage connection portion, it is possible to suppress the power of the fuel cell from being transmitted through an unexpected path via the power storage connection portion. Therefore, the safety of the fuel cell power supply device can be improved.

[0020] The above fuel cell power supply device may be provided with a changeover switch that is provided between the fuel cell and the output terminal portion and can be switched between a first connection state and a second connection state. In the first connection state, the power storage connection portion is connected to the output terminal portion via the connection switch and the changeover switch. In the second connection state, the power storage connection portion is connected to the output terminal portion without passing through the connection switch and via the changeover switch.

[0021] According to such a configuration, in the first connection state, by turning off the connection switch, the connection between the power storage connection portion and the output terminal portion can be interrupted. Thereby, when the power storage device is connected to the power storage connection portion, it is possible to switch whether to output the power of the power storage device from the output terminal portion by operating the connection switch. Therefore, when attaching or detaching the power storage device to / from the power storage connection portion, it is possible to suppress the power of the power storage device from being transmitted through an unexpected path via the output terminal portion.

[0022] Also, in the second connection state, by turning off the connection switch, the connection between the output terminal portion and the fuel cell can be interrupted. Thereby, for example, even when the load includes a battery, it is possible to prevent the power of the battery included in the load from being transmitted to the fuel cell by operating the connection switch. Therefore, for example, when performing maintenance on the fuel cell or the like, it is possible to suppress the output of the load from being transmitted through an unexpected path via the output terminal portion.

[0023] As described above, it is possible to provide a fuel cell power supply device that can achieve both an improvement in safety and an improvement in versatility capable of coping with various loads.

Effect of the Invention

[0024] According to the present invention, the versatility of the fuel cell power supply device can be improved.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

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Figure 9

Figure 10

Mode for Carrying Out the Invention

[0026] <First Embodiment> Hereinafter, a first embodiment of the fuel cell power supply device will be described. <Fuel cell power supply device 10, commercial power supply 100> As shown in FIG. 1, the fuel cell power supply device 10 is connected in parallel to, for example, the commercial power supply 100 and is used to supply power to the load 101 together with the commercial power supply 100. The commercial power supply 100 of the present embodiment outputs power of the DC voltage Vdc1 to the load 101 according to the required power P1 of the load 101. The commercial power supply 100 includes, for example, an AC / DC converter that converts the AC power of a system power supply (not shown) into the DC voltage Vdc1. Note that the specific form of the commercial power supply 100 is arbitrary, and it may include an AC / DC converter that converts the AC power supplied from an AC power supply (not shown) into DC power and supplies it to the load 101. Examples of such an AC power supply include power generation devices in power plants and substations.

[0027] The fuel cell power supply device 10 includes a fuel cell 20, a power converter 30, an output terminal portion 40, a power storage connection portion 50, a power storage device 51, a connection switch 60, a fuse 61, a changeover switch 62, a power generation control circuit 70, and a circuit connection portion 71.

[0028] <Fuel cell 20> Although not shown in the figure, the fuel cell 20 includes a fuel cell that generates power using hydrogen gas and oxygen gas as fuel, a hydrogen tank that stores hydrogen gas, a hydrogen pump that supplies the hydrogen in the hydrogen tank to the fuel cell, and an air compressor that supplies external air to the fuel cell. The fuel cell 20 can generate power according to the supply amounts of hydrogen and oxygen. Therefore, the power generation amount of the fuel cell 20 can be controlled by controlling the hydrogen pump and the air compressor.

[0029] <Power converter 30> The power converter 30 converts and outputs the power from the fuel cell 20. In the present embodiment, the power converter 30 is a DC / DC converter that outputs DC power. The voltage output from the power converter 30 is equal to or lower than the DC voltage Vdc1 output from the commercial power supply 100. The power output from the power converter 30 is also the power output from the fuel cell 20.

[0030] <Output terminal section 40> The output terminal section 40 is used to output the power of the fuel cell 20 to the load 101. The output terminal section 40 is connected to the fuel cell 20 via the power converter 30. When outputting the power of the fuel cell 20 to the load 101, the output terminal section 40 is connected to the load 101.

[0031] <Power storage connection section 50> The power storage connection section 50 is connected to the output terminal section 40. The power storage connection section 50 is used to connect the power storage device 51. The power storage connection section 50 of the present embodiment is a socket to which the power storage device 51 can be attached and detached. Note that the specific form of the power storage connection section 50 is not limited to this and is arbitrary. The fuel cell power supply device 10 of the present embodiment can be switched between a mode in which the power storage device 51 is attached and a mode in which the power storage device 51 is removed by including the power storage connection section 50.

[0032] <Power storage device 51> The power storage device 51 includes a storage battery 52, a contactor 53 interposed between the power storage connection section 50 and the storage battery 52, and a BMS 54.

[0033] <Storage battery 52> The storage battery 52 is a secondary battery that outputs DC power. Examples of the storage battery 52 include a lithium ion storage battery, a nickel hydrogen storage battery, and a lead storage battery. When the contactor 53 is ON when the power storage device 51 is connected to the power storage connection section 50, the power of the storage battery 52 is output to the output terminal section 40 via the power storage connection section 50. On the other hand, even when the power storage device 51 is connected to the power storage connection section 50, the power of the storage battery 52 is not output to the output terminal section 40 via the power storage connection section 50 when the contactor 53 is OFF.

[0034] The power storage connection section 50 is connected to the fuel cell 20 via the power converter 30. Thereby, when the power storage device 51 is connected to the power storage connection section 50, the power discharged from the power storage device 51 can be supplied to the load 101, and the power generated by the fuel cell 20 can be supplied to the power storage device 51.

[0035] <bms54> BMS54 is a Battery Management System that monitors the State of Charge (SOC) of the storage battery 52. Hereinafter, for convenience of explanation, the SOC of the storage battery 52 may be referred to as the SOC of the power storage device 51. That is, the SOC of the power storage device 51 is synonymous with the SOC of the storage battery 52.

[0036] An example of a method for monitoring the SOC of the power storage device 51 will be described. BMS54 is configured to be able to acquire the inter-terminal voltage of the power storage device 51 and stores a map showing the correspondence between the inter-terminal voltage of the power storage device 51 and the SOC of the power storage device 51. The inter-terminal voltage of the power storage device 51 is, for example, the open-circuit voltage or the closed-circuit voltage of the storage battery 52. BMS54 acquires the inter-terminal voltage of the power storage device 51 and monitors the SOC of the power storage device 51 from the acquired inter-terminal voltage by referring to the above map.

[0037] In addition to the inter-terminal voltage, BMS54 may monitor the SOC based on parameters corresponding to the SOC of the power storage device 51, such as the input / output current and input / output power of the power storage device 51, and the value obtained by subtracting the required power P1 of the load 101 from the power generation amount of the fuel cell 20. Hereinafter, for convenience of explanation, the parameters corresponding to the SOC of the power storage device 51 are referred to as power storage parameters. The power storage parameters are, for example, the inter-terminal voltage, input / output current, and input / output power of the power storage device 51. The power storage parameters may be a combination of these or the SOC of the power storage device 51 itself.

[0038] <Connection switch 60> The connection switch 60 is a switch that can be switched between ON and OFF. The power storage connection part 50 is connected to the fuel cell 20 via the connection switch 60. The connection switch 60 can switch the connection between the fuel cell 20 and the power storage connection part 50. Specifically, when the connection switch 60 is ON, the fuel cell 20 and the connection switch 60 are electrically connected. When the connection switch 60 is OFF, the fuel cell 20 and the connection switch 60 are insulated. Note that the specific form of the connection switch 60 can be arbitrarily selected, such as a mechanical switch or a relay switch.

