Hydrogen Supply System

Abstract

To obtain a constitution in which the supply of hydrogen to a fuel battery is continued even if direct supply is stopped for some reason, in the constitution which decompresses high-pressure hydrogen, and can directly supply it to the fuel battery.SOLUTION: A hydrogen supply system comprises: a pressure reducing valve which is supplied with high-pressure hydrogen, and pressure-reduces the high-pressure hydrogen; a pipe member in which a main flow passage for directly supplying low-pressure hydrogen which is pressure-reduced by the pressure reducing valve to a fuel battery; a branch pipe member which is branched from a middle portion of the main flow passage, and in which a branch flow passage for supplying the low-pressure hydrogen to a hydrogen storage part is formed; a merging pipe member in which a merging flow passage which is merged with a middle of the main flow passage from the hydrogen storage part is formed; one three-way valve arranged at a branch point of the merging flow passage; the other three-way valve arranged at the merging point of the merging flow passage; and a control part for controlling the opening / closing of one three-way valve and the other three-way valve.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a hydrogen supply system. [Background technology]

[0002] The hydrogen filling method described in Patent Document 1 involves providing a heat exchanger containing a hydrogen storage alloy between a hydrogen storage source and a low-pressure hydrogen tank, and filling the low-pressure hydrogen tank with hydrogen stored in the hydrogen storage source through the heat exchanger. The method includes the steps of releasing hydrogen from the hydrogen storage alloy and introducing the released hydrogen into the low-pressure hydrogen tank, and filling the low-pressure hydrogen tank with hydrogen stored in the hydrogen storage source while cooling it using the hydrogen storage alloy, which is cooled by an endothermic reaction when hydrogen is released from the hydrogen storage alloy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-303625 Summary of the Invention [Problem to be solved by the invention]

[0004] In a conventional off-site hydrogen system, which is an example of a hydrogen supply system, high-pressure hydrogen stored at a hydrogen station is reduced to low-pressure hydrogen and stored in a low-pressure hydrogen tank and a hydrogen storage alloy. The low-pressure hydrogen stored in the low-pressure hydrogen tank and the hydrogen storage alloy is then supplied to a fuel cell. This requires a large area for the low-pressure hydrogen tank and the hydrogen storage alloy.

[0005] On the other hand, if high-pressure hydrogen stored at a hydrogen station is reduced in pressure and supplied directly to a fuel cell, if the supply of high-pressure hydrogen is stopped for some reason, it will not be possible to supply low-pressure hydrogen to the fuel cell.

[0006] The object of the present application is to provide a configuration that can reduce the pressure of high-pressure hydrogen and supply it directly to a fuel cell, and that allows the supply of low-pressure hydrogen to the fuel cell to continue even if the direct supply is stopped for some reason. [Means for solving the problem]

[0007] The hydrogen supply system according to the first aspect comprises a pressure reducing valve which reduces the pressure of high-pressure hydrogen supplied thereto, a pipe member having a main flow path formed therein for directly supplying the low-pressure hydrogen reduced in pressure by the pressure reducing valve to a fuel cell, a branch pipe member having a branch flow path which branches off from a portion of the main flow path and supplies low-pressure hydrogen to a hydrogen storage unit, a junction pipe member having a junction flow path which joins the hydrogen storage unit to a portion of the main flow path, one three-way valve provided at the branch point of the branch flow paths, another three-way valve provided at the junction point of the junction flow paths, and a control unit which controls the opening and closing of the one three-way valve and the opening and closing of the other three-way valve.

[0008] According to the configuration of the first aspect, high-pressure hydrogen is reduced in pressure by the pressure reducing valve, and the reduced-pressure low-pressure hydrogen flows through the main flow path and is supplied to the fuel cell.

[0009] Meanwhile, the control unit controls the opening and closing of one three-way valve and the opening and closing of the other three-way valve, so that low-pressure hydrogen flows through the branch flow path and is supplied to the hydrogen storage unit, which stores the supplied low-pressure hydrogen.Furthermore, the control unit controls the opening and closing of one three-way valve and the opening and closing of the other three-way valve, so that the low-pressure hydrogen stored in the hydrogen storage unit flows through the confluence flow path and is supplied to the fuel cell.

