Work vehicle

Abstract

To provide a technique that enables the amount of hydrogen remaining in a hydrogen tank to be accurately grasped.SOLUTION: A work vehicle 1 includes an FC module 24, a motor 31 driven by power output from the FC module 24, a hydrogen tank 13 for storing hydrogen as fuel for the FC module 24, and an FC system ECU 71 for calculating the amount of power that can be generated by the FC module 24 when hydrogen is used until the amount of hydrogen in the hydrogen tank 13 decreases from a current amount to a predetermined amount.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a work vehicle.

Background Art

[0002] Patent Document 1 discloses a vehicle including a motor, a fuel cell system using hydrogen as fuel, and a hydrogen tank. The fuel cell system generates electricity by hydrogen supplied from the hydrogen tank, and drives the motor with the generated electricity to run the vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The above fuel cell system may be applied to a work vehicle used for agricultural work. The work vehicle is frequently used during the work period, but is hardly used and may be maintained in a stopped state for a long time outside the work period. Here, when the work period ends and the work vehicle is stopped for a long time, hydrogen may remain in the hydrogen tank mounted on the work vehicle. Thus, when hydrogen remains in the hydrogen tank of the work vehicle stopped for a long time, the handling of the remaining hydrogen may become a problem. Therefore, a technique that enables appropriate grasping of the amount of hydrogen remaining in the hydrogen tank is desired.

Means for Solving the Problems

[0005] The work vehicle according to the present disclosure includes a fuel cell, a motor driven by electric power output from the fuel cell, a hydrogen tank that stores hydrogen which is fuel for the fuel cell, and a control device that calculates the power that can be generated by the fuel cell when hydrogen is used until the amount of hydrogen in the hydrogen tank reaches a predetermined amount from the current amount.

Advantages of the Invention

[0006] According to the present disclosure, it becomes possible to appropriately grasp the amount of hydrogen remaining in the hydrogen tank.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0008] First, the contents of the embodiment will be listed and described. [Overview of the Embodiment]

[0009] (1) The work vehicle according to the present disclosure includes a fuel cell, a motor driven by electric power output from the fuel cell, a hydrogen tank that stores hydrogen which is fuel for the fuel cell, and a control device that calculates the power that can be generated by the fuel cell when hydrogen is used until the amount of hydrogen in the hydrogen tank reaches a predetermined amount from the current amount.

[0010] According to the above configuration, since the control device calculates the power that can be generated by the fuel cell when hydrogen is used until the hydrogen amount in the hydrogen tank reaches a predetermined amount from the current amount, if necessary, the hydrogen amount in the hydrogen tank can be output to the outside as power. As a result, it becomes possible to appropriately grasp the remaining hydrogen amount in the hydrogen tank.

[0011] (2) In the work vehicle of (1) above, the work vehicle may further include an output device that outputs the power that can be generated calculated by the control device. In this case, the power that can be generated can be output via the output device.

[0012] (3) In the work vehicle of (2) above, the work vehicle may further include an operation unit that causes the output device to output the power that can be generated when an operation input is received via a first operation member. In this case, the power that can be generated can be output in response to a request from the outside such as an occupant.

[0013] (4) In the work vehicle of (2) or (3) above, the control device can acquire a consumption command, and when the control device acquires the consumption command, the fuel cell generates power until the hydrogen amount in the hydrogen tank becomes equal to or less than the predetermined amount. In this case, it is preferable that after the operation unit causes the output device to output the power that can be generated, when an operation input is received via a second operation member, the consumption command is output to the control device. In this case, when the control device acquires a consumption command, the fuel cell starts generating power and stops generating power when the hydrogen amount in the hydrogen tank becomes equal to or less than a predetermined amount. Therefore, for example, when the work vehicle is stopped for a long time, if the control device is made to acquire a consumption command, the hydrogen remaining in the hydrogen tank can be consumed until it becomes equal to or less than a predetermined amount, and the hydrogen amount in the hydrogen tank of the work vehicle stopped for a long time can be reduced. Also, since the operation unit outputs a consumption command to the control device when an operation input is received via a second operation member after causing the output device to output the power that can be generated, it is possible to make a judgment as to whether or not to operate the second operation member after allowing the outside to grasp the hydrogen amount in the hydrogen tank. As a result, the hydrogen remaining in the hydrogen tank can be appropriately processed.

[0014] (5) In the work vehicle of (4) above, when further including a power storage device that stores the power generated by the fuel cell, when the consumption command is acquired, the power generated by the fuel cell may be stored in the power storage device. In this case, the power obtained from the hydrogen remaining in the hydrogen tank can be stored in the power storage device.

[0015] (6) In the work vehicle of (5) above, when further including an auxiliary power storage device, when the power storage device is fully charged, the power generated by the fuel cell may be stored in the auxiliary power storage device. In this case, even when the power storage device is fully charged, the power obtained from the hydrogen remaining in the hydrogen tank can be stored by the auxiliary power storage device.

