Fuel cell vehicle

Abstract

To provide a fuel cell vehicle which enables tanks having different capacities to be filled sufficiently.SOLUTION: A vehicle 1 includes: a plurality of tanks 7a to 7d for storing hydrogen; and a fuel cell system 3 which uses hydrogen stored in the tanks to generate electric power. The vehicle 1 further includes: a filling fuel pipe 9 and a part of a fuel pipe 10 which are branched from a fuel supply port 8 provided at a vehicle body to be connected to the tanks 7a to 7d and guide the hydrogen from the fuel supply port 8 to the tanks; a fuel pipe 10 which extends from the tank 7a to 7d to be joined and connected to the fuel cell system 3 and guides the hydrogen from the tanks to the fuel cell system 3; branched pipe on / off valves 15a to 15d respectively provided at branched passages of the fuel pipe 10; and a fuel cell control unit 20a which controls the branched pipe on / off valves 15a to 15d. The tank to be filled with the hydrogen from the fuel supply port 8 can be selected from the tanks 7a to 7d through control by the fuel cell control unit 20a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fuel cell vehicle equipped with a tank filled with gaseous fuel. [Background technology]

[0002] Fuel cell vehicles are equipped with a fuel cell system that generates electricity by reacting hydrogen (gaseous fuel) supplied from an on-board tank with air. In fuel cell vehicles, it is possible to extend the driving range by increasing the capacity of the tank, but due to limited installation space, it is difficult to increase the size of the tank. In recent years, attempts have been made to increase the overall tank capacity by installing multiple small tanks with excellent mountability, thereby making effective use of the available space in the vehicle.

[0003] For example, Patent Document 1 discloses a fuel cell vehicle equipped with multiple hydrogen storage tanks. Furthermore, in Patent Document 1, when filling each tank with hydrogen, the operation of a filling device connected to each tank is controlled based on the internal temperature and pressure of each fuel tank in order to increase the filling rate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-107351 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, since the amount of available space in a vehicle is not constant, if one tries to make the most of the available space by installing multiple small tanks, the size (capacity) of each tank may end up being different. In Patent Document 1, hydrogen is filled into each tank using a different filling device, which requires multiple filling devices, making it difficult to apply the method to vehicles equipped with multiple tanks.

[0006] Therefore, it is common to configure the vehicle so that hydrogen supplied from an external source is divided inside the vehicle and supplied to each tank. However, when a plurality of tanks of different capacities are filled with hydrogen at the same time, some of the plurality of tanks will be filled to capacity first. To increase the amount of hydrogen that can be stored, the tank can be filled with hydrogen at high pressure. However, because the temperature inside the tank rises due to the heat of compression, most vehicles equipped with a tank for storing hydrogen are equipped with a safety device that stops filling the tank with hydrogen based on the temperature inside the tank to prevent overfilling.

[0007] Therefore, if some of the multiple tanks become full as described above and refilling continues in order to refill the other tanks, the temperature will rise in the full tank, causing the safety device to stop refilling, resulting in the problem that a large amount of hydrogen can not be secured for the vehicle as a whole. The present invention has been made in view of the above problems, and has an object to provide a fuel cell vehicle that enables sufficient filling of a plurality of tanks with different capacities. [Means for solving the problem]

[0008] In order to achieve the above-mentioned objective, the fuel cell vehicle of the present invention is a fuel cell vehicle equipped with a plurality of tanks for storing gaseous fuel and a fuel cell system that generates electricity using the gaseous fuel stored in the tanks, and is characterized in that it comprises a first fuel pipe that branches off from a fuel supply port provided on the vehicle body and connects to the plurality of tanks, and guides the gaseous fuel supplied from the fuel supply port to the plurality of tanks, a second fuel pipe that joins up from the plurality of tanks and connects to the fuel cell system, and guides the gaseous fuel from the plurality of tanks to the fuel cell system, first opening and closing valves provided in each branch of the first fuel pipe, and a control unit that controls the first opening and closing valves, and which makes it possible to select a tank from the plurality of tanks to be filled with gaseous fuel from the fuel supply port by control of the first opening and closing valves by the control unit. Effect of the Invention