[0010] As a result, in a configuration in which high-pressure hydrogen can be reduced in pressure and directly supplied to a fuel cell, even if the direct supply is stopped for some reason, the supply of low-pressure hydrogen to the fuel cell can be continued.

[0011] The hydrogen supply system according to the second aspect is characterized in that, in the hydrogen supply system according to the first aspect, a heat exchanger is provided downstream of the pressure reducing valve in the hydrogen flow direction and upstream of the branch point, which acquires heat generated by reducing the pressure of high-pressure hydrogen; the hydrogen storage unit includes a hydrogen storage alloy; and the control unit heats the hydrogen storage alloy, whose temperature has been reduced by releasing low-pressure hydrogen, using the heat acquired by the heat exchanger.

[0012] According to the second aspect, the control unit heats the hydrogen storage alloy, whose temperature has been lowered by releasing low-pressure hydrogen, using the heat acquired by the heat exchanger. In this way, the heat generated by reducing the pressure of the high-pressure hydrogen can be effectively utilized.

[0013] The hydrogen supply system according to the third aspect is the hydrogen supply system according to the first or second aspect, characterized in that the hydrogen storage unit comprises a low-pressure hydrogen tank and a hydrogen storage alloy, and the downstream portion of the branch flow path in the hydrogen flow direction is formed with a first flow path through which low-pressure hydrogen is supplied to the low-pressure hydrogen tank and a second flow path through which low-pressure hydrogen is supplied to the hydrogen storage alloy, and the upstream portion of the converging flow path in the hydrogen flow direction is formed with a third flow path through which low-pressure hydrogen flows from the low-pressure hydrogen tank and a fourth flow path through which low-pressure hydrogen flows from the hydrogen storage alloy.

[0014] In the configuration according to the third aspect, low-pressure hydrogen flows through a first flow path of the branch flow path and is supplied to a low-pressure hydrogen tank, which stores the supplied low-pressure hydrogen.Furthermore, the low-pressure hydrogen flows through a second flow path of the branch flow path and is supplied to a hydrogen storage alloy, which stores the supplied low-pressure hydrogen.

[0015] Meanwhile, low-pressure hydrogen released from the low-pressure hydrogen tank flows through the third flow path of the confluence flow path and is supplied to the fuel cell, and low-pressure hydrogen released from the hydrogen storage alloy flows through the fourth flow path of the confluence flow path and is supplied to the fuel cell.

[0016] In this way, low-pressure hydrogen can be directly supplied to the low-pressure hydrogen tank and the hydrogen storage alloy, and the low-pressure hydrogen released from the low-pressure hydrogen tank and the low-pressure hydrogen released from the hydrogen storage alloy can be directly supplied to the fuel cell. [Effects of the Invention]

