Fuel gas storage system

Abstract

To provide a fuel gas storage system having a plurality of tanks.SOLUTION: The fuel gas storage system includes a first tank including a first supply valve and a first communication valve. The fuel gas storage system includes a second tank including a second supply valve and a second communication valve. The fuel gas storage system includes a supply pipe connecting the first supply valve and the second supply valve to an external device. The fuel gas storage system includes a communication pipe that connects the first communication valve and the second communication valve to each other. The fuel gas storage system includes a controller configured to control an open / closed state of each of the first supply valve, the second supply valve, the first connecting valve, and the second connecting valve. The controller is configured or programmed to execute a specific control to close the first supply valve and open the first connecting valve, the second connecting valve, and the second supply valve.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a fuel gas storage system. [Background technology]

[0002] Patent Document 1 discloses a fuel gas storage device equipped with a plurality of tanks. Each of the plurality of tanks is equipped with a valve. Each of the plurality of tanks is connected to a supply pipe via the valve. The supply pipe is connected to an external device to which the fuel gas is to be supplied. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-97795 Summary of the Invention [Problem to be solved by the invention]

[0004] There are cases where it is desirable to not open or close a tank valve. For example, if the valve is broken or if the valve is being opened and closed frequently, fuel gas cannot be supplied from the tank with a valve that is not opened or closed. [Means for solving the problem]

[0005] The fuel gas storage system disclosed in this specification is configured to be able to store fuel gas and includes a first tank having a first supply valve and a first communication valve. The fuel gas storage system is configured to be able to store fuel gas and includes a second tank having a second supply valve and a second communication valve. The fuel gas storage system includes a supply pipe connecting the first supply valve and the second supply valve to an external device. The fuel gas storage system includes a communication pipe connecting the first communication valve and the second communication valve to each other. The fuel gas storage system includes a control unit configured to be able to control the open / closed states of the first supply valve, the second supply valve, the first communication valve, and the second communication valve. The control unit is configured to be able to execute specific control to close the first supply valve and open the first communication valve, the second communication valve, and the second supply valve.

[0006] According to the above configuration, when the first supply valve is not operated, the fuel gas in the first tank can be supplied to an external device using a route that passes through the first communication valve, communication pipe, second communication valve, second tank, second supply valve, and supply pipe. Even when the first supply valve is not operated, the fuel gas can be supplied from the first tank. This allows the fuel gas stored in the first tank to be used effectively. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing a schematic configuration of a fuel cell system 1. FIG. [Figure 2] 10 is a flowchart illustrating the operation of the fuel gas storage system 2. [Figure 3] 3 is a diagram illustrating a specific example of the operation of the fuel gas storage system 2. FIG. [Figure 4] 10 is a flowchart illustrating the operation of the fuel gas storage system 2 in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following are additional features of the drive device disclosed in this specification:

[0009] The control unit may be configured to be able to execute specific control when a failure in the first supply valve is detected.

[0010] According to the above configuration, even if the first supply valve is out of order, it is possible to supply fuel gas from the first tank to the external device.

[0011] The control unit may be further configured to detect the number of times the first supply valve is operated. The control unit may be configured to execute specific control when the number of times the first supply valve is operated exceeds a predetermined number.

[0012] According to the above configuration, it is possible to supply fuel gas from the first tank to the external device while suppressing the number of times the first supply valve is operated.

[0013] The control unit may be configured to be able to execute the specific control when the pressure in the second tank is lower than the pressure in the first tank.

[0014] According to the above configuration, the fuel gas in the first tank can be appropriately moved to the second tank by the pressure difference.

[0015] A first supply valve may be disposed at one end of the first tank, and a first communication valve may be disposed at the other end of the first tank. A second supply valve may be disposed at one end of the second tank, and a second communication valve may be disposed at the other end of the second tank. [Example]

[0016] (Schematic configuration of fuel cell system 1 and fuel gas storage system 2) 1 shows a schematic configuration of a fuel cell system 1 of this embodiment. The fuel cell system 1 includes a fuel gas storage system 2 and a fuel cell 3. The fuel cell 3 is connected to the fuel gas storage system 2 via a supply pipe 41. Hydrogen gas is supplied from the fuel gas storage system 2 to the fuel cell 3. The configuration of the fuel cell 3 is well known, so a detailed description will be omitted.

