Work machine, fuel cell system, and method for controlling fuel cell system

Abstract

To reduce electric power which should be reserved for start in a work machine including a plurality of fuel cells.SOLUTION: Upon receiving a command signal for starting a work machine, a main control device outputs an activation command to a first fuel cell module among a plurality of fuel cell modules. Upon detecting the activation of the first fuel cell module, the main control device outputs an activation command to a second fuel cell module, which is different from the first fuel cell module, among the plurality of fuel cell modules.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a work machine, a fuel cell system, and a method for controlling the fuel cell system.

Background Art

[0002] In the technical field related to work machines, an extra-large truck equipped with a fuel cell system including a plurality of fuel cell modules as disclosed in Patent Document 1 is known. A fuel cell generates electrical energy by a chemical reaction between hydrogen and oxygen. Hydrogen as fuel is supplied from a tank filled with hydrogen gas. Also, oxygen is supplied from the atmosphere. Therefore, auxiliary devices such as a fuel pump and an air compressor are provided for the fuel cell to operate the fuel cell.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, auxiliary devices for operating a fuel cell are driven by electric power. Therefore, the fuel cell system needs to include a power storage device for storing power at startup. When the fuel cell system includes a plurality of fuel cells, the greater the number of fuel cells, the more power is required for startup, so a large-capacity power storage device is required. On the other hand, there is a desire to reduce the size of the power storage device provided in the fuel cell system.

[0005] An object of the present disclosure is to provide a work machine, a fuel cell system, and a method for controlling the fuel cell system that can reduce the power to be stored for startup in a work machine including a plurality of fuel cells.

Means for Solving the Problems

[0006] According to one aspect of the present invention, a working machine is a working machine including a working implement, and includes a fuel cell system supported by the vehicle body of the working machine and including a plurality of fuel cell modules connected to a bus bar, and a main control device. When receiving a command signal to start the working machine, the main control device outputs a start command to a first fuel cell module among the plurality of fuel cell modules. When detecting the start of the first fuel cell module, the main control device outputs a start command to a second fuel cell module different from the first fuel cell module among the plurality of fuel cell modules.

Effect of the Invention

[0007] According to the above aspect, the working machine can reduce the electric power to be stored for startup.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0009] 〈First Embodiment〉 《Configuration of Working Machine 1》 FIG. 1 is a schematic diagram showing the configuration of a working machine 1 according to the first embodiment. The working machine 1 according to the first embodiment is, for example, a hydraulic excavator. The working machine 1 includes a traveling body 110, a revolving body 120, a working device 130, a cab 140, and a main control device 145. The working machine 1, which is a hydraulic excavator, excavates and levels earth and sand at a work site or the like. The traveling body 110 and the revolving body 120 constitute the vehicle body.

[0010] The traveling body 110 supports the working machine 1 so as to be capable of traveling. The traveling body 110 has a pair of left and right crawlers. The working machine 1 moves forward, turns, or moves backward by the rotation of the pair of crawlers. The revolving body 120 is supported by the traveling body 110 so as to be rotatable about a turning center. The revolving body 120 supports the working device 130, the cab 140, the machine room 150, and the fuel cell system 20.

[0011] The cab 140 is a place where the operator of the working machine 1 boards and performs operations and controls. The cab 140 is disposed, for example, at the left front end portion of the revolving body 120. The main control device 145 is mounted in the cab 140 of the working machine 1.

[0012] The fuel cell system 20 described later is disposed in the machine room 150. The machine room 150 is disposed, for example, behind the cab 140. The machine room 150 forms a space for disposing the fuel cell system 20.

[0013] The working device 130 is movably supported by the vehicle body of the working machine 1. The working device 130 includes a boom 131, an arm 132, and an attachment 133 which is a working tool. The attachment 133 is an example of a working tool. The attachment 133 in the example shown in FIG. 1 is a bucket. The base end portion of the boom 131 is rotatably attached to the front end portion of the revolving body 120. The base end portion of the arm 132 is rotatably attached to the tip end portion of the boom 131. The attachment 133 is rotatably attached to the tip end portion of the arm 132.

[0014] The work machine 1 includes a plurality of actuators for driving the work implement 130. The plurality of actuators include, for example, a boom cylinder 131C, an arm cylinder 132C, and an attachment cylinder 133C.