[0016] (7) Also, in the work vehicle of (5) above, when further including an external output unit that outputs the power generated by the fuel cell to the outside, when the power storage device is fully charged, the power generated by the fuel cell may be output to an external device connected to the external output unit. In this case, even when the power storage device is fully charged, the power obtained from the hydrogen remaining in the hydrogen tank can be consumed by the external device.

[0017] Also, from another perspective, the present disclosure is a control device. This control device is used in a work vehicle including a fuel cell, a motor driven by the power output from the fuel cell, and a fuel tank that stores the fuel of the fuel cell. The control device includes a processing unit that executes a process of calculating the power that can be generated by the fuel cell when hydrogen is used until the hydrogen amount in the hydrogen tank reaches a predetermined amount from the current amount.

[0018] [Details of the Embodiment] Hereinafter, preferred embodiments will be described with reference to the drawings. Note that at least a part of each of the embodiments described below may be arbitrarily combined.

[0019] 〔Overall Structure of Work Vehicle〕 FIG. 1 is a perspective view showing an example of the overall structure of a work vehicle 1. FIG. 2 is a right side view of the work vehicle 1 with some exterior parts (such as the bonnet 34 and the cover 111) removed. As shown in FIGS. 1 and 2, the work vehicle 1 is a vehicle used for agricultural work, specifically a tractor. However, the work vehicle 1 is not limited to a tractor and may be a moving body such as an agricultural machine, a construction machine, and a utility vehicle.

[0020] The work vehicle 1 includes a vehicle body 11, a traveling device 12 that supports the vehicle body 11, a driver's seat 15, and a cabin 16. The vehicle body 11 includes a chassis 41, a bonnet 34, a cover 111, a cabin 16, and a fender for the rear wheel 12B. More specifically, on the chassis 41 of the vehicle body 11, a bonnet 34, a cover 111, and a cabin 16 are arranged in order from the front to the rear.

[0021] The work vehicle 1 further has a tank unit 21 and a drive device 14. The tank unit 21 has a plurality of hydrogen tanks 13 (see FIG. 2) that store fuel inside. The drive device 14 outputs a driving force using the fuel stored in the tank unit 21. The fuel is a liquid or a gas, such as hydrogen, methane, carbon monoxide (CO), etc. The fuel in this embodiment is hydrogen. Each of the plurality of tanks 13 stores hydrogen gas. The work vehicle 1 is a fuel cell vehicle (FCV: Fuel Cell Vehicle). The work vehicle 1 has a power generation system (FC power generation system) using a fuel cell. The work vehicle 1 travels using the power from the FC power generation system as an energy source. Note that the FC power generation system in this embodiment generates power using hydrogen. The FC power generation system may generate power using methane or carbon monoxide (CO).

[0022] The drive device 14 includes a fuel cell module (FC module) 24, a battery unit 30, and an electric motor 31 (see FIG. 3; hereinafter also referred to as "motor 31"). The battery unit 30 houses a battery pack 30A (see FIG. 4). The battery unit 30 stores the power output by the FC module 24. The work vehicle 1 has a hydrogen gas pipe 22. Hydrogen gas is filled into each hydrogen tank 13 from a filling port 52 (see FIG. 4) provided at the end of the pipe 22. The hydrogen in the hydrogen tank 13 is supplied to the FC module 24 through the pipe 22.

[0023] The cabin 16 is a compartmentalized driver's cab. The cabin 16 has front pillars, rear pillars, and a roof. The front pillars are arranged on the left and right sides in front of the driver's seat 15, and the rear pillars are arranged on the left and right sides behind the driver's seat 15. Instead of the cabin 16, the work vehicle 1 may have a canopy or a rollover protective structure (ROPS). When the work vehicle 1 does not have the cabin 16, the tank unit 21 is arranged above the driver's seat 15 by a mounting frame 17 described later.

[0024] The traveling device 12 is composed of front wheels 12A and rear wheels 12B. Both of these are arranged symmetrically with respect to the vehicle body 11. One or both of the front wheels 12A and the rear wheels 12B rotate by the power of the motor 31. One or both of the wheels 12A, 12B (drive wheels) that rotate by the power of the motor 31 may be crawlers (endless tracks).

[0025] As shown in FIG. 2, on the front wheel 12A corresponding portion of the chassis 41, in order from the front side to the rear side, a first radiator 48, an FC module 24, and a second radiator 49 are mounted. The first radiator 48 and the FC module 24 are covered by a bonnet 34. The second radiator 49 is covered by a cover 111.

[0026] As shown in FIG. 1, the upper surface of the cover 111 is higher than the uppermost end of the bonnet 34 but lower than the uppermost end of the steering wheel in the driver's seat 15. Also, the rear end portion of the bonnet 34 is located at a position lower than the cover 111, and the upper surface of the bonnet 34 is formed in a tapered shape that gradually becomes lower from the rear end portion toward the front end portion. For this reason, the structure is such that it is difficult to obstruct the forward view from the operator sitting in the driver's seat 15.