[0017] According to the present disclosure, a configuration can be obtained in which high-pressure hydrogen can be reduced in pressure and supplied directly to a fuel cell, and even if the direct supply is stopped for some reason, the supply of low-pressure hydrogen to the fuel cell can continue. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic configuration diagram illustrating a hydrogen supply system according to an embodiment of the present disclosure. [Figure 2] 1 is a diagram showing a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of hydrogen in which high-pressure hydrogen is reduced in pressure and supplied directly to a fuel cell. [Figure 3] 1 is a diagram showing a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of hydrogen that is decompressed from high-pressure hydrogen and supplied directly to a fuel cell, and the flow of hydrogen that is supplied to a hydrogen storage unit. [Figure 4] 1 is a diagram showing a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of hydrogen in which high-pressure hydrogen is reduced in pressure and supplied directly to a fuel cell, and the flow of hydrogen supplied from a hydrogen storage unit to a fuel cell. [Figure 5] 1 is a diagram showing the flow of hydrogen supplied from a hydrogen storage unit to a fuel cell in a hydrogen supply system according to an embodiment of the present disclosure when the direct supply of high-pressure hydrogen is stopped for some reason. [Figure 6] 1 is a schematic diagram illustrating a heat utilization unit provided in a hydrogen supply system according to an embodiment of the present disclosure. [Figure 7] 4 is a diagram showing the flow of a heat exchange medium in a heat utilization unit provided in a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of the heat exchange medium when heating a hydrogen storage alloy. [Figure 8]4 is a diagram showing the flow of a heat exchange medium in a heat utilization unit provided in a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of the heat exchange medium when cooling a hydrogen storage alloy. [Figure 9] 1 is a diagram showing the flow of a heat exchange medium in a heat utilization unit provided in a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of the heat exchange medium when low-pressure hydrogen is released from a hydrogen storage alloy. [Figure 10] 1 is a diagram showing the flow of a heat exchange medium in a heat utilization unit provided in a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of the heat exchange medium when low-pressure hydrogen is absorbed into a hydrogen storage alloy. [Figure 11] 1 is a diagram showing the flow of a heat exchange medium in a heat utilization section provided in a hydrogen supply system according to an embodiment of the present disclosure, illustrating the flow of the heat exchange medium when cooling low-pressure hydrogen flowing through a main flow path. [Figure 12] 2 is a block diagram showing a control system of a control unit provided in a hydrogen supply system according to an embodiment of the present disclosure. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0019] An example of a hydrogen supply system according to an embodiment of the present disclosure will be described with reference to FIGS.

[0020] (Overall composition) 1, the hydrogen supply system 100 includes a pressure reducing valve 12 that reduces the pressure of high-pressure hydrogen supplied from a hydrogen station 102, and a pipe member 20 that has a main flow path 14 formed therein for directly supplying the low-pressure hydrogen reduced in pressure by the pressure reducing valve 12 to a fuel cell 110. The hydrogen supply system 100 also includes a branch pipe member 30 that has a branch flow path 24 that branches off from a portion of the main flow path 14 and supplies low-pressure hydrogen to a hydrogen storage unit 60, and a junction pipe member 50 that has a junction flow path 44 that joins the hydrogen storage unit 60 and the main flow path 14. The hydrogen supply system 100 also includes a heat utilization unit 80 that utilizes heat generated by the Joule-Thomson effect, i.e., heat generated by reducing the pressure of high-pressure hydrogen, and a control unit 68 (see FIG. 12) that controls each unit.

[0021] In this embodiment, the fuel cell 110 is used, for example, to supply power to a building, that is, the hydrogen supply system 100 according to this embodiment is a system used for operating a building.

[0022] [Pipe member 20] As shown in Fig. 1, the pipe member 20 in which the main flow path 14 is formed extends from the pressure reducing valve 12 to the fuel cell 110. Furthermore, a three-way valve 16 is provided at the branch point of the pipe member 20 where the branch flow paths 24 branch off. Furthermore, a three-way valve 18 is provided at the junction point of the pipe member 20 where the junction flow path 44 joins. The three-way valves 16 and 18 are arranged in this order from upstream to downstream in the hydrogen flow direction. The three-way valve 16 is an example of one three-way valve, and the three-way valve 18 is an example of another three-way valve.

[0023] [Hydrogen storage section 60, branch pipe member 30, junction pipe member 50] The hydrogen storage unit 60 has the function of temporarily storing low-pressure hydrogen, and as shown in Fig. 1, includes a low-pressure hydrogen tank 62 and a hydrogen storage alloy 64. Furthermore, the hydrogen storage unit 60 includes a detection unit 64a (see Fig. 12) that detects the temperature of the hydrogen storage alloy 64.

[0024] Furthermore, the branch pipe member 30, which has the branch flow path 24 branching off from the main flow path 14 via the three-way valve 16, branches off at a downstream portion in the hydrogen flow direction. Specifically, it branches off into a pipe member 34, which has a first flow path 32 through which low-pressure hydrogen flows to be supplied to the low-pressure hydrogen tank 62, and a pipe member 38, which has a second flow path 36 through which low-pressure hydrogen flows to be supplied to the hydrogen storage alloy 64.