[0017] The fuel gas storage system 2 mainly includes a first tank 11, a second tank 12, a third tank 13, and a control unit 40. The first tank 11, the second tank 12, and the third tank 13 are configured to be able to store fuel gas. The stored fuel gas may be of various types. In this embodiment, the fuel gas is hydrogen gas.

[0018] The first tank 11 includes a first supply valve 21 and a first communication valve 31. The first supply valve 21 is disposed at an end 11e1 on one side of the first tank 11. The first communication valve 31 is disposed at an end 11e2 on the other side of the first tank 11. Similarly, the second tank 12 includes a second supply valve 22 and a second communication valve 32. The second supply valve 22 is disposed at an end 12e1, and the second communication valve 32 is disposed at an end 12e2. Similarly, the third tank 13 includes a third supply valve 23 and a third communication valve 33. The third supply valve 23 is disposed at an end 13e1, and the third communication valve 33 is disposed at an end 13e2.

[0019] The supply pipe 41 connects the first supply valve 21, the second supply valve 22, and the third supply valve 23 to the fuel cell 3, which is an external device. The communication pipe 42 connects the first communication valve 31, the second communication valve 32, and the third communication valve 33 to one another. That is, the communication pipe 42 connects the first tank 11, the second tank 12, and the third tank 13 to one another in common.

[0020] The control unit 40 is communicatively connected to the first supply valve 21 to the third supply valve 23 and the first communication valve 31 to the third communication valve 33. In FIG. 1, the communication paths are indicated by dotted lines. The control unit 40 is capable of controlling the open / closed state of each of these six valves. The control unit 40 is also configured to count the number of times each of these six valves is opened and closed, and to detect whether or not a malfunction has occurred. The control unit 40 is also configured to detect the internal pressure and remaining gas amount of each of the first tank 11 to the third tank 13.

[0021] The fuel gas storage system 2 may be provided with various devices such as a high-pressure regulator for keeping the discharge pressure constant, and a relief valve for releasing excess pressure in the tank.

[0022] (Fuel gas storage system 2 operation details) The operation of the fuel gas storage system 2 will be described using the flowchart in Figure 2. In the initial state before the start of the flowchart, all valves are closed. In step S10, the control unit 40 determines whether or not to start supplying hydrogen gas to the fuel cell 3. If the determination is negative (S10: NO), the control unit 40 waits, and if the determination is positive (S10: YES), the control unit 40 proceeds to step S20.

[0023] In step S20, the control unit 40 determines whether a malfunction has occurred in at least one of the first supply valve 21 to the third supply valve 23. Various types of malfunctions may occur. For example, a closing malfunction, a malfunction resulting in an insufficient opening, or a malfunction resulting in a long opening / closing time may be cited. If no malfunction has occurred (S20: NO), the process proceeds to step S40; if a malfunction has occurred (S20: YES), the process proceeds to step S30.

[0024] In step S30, the control unit 40 determines whether hydrogen gas remains in the tank equipped with a normal supply valve. If there is hydrogen gas remaining (S30: YES), the process proceeds to step S40. In step S40, the control unit 40 opens the normal supply valve. This allows hydrogen gas to be supplied to the fuel cell 3 from the tank equipped with a normal supply valve. The process then proceeds to step S70.

[0025] If there are multiple tanks with normal supply valves, one of the tanks can be selected and the supply valve of the selected tank can be opened. Various methods for selecting the tank are possible. For example, the tank with the highest internal pressure may be selected, the tank with the lowest internal pressure may be selected, or the tank whose supply valve has been opened and closed the least number of times may be selected.

[0026] On the other hand, if it is determined in step S30 that no hydrogen gas remains in the tank equipped with a normal supply valve (S30: NO), the process proceeds to step S50. In step S50, the control unit 40 executes specific control. The specific control is a control for forming a gas path that bypasses the faulty supply valve. The specific control can be executed when a fault is detected in at least one of the first supply valve 21 to the third supply valve 23 (S20: YES).