[0015] The boom cylinder 131C is a hydraulic cylinder for driving the boom 131. The base end portion of the boom cylinder 131C is attached to the revolving body 120. The tip end portion of the boom cylinder 131C is attached to the boom 131. The arm cylinder 132C is a hydraulic cylinder for driving the arm 132. The base end portion of the arm cylinder 132C is attached to the boom 131. The tip end portion of the arm cylinder 132C is attached to the arm 132. The attachment cylinder 133C is a hydraulic cylinder for driving the attachment 133. The base end portion of the attachment cylinder 133C is attached to the arm 132. The tip end portion of the attachment cylinder 133C is attached to the attachment 133.

[0016] 《Configuration of the driver's cab》 FIG. 2 is a schematic diagram showing the configuration of the driver's cab 140 of the work machine 1 according to the first embodiment.

[0017] As shown in FIG. 2, the driver's cab 140 is provided with a driver's seat 141, a left operation lever 142LO, a right operation lever 142RO, a left foot pedal 142LF, a right foot pedal 142RF, a left travel lever 142LT, a right travel lever 142RT, and a start operation switch 143. The left operation lever 142LO and the right operation lever 142RO are arranged on the left and right sides of the driver's seat 141 in the driver's cab 140. Also, the left foot pedal 142LF and the right foot pedal 142RF are arranged on the floor surface in front of the driver's seat 141 in the driver's cab 140.

[0018] The left operation lever 142LO, which is arranged on the left side facing the front of the driver's cab, is an operating device for performing the turning operation of the revolving body 120 and the excavation / dumping operation of the arm 132. Also, the right operation lever 142RO, which is arranged on the right side facing the front of the driver's cab, is an operating device for performing the excavation / dumping operation of the attachment 133 and the raising / lowering operation of the boom 131.

[0019] In addition, the left travel lever 142LT and the right travel lever 142RT are operating devices for controlling the operation of the traveling body 110, that is, for controlling the travel of the work machine 1. The left travel lever 142LT, which is arranged on the left side facing the front of the driver's cab, corresponds to the rotational drive of the left crawler of the traveling body 110. The right travel lever 142RT, which is arranged on the right side facing the front of the driver's cab, corresponds to the rotational drive of the right crawler of the traveling body 110. Note that the left foot pedal 142LF and the right foot pedal 142RF are interlocked with the left travel lever 142LT and the right travel lever 142RT, respectively, and the travel can also be controlled by the left foot pedal 142LF and the right foot pedal 142RF.

[0020] FIG. 3 is a schematic block diagram showing the configuration of the fuel cell system 20 and the drive system 30 of the work machine 1 according to the first embodiment. The work machine 1 includes a fuel cell system 20 and a drive system 30. The fuel cell system 20 generates electric power for driving the work machine 1. The fuel cell system 20 generates electric power for driving the drive system 30. The electric power generated by the fuel cell system 20 is output to the drive system 30 via the bus bar B. The drive system 30 drives the work implement 130 and the traveling body 110 with the electric power generated by the fuel cell system 20.

[0021] The fuel cell system 20 includes a plurality of fuel cell modules 21 and a power storage device module 22 connected in parallel to the bus bar B.

[0022] Each fuel cell module 21 includes a fuel cell 211, a power converter 212, a compensator 213, and a fuel cell control device 214. The fuel cell 211 generates electric power through an electrochemical reaction between hydrogen and oxygen. The power converter 212 is, for example, a DC-DC converter and is configured to be able to control the generated electric power of the fuel cell 211. The power converter 212 converts the electric power generated by the fuel cell 211 and supplies it to the bus B. The auxiliary device 213 is a device for operating the fuel cell 211. The fuel cell module 21 includes, as the auxiliary device 213, a hydrogen pump for supplying hydrogen gas to the fuel cell 211, an air compressor for generating compressed air to be supplied to the fuel cell 211, a water pump for supplying cooling water for cooling the fuel cell 211, and the like. The fuel cell control device 214 controls the fuel cell module 21 according to a command from the main control device 145. The fuel cell control device 214 monitors the state of the fuel cell 211 and outputs data indicating the state of the fuel cell 211 to the main control device 145. The fuel cell control device 214 is an example of a monitoring device.