[0027] 〔Internal Structure of the Work Vehicle〕 FIG. 3 is a perspective view showing an example of the internal structure of the work vehicle 1. As shown in FIG. 3, the chassis 41 constituting the vehicle body 11 has a front frame 32 and a transmission case 33. The front frame 32 is made of a steel frame having a long shape in the front-rear direction. The transmission case 33 is connected to the rear portion of the front frame 32. The framework of the vehicle body 11 is formed by the transmission case 33 and the front frame 32.

[0028] A mounting frame 17 is connected to the chassis 41. The mounting frame 17 is a frame for arranging the tank unit 21 above the cabin 16. The mounting frame 17 includes a ceiling frame 17A, a plurality of pillars 17B, and a pair of left and right reinforcing frames 17C. The ceiling frame 17A has a substantially rectangular shape with a longer front-rear direction than the left-right direction. The plurality of pillars 17B support the ceiling frame 17A from below. The pair of reinforcing frames 17C are provided on the left and right of the front end portion of the ceiling frame 17A.

[0029] The tank unit 21 is connected to the ceiling frame 17A in a horizontally placed state. As shown in FIG. 2, the ceiling frame 17A is located at a position higher than the roof of the cabin 16. Therefore, the tank unit 21 is arranged above the roof of the cabin 16. The reinforcing frame 17C is a reinforcing diagonal member that slopes downward from the front end of the ceiling frame 17A to the front frame 32. Therefore, the rigidity of the mounting frame 17 in the front-rear direction is enhanced as compared with the case where the ceiling frame 17A and the tank unit 21 are supported only by the pillar 17B.

[0030] A support frame 37 for supporting the battery unit 30 on the vehicle body 11 is connected to the chassis 41 of the work vehicle 1. Specifically, a motor 31 is mounted on the front frame 32 of the chassis 41, and the support frame 37 is attached to a portion of the front frame 32 corresponding to the motor 31. The support frame 37 is composed of, for example, a metal frame member and is attached in a cantilever state so as to protrude to the right from the front frame 32.

[0031] The transmission case 33 located behind the motor 31 has a power transmission mechanism inside. The power transmission mechanism includes a transmission, a clutch, and a differential gear, and decelerates or accelerates the rotation of the output shaft of the motor 31 and transmits it to the traveling device 12. In addition, the power transmission mechanism includes a branch mechanism that outputs a part of the power of the motor 31 to the PTO shaft 334 (see FIG. 4). The PTO shaft 334 is an output shaft that protrudes rearward from the transmission case 33.

[0032] A connecting device 44 (see FIG. 2), which is constituted by, for example, a three-point link mechanism, for connecting a working device 335 (see FIG. 4) for performing a desired agricultural work to the rear of the vehicle body 11 is attached to the transmission case 33. The three-point link mechanism can be constituted by, for example, an upper arm 44A protruding rearward from the transmission case 33 and a pair of left and right lower arms 44B. The working device 335 is, for example, a tiller and a baler.

[0033] The rotational motion of the PTO shaft 334 is transmitted to the input shaft of the working device 335 connected to the connecting device 44, for example, while the traveling device 12 is being driven. Therefore, the work vehicle 1 can drive the working device 335 by the power of the motor 31 while traveling on a farm field or the like.

[0034] [Regarding the power generation system of the work vehicle] FIG. 4 is a block diagram showing an example of the FC power generation system of the work vehicle 1. In FIG. 4, in addition to the FC power generation system, a motor 31 driven by the power generated by the FC power generation system, a traveling device 12, and a working device 335 are also shown. The FC power generation system includes, in addition to the FC module 24 and the battery unit 30 included in the drive device 14, a tank unit 21, a first DC / DC converter 64, a second DC / DC converter 65, and the like.

[0035] As shown in FIG. 4, the FC module 24 includes a fuel cell stack 24a, a boost circuit 24b, and an ECU 24c. The fuel cell stack (FC stack) 24a has a stacked structure in which a plurality of fuel cells (single cells) are stacked. The plurality of single cells are connected in series so as to obtain a desired voltage. Hydrogen as fuel and air (oxygen) are supplied to the FC stack 24a. The FC module 24 includes a compressor and a pump (not shown) for supplying hydrogen and air to the FC stack 24a. The FC stack 24a outputs (generates) power by an electrochemical reaction caused by hydrogen and air.