[0039] <Fuse 61> Fuse 61 is connected in series with connection switch 60. In this embodiment, the current flowing through connection switch 60 is equal to the current flowing through fuse 61. When a current greater than a predetermined magnitude flows through fuse 61, fuse 61 turns OFF. Thereby, it is possible to suppress an excessive current from flowing from power storage device 51 and an excessive current from flowing from fuel cell 20 to power storage device 51.

[0040] <Changeover switch 62> Changeover switch 62 is provided between fuel cell 20 and output terminal portion 40. Specifically, changeover switch 62 is provided between power converter 30 and output terminal portion 40. Changeover switch 62 can switch between a first connection state and a second connection state. The changeover switch 62 of this embodiment is a single double-pole switch, but is not limited thereto, and may be a plurality of single-pole switches or a triple-pole switch.

[0041] <First connection state> In the first connection state, power storage connection portion 50 is connected to output terminal portion 40 via connection switch 60 and changeover switch 62, and output terminal portion 40 and power converter 30 are connected without passing through connection switch 60. Thereby, in the first connection state, fuel cell 20 and output terminal portion 40 are connected via power converter 30 regardless of whether connection switch 60 is ON or OFF. In the case of the first connection state, when connection switch 60 is ON, fuel cell 20 and power storage connection portion 50 are connected via power converter 30.

[0042] In the case of the first connection state, when connection switch 60 is OFF, output terminal portion 40 and power storage connection portion 50 are insulated. Therefore, the first connection state is a state in which the connection between output terminal portion 40 and power storage connection portion 50 can be changed while maintaining the connection between fuel cell 20 and output terminal portion 40 by operating the ON / OFF of connection switch 60.

[0043] <Second connection state> In the second connection state, the power storage connection unit 50 is connected to the output terminal unit 40 via the changeover switch 62 and without passing through the connection switch 60. In the case of the second connection state, the output terminal unit 40 and the power storage connection unit 50 are connected regardless of the ON / OFF state of the connection switch 60.

[0044] In the second connection state, the output terminal unit 40 is connected to the connection switch 60. Also, in the second connection state, the output terminal unit 40 is connected to the fuel cell 20 via the power converter 30. In the case of the second connection state, when the connection switch 60 is ON, the fuel cell 20 and the output terminal unit 40 are connected via the power converter 30. When the connection switch 60 is OFF, the fuel cell 20 and the output terminal unit 40 are insulated from each other. Therefore, the second connection state is a state in which, by operating the ON / OFF of the connection switch 60, the connection between the output terminal unit 40 and the power storage connection unit 50 can be maintained while the connection between the fuel cell 20 and the output terminal unit 40 can be changed.

[0045] In other words, the changeover switch 62 switches between a first connection state in which the output terminal unit 40 and the fuel cell 20 are connected without passing through the connection switch 60 and the connection switch 60 and the output terminal unit 40 are connected, and a second connection state in which the output terminal unit 40 and the fuel cell 20 are connected via the connection switch 60 and the output terminal unit 40 and the power storage connection unit 50 are connected without passing through the connection switch 60.

[0046] <Power generation control circuit 70> The power generation control circuit 70 includes a processing unit and a storage unit. The power generation control circuit 70 may include dedicated hardware for executing at least some of various processes, for example, an application specific integrated circuit (ASIC). The power generation control circuit 70 can be configured as a circuit including one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as an ASIC, or a combination thereof. The processor includes a CPU and a memory such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute processes. The memory, that is, the computer-readable medium, includes anything that can be accessed by a general-purpose or dedicated computer.

[0047] The power generation control circuit 70 controls the power generation of the fuel cell 20. The power generation control circuit 70 controls the power generation of the fuel cell 20 based on a power storage parameter corresponding to the state of charge (SOC) of the power storage device 51. In the present embodiment, the power generation control circuit 70 controls the power generation of the fuel cell 20 based on the SOC of the power storage device 51.

[0048] The power generation control of the fuel cell 20 is the control of the power generation amount of the fuel cell 20. For example, the power generation control circuit 70 controls the power generation amount of the fuel cell 20 by controlling the supply amounts of hydrogen gas and oxygen gas to the fuel cells of the fuel cell 20. Examples of the control targets of the power generation control circuit 70 include a hydrogen pump and an air compressor.

[0049] Note that a program for controlling the power generation of the fuel cell 20 based on various commands transmitted from the power generation control circuit 70 when a command circuit 72 described later is connected to the circuit connection unit 71 is pre-embedded in the power generation control circuit 70.

[0050] <Circuit connection unit 71> As shown in FIGS. 1 and 3, the circuit connection part 71 is connected to the power generation control circuit 70. The circuit connection part 71 is used to connect to a command circuit 72 described later. The circuit connection part 71 of the present embodiment is a connector to which the command circuit 72 can be attached and detached. Note that the specific connection mode between the circuit connection part 71 and the command circuit 72 is arbitrary, and the circuit connection part 71 and the command circuit 72 may be connected by soldering or the like. That is, by providing the circuit connection part 71, the fuel cell power supply device 10 of the present embodiment can be switched between a mode in which the command circuit 72 is attached and a mode in which the command circuit 72 is removed.

[0051] <Regarding the case where the command circuit 72 is not connected to the circuit connection part 71> Here, the case where the command circuit 72 is not connected to the circuit connection part 71 will be described. As shown in FIG. 1, the power generation control circuit 70 controls the power generation of the fuel cell 20 by performing a power generation process. When the power generation process is performed, the changeover switch 62 is operated so that the connection switch 60 is ON and the first connection state is established. In the present embodiment, the power storage device 51 is connected to the power storage connection part 50.

[0052] <Step S1> As shown in FIG. 2, first, in step S1, the power generation control circuit 70 obtains the SOC of the power storage device 51 from the power storage device 51, specifically, the BMS 54. For example, the power generation control circuit 70 may obtain the SOC of the power storage device 51 monitored by the BMS 54. Further, the power generation control circuit 70 may obtain the SOC of the power storage device 51 by deriving the SOC of the power storage device 51 based on the power storage parameters obtained by the BMS 54. Therefore, the mode of obtaining the SOC of the power storage device 51 is arbitrary.

[0053] <Step S2> Next, proceed to step S2, and the power generation control circuit 70 performs power generation control to control the power generation amount of the fuel cell 20 according to the SOC of the power storage device 51 acquired in step S1. The power generation control circuit 70 of the present embodiment performs multi-stage power generation in which the power generation amount of the fuel cell 20 is increased each time the SOC of the power storage device 51 falls below a certain predetermined value when the SOC of the power storage device 51 falls below the predetermined value as power generation control.

[0054] When the power storage device 51 outputs power to the load 101 according to the required power P1, the SOC of the power storage device 51 decreases as power is supplied from the power storage device 51 to the load 101. Therefore, the decrease amount of the SOC of the power storage device 51 reflects the required power P1 of the load 101. Therefore, by performing the above multi-stage power generation by the power generation control circuit 70, the fuel cell 20 and the power storage device 51 can supply power corresponding to the required power P1 of the load 101 to the load 101. Therefore, when performing power generation control based on the SOC of the power storage device 51, the power generation control circuit 70 does not have to directly acquire the required power P1 of the load 101 from the load 101.

[0055] After executing the power generation control, the power generation control circuit 70 ends the power generation process. Note that the power generation process is repeatedly performed while the fuel cell power supply device 10 is operating. In this way, when the command circuit 72 is not connected to the circuit connection portion 71, the fuel cell power supply device 10 performs power generation control of the fuel cell 20 according to the SOC of the power storage device 51. The fuel cell power supply device 10 capable of executing such power generation control can be used, for example, as a normal power supply to the load 101. The fuel cell power supply device 10 may be installed in a certain area, or may be movable, and even portable.