[0023] The energy storage device module 22 includes an energy storage device 221 and a power converter 222. The energy storage device 221 is configured to be able to store or discharge surplus electric power on the bus B. The power converter 222 is, for example, a DC-DC converter and controls the input and output of the electric power of the energy storage device 221. The power converter 222 outputs electric power from the energy storage device 221 according to a command from the main control device 145. The energy storage device 221 is, for example, a capacitor.

[0024] The drive system 30 includes a hydraulic drive module 31 and a slewing module 32.

[0025] The hydraulic drive module 31 includes an inverter 311, an electric motor 312, a hydraulic pump 313, and a hydraulic actuator 314. The inverter 311 converts the direct current from the bus B into a three-phase alternating current and supplies it to the electric motor 312. The electric motor 312 rotates by the supplied three-phase alternating current and drives the hydraulic pump 313. The hydraulic pump 313 discharges hydraulic oil for supplying the hydraulic actuator 314. The hydraulic oil discharged from the hydraulic pump 313 is supplied to the hydraulic actuator 314 via a control valve (not shown). The hydraulic actuator 314 is driven by the supplied hydraulic oil. The hydraulic actuator 314 includes a boom cylinder 131C, an arm cylinder 132C, an attachment cylinder 133C, and a travel motor 134. The rotational force generated by the travel motor 134 is transmitted to the traveling body 110.

[0026] The slewing module 32 includes an inverter 321 and an electric slewing motor 322. The inverter 321 converts the direct current from the bus B into a three-phase alternating current and supplies it to the electric slewing motor 322. The electric slewing motor 322 rotates by the supplied three-phase alternating current and rotates the slewing body 120 with respect to the traveling body 110.

[0027] 《Control at Startup of the Working Machine 1》 FIG. 4 is a flowchart showing the control at startup of the working machine 1 according to the first embodiment. When the operator operates the start operation switch 143, the start operation switch 143 outputs a command signal for starting the work machine 1 to the main control device 145. The start operation switch 143 is, for example, a switch that outputs a command signal for starting the work machine 1 when pressed by the operator. When a command signal for starting the work machine 1 is input from the start operation switch 143 to the main control device 145 by the operation of the operator, the main control device 145 starts the fuel cell system 20 in the following procedure. First, the main control device 145 outputs a command signal to the power converter 222 of the power storage device module 22 so as to supply predetermined power to the bus B (step S1). The predetermined power may be power that can drive the auxiliary device 213 of at least one fuel cell module 21 among the plurality of fuel cell modules 21.

[0028] Next, the main control device 145 selects at least one fuel cell module 21 to be started first from among the plurality of fuel cell modules 21 (step S2). Hereinafter, the selected fuel cell module 21 will be referred to as the first fuel cell module. The first fuel cell module may be predetermined, may be randomly selected by the main control device 145, or may be selected in a scheduled order so that the total operating time is the same. When the power converter 222 of the power storage device module 22 supplies power to the bus B that is sufficient to drive the auxiliary devices 213 of the plurality of fuel cell modules 21, the plurality of fuel cell modules 21 may be selected as the first fuel cell module.

[0029] The main control device 145 outputs a start command to the fuel cell control device 214 of the first fuel cell module selected in step S2 (step S3). When the fuel cell control device 214 of the first fuel cell module receives the start command, it drives the auxiliary device 213 with the power of the bus B. That is, at this time, the auxiliary device 213 of the first fuel cell module is driven by the power supplied from the power storage device 221. When hydrogen and oxygen are supplied to the fuel cell 211 of the first fuel cell module by driving the auxiliary device 213, the fuel cell 211 reacts hydrogen and oxygen to generate power.

[0030] The main control device 145 detects the startup of the fuel cell 211 of the first fuel cell module (step S4). Specifically, the fuel cell control device 214 of the first fuel cell module monitors the state of the fuel cell 211 and outputs data indicating the state of the fuel cell 211. The state of the fuel cell 211 includes states such as stopped and startup completed. The data indicating the startup completed state is an example of a notification indicating that the fuel cell 211 is operating. The main control device 145 receives the data output from the fuel cell control device 214 of the first fuel cell module and detects the state of the fuel cell 211. The main control device 145 detects the startup of the fuel cell 211 of the first fuel cell module based on the data from the fuel cell control device 214 of the first fuel cell module.