[0027] In the specific control, the faulty supply valve is maintained in a closed state. In addition, in the specific control, the communication valve of the tank with the faulty supply valve is opened, and the communication valve and supply valve of the tank with a normal supply valve are opened. This allows hydrogen gas in the tank with the faulty supply valve to be supplied to the fuel cell 3 via the tank with the normal supply valve. Then, the process proceeds to step S70.

[0028] If there are multiple tanks with normal supply valves, one of the tanks can be selected and the communication valve and supply valve of the selected tank can be opened. Various methods for selecting the tank are possible. For example, the tank closest to the faulty supply valve can be selected, or the tank whose supply valve has been opened and closed the least number of times can be selected.

[0029] In step S70, the control unit 40 determines whether or not to terminate the supply of hydrogen gas to the fuel cell 3. If a negative determination is made (S70: NO), the process returns to step S20, where the supply of hydrogen gas continues. On the other hand, if a positive determination is made (S70: YES), the process proceeds to step S80. In step S80, the control unit 40 closes all of the first supply valve 21 to the third supply valve 23 and the first communication valve 31 to the third communication valve 33. The process then returns to step S10.

[0030] (Specific operation example of fuel gas storage system 2) A specific example of the operation of the fuel gas storage system 2 will be described using the specific example of Fig. 3. The specific example of Fig. 3 is an example in which the first supply valve 21 is malfunctioning, while the second supply valve 22 and the third supply valve 23 are normal. In this case, in step S20, it is determined that the first supply valve 21 is malfunctioning.

[0031] In step S30, it is determined that hydrogen gas remains in the second tank 12 and the third tank 13, which have normal supply valves. Therefore, in step S40, the second supply valve 22 is opened, thereby supplying hydrogen gas from the second tank 12 to the fuel cell 3 (see gas path G1). Then, when the second tank 12 becomes empty, the third supply valve 23 is opened, thereby supplying hydrogen gas from the third tank 13 to the fuel cell (see gas path G2).

[0032] When both the second tank 12 and the third tank 13 are empty, it is determined that there is no hydrogen gas remaining in the tank with a normal supply valve (S30: NO). Therefore, in S50, specific control is executed. In this operation example, a case will be described in which, of the second tank 12 and the third tank 13 with normal supply valves, the second tank 12 is selected as the target of specific control.

[0033] In the specific control, the faulty first supply valve 21 is maintained in a closed state. Also, the first communication valve 31 of the first tank 11 is opened. Also, the second communication valve 32 and the second supply valve 22 of the second tank 12 are opened. This allows a gas path G3 to be formed from the first tank 11 via the first communication valve 31, the communication pipe 42, the second communication valve 32, the second tank 12, the second supply valve 22, and the supply pipe 41 to the fuel cell 3. Therefore, hydrogen gas in the first tank 11 can be supplied to the fuel cell 3 via the second supply valve 22 of the second tank 12.

[0034] The order in which the multiple valves are opened may vary. For example, the first communication valve 31, the second communication valve 32, and the second supply valve 22 may be opened in that order, or they may all be opened simultaneously.

[0035] The third tank 13 may be selected as the target of specific control. In this case, a gas path G4 can be formed from the first tank 11 to the fuel cell 3 via the first communication valve 31, the communication pipe 42, the third communication valve 33, the third tank 13, the third supply valve 23, and the supply pipe 41.

[0036] (effect) If the first supply valve 21 malfunctions, hydrogen gas cannot be supplied from the first tank 11 to the fuel cell 3 using the first supply valve 21. Therefore, the technology of this embodiment is provided with the first communication valve 31, the third communication valve 33, and the communication pipe 42. The first communication valve 31, the communication pipe 42, and the second communication valve 32 are used to transfer hydrogen gas from the first tank 11 to the second tank 12. Therefore, hydrogen gas can be supplied from the first tank 11 to the fuel cell 3 via the second supply valve 22 of the second tank 12 (see gas path G3). Furthermore, the first communication valve 31, the communication pipe 42, and the third communication valve 33 are used to transfer hydrogen gas from the first tank 11 to the third tank 13. Therefore, hydrogen gas can be supplied from the first tank 11 to the fuel cell 3 via the third supply valve 23 of the third tank 13 (see gas path G4). This makes it possible to effectively utilize the fuel gas stored in the first tank 11.