[0056] Incidentally, in the present embodiment, a commercial power supply 100 is connected to a load 101, and power is also supplied from the commercial power supply 100 to the load 101. In such a configuration, for example, when the required power P1 is greater than the power that can be supplied by the commercial power supply 100, power is supplied from the power storage device 51 of the fuel cell power generation device 10 to the load 101. That is, when the commercial power supply 100 is connected to the load 101, the fuel cell power generation device 10 is used as an auxiliary power supply for the commercial power supply 100.

[0057] <Regarding the case where the command circuit 72 is connected to the circuit connection portion 71> Next, with reference to FIGS. 3 and 4, the case where the command circuit 72 is connected to the circuit connection portion 71 will be described. First, an example of the configuration of the command circuit 72 connected to the circuit connection portion 71 will be described.

[0058] <Command circuit 72> As shown in FIG. 3, the command circuit 72 includes a processing unit and a storage unit. The command circuit 72 may include dedicated hardware for executing at least some of various processes, for example, an application specific integrated circuit (ASIC). The command circuit 72 can be configured as a circuit including one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as an ASIC, or a combination thereof. In the present embodiment, the command circuit 72 is connected to the circuit connection portion 71. The command circuit 72 is separate from the power generation control circuit 70.

[0059] The command circuit 72 is connected to the circuit connection part 71. When the command circuit 72 is connected to the circuit connection part 71, the command circuit 72 is configured to be able to acquire the required power P1 of the load 101 via the circuit connection part 71. Also, the command circuit 72 is configured to be able to acquire the DC voltage Vdc1 of the commercial power supply 100 via the circuit connection part 71. The DC voltage Vdc1 reflects the state of power supply from the commercial power supply 100 to the load 101. Therefore, when connected to the circuit connection part 71, the command circuit 72 of the present embodiment monitors the power supply from the commercial power supply 100 to the load 101 using the DC voltage Vdc1. Note that the parameter used for power supply is not limited to the DC voltage Vdc1, and any parameter representing the operation of the commercial power supply 100 such as the power output from the commercial power supply 100 is acceptable.

[0060] When the command circuit 72 is connected to the circuit connection part 71, it is configured to transmit various commands to the power generation control circuit 70. The power generation control circuit 70 performs power generation control of the fuel cell 20 based on the command. The command includes a start command C1, a power generation command C2, and a stop command C3.

[0061] <Start command C1> The start command C1 is a signal used for starting the fuel cell 20. When the power generation control circuit 70 receives the start command C1, the power generation control circuit 70 starts the fuel cell 20. Therefore, the power generation control circuit 70 starts the fuel cell 20 based on the input of the start command C1 from the command circuit 72 in a situation where the command circuit 72 is connected to the circuit connection part 71.

[0062] <Power generation command C2> The power generation command C2 is a signal used for the power generation of the fuel cell 20. The power generation command C2 is a signal in the form of a power storage parameter of the power storage device 51, and in this embodiment, it is a signal in the SOC format. The signal in the SOC format is the same format as the SOC that the power generation control circuit 70 acquires from the power storage device 51. In other words, the power generation command C2 is a signal that can be substituted for the SOC that the power generation control circuit 70 acquires from the power storage device 51. The power generation command C2 is not limited to the SOC format, and any power storage parameter corresponding to the SOC is acceptable, such as the open-circuit voltage or closed-circuit voltage between terminals such as the open-circuit voltage or closed-circuit voltage of the power storage device 51, output power, output current, etc.

[0063] When the command circuit 72 is connected to the circuit connection portion 71, the power generation control circuit 70 performs power generation control of the fuel cell 20 based on the power generation command C2 from the command circuit 72. At this time, the command circuit 72 controls the power generation control circuit 70 by transmitting a signal in the SOC format of the power storage device 51 to the power generation control circuit 70 as the power generation command C2. For example, when the power generation control circuit 70 receives the power generation command C2, it performs power generation control to control the power generation amount of the fuel cell 20 based on the power generation command C2 instead of the SOC from the power storage device 51.

[0064] <Stop command C3> The stop command C3 is a command used to stop the fuel cell 20. When the power generation control circuit 70 receives the stop command C3, the power generation control circuit 70 stops the power generation of the fuel cell 20. The format of the stop command C3 is arbitrary.

[0065] <Emergency power supply processing> In this embodiment, the power generation control circuit 70 and the command circuit 72 function the fuel cell power supply device 10 as an emergency power supply device by executing emergency power supply processing. The fuel cell power supply device 10 as an emergency power supply device supplies the power of the fuel cell 20 to the commercial power supply 100 when the commercial power supply 100 experiences a power outage.

[0066] Next, the emergency power supply process performed by the power generation control circuit 70 and the command circuit 72 of the present embodiment will be described. In the present embodiment, the power storage device 51 is connected to the power storage connection unit 50. Accordingly, when performing the emergency power supply process, the changeover switch 62 is operated so that the connection switch 60 is ON and in the first connection state.

[0067] <Step S11> As shown in FIG. 4, in step S11, the command circuit 72 determines whether a power failure has occurred in the commercial power supply 100. The specific mode of this determination is arbitrary. For example, the command circuit 72 acquires the DC voltage Vdc1 from the voltage sensor 102 and determines whether the DC voltage Vdc1 is less than a predetermined power failure determination voltage V1. The power failure determination voltage V1 is, for example, the minimum operating voltage of the commercial power supply 100. Note that the power failure determination voltage V1 may be appropriately set according to the specifications of the commercial power supply 100 and the load 101. If the acquired DC voltage Vdc1 is less than the power failure determination voltage V1, the command circuit 72 determines that a power failure has occurred in the commercial power supply 100. In this case, the determination result of step S11 is affirmative. On the other hand, if the acquired DC voltage Vdc1 is equal to or greater than the power failure determination voltage V1, the command circuit 72 determines that no power failure has occurred in the commercial power supply 100. In this case, the determination result of step S11 is negative. If the determination result of step S11 is negative, the command circuit 72 ends the emergency power supply process.

[0068] <Step S12> On the other hand, if the determination result of step S11 is affirmative, the process proceeds to step S12, and the command circuit 72 transmits a start command C1 to the power generation control circuit 70 based on the occurrence of a power failure in the commercial power supply 100. Note that the format of the start command C1 is arbitrary. For example, it is in the SOC format of the power storage device 51 similar to the power generation command C2.

[0069] <Step S13> When the power generation control circuit 70 receives the start command C1 from the command circuit 72, the process proceeds to step S13, and the power generation control circuit 70 starts the fuel cell 20.

[0070] <Step S14> Next, proceed to step S14, and the command circuit 72 acquires the required power P1 from the load 101.

[0071] <Step S15> Next, proceed to step S15, and the command circuit 72 transmits a power generation command C2 to the power generation control circuit 70 based on the required power P1 acquired in step S14. At this time, the command circuit 72 converts the required power P1 in the SOC format to the power generation command C2. The specific mode of this conversion is arbitrary. For example, the command circuit 72 refers to a map showing the correspondence between the required power P1 and the power generation command C2 to convert the required power P1 to the power generation command C2. The map is stored, for example, in the storage unit of the command circuit 72. As the required power P1 increases, the SOC represented by the power generation command C2 decreases.

[0072] <Step S16> When the power generation control circuit 70 receives the power generation command C2, proceed to step S16, and the power generation control circuit 70 performs power generation control of the fuel cell 20 based on the SOC represented by the received power generation command C2. The specific mode of power generation control is the same as the process of step S2 in the power generation process. That is, the power generation control circuit 70 controls the power generation amount of the fuel cell 20 according to the SOC represented by the power generation command C2. As power generation control, when the SOC of the power storage device 51 falls below a certain value, the power generation control circuit 70 performs multi-stage power generation that increases the power generation amount of the fuel cell 20 every time the SOC of the power storage device 51 falls below the certain value. When the power generation control circuit 70 acquires both the SOC of the power storage device 51 from the BMS 54 and the SOC represented by the power generation command C2 from the command circuit 72, the power generation control circuit 70 performs power generation control based on the SOC represented by the power generation command C2 with priority over the SOC of the power storage device 51.