[0031] When the main control device 145 detects the startup of the fuel cell 211 of the first fuel cell module, it outputs a command signal to the fuel cell control device 214 of the first fuel cell module so as to supply a predetermined power to the bus B (step S5). The predetermined power may be any power that can drive the auxiliary device 213 of at least one fuel cell module 21 among the plurality of fuel cell modules 21. The fuel cell control device 214 of the first fuel cell module causes the power converter 212 to supply the power generated by the fuel cell 211 to the bus B based on the command signal from the main control device 145.

[0032] Next, the main control device 145 selects at least one fuel cell module 21 to be started next from among the plurality of fuel cell modules 21 that are not operating (step S6). Hereinafter, the next selected fuel cell module 21 of the first fuel cell module is referred to as the second fuel cell module. The second fuel cell module is a fuel cell module 21 different from the first fuel cell module. The second fuel cell module may be predetermined, may be randomly selected by the main control device 145, or may be selected in the order scheduled so that the total operating time is the same. Note that the main control device 145 selects a second fuel cell module that can drive the auxiliary device 213 with the power output by the first fuel module that is already operating. Note that when the fuel cell 211 of the first fuel cell module supplies the bus B with enough power to drive the auxiliary devices 213 of the plurality of fuel cell modules 21, the plurality of fuel cell modules 21 may be selected as the second fuel cell module.

[0033] The main control device 145 outputs a start command to the fuel cell control device 214 of the second fuel cell module selected in step S6 (step S7). When the fuel cell control device 214 of the second fuel cell module receives the start command, it drives the auxiliary device 213 with the power of the bus B. Although there is a possibility that the remaining amount of the power stored in the power storage device 221 has run out, the auxiliary device 213 of the second fuel cell module can be driven by the power supplied from the first fuel cell module. When hydrogen and oxygen are supplied to the fuel cell 211 of the second fuel cell module by driving the auxiliary device 213, the fuel cell 211 reacts hydrogen and oxygen to generate power.

[0034] The main control device 145 detects the startup of the fuel cell 211 of the second fuel cell module (step S8). Specifically, the fuel cell control device 214 of the second fuel cell module monitors the state of the fuel cell 211 and outputs data indicating the state of the fuel cell 211. The state of the fuel cell 211 includes states such as stopped and startup completed. The data indicating the startup completed state is an example of a notification indicating that the fuel cell 211 is operating. The main control device 145 receives the data output from the fuel cell control device 214 of the second fuel cell module and determines the state of the fuel cell 211. The main control device 145 detects the startup of the fuel cell 211 of the second fuel cell module based on the data from the fuel cell control device 214 of the second fuel cell module.

[0035] When the main control device 145 detects the startup of the fuel cell 211 of the second fuel cell module, it outputs a command signal to the fuel cell control device 214 of the second fuel cell module so as to supply predetermined power to the bus B (step S9). The fuel cell control device 214 of the second fuel cell module causes the power converter 212 to supply the power generated by the fuel cell 211 to the bus B based on the command signal from the main control device 145.

[0036] Thereafter, while there is a fuel cell module 21 that has not been started, the main control device 145 drives the auxiliary device 213 of the fuel cell module 21 that has not been started with the power output by the fuel module that is already operating.

[0037] When the startup of all the fuel cell modules 21 is completed, the main control device 145 permits the operation of the working machine 1 according to the operation of the operating device by the operator. The main control device 145 receives the operation of the operating device by the operator and outputs control commands to the inverter 311 of the hydraulic drive module 31 and the inverter 321 of the swing module 32 according to the operation amount.