[0009] The fuel cell vehicle of the present invention can select and limit the tanks that can be filled with gaseous fuel from among the multiple tanks mounted on the vehicle, making it possible to fill only tanks that have a small amount of gaseous fuel, for example. This makes it possible to appropriately fill each of the multiple tanks mounted on the vehicle with gaseous fuel using a single filling device, thereby increasing the total amount of gaseous fuel that can be filled. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram of a power system of a fuel cell vehicle according to an embodiment of the present invention. [Diagram 2] 5 is a flowchart showing a part of a control procedure for an on-off valve during operation in this embodiment. [Diagram 3] 10 is a flowchart showing the remaining steps of the control procedure for the on-off valve during operation in this embodiment. [Figure 4] 5 is a flowchart showing a control procedure of the on-off valve during filling in the present embodiment. [Diagram 5] FIG. 2 is an explanatory diagram showing an image of filling each tank with hydrogen in this embodiment. [Figure 6] FIG. 13 is an explanatory diagram showing an image of filling each tank with hydrogen in a conventional example. [Figure 7] 4 is a graph showing an example of the transition of the amount of hydrogen filled during hydrogen filling. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a fuel cell vehicle according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram of a power system of a fuel cell vehicle according to this embodiment. The fuel cell vehicle (hereinafter referred to as vehicle 1) of this embodiment includes a fuel cell system 3 that generates electricity using hydrogen as fuel, a battery 4, and a motor 5. Electricity generated by the fuel cell system 3 is supplied to the motor 5 directly or via the battery 4, and the motor 5 drives drive wheels 6 of the vehicle 1.

[0012] A plurality of (four) tanks 7a, 7b, 7c, and 7d for storing hydrogen (gaseous fuel) are mounted on the vehicle 1. The four tanks 7a to 7d have different capacities. A fuel supply port 8 through which hydrogen is supplied from the outside is provided on the body of the vehicle 1. One end of a fuel filling pipe 9 through which fuel is supplied to each of the tanks 7a to 7d is connected to the fuel supply port 8.

[0013] Hydrogen is supplied from each of the tanks 7a, 7b, 7c, and 7d to a fuel cell system 3 mounted on the vehicle 1 via a fuel pipe 10. The fuel pipe 10 extends from each of the tanks 7a, 7b, 7c, and 7d, joins together, and is connected to the fuel cell system 3. The other end of the fuel filling pipe 9 is connected between the junction of branch pipes from each of the tanks 7a-7d of the fuel pipe 10 and the fuel cell system 3 (connection part 10a). The fuel filling pipe 9 and the parts of the fuel pipe 10 between each of the tanks 7a-7d and the connection part 10a correspond to the first fuel pipe of the present invention that introduces fuel (hydrogen) from the fuel supply port 8 to each of the tanks 7a-7d. The fuel pipe 10 corresponds to the second fuel pipe of the present invention that introduces fuel from each of the tanks 7a-7d to the fuel cell system 3.

[0014] The fuel cell system 3 introduces air through an air introduction system 11 and generates electricity by reacting hydrogen with oxygen in the air. Hydrogen that has not reacted in the fuel cell system 3 is returned to the fuel cell system 3 via a hydrogen recirculation system 12 and reused. Water and water vapor generated by the reaction of hydrogen in the fuel cell system 3 are exhausted from an exhaust pipe 13 to the outside of the vehicle.

[0015] Branch pipe on-off valves 15a, 15b, 15c, and 15d (first on-off valve, second on-off valve) are provided at each branch pipe of the fuel pipe 10. In addition, the filling fuel pipe 9 is provided with a filling on-off valve 16a, and a supply on-off valve 16b is provided between the connection part 10a of the fuel pipe 10 and the fuel cell system 3. The branch pipe on-off valves 15a to 15d, the filling on-off valve 16a, and the supply on-off valve 16b are independently controlled by a control unit 20.