[0073] The power generated by the fuel cell 20 is converted by the power converter 30 into a DC voltage comparable to the voltage of the power storage device 51 and then supplied to the commercial power supply 100. Note that a predetermined period is required from when the power failure occurrence determination is made in step S11 until the power generated by the fuel cell 20 is supplied to the load 101. The predetermined period is, for example, the period from the start of the fuel cell 20 in step S12 until the output voltage of the power converter 30 stabilizes. During this period, the output voltage from the power converter 30 is smaller than the output voltage of the power storage device 51. Therefore, the output voltage of the power storage device 51 is applied to the load 101 via the output terminal portion 40. As a result, the voltage drop from when the commercial power supply 100 experiences a power failure until the fuel cell 20 starts generating power is suppressed. Along with this, the power of the power storage device 51 is supplied to the load 101. Therefore, the power storage device 51 takes on the responsibility of supplying power to the load 101 in place of the fuel cell 20 and the commercial power supply 100.

[0074] <Step S17> After that, proceeding to step S17, the command circuit 72 determines whether the commercial power supply 100 has been restored. The specific mode of this determination is arbitrary. For example, the command circuit 72 acquires the DC voltage Vdc1 from the voltage sensor 102 and determines whether the DC voltage Vdc1 is equal to or higher than a predetermined power restoration determination voltage V2. The power restoration determination voltage V2 is, for example, the minimum operating voltage of the commercial power supply 100. Note that the power restoration determination voltage V2 may be appropriately set according to the specifications of the commercial power supply 100 and the load 101. When the acquired DC voltage Vdc1 is equal to or higher than the power restoration determination voltage V2, the command circuit 72 determines that the commercial power supply 100 has been restored. In this case, the determination result of step S17 is affirmative. On the other hand, when the acquired DC voltage Vdc1 is less than the power restoration determination voltage V2, the command circuit 72 determines that the commercial power supply 100 has not been restored. In this case, the determination result of step S17 is negative. When the determination result of step S17 is negative, it returns to step S14, and the power generation control circuit 70 acquires the required power P1 again.

[0075] <Step S18> On one hand, when the determination result in step S17 is affirmative, that is, when it is determined that the commercial power supply 100 has been restored, the process proceeds to step S18, and the command circuit 72 transmits a stop command C3 to the power generation control circuit 70 via the circuit connection part 71.

[0076] <Step S19> When the power generation control circuit 70 receives the stop command C3, the process proceeds to step S19, and the power generation control circuit 70 stops the power generation of the fuel cell 20. After that, the command circuit 72 ends the emergency power supply process.

[0077] <Operation of the First Embodiment> When the command circuit 72 is not connected to the circuit connection part 71, the power generation control circuit 70 can function as an auxiliary power supply that supplies power from the fuel cell power supply device 10 to the load 101 by performing the power generation process.

[0078] On the other hand, when the command circuit 72 is connected to the circuit connection part 71, the power generation control circuit 70 performs the emergency power supply process. In the emergency power supply process, the power generation control circuit 70 performs the power generation control of the fuel cell 20 based on the power generation command C2 transmitted from the command circuit 72 triggered by the power outage of the commercial power supply 100. Thereby, it becomes possible for the fuel cell power supply device 10 to function as an emergency power supply.

[0079] <Effect of the First Embodiment> Hereinafter, the effect of the first embodiment will be described. (1-1) The fuel cell power supply device 10 includes a fuel cell 20, an output terminal part 40 used to output the power of the fuel cell 20 to the load 101, a power generation control circuit 70 that performs the power generation control of the fuel cell 20, and a circuit connection part 71 that is connected to the power generation control circuit 70 and is used to connect to the circuit connection part 71.

[0080] In such a configuration, the command circuit 72 is configured to transmit a power generation command C2 to the power generation control circuit 70 when the circuit connection unit 71 is connected to the circuit connection unit 71. The power generation control circuit 70 performs power generation control of the fuel cell 20 based on the power generation command C2 from the command circuit 72 when the command circuit 72 is connected to the circuit connection unit 71.

[0081] According to such a configuration, by connecting the command circuit 72, the command circuit 72 can perform power generation control of the fuel cell 20 via the power generation control circuit 70. Thereby, power generation control of the fuel cell 20 can be performed using the command circuit 72. Therefore, when it is not necessary to perform power generation control of the fuel cell 20 using the command circuit 72, for example, when the power storage device 51 is connected to the power storage connection unit 50, the command circuit 72 is not connected to the circuit connection unit 71, while when it is desired to perform power generation control of the fuel cell 20 using the command circuit 72, for example, when the fuel cell power supply device 10 is used as an emergency power supply, the command circuit 72 may be connected to the circuit connection unit 71. Thus, even when the usage conditions differ between the case of using the command circuit 72 and the case of not using it, the same fuel cell power supply device 10 can be used. Therefore, the versatility of the fuel cell power supply device 10 can be improved.

[0082] (1-2) The command circuit 72 monitors the power supply from the commercial power supply 100 to the load 101 when connected to the circuit connection unit 71. The command circuit 72 is configured to transmit a start command C1 to the power generation control circuit 70 by executing the process of step S12 based on the result of the determination in step S11 that a power failure has occurred in the commercial power supply 100.

[0083] In such a configuration, the power generation control circuit 70 starts the fuel cell 20 by executing the process of step S13 based on the fact that a power generation command C2 is input from the circuit connection unit 71 in a situation where the command circuit 72 is connected to the circuit connection unit 71.

[0084] According to such a configuration, by connecting the command circuit 72 to the circuit connection part 71, it is possible to detect a power failure of the commercial power supply 100. Further, when a power failure of the commercial power supply 100 occurs, the fuel cell 20 starts up, and thus the fuel cell 20 functions as a backup. Therefore, by connecting the command circuit 72, the fuel cell power supply device 10 can be used as an emergency power supply. Thus, further improvement in versatility can be achieved.

[0085] (1-3) The fuel cell power supply device 10 is connected to the output terminal part 40 and includes a power storage connection part 50 used for connecting the power storage device 51. In such a configuration, the power generation control circuit 70 performs power generation control of the fuel cell power supply device 10 based on power storage parameters corresponding to the SOC of the power storage device 51. Further, the command circuit 72 controls the power generation control circuit 70 by transmitting a signal in the form of the power storage parameters of the power storage device 51 to the power generation control circuit 70 as a power generation command C2.

[0086] According to such a configuration, when the power storage device 51 is connected to the power storage connection part 50, a voltage can be applied from the power storage device 51 to the load 101 via the output terminal part 40. Therefore, it is possible to suppress a voltage drop from when the commercial power supply 100 fails until the fuel cell 20 starts generating power.

[0087] Also, according to such a configuration, by connecting the power storage device 51 to the power storage connection part 50, the power of the power storage device 51 can be supplied to the load 101. Here, if power is being supplied from the power storage device 51 to the load 101, the SOC of the power storage device 51 decreases. On the other hand, if power is not being supplied from the power storage device 51 to the load 101, the SOC of the power storage device 51 does not decrease. For this reason, the SOC of the power storage device 51 can vary according to the mode of power supply from the power storage device 51 to the load 101.

[0088] In this regard, according to the present configuration, by performing power generation control based on the power storage parameter corresponding to the SOC of the power storage device 51 by the power generation control circuit 70, it is possible to supply the necessary power to the load 101 without the load 101 and the power generation control circuit 70 directly exchanging information.