[0025] An on-off valve 72 for opening and closing the first flow path 32 is provided midway through the pipe member 34, and an on-off valve 74 for opening and closing the second flow path 36 is provided midway through the pipe member 38.

[0026] Furthermore, the junction pipe member 50, which forms the junction flow path 44 that joins the main flow path 14 via the three-way valve 18, branches off at an upstream portion in the hydrogen flow direction. Specifically, it branches off into a pipe member 54, which forms a third flow path 52 through which low-pressure hydrogen from the low-pressure hydrogen tank 62 flows, and a pipe member 58, which forms a fourth flow path 56 through which low-pressure hydrogen from the hydrogen storage alloy 64 flows.

[0027] An on-off valve 76 for opening and closing the third flow path 52 is provided midway through the pipe member 54, and an on-off valve 78 for opening and closing the fourth flow path 56 is provided midway through the pipe member 58.

[0028] [Heat utilization section 80] As shown in Figures 1 and 6, the heat utilization section 80 is attached to the portion of the pipe member 20 between the pressure reducing valve 12 and the three-way valve 16, and is equipped with a heat exchanger 82 that acquires the heat generated by reducing the pressure of the high-pressure hydrogen, and a cold / hot water chiller 84 (hereinafter referred to as "chiller 84").

[0029] Furthermore, the heat utilization unit 80 is provided with a flow path through which the heat exchange medium flows. Specifically, the heat utilization unit 80 is provided with a circulation pipe member 90 in which a circulation flow path 88 is formed, through which the heat exchange medium flows between the chiller 84 and the hydrogen storage alloy 64. This circulation flow path 88 is provided with a circulation flow path 88a leading from the chiller 84 to the hydrogen storage alloy 64, and a circulation flow path 88b leading from the hydrogen storage alloy 64 to the chiller 84.

[0030] Furthermore, the heat utilization section 80 includes an exchange pipe member 94 in which an exchange flow path 92 is formed, which branches off from the middle of the circulation flow path 88a and heads toward the heat exchanger 82, and which joins the middle of the circulation flow path 88b from the heat exchanger 82. The exchange flow path 92 includes an exchange flow path 92a that branches off from the middle of the circulation flow path 88a toward the heat exchanger 82, and an exchange flow path 92b that heads from the heat exchanger 82 toward the circulation flow path 88b.

[0031] A three-way valve 96 is provided at a branch point located midway along the circulation flow path 88a, and a three-way valve 98 is provided at a junction located midway along the circulation flow path 88b. Furthermore, a pump 70 is provided in the circulation pipe member 90 between the three-way valve 98 and the chiller 84. Furthermore, a pump 71 is provided in the exchange pipe member 94 between the three-way valve 96 and the heat exchanger 82.

[0032] [Control unit 68] The control unit 68 controls each unit as shown in Fig. 12. The control of each unit by the control unit 68 will be explained together with the operation described later.

[0033] (action) Next, we will explain the operation of the hydrogen supply system 100. Specifically, first, we will explain examples of the flow of hydrogen in different cases, and then we will explain examples of the flow of the heat exchange medium using the heat utilization unit 80 in different cases.

[0034] [About the flow of hydrogen] -First case distinction- When the low-pressure hydrogen tank 62 is full and hydrogen has been sufficiently absorbed by the hydrogen storage alloy 64, the control unit 68 controls the three-way valve 16 and the three-way valve 18 as shown in Fig. 2. Specifically, the control unit 68 closes the flow of low-pressure hydrogen from the main flow path 14 to the branch flow path 24, and closes the flow of low-pressure hydrogen from the junction flow path 44 to the main flow path 14.

[0035] As a result, the high-pressure hydrogen supplied from the hydrogen station 102 is reduced in pressure by the pressure reducing valve 12. Furthermore, the low-pressure hydrogen reduced in pressure by the pressure reducing valve 12 flows through the main flow path 14 and is supplied directly to the fuel cell 110. The fuel cell 110 generates electricity when supplied with low-pressure hydrogen, and the generated electricity is supplied to the building.