[0016] The vehicle 1 is also provided with a pressure sensor 17 (tank internal pressure detection unit) that detects the internal pressure of each of the tanks 7a to 7d. The detection value of the pressure sensor 17 is input to the control unit 20. A selection switch 21 (selection unit) for selecting a part of the multiple tanks 7a to 7d to be used preferentially is provided near the driver's seat of the vehicle 1. The selection switch 21 may be capable of selecting one of the multiple tanks 7a to 7d, or may be capable of selecting a plurality of tanks (for example, two). Operation information of the selection switch 21 is input to the control unit 20.

[0017] The control unit 20 is a control device that performs overall control of the vehicle 1, including the motor 5, and is configured to include an input / output device, a memory device (ROM, RAM, non-volatile RAM, etc.), a timer, a central processing unit (CPU), etc. The control unit 20 (required output acquisition unit) calculates the required output W of the motor 5 based on the accelerator operation amount of the vehicle 1, etc., and controls the drive of the motor 5.

[0018] The control unit 20 also includes a fuel cell control section 20a that controls the fuel cell system 3, the branch pipe on-off valves 15a, 15b, 15c, and 15d, the filling on-off valve 16a, and the supply on-off valve 16b. The fuel cell control unit 20a inputs the charging rate of the battery 4 from the battery monitoring unit 4a, which monitors the charging state of the battery 4, as well as the required output W of the motor 5, and controls the output power in the fuel cell system 3 based on the required output W, the charging rate of the battery 4, etc.

[0019] In addition, the fuel cell control unit 20a inputs the internal temperature of each tank 7a-7d using a temperature sensor (not shown), and is equipped with a safety device that stops filling of hydrogen into the tanks 7a-7d if the internal temperature of any tank approaches the allowable upper limit value. Furthermore, the fuel cell control unit 20a receives the required output W, the internal pressures of the tanks 7a-7d input from the pressure sensor 17, and the selection made by the selection switch 21, and controls the on-off valves 15a-15d, 16a, and 16b. The fuel cell control unit 20a may be provided in the vehicle 1 as a separate entity from the control unit 20.

[0020] 2 and 3 are flowcharts showing the control procedure for the branch pipe on-off valves 15a to 15d executed by the fuel cell control unit 20a during operation of the fuel cell system 3. During operation of the fuel cell system 3, the fuel cell control unit 20a closes the filling on-off valve 16a and opens the supply on-off valve 16b. This routine is repeatedly executed at predetermined time intervals, for example, when the vehicle power source is turned on.

[0021] 2 and 3, first, in step S10, the required output W and operation information of the selection switch 21 are input from the control unit 20. Then, the process proceeds to step S20. In step S20, the remaining hydrogen amount in each of the tanks 7a-7d is confirmed (estimated) based on the internal pressure of each of the tanks 7a-7d input from the pressure sensor 17. The remaining hydrogen amount in each of the tanks 7a-7d may be calculated, for example, based on the internal pressure and capacity of the tanks 7a-7d. Furthermore, the remaining hydrogen amount in each of the tanks 7a-7d is added together to calculate the total remaining hydrogen amount (tank remaining amount V) of all the tanks 7a-7d. Then, the process proceeds to step 30.

[0022] In step S30, it is determined whether the required output W input in step S10 is equal to or greater than a predetermined value W1. The predetermined value W1 may be set to a value close to the minimum output of the fuel cell system 3 that requires hydrogen to be supplied from all of the tanks 7a-7d. If the required output W is equal to or greater than the predetermined value W1, the process proceeds to step S40. If the required output W is less than the predetermined value W1, the process proceeds to step S70.

[0023] In step S40, it is determined that all of the tanks 7a to 7d are to be used, and the process proceeds to step S50. In step S50, all of the branch pipe opening / closing valves 15a to 15d are opened, and the process proceeds to step S60. In step S60, hydrogen is introduced from all of the tanks 7a to 7d into the fuel cell system 3 to generate electricity, and then the main routine is returned.