[0089] On the other hand, when the command circuit 72 is connected to the circuit connection part 71, the power generation control circuit 70 may perform power generation control based on the power generation command C2 from the command circuit 72. In this case, when a signal in a dedicated format is input from the command circuit 72 to the power generation control circuit 70, it may be necessary to configure the power generation control circuit 70 to be able to perform power generation control based on the signal in the dedicated format.

[0090] In this regard, according to the present configuration, the command circuit 72 is configured to transmit a signal in the form of a power storage parameter of the power storage device 51 as the power generation command C2. Thereby, it is possible to respond to the power generation command C2 from the command circuit 72 by using the power generation control circuit 70 that performs power generation control based on the power storage parameter of the power storage device 51. That is, the common power generation control circuit 70 can be used whether the command circuit 72 is connected or not. Therefore, since it is not necessary to separately prepare a power generation control circuit 70 for responding to the power generation command C2 from the command circuit 72, it is possible to improve the versatility.

[0091] (1-5) The fuel cell power supply device 10 includes a connection switch 60 that can be switched between ON and OFF. In such a configuration, the power storage connection part 50 is connected to the fuel cell 20 via the connection switch 60.

[0092] According to such a configuration, by turning off the connection switch 60, the connection between the fuel cell 20 and the power storage connection part 50 can be interrupted. Thereby, when attaching and detaching the power storage device 51 to the power storage connection part 50, it is possible to suppress the power of the fuel cell 20 from being transmitted through an unexpected path via the power storage connection part 50. Therefore, the safety of the fuel cell power supply device 10 can be improved.

[0093] (1-6) The fuel cell power supply device 10 includes a changeover switch 62 provided between the fuel cell 20 and the output terminal section 40 and capable of switching between a first connection state and a second connection state. The connection switch 60 is connected to the output terminal section 40 via the changeover switch 62.

[0094] In such a configuration, in the first connection state, the power storage connection section 50 is connected to the output terminal section 40 via the connection switch 60 and the changeover switch 62. Further, in the second connection state, the power storage connection section 50 is connected to the output terminal section 40 via the changeover switch 62 without passing through the connection switch 60.

[0095] According to such a configuration, in the first connection state, by turning off the connection switch 60, the connection between the power storage connection section 50 and the output terminal section 40 can be interrupted. Thereby, when the power storage device 51 is connected to the power storage connection section 50, it is possible to switch whether to output the power of the power storage device 51 from the output terminal section 40 by operating the connection switch 60. Therefore, when attaching and detaching the power storage device 51 to and from the power storage connection section 50, it is possible to suppress the power of the power storage device 51 from being transmitted through an unexpected path via the output terminal section 40.

[0096] Also, in the second connection state, by turning off the connection switch 60, the connection between the output terminal section 40 and the fuel cell 20 can be interrupted. Thereby, for example, even when the load 101 includes a battery, it is possible to stop the power of the battery included in the load 101 from being transmitted to the fuel cell 20 by operating the connection switch 60. Therefore, for example, when performing maintenance or the like on the fuel cell 20, it is possible to suppress the output of the load 101 from being transmitted through an unexpected path via the output terminal section 40.

[0097] As described above, it is possible to provide the fuel cell power supply device 10 that can achieve both an improvement in safety and an improvement in versatility capable of coping with various loads 101. <Configuration of the Second Embodiment> Next, the fuel cell power supply device of the second embodiment will be described. Regarding the configuration similar to that of the first embodiment, the description will be omitted by assigning the same member numbers.

[0098] As shown in FIG. 5, the fuel cell power supply device 10 further includes a communication connection part 80. The communication connection part 80 is used to connect to other fuel cell power supply devices 10. The communication connection part 80 is connected to the power generation control circuit 70. The communication connection part 80 is configured such that a communication signal line 81 can be connected. The communication signal line 81 is connected to the communication connection parts 80 of a plurality of fuel cell power supply devices 10. In FIG. 5, the illustration of the connection switch 60, the fuse 61, and the changeover switch 62 is omitted.

[0099] When the command circuit 72 is connected to the circuit connection part 71, the commands C1, C2, C3 of the command circuit 72 are transmitted to the communication connection part 80 via the power generation control circuit 70. The commands C1, C2, C3 transmitted to the communication connection part 80 are transmitted to other fuel cell power supply devices 10 via the communication signal line 81.

[0100] The specific form of the communication connection part 80 can be arbitrary, such as a connector or a port. Also, the specific form of the communication signal line 81 can be arbitrary, such as a cable. When the communication connection part 80 is configured to be capable of wireless communication, the communication signal line 81 may be omitted.

[0101] <Fuel cell power supply system 200> Next, the fuel cell power supply system 200 using the fuel cell power supply device 10 of the second embodiment will be described.

[0102] As shown in FIG. 5, the fuel cell power supply system 200 includes a plurality of fuel cell power supply devices 10 and a communication signal line 81 that connects the plurality of fuel cell power supply devices 10 to each other. The plurality of fuel cell power supply devices 10 are composed of at least one main fuel cell power supply device 10a and at least one sub - fuel cell power supply device 10b.

[0103] The main fuel cell power supply device 10a is a fuel cell power supply device 10 in which a command circuit 72 is connected to a circuit connection part 71. In the present embodiment, the number of main fuel cell power supply devices 10a is one.

[0104] The sub fuel cell power supply device 10b is a fuel cell power supply device 10 in which a command circuit 72 is not connected to a circuit connection part 71. In the present embodiment, the number of sub fuel cell power supply devices 10b is two or more.

[0105] In the present embodiment, a power storage device 51 is connected to the power storage connection part 50 of each of the fuel cell power supply devices 10a and 10b. That is, each of the fuel cell power supply devices 10a and 10b has a power storage device 51. However, it is not limited thereto. As long as the power storage device 51 is connected to the power storage connection part 50 of the main fuel cell power supply device 10a, the power storage device 51 may not be connected to the power storage connection part 50 of the sub fuel cell power supply device 10b. That is, the sub fuel cell power supply device 10b may not have a power storage device 51. Further, as long as the power storage device 51 is connected to the power storage connection part 50 of at least one of the sub fuel cell power supply devices 10b, the power storage device 51 may not be connected to the power storage connection part 50 of the main fuel cell power supply device 10a. That is, the main fuel cell power supply device 10a may not have a power storage device 51. In short, at least one of the fuel cell power supply devices 10a and 10b constituting the fuel cell power supply system 200 may have a power storage device 51.

[0106] The output terminal parts 40 of each of the fuel cell power supply devices 10a and 10b are connected in parallel to the load 101. Thereby, it becomes possible to supply power from each of the plurality of fuel cell power supply devices 10a and 10b to the load 101.

[0107] The communication connection part 80 of each sub fuel cell power supply device 10b is connected to the communication connection part 80 of the main fuel cell power supply device 10a via the communication signal line 81. The communication connection part 80 of some sub fuel cell power supply devices 10b is connected to the communication connection part 80 of other sub fuel cell power supply devices 10b. And the communication connection part 80 of the said some sub fuel cell power supply devices 10b is connected to the communication connection part 80 of the main fuel cell power supply device 10a via the communication connection part 80 of the said other sub fuel cell power supply devices 10b. That is, each sub fuel cell power supply device 10b is connected to the main fuel cell power supply device 10a via the communication signal line 81, or via the communication signal line 81 and other sub fuel cell power supply devices 10b.

[0108] In this embodiment, the fuel cell power supply devices 10a and 10b constituting the fuel cell power supply system 200 are connected in series via the communication signal line 81. In other words, one or two fuel cell power supply devices 10a and 10b are connected to a certain fuel cell power supply device 10a and 10b constituting the fuel cell power supply system 200. Thereby, communication between the command circuit 72 of the main fuel cell power supply device 10a and each power generation control circuit 70 becomes possible. The specific mode of the said communication is arbitrary, for example, those conforming to a predetermined communication standard such as CAN: Controlled Area Network or LIN: Local Interconnected Network etc. may be mentioned.