[0036] -Second case distinction- Furthermore, when the low-pressure hydrogen tank 62 is not full, there is room for hydrogen storage by the hydrogen storage alloy 64, and the amount of electricity used by the fuel cell 110 is not large, the control unit 68 controls each part as shown in FIG. 3.

[0037] Specifically, the control unit 68 controls the three-way valves 16 and 18 to open the flow of low-pressure hydrogen from the main flow path 14 to the branch flow path 24 and to block the flow of low-pressure hydrogen from the junction flow path 44 to the main flow path 14. Furthermore, the control unit 68 controls the on-off valves 72 and 74 to open the first flow path 32 and open the second flow path 36. Furthermore, the control unit 68 controls the on-off valves 76 and 78 to close the third flow path 52 and close the fourth flow path 56.

[0038] As a result, the high-pressure hydrogen supplied from the hydrogen station 102 is reduced in pressure by the pressure reducing valve 12. Furthermore, the low-pressure hydrogen reduced in pressure by the pressure reducing valve 12 flows through the main flow path 14 and is supplied to the fuel cell 110. The fuel cell 110 generates electricity by being supplied with low-pressure hydrogen, and the generated electricity is supplied to the building.

[0039] Furthermore, the low-pressure hydrogen that has flowed into the branch flow path 24 via the three-way valve 16 flows through the first flow path 32 and is supplied to the low-pressure hydrogen tank 62. The low-pressure hydrogen supplied to the low-pressure hydrogen tank 62 is then stored in the low-pressure hydrogen tank 62.

[0040] Furthermore, the low-pressure hydrogen that has flowed into the branch flow path 24 via the three-way valve 16 flows through the second flow path 36 and is supplied to the hydrogen storage alloy 64. The low-pressure hydrogen that has been supplied to the hydrogen storage alloy 64 is then absorbed by the hydrogen storage alloy 64.

[0041] -Third case- Furthermore, when low-pressure hydrogen is stored in the low-pressure hydrogen tank 62 and absorbed by the hydrogen storage alloy 64, and when a large amount of electricity is used by the fuel cell 110, the control unit 68 controls each part as shown in FIG. 4.

[0042] Specifically, the control unit 68 controls the three-way valves 16 and 18 to close the flow of low-pressure hydrogen from the main flow path 14 to the branch flow path 24 and to open the flow of low-pressure hydrogen from the junction flow path 44 to the main flow path 14. Furthermore, the control unit 68 controls the on-off valves 72 and 74 to close the first flow path 32 and close the second flow path 36. Furthermore, the control unit 68 controls the on-off valves 76 and 78 to open the third flow path 52 and open the fourth flow path 56.

[0043] As a result, high-pressure hydrogen supplied from the hydrogen station 102 is reduced in pressure by the pressure reducing valve 12. Furthermore, the low-pressure hydrogen reduced in pressure by the pressure reducing valve 12 flows through the main flow path 14 and is supplied to the fuel cell 110.

[0044] Furthermore, the low-pressure hydrogen stored in the low-pressure hydrogen tank 62 is released into the third flow path 52, flows through the confluence flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110.

[0045] Furthermore, the low-pressure hydrogen stored in the hydrogen storage alloy 64 is released into the fourth flow path 56, flows through the confluence flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110. The fuel cell 110 generates electricity when supplied with low-pressure hydrogen, and the generated electricity is supplied to the building.

[0046] -Fourth case- Furthermore, if the direct supply of high-pressure hydrogen from the hydrogen station 102 is stopped for some reason, the control unit 68 controls each unit as shown in FIG.