[0024] In step S70, it is determined whether the tank remaining amount V estimated in step S20 is equal to or greater than a predetermined value V1. If it is equal to or greater than the predetermined value V1, the process proceeds to step S80. If the tank remaining amount V is less than the predetermined value V1, the process proceeds to step S40. The predetermined value V1 may be, for example, The tank residual amount V may be appropriately set near the lower limit value such that sufficient output (for example, maximum output of the fuel cell system 3) cannot be obtained in the fuel cell system 3 unless all of the tanks 7a to 7d are used.

[0025] In step S80, it is determined whether the remaining tank amount V calculated in step S20 is less than a predetermined value V2, and if it is less than the predetermined value V2, the process proceeds to step S100. If the remaining tank amount V is equal to or greater than the predetermined value V2, the process proceeds to step S90. The predetermined value V2 may be set appropriately to a value greater than the predetermined value V1. In step S90, it is determined that one tank will be used. The tank to be used is the tank selected by the selection switch 21 from among the tanks 7a to 7d. If multiple tanks are selected by the selection switch 21, any one of the selected tanks will be used. If no tank to be used is selected by the selection switch 21, a tank that has been specified in advance (for example, the tank with the largest capacity) from among the multiple tanks 7a to 7d may be used. Then, the process proceeds to step S110.

[0026] In step S100, it is determined that multiple tanks will be used. The tanks to be used are two or more of the tanks 7a to 7d, but are less than the total number of tanks (for example, two). If one tank is selected by the selection switch 21, the tanks to be used will be multiple tanks including the selected tank, and if multiple tanks are selected, the selected tank will be used. Then, the process proceeds to step S110.

[0027] In step S110, the branch pipe opening / closing valves 15a to 15d corresponding to the tank to be used selected in step S90 or step S100 are opened, and the process proceeds to step S120. In step S120, hydrogen is introduced from one of the tanks 7a to 7d to be used into the fuel cell system 3. Then, the process proceeds to step S130.

[0028] In step S130, the internal pressure of the tank being used is input from the pressure sensor 17 as the residual hydrogen pressure P. Then, the process proceeds to step S140. In step S140, it is determined whether the residual hydrogen pressure P is equal to or less than a predetermined value P1. The predetermined value P1 may be set appropriately to a value that indicates the amount of hydrogen filled in the tank that is close to 0. If the residual hydrogen pressure P is equal to or less than the predetermined value P1, the process proceeds to step S150. If the residual hydrogen pressure P is greater than the predetermined value P1, the process returns to step S30.

[0029] In step S150, among the branch pipe on-off valves 15a to 15d, the branch pipe on-off valves 15a to 15d that are currently closed are additionally opened to add a tank to be used. The additional number of branch pipe on-off valves 15a to 15d that are opened is, for example, one. Then, the process proceeds to step S160 in FIG. 3. In step S160, the required output W is input from the control unit 20. Then, the process proceeds to step S170.

[0030] In step S170, it is determined whether the required output W input in step S160 is equal to or greater than a predetermined value W1. If the required output W is equal to or greater than the predetermined value W1, the process proceeds to step S180. If the required output W is less than the predetermined value W1, the process proceeds to step S200. In step S180, it is determined that all of the tanks 7a to 7d are to be used, and the process proceeds to step S190.

[0031] In step S190, all of the branch pipe opening / closing valves 15a to 15d are opened, and then the present routine is returned. In step S200, it is determined whether the required output W input in step S160 is equal to or less than a predetermined value W2. If the required output W is equal to or less than the predetermined value W2, the process proceeds to step S210. If the required output W is greater than the predetermined value W2, the process proceeds to step S220. The predetermined value W2 may be appropriately set to a value smaller than the predetermined value W1. In step S210, one additional branch pipe on-off valve 15a to 15d is opened so as to use one additional tank, and the process then returns to step S110.