[0109] The command circuit 72 of the main fuel cell power supply device 10a transmits commands C1, C2, and C3 to the power generation control circuit 70 of the main fuel cell power supply device 10a. At this time, the commands C1, C2, and C3 of the command circuit 72 are transmitted to the power generation control circuit 70 of each sub fuel cell power supply device 10b via the power generation control circuit 70, the communication connection part 80, and the communication signal line 81 of each fuel cell power supply device 10a and 10b. Thereby, the command circuit 72 can perform overall control of the power generation control circuit 70 of the sub fuel cell power supply device 10b. The command circuit 72 performs emergency power supply processing for the entire fuel cell power supply system 200 by overall controlling each power generation control circuit 70.

[0110] <Regarding Emergency Power Supply Processing for the Entire Fuel Cell Power System 200> Hereinafter, the emergency power supply processing performed for the entire fuel cell power system 200 will be described.

[0111] <Step S21> As shown in FIG. 6, first, in step S21, the command circuit 72 determines whether a power outage has occurred in the commercial power supply 100. The determination method is the same as the processing in step S11. If the determination result in step S21 is negative, the command circuit 72 ends the emergency power supply processing.

[0112] <Step S22> On the other hand, if the determination result in step S21 is positive, the process proceeds to step S22, and the command circuit 72 transmits a start command C1 to each of the power generation control circuits 70 of the plurality of fuel cell power supply devices 10a, 10b based on the occurrence of a power outage in the commercial power supply 100. The format of the start command C1 and the like are the same as in the case of step S12.

[0113] <Step S23> When each power generation control circuit 70 receives the start command C1 from the command circuit 72, the process proceeds to step S23, and the power generation control circuit 70 starts each fuel cell 20.

[0114] <Step S24> Next, the process proceeds to step S24, and the command circuit 72 acquires the required power P1 from the load 101.

[0115] <Step S25> Next, the process proceeds to step S25, and the command circuit 72 transmits a power generation command C2 to each power generation control circuit 70 based on the required power P1 acquired in step S14. The format of the power generation command C2 and the correspondence with the required power P1 are the same as in step S15.

[0116] Here, the command circuit 72 determines the power generation amount of each fuel cell 20 according to the required power P1, and transmits a power generation command C2 corresponding to the power generation amount to each power generation control circuit 70. At this time, the sum of the power generation amounts of each fuel cell 20 coincides with the required power P1. A method for determining the power generation amount of each fuel cell 20 will be exemplified. The command circuit 72 divides the required power P1 by a certain power value that can be output by the fuel cell 20. Such a power value includes, for example, the rated power of the fuel cell 20. Then, the power generation command C2 is transmitted to each power generation control circuit 70 so that the fuel cell 20 generates power at the rated power by the number of integers of the divided value. Alternatively, a power generation command C2 corresponding to the value obtained by dividing the required power P1 by the number of the fuel cell power supply devices 10a and 10b may be transmitted to each power generation control circuit 70.

[0117] <Step S26> When the power generation control circuit 70 receives the power generation command C2, it proceeds to step S26, and the power generation control circuit 70 performs power generation control of the fuel cell 20 based on the SOC represented by the received power generation command C2. The specific mode of power generation control is the same as that in step S16 or step S2.

[0118] Here, the power generation command C2 of the command circuit 72 of the main fuel cell power supply device 10a is input to the power generation control circuit 70 of the sub fuel cell power supply device 10b via the communication connection unit 80. Therefore, when the power generation command C2 of the command circuit 72 is input to the power generation control circuit 70 of the sub fuel cell power supply device 10b via the communication connection unit 80, the power generation control circuit 70 of the sub fuel cell power supply device 10b performs power generation control based on the power generation command C2.

[0119] <Step S27> Next, it proceeds to step S27, and the command circuit 72 determines whether the commercial power supply 100 has been restored. The specific mode of this determination is arbitrary, and for example, it is the same as that in step S17. If the determination result in step S27 is negative, it returns to step S24, and the power generation control circuit 70 acquires the required power P1 again.

[0120] <Step S28> On the other hand, if the determination result in step S27 is affirmative, that is, it is determined that the commercial power supply 100 has been restored, the process proceeds to step S28, and the command circuit 72 transmits a stop command C3 to each power generation control circuit 70.

[0121] <Step S29> When each power generation control circuit 70 receives the stop command C3, the process proceeds to step S29, and each power generation control circuit 70 stops the power generation of the fuel cell 20. Thereafter, the command circuit 72 ends the emergency power supply process.

[0122] <Operation of the Second Embodiment> When a power failure of the commercial power supply 100 occurs, the command circuit 72 performs an emergency power supply process for the entire fuel cell power supply system 200. In this emergency power supply process, the command circuit 72 transmits a power generation command C2 to each power generation control circuit 70 by executing the process of step S25. The power generation command C2 is transmitted not only to the power generation control circuit 70 of the main fuel cell power supply device 10a but also to the power generation control circuit 70 of the sub - fuel cell power supply device 10b via the communication connection unit 80 and the communication signal line 81. Each power generation control circuit 70 performs power generation control of the fuel cell 20 based on the power generation command C2 from the command circuit 72 of the main fuel cell power supply device 10a. The power generated by the fuel cell 20 is output to the load 101 respectively. Thereby, the power that can be output from the fuel cell power supply system 200 to the load 101 becomes larger than the power that can be output from one fuel cell power supply device 10 to the load 101. The fuel cell power supply system 200 can function as an emergency power supply capable of coping with a load 101 with a larger required power P1. At this time, the main fuel cell power supply device 10a functions as a master device for overall control of a plurality of sub - fuel cell power supply devices 10b.

[0123] <Effect of the Second Embodiment> Hereinafter, the effects of the second embodiment will be described. (2 - 1) The fuel cell power supply devices 10a and 10b are provided with a communication connection unit 80 used for connecting to other fuel cell power supply devices 10a and 10b.

[0124] In such a configuration, the power generation control circuit 70 is connected to the communication connection unit 80, and when the power generation command C2 of the command circuit 72 is input via the communication connection unit 80, power generation control is performed based on the power generation command C2.

[0125] According to such a configuration, by connecting and using a plurality of fuel cell power supply devices 10 to each other, it is possible to output a large amount of power that cannot be output by a single fuel cell power supply device 10. As a result, without separately designing a fuel cell power supply device 10 for large power, it is possible to meet the usage conditions of large power, so that the versatility can be further improved.

[0126] Here, when a plurality of fuel cell power supply devices 10 are used, it is conceivable that the command circuit 72 controls each fuel cell power supply device 10 in an integrated manner. In this case, since the power generation control circuit 70 performs power generation control of the fuel cell 20 based on the power generation command C2 input via the communication connection unit 80, the command circuit 72 only needs to transmit the power generation command C2 to the communication connection unit 80. Therefore, the command circuit 72 only needs to be provided in at least one of the plurality of fuel cell power supply devices 10. Thus, the configuration can be simplified.

[0127] Also, by connecting the command circuit 72 capable of performing overall control to the circuit connection unit 71, the fuel cell power supply device 10 can be used as a master device that performs overall control of a plurality of fuel cell power supply devices 10. Thereby, the versatility can be improved.

[0128] <Configuration of the Third Embodiment> Next, a third embodiment of the fuel cell power supply device and the fuel cell power supply system will be described. Regarding the configurations similar to those of the first and second embodiments, the same member numbers will be assigned and the description will be omitted.

[0129] As shown in FIG. 7, similar to the second embodiment, the fuel cell power supply system 200 of the third embodiment includes at least one main fuel cell power supply device 10a, at least one sub fuel cell power supply device 10b, and a communication signal line 81. In FIG. 7, the connection switch 60, the fuse 61, and the changeover switch 62 are not shown.