[0036] The hydrogen supplied to the FC stack 24a is supplied through the pipe 22 as described above. As shown in FIG. 4, the pipe 22 connects the FC stack 24a and the tank unit 21. The pipe 22 has a pipe portion 22A and a pipe portion 22B. The pipe portion 22A is a gas pipe connecting the filling port 52 and the tank unit 21. The pipe portion 22A guides the hydrogen introduced into the filling port 52 to the tank unit 21. The pipe portion 22B is a gas pipe connecting the FC stack 24a and the tank unit 21. The pipe portion 22B guides the hydrogen stored in the tank unit 21 to the FC stack 24a. A pressure sensor 53 for obtaining the amount of hydrogen in the tank unit 21 is provided in the pipe portion 22B. In addition, an on-off valve 50 is provided in the pipe portion 22B. The on-off valve 50 is provided between the pressure sensor 53 and the FC stack 24a. When the on-off valve 50 is opened, hydrogen is supplied to the FC module 24. When the on-off valve 50 is closed, the supply of hydrogen to the FC module 24 is stopped.

[0037] The tank unit 21 has a valve unit 51 in addition to the plurality of hydrogen tanks 13. A plurality of hydrogen tanks 13 are connected to the valve unit 51. The valve unit 51 has a function of distributing the hydrogen introduced from the filling port 52 to the plurality of hydrogen tanks 13, aggregating the hydrogen from the plurality of hydrogen tanks 13, adjusting it to a predetermined flow rate, and supplying it to the FC stack 24a. The tank unit 21 has a temperature sensor 54. The temperature sensor 54 measures the temperature inside the tank unit 21 as the temperature of hydrogen.

[0038] The electric power generated by the FC stack 24a is supplied to the boost circuit 24b. The boost circuit 24b boosts the supplied electric power to a predetermined voltage. The FC module 24 outputs the electric power boosted by the boost circuit 24b to the subsequent stage. The ECU 24c has a function of controlling each part of the FC module 24.

[0039] An electric circuit 25 is connected to the output end of the boost circuit 24b. The battery unit 30, the first DC / DC converter 64, and the second DC / DC converter 65 are connected to the boost circuit 24b via the electric circuit 25. The electric power output from the boost circuit 24b is supplied to each part via the electric circuit 25.

[0040] The battery unit 30 includes the battery pack 30A as described above. The battery pack 30A is a power storage device that stores the power generated by the FC module 24. The battery pack 30A discharges the stored power. The power discharged from the battery pack 30A is supplied to the inverter 62, the first DC / DC converter 64, and the second DC / DC converter 65 via the circuit 25.

[0041] The battery pack 30A includes a battery management unit (BMU) 30A1 in addition to a battery body that includes a plurality of secondary battery cells. The battery body included in the battery pack 30A is, for example, a lithium-ion battery. The rated voltage of the battery body (battery pack 30A) is several hundred volts. The BMU 30A1 has a function of monitoring and protecting the battery body. Further, the BMU 30A1 has a function of controlling the charge and discharge of the battery body and measuring the charge amount (e.g., SOC).

[0042] Also, the inverter 62 is connected to the circuit 25. The inverter 62 has a function of supplying the power generated by the FC power generation system to the motor 31 and controlling the rotational output of the motor 31. The inverter 62 has a function of converting the DC power supplied from the FC module 24 or the battery unit 30 into three-phase AC power. The AC power output by the inverter 62 is supplied to the motor 31. The inverter 62 controls the rotational output of the motor according to control commands and the like supplied from the control unit 70 described later. The inverter 62 has an ECU 62a. The ECU 62a has a function of controlling the circuits included in the inverter 62 based on the control commands and the like.

[0043] The motor 31 outputs a rotational force by the AC power supplied from the inverter 62. The rotational force output by the motor 31 is applied to the power transmission mechanism 33a in the transmission case 33. The power transmission mechanism 33a outputs all or part of the rotational force of the motor 31 to the traveling device 12. Also, when operating the work device 335, the power transmission mechanism 33a outputs part of the rotational force of the motor 31 to the work device 335.

[0044] The first DC / DC converter 64 steps down the voltage of the DC power output from the FC module 24 or the battery unit 30 to a first voltage (e.g., 12 volts). Connected to the output terminal of the first DC / DC converter 64 are a lead-acid battery 63, an auxiliary battery 67, an external output section 66, as well as electrical components and accessories such as lamps that the work vehicle 1 has. The power output by the first DC / DC converter 64 is supplied to these devices. The first DC / DC converter 64 has an ECU 64a. The ECU 64a has a function of controlling the circuits that the first DC / DC converter 64 has based on commands from a control unit or the like.

[0045] The lead-acid battery 63 stores the power output by the first DC / DC converter 64. The power stored in the lead-acid battery 63 is supplied to electrical components and accessories. An on-off switch 63a is provided between the lead-acid battery 63 and the first DC / DC converter 64. The on-off switch 63a has a function of opening and closing the connection between the lead-acid battery 63 and the first DC / DC converter 64. The external output section 66 is an interface for outputting the power from the first DC / DC converter 64 to devices outside the work vehicle 1. When an external device is connected to the external output section 66, the connected external device is supplied with the power from the first DC / DC converter 64. The auxiliary battery 67 includes a secondary battery such as a lead-acid battery or a lithium-ion battery. Similar to the lead-acid battery 63, the auxiliary battery 67 stores the power output by the first DC / DC converter 64. The auxiliary battery 67 is an auxiliary power storage device that subsidiarily stores the power generated by the FC module 24.