[0038] 《Function and Effect》 As described above, the main control device 145 according to the first embodiment functions as follows. When the work machine 1 is started, if the main control device 145 receives a command signal to start the fuel cell system 20 when all of the plurality of fuel cells 211 are stopped, it outputs a command signal to drive the auxiliary device 213 of the first fuel cell module among the plurality of fuel cell modules 21. When the first fuel cell module is operating, the main control device 145 outputs a command signal to drive the auxiliary device 213 of the second fuel cell module among the plurality of fuel cell modules 21. Therefore, the power storage device 221 only needs to store the power to be supplied to the auxiliary device 213 until at least the start-up of the first fuel cell module among the plurality of fuel cell modules 21 is completed. Therefore, the power storage device 221 does not need to have a capacity to drive the auxiliary devices 213 of all the fuel cell modules 21 at startup. That is, the fuel cell system 20 according to the first embodiment can reduce the size of the power storage device 221. Further, when the power storage device 221 is a capacitor, since the capacity with respect to the size is smaller than that of a battery, the power storage device 221 provided in the work machine 1 can be reduced in size by performing the control according to the first embodiment. Therefore, the fuel cell system 20 according to the first embodiment can reduce the power to be stored before startup.

[0039] FIG. 5 is a schematic block diagram showing the configuration of a computer according to the first embodiment. The computer 90 includes a processor 91, a main memory 92, a storage 93, and an interface 94. The above-described main control device 145 and the fuel cell control device 214 are implemented in the computer 90. The operations of the above-described respective processing units are stored in the storage 93 in the form of a program. The processor 91 reads the program from the storage 93, expands it in the main memory 92, and executes the above processing according to the program. Further, the processor 91 secures a storage area corresponding to each of the above-described storage units in the main memory 92 according to the program. Examples of the processor 91 include a CPU (Central Processing Unit), a GPU (Graphic Processing Unit), and a microprocessor.

[0040] The program may be for realizing a part of the functions to be exhibited by the computer 90. For example, the program may exhibit functions by combination with other programs already stored in the storage or by combination with other programs implemented in other devices. In other embodiments, the computer 90 may include, in addition to or instead of the above configuration, a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device). Examples of the PLD include a PAL (Programmable Array Logic), a GAL (Generic Array Logic), a CPLD (Complex Programmable Logic Device), and an FPGA (Field Programmable Gate Array). In this case, some or all of the functions realized by the processor 91 may be realized by the integrated circuit. Such an integrated circuit is also included as an example of the processor. In other embodiments, the computer 90 may be virtualized on one or more computers.

[0041] Examples of the storage 93 include a magnetic disk, a magneto-optical disk, an optical disk, a semiconductor memory, and the like. The storage 93 may be an internal medium directly connected to the bus of the computer 90, or may be an external medium connected to the computer 90 via the interface 94 or a communication line. Further, when this program is distributed to the computer 90 via a communication line, the computer 90 that has received the distribution may expand the program in the main memory 92 and execute the above processing. In at least one embodiment, the storage 93 is a non-transitory tangible storage medium.

[0042] Also, the program may be for realizing a part of the functions described above. Further, the program may be a so-called difference file (difference program) that realizes the functions described above in combination with other programs already stored in the storage 93.

[0043] 〈Other Embodiments〉 As described above, one embodiment has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like are possible. For example, the main control device 145 according to the above-described embodiment may be configured by a single computer, or the configuration of the main control device 145 may be divided and arranged among a plurality of computers, and the plurality of computers may function as the main control device 145 by cooperating with each other. At this time, some of the computers constituting the main control device 145 may be mounted inside the working machine 1, and other computers may be provided outside the working machine 1. Also, the main control device 145 according to the above-described embodiment may have the function of the fuel cell control device 214. In this case, each fuel cell module 21 does not necessarily have to include the fuel cell control device 214, and the power converter 212 and the compensator 213 of each fuel cell module 21 may operate based on a command signal from the main control device 145. Further, the main control device 145 may have a function of monitoring the state of the fuel cell 211 as a monitoring device.

[0044] Also, although the working machine 1 according to the above-described embodiment is a hydraulic excavator, it is not limited thereto. For example, the working machine 1 according to other embodiments may be other working machines such as a wheel loader or a dump truck.

[0045] Also, in the above-described embodiment, a capacitor is given as an example of the power storage device 221, but it is not limited thereto. For example, the power storage device 221 of the working machine 1 according to other embodiments may be a battery.

[0046] In addition, in the above-described embodiment, the working machine 1 has been described with respect to two fuel cell modules as shown in FIG. 3, but it is not limited thereto. The working machine 1 according to other embodiments may include three or more fuel cell modules.