[0047] Specifically, the control unit 68 controls the three-way valve 16 to close the flow of low-pressure hydrogen, and controls the three-way valve 18 to open the flow of low-pressure hydrogen from the junction flow path 44 to the portion of the main flow path 14 on the fuel cell 110 side. Furthermore, the control unit 68 controls the on-off valve 72 and the on-off valve 74 to close the first flow path 32 and close the second flow path 36. Furthermore, the control unit 68 controls the on-off valve 76 and the on-off valve 78 to open the third flow path 52 and open the fourth flow path 56.

[0048] As a result, the low-pressure hydrogen stored in the low-pressure hydrogen tank 62 is released into the third flow path 52, flows through the merging flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110.

[0049] Furthermore, the low-pressure hydrogen stored in the hydrogen storage alloy 64 is released into the fourth flow path 56, flows through the confluence flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110. The fuel cell 110 generates electricity when supplied with low-pressure hydrogen, and the generated electricity is supplied to the building.

[0050] [Flow of heat exchange medium] -First case distinction- When the temperature of the hydrogen absorbing alloy 64 detected by the detector 64 a is lower than the predetermined temperature range, the controller 68 controls the three-way valve 96 , the three-way valve 98 and the pump 71 .

[0051] 7, the control unit 68 controls the three-way valve 98 to allow the heat exchange medium to flow from the exchange flow path 92b to the portion of the circulation flow path 88b on the hydrogen storage alloy 64 side, and controls the three-way valve 96 to allow the heat exchange medium to flow from the portion of the circulation flow path 88a on the hydrogen storage alloy 64 side to the exchange flow path 92a. Furthermore, the control unit 68 operates the pump 71.

[0052] As a result, the heat exchange medium warmed by the heat acquired by the heat exchanger 82 flows through each flow path (see arrows in the figure). Then, the heat acquired by the heat exchanger 82 is transferred to the hydrogen storage alloy 64 via the heat exchange medium, heating the hydrogen storage alloy 64 and bringing the temperature of the hydrogen storage alloy 64 within a predetermined temperature range.

[0053] -Second case distinction- When the temperature of the hydrogen absorbing alloy 64 detected by the detector 64 a is higher than a predetermined temperature range, the controller 68 controls the three-way valve 96 , the three-way valve 98 and the pump 70 .

[0054] 8, the control unit 68 controls the three-way valve 96 to allow the heat exchange medium to flow from the circulation flow path 88a on the chiller 84 side to the circulation flow path 88a on the hydrogen storage alloy 64 side, and controls the three-way valve 98 to allow the heat exchange medium to flow from the circulation flow path 88b on the hydrogen storage alloy 64 side to the circulation flow path 88b on the chiller 84 side. Furthermore, the control unit 68 operates the pump 70.

[0055] As a result, the cooled heat exchange medium generated by the chiller 84 flows through each flow path (see the arrows in the figure), cooling the hydrogen storage alloy 64. Then, the temperature of the hydrogen storage alloy 64 becomes within a predetermined temperature range.

[0056] -Third case- 9, when low-pressure hydrogen is to be released from the hydrogen storage alloy 64, the on-off valve 74 is closed and the on-off valve 78 is opened. This reduces the pressure applied to the hydrogen storage alloy 64, causing the low-pressure hydrogen to be released from the hydrogen storage alloy 64. Furthermore, as the low-pressure hydrogen is released from the hydrogen storage alloy 64, the hydrogen storage alloy 64 absorbs heat, causing the temperature of the hydrogen storage alloy 64 to drop. Therefore, the control unit 68 controls the three-way valve 96, the three-way valve 98, and the pump 71.

[0057] Specifically, the control unit 68 controls the three-way valve 98 to allow the heat exchange medium to flow from the exchange flow path 92b to the portion of the circulation flow path 88b on the hydrogen storage alloy 64 side, and controls the three-way valve 96 to allow the heat exchange medium to flow from the portion of the circulation flow path 88a on the hydrogen storage alloy 64 side to the exchange flow path 92a. Furthermore, the control unit 68 operates the pump 71.