[0046] The second DC / DC converter 65 steps down the voltage of the DC power output from the FC module 24 or the battery unit 30 to a second voltage (e.g., 24 volts). Electrical components and accessories of the work vehicle 1 are connected to the output terminal of the second DC / DC converter 65, similar to the first DC / DC converter 64. The power output by the second DC / DC converter 65 is supplied to these devices. The second DC / DC converter 65 has an ECU 65a. The ECU 65a has a function of controlling the circuits of the second DC / DC converter 65 based on commands from a control unit and the like.

[0047] As shown in FIG. 4, the work vehicle 1 further has a control unit 70. The control unit 70 has functions of controlling the FC power generation system including the FC module 24, receiving operation inputs from passengers, and controlling the entire work vehicle 1 based on the received operation inputs.

[0048] In FIG. 4, electronic control units such as ECU 24c, ECU 62a, ECU 64a, ECU 65a, and BMU 30A1 are equipped with, for example, a processor, a storage device, and an input / output interface. Also, these electronic control units are connected to each other by, for example, CAN (Controller Area Network) and can communicate with each other. The control unit 70 is also connected to the CAN.

[0049] Devices such as the on-off valve 50, the pressure sensor 53, the temperature sensor 54, and the switch 63a are also connected to the CAN. Therefore, the control unit 70 can transmit control commands to these devices through the CAN and receive outputs provided by these devices.

[0050] The control unit 70 has a function of executing a consumption process that forcibly consumes the hydrogen remaining in the tank unit 21.

[0051] [Regarding the control unit 70 according to the embodiment] FIG. 5 is a block diagram showing a configuration example of the control unit 70 according to the embodiment. The control unit 70 includes an FC system ECU 71, an FC display panel 72, a main ECU 73, a main display panel 74, an operating device 75, a display switch 76, and an exhaustion switch 77. The FC system ECU 71 and the main ECU 73 are connected to the CAN. Therefore, the FC system ECU 71 and the main ECU 73 can communicate with the electronic control units and various devices shown in FIG. 4.

[0052] The FC system ECU 71 and the main ECU 73 include, for example, a processor (processing unit), a storage device, and an input / output interface. The processor includes a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), etc. The storage device includes, for example, a flash memory, a hard disk, a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The storage device stores a computer program for causing the processor to execute and necessary information. The processor realizes various processing functions of the processor by executing a computer program stored in a computer-readable non-transitory recording medium such as the storage device.

[0053] The FC system ECU 71 has a function of controlling an FC power generation system including the FC module 24. In addition, when the FC system ECU 71 acquires a consumption command, it has a function as a control device that causes the FC module 24 to generate power until the hydrogen amount in the tank unit 21 becomes equal to or less than the lower limit amount (predetermined amount) LA. The consumption command is a command for causing the FC module 24 to generate power until the hydrogen amount in the tank unit 21 becomes equal to or less than the lower limit amount LA. Furthermore, the FC system ECU 71 also has a function of calculating the power that can be generated by the FC module 24 (power generation available power) when hydrogen is used until the amount of hydrogen in the tank unit 21 becomes equal to or less than the lower limit LA from the current amount. Note that the lower limit LA is an amount at which it can be determined that the hydrogen in the tank unit 21 is almost used up, and is an amount at which it can be determined that the inside of the tank unit 21 is almost empty.

[0054] The FC system ECU 71 obtains the power generation available power based on the output of the pressure sensor 53 and the output of the temperature sensor 54. The FC system ECU 71 stores a database in which the output of the pressure sensor 53 (or the amount of hydrogen in the tank unit 21), the output of the temperature sensor 54 (or the temperature), and the power generation available power are associated. When the FC system ECU 71 acquires the output of the pressure sensor 53 and the output of the temperature sensor 54, it refers to the database to obtain the power generation available power. The FC system ECU 71 may obtain the power generation available power using the output of the pressure sensor 53, or may obtain the power generation available power using the amount of hydrogen in the tank unit 21 obtained from the output of the pressure sensor 53. The FC system ECU 71 may constantly obtain the power generation available power, or may obtain the power generation available power when there is a need to output it.

[0055] The FC display panel 72 is connected to the FC system ECU 71. The FC display panel 72 displays and outputs various information indicating the operating state of the FC power generation system. Also, the FC display panel 72 has a function as an output device that outputs the power generation available power. The FC display panel 72 can output the power generation available power by displaying a numerical value on the panel or by voice notification. The FC display panel 72 is provided at the driver's seat 15. Therefore, the FC display panel 72 outputs the power generation available power to the passengers.