[0047] Also, in the above-described embodiment, the start operation switch 143 for starting the working machine 1 is a switch that outputs a start signal when pressed by the operator, but it is not limited thereto. The start operation switch 143 may be, for example, a key cylinder into which a key is inserted, and a key switch that operates by inserting a key into the key cylinder and rotating the key from the off position through the key-on position to the start position. Further, the start operation switch 143 may be, for example, a portable operation device possessed by the operator. When the operator operates the portable operation device, wireless communication is performed between the portable operation device and the main control device 145, and the working machine 1 may be started on the condition that the communication is established. The portable operation device may be, for example, a remote control key with a built-in electronic chip, or a portable computer device such as a smartphone or a personal digital assistant. Also, the start operation switch 143 may be arranged, for example, at a remote location and configured to be able to start the working machine 1 by remote operation.

Explanation of Reference Numerals

[0048] 1…Work machine 110…Traveling body 120…Slewing body 130…Work implement 131…Boom 131C…Boom cylinder 132…Arm 132C…Arm cylinder 133…Attachment 133C…Attachment cylinder 134…Traveling motor 140…Operator's cab 141…Operator's seat 142LF…Left foot pedal 142LO…Left operation lever 142LT…Left traveling lever 142RF…Right foot pedal 142RO…Right operation lever 142RT…Right traveling lever 145…Main control device 20…Fuel cell system 21…Fuel cell module 211…Fuel cell 212…Power converter 213…Compensator 214…Fuel cell control device 22…Energy storage device module 221…Energy storage device 222…Power converter 30…Drive system 31…Hydraulic drive module 311…Inverter 312…Electric motor 313…Hydraulic pump 314…Hydraulic actuator 32…Slewing module 321…Inverter 322…Electric slewing motor B…Bus bar

Claims

1. A working machine equipped with a working implement, comprising a fuel cell system supported by the vehicle body of the working machine and including a plurality of fuel cell modules connected to a bus bar, and a main control device . When the main control device receives a command signal to start the working machine, it outputs a start command to a first fuel cell module among the plurality of fuel cell modules, and when detecting the start of the first fuel cell module, outputs a start command to a second fuel cell module different from the first fuel cell module among the plurality of fuel cell modules Working machine.

2. Auxiliary devices for operating the corresponding fuel cells are provided corresponding to each of the plurality of fuel cell modules, and the main control device when receiving a command signal to start the working machine, outputs a command signal to drive the auxiliary device corresponding to the first fuel cell module, and when detecting the start of the first fuel cell module, outputs a command signal to drive the auxiliary device corresponding to the second fuel cell module The working machine according to claim 1.

3. A power storage device connected to the bus bar and a power converter provided between the power storage device and the bus bar, and when the main control device receives a command signal to start the working machine, it outputs a command signal to supply the power of the power storage device to the bus bar to the power converter The working machine according to claim 1.

4. Comprising a monitoring device that outputs data indicating the state of the first fuel cell module, and the main control device detects the start of the first fuel cell module based on the data output from the monitoring device, and when detecting the start of the first fuel cell module, outputs a start command to the second fuel cell module The working machine according to claim 1.

5. The power storage device is a capacitor The working machine according to claim 3.

6. The power storage device is a battery The working machine according to claim 3.

7. When all the startups of the plurality of fuel cell modules are completed, the main control device permits the operation of the working machine The working machine according to claim 1.

8. A fuel cell system that generates electric power for driving a working machine equipped with a working implement, comprising a plurality of fuel cell modules supported by the vehicle body of the working machine and connected to a bus bar, and a main control device . The main control device When receiving a command signal to start the work machine, an activation command is output to a first fuel cell module among the plurality of fuel cell modules, when detecting activation of the first fuel cell module, an activation command is output to a second fuel cell module different from the first fuel cell module among the plurality of fuel cell modules Fuel cell system.

9. A method for controlling a fuel cell system that includes a plurality of fuel cell modules supported by a vehicle body and connected to a bus bar and generates electric power for driving a work machine equipped with a working device, comprising: when receiving a command signal to start the work machine, causing an activation command to be output to a first fuel cell module among the plurality of fuel cell modules; when detecting activation of the first fuel cell module, causing an activation command to be output to a second fuel cell module different from the first fuel cell module among the plurality of fuel cell modules and comprising a method.

Images