[0032] In step S220, a plurality of (eg, two) additional branch pipe opening / closing valves 15a to 15d are opened so that a plurality of additional tanks are used, and the process then returns to step S110. 4 is a flowchart showing a control procedure for the branch pipe on-off valves 15a-15d executed by the fuel cell control unit 20a when the tanks 7a-7d are filled with fuel. When the tanks 7a-7d are filled with fuel, the fuel cell control unit 20a opens the filling on-off valve 16a and closes the supply on-off valve 16b.

[0033] 4, first, in step S300, operation information of the selection switch 21 is input from the control unit 20, and the remaining amount of hydrogen in each of the tanks 7a-7d is confirmed based on the internal pressure and volume of each of the tanks 7a-7d input from the pressure sensor 17. Furthermore, the remaining amounts of hydrogen in each of the tanks 7a-7d are added together to calculate the remaining amount of hydrogen in all of the tanks 7a-7d (remaining tank amount V). Then, the process proceeds to step 310.

[0034] In step S310, it is determined whether the remaining tank volume V calculated in step S300 is equal to or greater than a predetermined value V1, and if it is equal to or greater than the predetermined value V1, the process proceeds to step S320. If the remaining tank volume V is less than the predetermined value V1, the process proceeds to step S360. In step S320, it is determined whether the remaining tank amount V calculated in step S300 is less than a predetermined value V2, and if it is less than the predetermined value V2, the process proceeds to step S330. If the remaining tank amount V is equal to or greater than the predetermined value V2, the process proceeds to step S340.

[0035] In step S330, it is determined that multiple tanks are to be filled. The tanks to be filled are two or more of the tanks 7a to 7d, but are fewer than the total number of tanks (for example, two). If one tank is selected by the selection switch 21, the tanks to be filled are multiple tanks including the selected tank, and if multiple tanks are selected, the selected tank is the tank to be filled. Then, the process proceeds to step S350.

[0036] In step S340, it is determined that one tank is to be filled. The tank to be filled is the tank selected by the selection switch 21 from among the tanks 7a to 7d. If no tank is selected by the selection switch 21, the tank with the lowest internal pressure among the multiple tanks 7a to 7d is selected. Then, the process proceeds to step S350. In step S350, the branch pipe opening / closing valves 15a to 15d corresponding to the tank selected in step S330 or step S340 are opened, and the process proceeds to step S380.

[0037] In step S360, it is determined that all of the tanks 7a to 7d are to be filled, and the process proceeds to step S370. In step S370, all of the branch pipe opening / closing valves 15a to 15d are opened, and the process proceeds to step S380. In step S380, hydrogen is introduced from the outside by the hydrogen injector 30 and filled into the tank to be used, and the process then proceeds to step S390.

[0038] In step S390, the residual hydrogen pressure in each of the tanks 7a to 7d, that is, the internal pressure of each of the tanks 7a to 7d input from the pressure sensor 17, is confirmed. Then, the process proceeds to step S400. In step S400, it is determined whether the tanks filled with hydrogen are full (full) based on the residual hydrogen pressure in each of the tanks 7a-7d confirmed in step S390. If the tanks filled with hydrogen are full, the process proceeds to step S410. If the tanks filled with hydrogen are not full, the process returns to step S380.

[0039] In step S410, it is determined whether or not tanks other than the tank filled with hydrogen (other tanks) have also been filled, that is, whether or not the hydrogen pressure in all tanks 7a to 7d is full. If the other tanks have also been filled, this routine ends. If the other tanks have not been filled, the process returns to step S300. The vehicle 1 of this embodiment is equipped with a plurality of tanks 7a-7d of different capacities for storing hydrogen, and the branch pipes of the fuel pipe 10 connecting each of the tanks 7a-7d to the fuel cell system 3 have branch pipe on-off valves 15a-15d, respectively, which are independently controlled to be opened and closed by the fuel cell control unit 20a of the control unit 20. Therefore, the number of tanks to be used among the tanks 7a-7d can be arbitrarily switched by the control of the fuel cell control unit 20a.