[0056] The operating device 75 includes an operating member for adjusting the output of the work vehicle 1 such as an accelerator pedal or an accelerator lever. The display switch 76 and the exhaustion switch 77 are provided at the driver's seat 15. Therefore, the display switch 76 and the exhaustion switch 77 are switches that receive operation inputs from the passengers. The operating device 75, the display switch 76, and the exhaustion switch 77 are connected to the main ECU 73. The main ECU 73 has a function of controlling each part of the work vehicle 1 according to operation inputs from the passengers. The control performed by the main ECU 73 includes control related to the movement of the work vehicle 1 and control related to the working device 335. The main ECU 73 generates a control command to be given to the inverter 62 based on the operation input received by the operating device 75. The inverter 62 controls the motor 31 according to the control command. Also, when the main ECU 73 receives an operation input via the display switch 76, it has a function of giving an instruction to the FC system ECU 71 to output the generable power to the FC display panel 72. That is, the display switch 76 (the first operation member) and the main ECU 73 constitute an operation part for outputting the generable power to the FC display panel 72.

[0057] Furthermore, when the main ECU 73 receives an operation input via the exhaustion switch 77, it also has a function of outputting a consumption command to the FC system ECU 71. That is, the exhaustion switch 77 (the second operation member) and the main ECU 73 constitute an operation part for outputting the consumption command to the FC system ECU 71 (the control device).

[0058] The main display panel 74 is connected to the main ECU 73. The main display panel 74 displays and outputs various information indicating the states of each part of the work vehicle 1. The main display panel 74 is provided at the driver's seat 15. Therefore, the main display panel 74 outputs toward the passengers.

[0059] 〔Regarding the consumption process〕 The consumption process is executed by the cooperation of the FC system ECU 71 and the main ECU 73 included in the control unit 70. FIG. 6 is a flowchart showing an example of consumption processing. In FIG. 6, first, the main ECU 73 determines whether an operation input has been received by the display switch 76 (step S1). The main ECU 73 repeats step S1 until it determines that an operation input has been received by the display switch 76. When it is determined that an operation input has been received by the display switch 76, the main ECU 73 gives a display command to the FC system ECU 71. The FC system ECU 71 that has received the display command displays and outputs the current available power to the FC display panel 72 (step S2). Note that the main ECU 73 restricts the reception of operation inputs of the depletion switch 77 until the current available power is displayed and output.

[0060] When the available power is displayed and output, next, the main ECU 73 determines whether an operation input has been received by the depletion switch 77 (step S3). If it is determined that no operation input has been received by the depletion switch 77, the main ECU 73 determines whether a predetermined time has elapsed since the available power was output (step S4). If it is determined that the predetermined time has not elapsed, the main ECU 73 returns to step S3 and repeats the process. If it is determined that the predetermined time has elapsed, the main ECU 73 returns to step S1. In this case, the main ECU 73 waits again for an operation input by the display switch 76 without performing the processes after step S3 (step S1). Thereby, after outputting the available power, it is possible to suppress an increase in the difference between the displayed available power and the actual available power due to the consumption of hydrogen in the tank unit 21.

[0061] When it is determined in step S3 that an operation input is received by the exhaustion switch 77, the main ECU 73 determines whether the amount of hydrogen in the tank unit 21 is equal to or less than a threshold Th (step S5). As described above, the amount of hydrogen in the tank unit 21 is obtained based on the output of the pressure sensor 53. Here, the threshold Th is set to a value that is greater than the lower limit amount LA and less than the amount of hydrogen corresponding to the power generation possible power according to the power storage possible power of the battery unit 30. Thereby, when the FC module 24 is caused to generate power until the amount of hydrogen in the tank unit 21 becomes equal to or less than the lower limit amount LA by subsequent processing, the generated power can be stored in the battery unit 30.

[0062] When it is determined in step S5 that the amount of hydrogen in the tank unit 21 is not less than the threshold Th, the main ECU 73 ends the process. In this case, the amount of hydrogen in the tank unit 21 is not small. Therefore, the main ECU 73 aborts the consumption process, which is a process of forcibly consuming hydrogen. This is because there is a risk of wasting the hydrogen in the tank unit 21.

[0063] On the other hand, when it is determined in step S5 that the amount of hydrogen in the tank unit 21 is less than or equal to the threshold Th, the main ECU 73 outputs a consumption command to the FC system ECU 71 (step S6). Thereby, the FC system ECU 71 acquires the consumption command and starts power generation in the FC module 24.

[0064] The FC module 24 generates power using the hydrogen remaining in the tank unit 21. While the FC module 24 is generating power, the FC system ECU 71 monitors and controls each part of the FC power generation system. The FC system ECU 71 refers to the charge amount (SOC) of the battery pack 30A by the BMU 30A1 and determines whether the generated power can be charged to the battery pack 30A. When it is determined that the battery pack 30A can be charged, the FC system ECU 71 stores the power generated by the FC module 24 in the battery pack 30A.