[0058] As a result, the heat exchange medium warmed by the heat acquired by the heat exchanger 82 flows through each flow path (see the arrows in the figure). Then, the heat acquired by the heat exchanger 82 is transferred to the hydrogen storage alloy 64 via the heat exchange medium, heating the hydrogen storage alloy 64, whose temperature has dropped due to the release of low-pressure hydrogen, and the temperature of the hydrogen storage alloy 64 falls within a predetermined temperature range.

[0059] -Fourth case- When low-pressure hydrogen is stored in the hydrogen storage alloy 64, the on-off valve 74 is opened and the on-off valve 78 is closed, as shown in Figure 10. This increases the pressure applied to the hydrogen storage alloy 64, causing low-pressure hydrogen to be absorbed in the hydrogen storage alloy 64. Furthermore, as low-pressure hydrogen is absorbed in the hydrogen storage alloy 64, the hydrogen storage alloy 64 generates heat, causing the temperature of the hydrogen storage alloy 64 to rise. Therefore, the control unit 68 controls the three-way valve 96, the three-way valve 98, and the pump 70.

[0060] Specifically, the control unit 68 controls the three-way valve 96 to allow the heat exchange medium to flow from the circulation flow path 88a on the chiller 84 side to the circulation flow path 88a on the hydrogen storage alloy 64 side, and controls the three-way valve 98 to allow the heat exchange medium to flow from the circulation flow path 88b on the hydrogen storage alloy 64 side to the circulation flow path 88b on the chiller 84 side. Furthermore, the control unit 68 operates the pump 70.

[0061] As a result, the cooled heat exchange medium generated by the chiller 84 flows through each flow path (see the arrows in the figure), cooling the hydrogen storage alloy 64. Then, the temperature of the hydrogen storage alloy 64, which has increased due to the absorption of low-pressure hydrogen, falls within a predetermined temperature range.

[0062] -Fifth Case- When the temperature of the hydrogen absorbing alloy 64 detected by the detector 64 a is within a predetermined temperature range, the controller 68 controls the three-way valve 96 , the three-way valve 98 and the pump 70 .

[0063] 11, the control unit 68 controls the three-way valve 96 to allow the heat exchange medium to flow from the portion of the circulation flow path 88a on the chiller 84 side to the exchange flow path 92a, and controls the three-way valve 98 to allow the heat exchange medium to flow from the exchange flow path 92b to the portion of the circulation flow path 88b on the chiller 84 side. Furthermore, the control unit 68 operates the pump 70.

[0064] As a result, the cooled heat exchange medium produced by the chiller 84 flows through each flow path (see arrows in the figure), and the low-pressure hydrogen, which has become hot due to the heat generated by decompressing the high-pressure hydrogen, is cooled by the heat exchanger 82.

[0065] (summary) As described above, in the hydrogen supply system 100, if the supply of high-pressure hydrogen from the hydrogen station 102 is stopped for some reason, as shown in FIG. 5 , the low-pressure hydrogen stored in the low-pressure hydrogen tank 62 is released into the third flow path 52, flows through the merging flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110. Furthermore, the low-pressure hydrogen stored in the hydrogen storage alloy 64 is released into the fourth flow path 56, flows through the merging flow path 44, and merges with the main flow path 14. The low-pressure hydrogen that has merged with the main flow path 14 then flows through the main flow path 14 and is supplied to the fuel cell 110.

[0066] In this way, even if the direct supply of high-pressure hydrogen is stopped for some reason, the supply of low-pressure hydrogen to the fuel cell 110 can continue.

[0067] Furthermore, in the hydrogen supply system 100, when low-pressure hydrogen is released from the hydrogen storage alloy 64, the hydrogen storage alloy 64 absorbs heat and the temperature of the hydrogen storage alloy 64 drops. Therefore, the control unit 68 controls each unit to heat the hydrogen storage alloy 64 using the heat generated by depressurizing the high-pressure hydrogen, as shown in Fig. 9. In this way, the heat generated by depressurizing the high-pressure hydrogen can be effectively utilized.