[0040] 5, the fuel cell control unit 20a opens some of the branch pipe on-off valves 15a-15d, closes the filling on-off valve 16a, and opens the supply on-off valve 16b, thereby allowing hydrogen to be supplied from some of the tanks 7a-7d to the fuel cell system 3 to generate power (during operation). Also, as shown in FIG. 5, the fuel cell control unit 20a opens some of the branch pipe on-off valves 15a-15d, opens the filling on-off valve 16a, and closes the supply on-off valve 16b, thereby allowing hydrogen to be filled into some of the tanks 7a-7d (during filling).

[0041] In a vehicle that uses all of the tanks 7a-7d at all times, for example a vehicle that is not equipped with branch pipe on-off valves 15a-15d, the amount of hydrogen filled in all of the tanks 7a-7d decreases during operation, i.e., when power is being generated by the fuel cell system 3, as shown in FIG. 6, and during refilling, all of the tanks 7a-7d are filled with hydrogen. Figure 7 is a graph showing examples of the progress of the total hydrogen filling amount (remaining tank amount V) when hydrogen is filled from the same total filling amount as in this embodiment in which one of the tanks 7a-7d is filled from its used state (pattern A), when hydrogen is filled from multiple (two) of the tanks 7a-7d from their used states (pattern B), and when hydrogen is filled from all of the tanks 7a-7d from their used states (pattern C), as well as an example of the progress of the total hydrogen filling amount when hydrogen is filled from the same total filling amount as in this embodiment in a conventional example in which all of the tanks 7a-7d are used.

[0042] As shown by the dashed line in Figure 7, in the conventional example in which all tanks 7a-7d are used, in all of Pattern A, Pattern B, and Pattern C, all of the tanks 7a-7d are filled with hydrogen, and each time filling of at least one of the multiple tanks 7a-7d of different capacities is completed, the temperature of that tank rises and filling is stopped by a safety device, and then filling is resumed after the temperature of that tank has dropped.

[0043] In contrast, in this embodiment, as shown by the solid line in pattern A of Figure 7, when the remaining tank amount V is large (greater than or equal to the predetermined value V1), one of the tanks 7a-7d is used, and only this one tank is filled with hydrogen. Therefore, since filling is not stopped before all of the tanks 7a-7d are completely filled, filling is stopped every time at least one of the tanks 7a-7d is completely filled (shown by the dashed line in pattern A), the number of filling stops can be reduced compared to the conventional example, and the total filling time can be significantly shortened. As shown by the solid line in pattern B in Fig. 7, when the remaining tank capacity V is equal to or greater than V1 and less than V2, multiple (2) tanks 7a-7d are in use, and hydrogen is filled into the multiple (2) tanks in use. Therefore, when one of the two tanks is filled to capacity and the temperature rises, filling is stopped, but since filling is completed for all of the tanks 7a-7d with at most one filling stop, the number of filling stops can be reduced compared to the conventional example shown by the dashed line in pattern B, and the total filling time can be shortened.

[0044] As shown in pattern C of Figure 7, when the remaining tank amount V is less than V2, in this embodiment, as in the conventional example, hydrogen is filled into all of the tanks 7a to 7d, so the total filling time is the same in this embodiment and the conventional example. As described above, in this embodiment, the branch pipe on-off valves 15a-15d can be individually controlled to open and close, so that it is possible to select a tank to be filled with hydrogen from among the multiple tanks 7a-7d mounted on the vehicle 1. This makes it possible to sufficiently fill each of the tanks 7a-7d, which have different capacities, and increases the total amount of hydrogen filled in the tanks 7a-7d, thereby increasing the following distance of the vehicle 1.

[0045] Furthermore, by filling only some of the tanks, the frequency of tanks whose temperature rises excessively during filling can be reduced compared to filling all of the tanks 7a-7d with hydrogen. This reduces the number of times that filling is stopped by safety devices due to temperature rises in the tanks, and shortens the total filling time. Furthermore, when using hydrogen in the tanks 7a to 7d, the pressure in the tanks to be used can be significantly reduced by limiting the tanks to be used to some of the tanks, compared to using all of the tanks 7a to 7d, and therefore the efficiency of filling the tanks with hydrogen can be improved.