[0065] When the battery pack 30A is fully charged, the FC system ECU 71 operates the first DC / DC converter 64 to convert the power generated by the FC module 24 into a first voltage and store it in the lead-acid battery 63 and the auxiliary storage battery 67. Thus, in this embodiment, even when the battery pack 30A is fully charged, the power obtained from the hydrogen remaining in the tank unit 21 can be stored in the lead-acid battery 63 and the auxiliary storage battery 67.

[0066] At this time, if an external device is connected to the external output unit 66, the power from the first DC / DC converter 64 is output to the external device. In this case, even when the battery pack 30A is fully charged, the power obtained from the hydrogen remaining in the tank unit 21 can be consumed by the external device.

[0067] Note that when no external device is connected to the external output unit 66, the FC system ECU 71 keeps the switch 63a (Fig. 4) open, and when an external device is connected to the external output unit 66, the FC system ECU 71 switches the switch 63a from the open state to the closed state. Therefore, it is possible to suppress the power stored in the lead-acid battery 63 from being output to the external device. This is because the power stored in the lead-acid battery 63 is for the auxiliary equipment of the work vehicle 1, and it is not preferable to discharge it to the outside wastefully.

[0068] When no external device is connected to the external output unit 66, the power generated by the FC module 24 is stored in the lead-acid battery 63 and the auxiliary storage battery 67. Also, when an external device is connected to the external output unit 66, the power generated by the FC module 24 and the power stored in the auxiliary storage battery 67 are output to the external device.

[0069] As described above, based on the consumption command, the power generated by the FC module 24 is stored in the battery pack 30A, the lead-acid battery 63, and the auxiliary storage battery 67, or output to the external device.

[0070] The FC system ECU 71 that has started power generation in the FC module 24 based on the consumption command proceeds to step S7 and repeatedly determines whether the amount of hydrogen in the tank unit 21 is equal to or less than the lower limit LA. When it is determined that the amount of hydrogen in the tank unit 21 is equal to or less than the lower limit LA, the FC system ECU 71 stops the power generation by the FC module 24 (step S8) and ends the process. Therefore, when the FC module 24 acquires a consumption command, the FC module 24 generates power until the amount of hydrogen in the tank unit 21 becomes equal to or less than the lower limit (predetermined amount) LA.

[0071] According to the above configuration, when the FC system ECU 71 (control device) acquires a consumption command, the FC module 24 generates power until the amount of hydrogen in the tank unit 21 becomes equal to or less than the lower limit LA. In other words, when the FC module 24 acquires a consumption command, it starts power generation and stops power generation when the amount of hydrogen in the tank unit 21 becomes equal to or less than the lower limit LA. For this reason, for example, when the work vehicle 1 is stopped for a long period of time, the hydrogen remaining in the tank unit 21 can be consumed until it becomes equal to or less than the lower limit LA, and the amount of hydrogen in the tank unit 21 of the work vehicle 1 that is stopped for a long period of time can be reduced.

[0072] When a large amount of hydrogen remains in the tank unit 21 of the work vehicle 1 that is stopped for a long period of time, it may not be preferable in terms of hydrogen management. In this regard, according to the present embodiment, the amount of hydrogen in the tank unit 21 can be reduced, and the tank unit 21 can be made empty. If the tank unit 21 is in an empty state, there is no need to manage hydrogen. In this way, the hydrogen remaining in the tank unit 21 can be appropriately processed.

[0073] Further, since the work vehicle 1 of the present embodiment further includes a main ECU 73 (operation unit) that outputs a consumption command to the FC system ECU 71 when receiving an operation input via an exhaustion switch 77 (second operation member) (step S3), the hydrogen remaining in the tank unit 21 can be consumed by the FC module 24 until it reaches the lower limit amount LA or less by an operation input from an external source such as an occupant.

[0074] In addition, in the present embodiment, the process of outputting the consumption command performed by the main ECU 73 to the FC system ECU 71 is executed when the operation input is received via the exhaustion switch 77 and when the hydrogen amount in the tank unit 21 is equal to or less than the threshold value Th. Therefore, it is possible to suppress the output of the consumption command when a large amount of hydrogen remains in the tank unit 21, and to suppress the unnecessary consumption of the hydrogen in the tank unit 21. That is, if a large amount of hydrogen remains in the tank unit 21, the tank unit 21 can be removed from the work vehicle 1, and the remaining hydrogen can be stored together with the tank unit 21. On the other hand, in the present embodiment, when a small amount of hydrogen that is not enough to store the entire tank unit 21 remains in the tank unit 21, the remaining hydrogen can be consumed by the FC module 24 and used as electric power.

[0075] Therefore, the threshold value Th is set to a value that can determine a small amount of hydrogen that is not enough to store the entire tank unit 21. The threshold value Th is at least a value larger than the lower limit amount LA. In this case, by the consumption process, hydrogen is consumed by the difference between the threshold value Th and the lower limit amount LA.