[0130] Similar to the second embodiment, the fuel cell power supply devices 10a and 10b of the third embodiment each include a communication connection portion 80. The communication connection portions 80 of the respective fuel cell power supply devices 10a and 10b are connected to each other via the communication signal line 81.

[0131] In the present embodiment, a power storage device 51 is connected to the power storage connection portion 50 of each of the fuel cell power supply devices 10a and 10b. That is, each of the fuel cell power supply devices 10a and 10b has a power storage device 51. However, the present invention is not limited to this, and the power storage device 51 may not be connected to the power storage connection portion 50 of the sub fuel cell power supply device 10b. That is, the sub fuel cell power supply device 10b may not have a power storage device 51. Further, if the power storage device 51 is connected to the power storage connection portion 50 of at least one sub fuel cell power supply device 10b, the power storage device 51 may not be connected to the power storage connection portion 50 of the main fuel cell power supply device 10a. Furthermore, when a voltage source such as a storage battery 52 is provided outside the fuel cell power supply system 200, for example, between the output terminal portions 40 of the respective fuel cell power supply devices 10a and 10b and the load 101, the power storage device 51 may not be connected to the power storage connection portion 50 of all the fuel cell power supply devices 10a and 10b. That is, in this case, the fuel cell power supply system 200 may not include the power storage device 51.

[0132] On the other hand, the third embodiment is different from the second embodiment in that the commercial power supply 100 is not connected to the load 101. In the third embodiment, the command circuit 72 performs a system power generation process, and outputs power corresponding to the required power P1 to the load 101 as the entire fuel cell power supply system 200.

[0133] <System power generation process> An example of system power generation processing will be described below. As shown in FIG. 8, first, in step S31, the command circuit 72 acquires the required power P1 from the load 101. The acquisition mode is the same as that in step S14.

[0134] Next, proceeding to step S32, the command circuit 72 transmits a power generation command C2 to each power generation control circuit 70 based on the required power P1 acquired in step S31. The format of the power generation command C2 and the correspondence with the required power P1 are the same as those in step S15. Also, the method of determining each fuel cell 20 according to the required power P1 is the same as that described in step S25.

[0135] When each power generation control circuit 70 receives the power generation command C2 from the command circuit 72, it proceeds to step S33, and each power generation control circuit 70 performs power generation control of each fuel cell 20 based on the power generation command C2. Thereafter, the command circuit 72 ends the power generation process. The command circuit 72 continuously outputs power to the load 101 by continuously performing the power generation process.

[0136] In this way, the fuel cell power supply device 10 and the fuel cell power system 200 of the third embodiment function as a power supply device that supplies power to the load 101 according to the required power P1 regardless of the occurrence of a power outage in the commercial power supply 100.

[0137] <Actions and Effects of the Third Embodiment> (3-1) When the load 101 is not connected to the commercial power supply 100, the command circuit 72 performs system power generation processing to output power from the fuel cell power system 200 to the load 101 based on the acquired required power P1. Thereby, by connecting the command circuit 72 to the circuit connection part 71, the command circuit 72 can function as a power supply device that outputs power from the fuel cell power system 200 including the fuel cell power supply devices 10a and 10b to the load 101 instead of the commercial power supply 100. Therefore, since it is possible to output power to the load 101 that is not connected to the commercial power supply 100, further improvement in versatility can be achieved.

[0138] <Modification Example> The embodiment can be implemented with the following modifications. The embodiment and the following modification examples can be implemented in combination with each other as long as they do not technically conflict with each other.

[0139] · As shown in FIG. 9, the fuel cell power supply device 10 may be used under the condition that the commercial power supply 100 is not connected to the load 101. In this case, the power generation control circuit 70 performs the power generation process shown in steps S1 and S2, so that the fuel cell 20 supplies power to the load 101 together with the power storage device 51. That is, the fuel cell power supply device 10 is not limited to the configuration used as an auxiliary power supply, and may be used as a main power supply in normal use.

[0140] · As shown in FIG. 10, in the first embodiment, when a power storage device such as a storage battery 52 is provided on the load 101 side with respect to the output terminal portion 40, for example, when the storage battery 52 is connected in parallel between the output terminal portion 40 and the load 101, the power storage device 51 may not be connected to the power storage connection portion 50. At this time, the command circuit 72 is connected to the circuit connection portion 71, and the command circuit 72 transmits commands C1, C2, and C3 to the power generation control circuit 70 to control the power generation control circuit 70.

[0141] In this way, by providing the fuel cell power supply device 10 with the power storage connection portion 50, the presence or absence of the power storage device 51 can be selected according to the mode of the load 101. Thereby, the further versatility of the fuel cell power supply device 10 can be improved.

[0142] Note that when the power storage device 51 is not connected to the power storage connection portion 50, the connection switch 60 is turned on, and the changeover switch 62 is operated so as to be in the second connection state. Thereby, since the fuel cell 20 and the load 101 are connected via the fuse 61, even if an overcurrent occurs from the fuel cell 20 toward the output terminal portion 40, it is possible to suppress the continuous flow of the overcurrent.

[0143] · In the first and second embodiments, the command of the command circuit 72 is arbitrary as long as it includes the power generation command C2, and does not have to include the start command C1 and the stop command C3. In this case, the power generation control circuit 70 may perform the process of step S13 upon receiving the power generation command C2. Similarly, the power generation control circuit 70 may perform the process of step S19 upon the stop of receiving the power generation command C2.

[0144] · In the second and third embodiments, the command circuit 72 of the main fuel cell power supply device 10a may be configured to be capable of wireless communication with each power generation control circuit 70. The command circuit 72 transmits the commands C1, C2, and C3 to other power generation control circuits 70 through wireless communication. In this case, the fuel cell power supply system 200 does not have to include the communication signal line 81.

[0145] · In the first embodiment, the fuel cell power supply device 10 does not have to have the power storage device 51. In this case, it is preferable that the command circuit 72 is connected to the circuit connection portion 71. In this case, when the commercial power supply 100 is connected to the load 101, the fuel cell power supply device 10 may be used as an auxiliary power supply or an emergency power supply of the commercial power supply 100. Also, when the commercial power supply 100 is not connected to the load 101, the fuel cell power supply device 10 may be used as a normal main power supply to the load 101. Accordingly, the fuel cell power supply device 10 does not have to include the power storage connection portion 50.

[0146] · In the second embodiment, the fuel cell power supply system 200 may include a plurality of main fuel cell power supply devices 10a. In this case, the fuel cell power supply system 200 may perform the emergency power supply process using the command circuit 72 of any one of the main fuel cell power supply devices 10a and the power generation control circuits 70 of each fuel cell power supply device 10a, 10b.

[0147] Similarly in the third embodiment, the fuel cell power supply system 200 may include a plurality of main fuel cell power supply devices 10a. In this case, the fuel cell power supply system 200 may perform system power generation processing using a command circuit 72 of any one of the main fuel cell power supply devices 10a and a power generation control circuit 70 of each main fuel cell power supply device 10a.

[0148] · In the second embodiment, the power storage devices 51 of all the fuel cell power supply devices 10a and 10b including the main fuel cell power supply device 10a and the sub fuel cell power supply device 10b may be omitted. However, when the fuel cell power supply devices 10a and 10b are used as emergency power supplies, it is preferable to have at least one power storage device 51 in view of suppressing a decrease in the DC voltage Vdc1 due to a power failure of the commercial power supply 100. When a power storage device such as a storage battery 52 is provided on the load 101 side with respect to the output terminal portions 40 of the fuel cell power supply devices 10a and 10b, the power storage device can suppress the decrease in the DC voltage Vdc1. Particularly in such a case, none of the fuel cell power supply devices 10a and 10b need to have the power storage device 51.