[0046] The control unit 20 controls the number of tanks to be used so that it varies according to the required output W. In detail, when the required output W is equal to or less than a predetermined value W2, one tank 7a-7d is added to the number of tanks 7a-7d to be used, when the required output W exceeds the predetermined value W2, the number of tanks 7a-7d to be used is increased by two or more, and when the required output W is equal to or more than the predetermined value W1, all of the tanks 7a-7d are used. As a result, a sufficient amount of hydrogen is supplied to the fuel cell system 3 in response to the required output W, and the required output W is ensured, while the number of tanks used can be reduced.

[0047] In particular, in vehicles such as range extender type fuel cell vehicles in which the amount of fuel used in the fuel cell system 3 is constant, small and stable, there are more opportunities to limit the number of tanks used, which increases the opportunities to shorten the filling time. The fuel cell control unit 20a changes the number of branch pipe on-off valves 15a-15d to open based on the tank remaining capacity V, which is the amount of hydrogen stored in the tanks 7a-7d, and the required output W. In more detail, when the tank remaining capacity V is less than V1 or the required output is equal to or greater than a predetermined value W1, all of the tanks 7a-7d are used, when the tank remaining capacity V is equal to or greater than V1 but less than V2, multiple of the tanks 7a-7d are used, and when the tank remaining capacity is V2 or greater, one of the tanks 7a-7d is used. This allows hydrogen to be supplied to the fuel cell system 3 in an adequate amount according to the required output, while limiting the number of tanks to be used according to the fill state of the tanks 7a-7d.

[0048] On the other hand, the fuel cell control unit 20a changes the number of branch pipe opening / closing valves 15a to 15b to be opened based on the remaining amount V of hydrogen in the tank when filling the tank with hydrogen. Specifically, when the tank remaining amount V is less than V1, all of the tanks 7a-7d are filled, when the tank remaining amount V is equal to or greater than V1 but less than V2, multiple tanks 7a-7d are filled, and when the tank remaining amount V is equal to or greater than V2, one tank 7a-7d is filled. This allows the number of tanks to be filled to be set appropriately according to the filling state of the tanks 7a-7d, efficient filling is achieved in a low filling state, and the occurrence of tanks that become overfilled in a high filling state is suppressed, making it possible to fully fill all of the tanks 7a-7d and increasing the total filling amount.

[0049] The vehicle 1 is also provided with a selection switch 21 for selecting a tank to be used preferentially from among the plurality of tanks 7a to 7d. Therefore, by operating the selection switch 21, it is possible to select one of the branch pipe opening / closing valves 15a to 15d when the fuel cell control unit 20a opens a portion of the branch pipe opening / closing valves 15a to 15d based on the required output W and residual hydrogen pressure P.

[0050] For example, if a tank with a larger capacity is selected from among the multiple tanks 7a to 7d, the tank with the larger capacity will be used preferentially, making it less likely that the tank will be underfilled. Therefore, the number of tanks used can be reduced compared to selecting a tank with a smaller capacity, and the number of times the tank will be filled to full capacity afterwards can be reduced, reducing the frequency of filling stops due to temperature rise.

[0051] For example, if it is known in advance that the mileage will be short and the amount of hydrogen used will be small, the tank with the smallest capacity may be selected from among the tanks 7a to 7d. In this case, the tank with the smallest capacity will be used preferentially, and the tank internal pressure can be reduced relatively significantly immediately when fuel is used. This can increase the efficiency of hydrogen filling during subsequent filling.

[0052] Furthermore, the branch pipe opening / closing valves 15a-15d may be switched, for example, for each refilling opportunity when the fuel cell control unit 20a partially opens them based on the required output W and the residual hydrogen pressure P. This automatically switches the tank to be preferentially used, thereby preventing hydrogen from remaining in the tank not used preferentially for a long period of time when driving and refilling with low fuel consumption are repeated for a long period of time, and thus preventing deterioration of the hydrogen in the tank.