[0076] Further, the FC system ECU 71 of the present embodiment calculates the electric power (generable electric power) that the FC module 24 can generate when using hydrogen until the hydrogen amount in the tank unit 21 reaches the lower limit amount LA from the current amount. Therefore, if necessary, the hydrogen amount in the tank unit 21 can be output to the outside as electric power. As a result, it becomes possible to appropriately grasp the amount of hydrogen in the tank unit 21.

[0077] In the present embodiment, the generable power calculated by the FC system ECU 71 is output by the FC display panel 72 (output device). In the present embodiment, when the main ECU 73 (operation unit) receives an operation input via the display switch 76 (first operation member) (step S1), it causes the FC system ECU 71 to execute the output of the generable power by the FC display panel 72 (step S2). Therefore, the generable power can be output to the occupant according to the request of the occupant.

[0078] Further, after causing the FC display panel 72 to output the generable power, when the main ECU 73 of the present embodiment receives an operation input via the exhaustion switch 77, it outputs a consumption command to the FC system ECU 71. Therefore, after allowing the occupant to grasp the amount of hydrogen in the tank unit 21, the occupant can be made to determine whether or not to operate the exhaustion switch 77. As a result, the remaining hydrogen in the tank unit 21 can be processed more appropriately.

[0079] 〔Others〕 It should be considered that all the embodiments disclosed this time are illustrative in all respects and not restrictive. In the above embodiment, the case where the process of consuming the hydrogen in the tank unit 21 by the FC module 24 is performed after the generable power is displayed and output is illustrated. However, the work vehicle 1 can also be configured without performing the process of causing the FC module 24 to consume hydrogen.

[0080] In the above embodiment, the case where the fuel of the FC module 24 is hydrogen is illustrated. However, the fuel of the FC module 24 may be one that generates electric power using methane or carbon monoxide. In this case, hydrogen in the above embodiment may be read as methane or carbon monoxide.

[0081] The scope of the present invention is not defined by the above description, but is indicated by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

Explanation of Signs

[0082] 1 Work vehicle 11 Vehicle body 12 Travel device 12A Front wheel 12B Rear wheel 13 Hydrogen tank 14 Driving device 15 Driver's seat 16 Cabin 17 Mounting frame 17A Ceiling frame 17B Pillar 17C Reinforcing frame 21 Tank unit 22 Pipe 22A Pipe section 22B Pipe section 24 FC module 24a Fuel cell stack 24b Boost circuit 24c ECU 25 Circuit 30 Battery unit 30A Battery pack 31 Electric motor 32 Front frame 33 Transmission case 33a Power transmission mechanism 34 Bonnet 37 Support frame 41 Chassis 44 Connecting device 44A Upper arm 44B Lower arm 48 First radiator 49 Second radiator 50 On-off valve 51 Valve unit 52 Filling port 53 Pressure sensor 54 Temperature sensor 62 Inverter 62a ECU 63 Lead-acid battery 63a Switch 64 First DC / DC converter 64a ECU 65 Second DC / DC converter 65a ECU 66 External output section 67 Auxiliary storage battery 70 Control unit 71 FC system ECU 72 FC display panel 73 Main ECU 74 Main display panel 75 Operating device 76 Display switch 77 Exhaustion switch 111 Cover 334 PTO shaft 335 Working device

Claims

1. A fuel cell, a motor driven by electric power output from the fuel cell, a hydrogen tank for storing hydrogen which is fuel of the fuel cell, and a control device that calculates the generable electric power of the fuel cell when hydrogen is used until the hydrogen amount in the hydrogen tank reaches a predetermined amount from the current amount. A work vehicle.

2. The work vehicle according to claim 1, further comprising an output device that outputs the generable electric power calculated by the control device.

3. The work vehicle according to claim 2, further comprising an operation unit that causes the output device to output the generable electric power when receiving an operation input via a first operation member.

4. The control device can acquire a consumption command, when the control device acquires the consumption command, the fuel cell generates power until the hydrogen amount in the hydrogen tank becomes equal to or less than the predetermined amount, after the operation unit causes the output device to output the generable electric power, when receiving an operation input via a second operation member, the operation unit outputs the consumption command to the control device. The work vehicle according to claim 3.

5. The work vehicle according to claim 4, further comprising a power storage device that stores the electric power generated by the fuel cell. When the consumption command is acquired, the electric power generated by the fuel cell is stored in the power storage device.

6. The work vehicle according to claim 5, further comprising an auxiliary power storage device. When the power storage device is fully charged, the electric power generated by the fuel cell is stored in the auxiliary power storage device.

7. The work vehicle according to claim 5, further comprising an external output unit that outputs the electric power generated by the fuel cell to the outside. When the power storage device is fully charged, the electric power generated by the fuel cell is output to an external device connected to the external output unit. The work vehicle according to claim 5.

8. The work vehicle according to claim 6, further comprising a display unit that displays a remaining amount of hydrogen in the hydrogen tank.

9. The work vehicle according to claim 7, further comprising an alarm unit that issues an alarm when the hydrogen amount in the hydrogen tank becomes equal to or less than a warning amount.

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