[0068] In the hydrogen supply system 100, the downstream portion of the branch flow path 24 in the hydrogen flow direction branches into a pipe member 34 having a first flow path 32 formed therein through which low-pressure hydrogen flows to be supplied to the low-pressure hydrogen tank 62, and a pipe member 38 having a second flow path 36 formed therein through which low-pressure hydrogen flows to be supplied to the hydrogen storage alloy 64. This allows low-pressure hydrogen to be directly supplied to the low-pressure hydrogen tank 62 and the hydrogen storage alloy 64.

[0069] In the hydrogen supply system 100, the upstream portion of the junction flow path 44 in the hydrogen flow direction branches into a pipe member 54 having a third flow path 52 formed therein into which low-pressure hydrogen flows from the low-pressure hydrogen tank 62, and a pipe member 58 having a fourth flow path 56 formed therein into which low-pressure hydrogen flows from the hydrogen storage alloy 64. This allows the low-pressure hydrogen released from the low-pressure hydrogen tank 62 and the low-pressure hydrogen released from the hydrogen storage alloy 64 to be directly supplied to the fuel cell 110.

[0070] Although the present disclosure has been described in detail with respect to specific embodiments, it will be apparent to those skilled in the art that the present disclosure is not limited to such embodiments and that various other embodiments are possible within the scope of the present disclosure. Although not specifically described in the above embodiment, the fuel cell 110 may be heated by heat generated by decompressing the high-pressure hydrogen, thereby preventing the temperature of the fuel cell 110 from decreasing.

[0071] Although not specifically described in the above embodiment, the heat exchange medium may be heated by the chiller 84, and the hydrogen storage alloy may be heated using the heated heat exchange medium. [Explanation of symbols]

[0072] 12 Pressure reducing valve 14 Main channel 16 Three-way valve (an example of a three-way valve) 18 Three-way valve (an example of another three-way valve) 20 Pipe members 24 Branching Channel 30 Branch pipe member 32 First Channel 36 Second flow path 44 Confluence 50 Confluence pipe member 52 Third flow path 56 Fourth channel 60 Hydrogen storage unit 62 Low-pressure hydrogen tank 64 Hydrogen storage alloy 68 Control Unit 82 Heat exchanger 100 Hydrogen Supply System 110 Fuel Cell

Claims

1. a pressure reducing valve that receives high-pressure hydrogen and reduces the pressure of the high-pressure hydrogen; a pipe member having a main flow path formed therein for directly supplying the low-pressure hydrogen reduced in pressure by the pressure reducing valve to the fuel cell; a branch pipe member having a branch flow path branching from a middle portion of the main flow path to supply low-pressure hydrogen to a hydrogen storage section; a junction pipe member having a junction flow path formed therein that joins the hydrogen storage section to a midpoint of the main flow path; a three-way valve provided at a branch point of the branch flow path; Another three-way valve provided at the junction of the junction flow paths; a control unit that controls opening and closing of the one three-way valve and opening and closing of the other three-way valve; A hydrogen supply system comprising:

2. a heat exchanger for acquiring heat generated by reducing the pressure of the high-pressure hydrogen is provided downstream of the pressure reducing valve and upstream of the branch point in the hydrogen flow direction; the hydrogen storage unit includes a hydrogen storage alloy, the control unit heats the hydrogen storage alloy, the temperature of which has been reduced by releasing low-pressure hydrogen, with the heat obtained by the heat exchanger. The hydrogen supply system according to claim 1 .

3. the hydrogen storage unit includes a low-pressure hydrogen tank and a hydrogen storage alloy; a first flow path for supplying low-pressure hydrogen to the low-pressure hydrogen tank and a second flow path for supplying low-pressure hydrogen to the hydrogen storage alloy are formed in a downstream portion of the branch flow path in the hydrogen flow direction; a third flow path through which low-pressure hydrogen from the low-pressure hydrogen tank flows and a fourth flow path through which low-pressure hydrogen from the hydrogen storage alloy flows are formed in an upstream portion of the junction flow path in the hydrogen flow direction; The hydrogen supply system according to claim 1 or 2.

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