[0053] Furthermore, the fuel cell control unit 20a switches the number of tanks to be used based on the required output W and the remaining tank volume V (corresponding to the tank internal pressure), but it may be possible to limit the number of tanks to be used to one, for example, when hydrogen is scheduled to be filled in the near future. The driver can input the fact that hydrogen is scheduled to be filled in the near future by operating an operation unit provided in the vehicle 1.

[0054] The present invention is not limited to the above-described embodiment, and can be modified without departing from the spirit and scope of the invention. For example, in the above embodiment, the number of tanks to be used is switched between one and all of the tanks based on the remaining tank volume V and the required output W, but it may be switched between a plurality of tanks (for example, two) and all of the tanks.

[0055] In this embodiment, the fuel pipe (first fuel pipe) that guides the gaseous fuel supplied from the fuel supply port 8 to the multiple tanks 7a-7d and the fuel pipe (second fuel pipe) that guides the gaseous fuel from the multiple tanks 7a-7d to the fuel cell system 3 are configured to share a portion of the fuel pipe 10 between the tanks 7a-7d and the connection portion 10a, but the first fuel pipe and the second fuel pipe may be provided separately. In this case, branch pipe opening / closing valves 15a-15d are required for each branch pipe of the first fuel pipe and each branch pipe of the second fuel pipe, respectively.

[0056] The present invention can be widely applied to fuel cell vehicles equipped with a plurality of tanks for storing gaseous fuel. [Explanation of symbols]

[0057] 1 Vehicle (Fuel Cell Vehicle) 3. Fuel Cell System 7a, 7b, 7c, 7d tanks 8 Fuel supply port 9 Fuel piping for filling (1st fuel piping) 10 Fuel piping (2nd fuel piping, 1st fuel piping) 15a, 15b, 15c, 15d Branch pipe on-off valve (first on-off valve, second on-off valve) 17 Pressure sensor (tank internal pressure detection section) 20 Control unit (request output acquisition unit) 20a Fuel cell control unit (control unit) 21 Selection switch (selection section)

Claims

1. A fuel cell vehicle equipped with a plurality of tanks for storing gaseous fuel and a fuel cell system for generating electricity using the gaseous fuel stored in the tanks, a first fuel pipe that branches off from a fuel supply port provided on a vehicle body, connects to the plurality of tanks, and guides the gas fuel supplied from the fuel supply port to the plurality of tanks; a second fuel pipe that joins the plurality of tanks and connects to the fuel cell system, and guides the gas fuel from the plurality of tanks to the fuel cell system; a first on-off valve provided in each branch passage of the first fuel pipe; A control unit that controls the first on-off valve, The control unit controls the first opening / closing valve to select a tank to be filled with the gas fuel through the fuel supply port from among a plurality of tanks. A fuel cell vehicle characterized by:

2. a required output acquisition unit that acquires a required output from the fuel cell system; a second on-off valve provided in each branch passage of the second fuel pipe; The control unit acquires a required output of the fuel cell system, and controls the second opening / closing valve based on the required output to select a tank that uses gaseous fuel.

2. The fuel cell vehicle according to claim 1 .

3. a tank internal pressure detection unit that detects the internal pressure of each of the plurality of tanks; The control unit changes the number of the second on-off valves to be opened based on the internal pressure of the tank selected based on the required output and the required output.

3. The fuel cell vehicle according to claim 2.

4. A selection unit is provided for selecting the second on-off valves when the control unit is to open a part of the second on-off valves based on the required output and the internal pressure.

4. The fuel cell vehicle according to claim 3.

5. The control unit switches the second on-off valves when the control unit opens a part of the second on-off valves based on the required output and the internal pressure every time the gas fuel is filled into the tank.

4. The fuel cell vehicle according to claim 3.

6. a tank internal pressure detection unit that detects the internal pressure of each of the plurality of tanks; The control unit changes the number of the first on-off valves to be opened based on the internal pressure when the gas fuel is filled into the tank.

2. The fuel cell vehicle according to claim 1 .

Images