[0149] · In the third embodiment, the power storage devices 51 of all the fuel cell power supply devices 10a and 10b including the main fuel cell power supply device 10a and the sub fuel cell power supply device 10b may be omitted. However, when the fuel cell power supply devices 10a and 10b are used as a normal power supply, at least one of the fuel cell power supply devices 10a and 10b having the power storage device 51 can stabilize the power supply to the load 101. Further, thereby, it becomes possible to charge the surplus power from the fuel cell power system 200 to the load 101 into the power storage device 51. When a power storage device such as a storage battery 52 is provided on the load 101 side with respect to the output terminal portion 40 of each fuel cell power supply device 10a and 10b, the power storage device can suppress the decrease in the DC voltage Vdc1. Particularly in such a case, any of the fuel cell power supply devices 10a and 10b may not have the power storage device 51. In short, in the second and third embodiments, the fuel cell power system 200 may not have the power storage device 51 as a whole. Along with this, the fuel cell power supply devices 10a and 10b constituting the fuel cell power system 200 may not have the power storage connection portions 50, respectively.

[0150] · In each embodiment, the connection switch 60, the fuse 61, and the changeover switch 62 may not be provided, respectively. · In each embodiment, the power storage device 51 may not be configured to be detachable from the power storage connection portion 50, and may be fixed to the power storage connection portion 50.

[0151] · In each embodiment, the power converter 30 may not be provided.

Explanation of Reference Numerals

[0152] 10... Fuel cell power supply device, 20... Fuel cell, 40... Output terminal portion, 50... Power storage connection portion, 51... Power storage device, 60... Connection switch, 62... Changeover switch, 70... Power generation control circuit, 71... Circuit connection portion, 72... Command circuit, 80... Communication connection portion, 100... Commercial power supply, 101... Load, C1... Start command, C2... Power generation command.

Claims

1. A fuel cell, an output terminal unit used to output the power of the fuel cell to a load, a power generation control circuit that performs power generation control of the fuel cell, A fuel cell power supply device comprising a circuit connection part connected to the power generation control circuit and to which a command circuit is detachably connected, The power generation control circuit performs the power generation control of the fuel cell in any of a mode in which the command circuit is connected to the circuit connection part and a mode in which the command circuit is not connected to the circuit connection part, The command circuit is configured to transmit a power generation command to the power generation control circuit when connected to the circuit connection part, The power generation control circuit gives priority to the power generation command from the command circuit when performing the power generation control of the fuel cell when the command circuit is connected to the circuit connection part. A fuel cell power supply device.

2. The circuit connection part is a connector to which the command circuit is detachable. The fuel cell power supply device according to Claim 1.

3. The command circuit monitors the power supply from the commercial power supply to the load when connected to the circuit connection part, and is configured to transmit a start command to the power generation control circuit based on the occurrence of a power outage in the commercial power supply, The power generation control circuit starts the fuel cell based on the input of the start command from the command circuit in a situation where the command circuit is connected to the circuit connection part. The fuel cell power supply device according to Claim 1 or 2.

4. The fuel cell power supply device according to Claim 3, further comprising a power storage connection part that is connected to the output terminal unit and is used to connect a power storage device.

5. A power storage connection part that is connected to the output terminal unit and is used to connect a power storage device is provided, The power generation control circuit performs the power generation control of the fuel cell based on power storage parameters corresponding to the SOC of the power storage device, The command circuit controls the power generation control circuit by transmitting a signal in the form of the power storage parameters of the power storage device as the power generation command to the power generation control circuit. The fuel cell power supply device according to any one of Claims 1 to 3. **Claim 6**: The power generation control circuit, as the power generation control, when the SOC of the power storage device falls below a predetermined value, performs multi-stage power generation that increases the power generation amount of the fuel cell every time the SOC of the power storage device falls below the predetermined value. The fuel cell power supply device according to claim 5. **Claim 7** Comprising a communication connection part used for connecting to other fuel cell power supply devices, The power generation control circuit is connected to the communication connection part, and when the power generation command of the command circuit is input via the communication connection part, the power generation control is performed based on the power generation command. The fuel cell power supply device according to any one of claims 1 to 6. **Claim 8** Comprising a connection switch capable of switching ON / OFF, The power storage connection part is connected to the fuel cell via the connection switch. The fuel cell power supply device according to claim 4 or 5. **Claim 9** Comprising a changeover switch provided between the fuel cell and the output terminal part and capable of switching between a first connection state and a second connection state, In the first connection state, the power storage connection part is connected to the output terminal part via the connection switch and the changeover switch, In the second connection state, the power storage connection part is connected to the output terminal part via the changeover switch without passing through the connection switch. The fuel cell power supply device according to claim 8. **Claim 10**: A fuel cell power supply system configured by connecting a plurality of fuel cell power supply devices to each other, The fuel cell power supply device includes A fuel cell, An output terminal part used to output the power of the fuel cell to a load, A power generation control circuit that performs power generation control of the fuel cell, A circuit connection part connected to the power generation control circuit and to which a command circuit is detachably connected, A communication connection part used for connecting to other fuel cell power supply devices, The power generation control circuit performs the power generation control of the fuel cell in either a mode where the command circuit is connected to the circuit connection part or a mode where the command circuit is not connected to the circuit connection part, The command circuit is connected to at least one of the circuit connection parts of the fuel cell power supply devices constituting the fuel cell power supply system, When the command circuit is connected to the circuit connection part, it is configured to determine the power generation amount of each fuel cell constituting the fuel cell power supply system according to the required power of the load and transmit a power generation command corresponding to the power generation amount to the power generation control circuit. When the fuel cell power supply device in which the command circuit is connected to the circuit connection part is used as the main fuel cell power supply device, and one or more of the fuel cell power supply devices connected to the main fuel cell power supply device via the communication connection part are used as sub-fuel cell power supply devices, When the power generation command of the command circuit is input to the power generation control circuit of the main fuel cell power supply device, the power generation command is transmitted to the power generation control circuit of the sub-fuel cell power supply device via the communication connection part, The power generation control circuit gives priority to the power generation command from the command circuit when performing the power generation control of the fuel cell, a fuel cell power supply system.

11. The command circuit divides the required power of the load by the rated power of each fuel cell constituting the fuel cell power supply system, and transmits the power generation command to the power generation control circuit so that the fuel cell generates power at the rated power by the number of integers of the divided value. The fuel cell power supply system according to claim 10.

12. A fuel cell, An output terminal part used to output the power of the fuel cell to a load, A power generation control circuit for performing power generation control of the fuel cell, A circuit connection part connected to the power generation control circuit and used to connect to a command circuit, The command circuit is configured to transmit a power generation command to the power generation control circuit when connected to the circuit connection part, The power generation control circuit performs the power generation control of the fuel cell based on the power generation command from the command circuit when the command circuit is connected to the circuit connection part, The command circuit monitors the power supply from the commercial power supply to the load when connected to the circuit connection part, and is configured to transmit a start command to the power generation control circuit based on the occurrence of a power failure in the commercial power supply, The power generation control circuit starts the fuel cell based on the input of the start command from the command circuit in a situation where the command circuit is connected to the circuit connection part, A power storage connection part that is connected to the output terminal part and used to connect a power storage device, And a connection switch capable of switching ON / OFF, The power storage connection part is connected to the fuel cell via the connection switch, A changeover switch provided between the fuel cell and the output terminal part and capable of switching between a first connection state and a second connection state is provided, In the first connection state, the power storage connection part is connected to the output terminal part via the connection switch and the changeover switch. In the second connection state, the power storage connection part is connected to the output terminal part via the changeover switch without passing through the connection switch, which is a fuel cell power supply device.

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