[0037] If the second supply valve 22 is out of order, a gas path via the first supply valve 21 of the first tank 11 or a gas path via the third supply valve 23 of the third tank 13 can be formed. This makes it possible to supply hydrogen gas from the second tank 12 to the fuel cell 3. If the third supply valve 23 is out of order, a gas path via the first supply valve 21 of the first tank 11 or a gas path via the second supply valve 22 of the second tank 12 can be formed. This makes it possible to supply hydrogen gas from the third tank 13 to the fuel cell 3.

[0038] In the technology of this embodiment, specific control is executed (S50) on the condition that it is determined that no hydrogen gas remains in the tank (second tank 12) with a normal supply valve (S30: NO). This allows specific control to be executed when the pressure in the tank (second tank 12) with a normal supply valve is lower than the pressure in the tank (first tank 11) with a faulty supply valve. Therefore, it is possible to appropriately transfer fuel gas from the tank with the faulty supply valve to the tank with a normal supply valve by using the pressure difference. This makes it possible to effectively utilize the fuel gas stored in the tank with the faulty supply valve. [Example]

[0039] In the second embodiment, the conditions for executing the specific control are different from those in the first embodiment. The operation of the fuel gas storage system 2 in the second embodiment will be described using the flowchart in Fig. 4. Only the differences from the first embodiment will be described below.

[0040] In step S20a, the control unit 40 determines whether an overoperated supply valve has occurred in at least one of the first supply valve 21 to the third supply valve 23. An overoperated supply valve is a valve whose cumulative number of operations exceeds a predetermined number. The predetermined number may be determined in various ways. For example, the predetermined number may be the endurance number determined in the specifications of the first supply valve 21 to the third supply valve 23, or the endurance number minus a margin. Alternatively, the predetermined number may be calculated each time based on the usage environment and operating time of the fuel gas storage system 2. If an overoperated supply valve has not occurred (S20a: NO), the process proceeds to step S40. If an overoperated supply valve has occurred (S20a: YES), the process proceeds to step S30.

[0041] In step S50, the control unit 40 executes specific control. In the specific control, the over-operated supply valve is maintained in a closed state. In the specific control, the communication valve of the tank having the over-operated supply valve is opened, and the communication valve and supply valve of the tank having a normal supply valve are opened. Note that the details of the specific control have been explained in Example 1, so explanation will be omitted here.

[0042] (effect) In a system in which multiple tanks are commonly connected to external devices via supply valves, if each supply valve is driven individually, unevenness in the number of times the supply valves operate among the tanks will occur. As a result, a supply valve that operates more frequently will reach its endurance limit earlier than the other supply valves, becoming an over-operated supply valve. As a result, hydrogen gas cannot be supplied from a tank with an over-operated supply valve. Therefore, the technology of this embodiment makes it possible to supply hydrogen gas from a tank with an over-operated supply valve to the fuel cell 3 via a tank with a normal supply valve. This makes it possible to effectively utilize the fuel gas stored in a tank with an over-operated supply valve.

[0043] In the technology of this embodiment, if an over-operated supply valve occurs, use of the over-operated supply valve is stopped from that point on. Then, hydrogen gas in a tank with an over-operated supply valve can be supplied using a normal supply valve. This makes it possible to correct the imbalance in the number of operations among multiple supply valves. It also makes it possible to extend the overall lifespan of multiple supply valves.

[0044] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings simultaneously achieves multiple objectives, and achieving one of these objectives itself has technical utility.

[0045] (Variation) In step S30, the condition for transitioning to execution of specific control is not limited to "no hydrogen gas remaining in the tank with a normal supply valve." For example, the condition may be "the pressure in the tank with a normal supply valve is lower than the pressure in the tank with a faulty supply valve."

[0046] In this embodiment, the fuel gas storage system 2 is described as having three tanks, but the present invention is not limited to this. The technology of this specification is also applicable to a case where the fuel gas storage system 2 has two tanks or four or more tanks. The technology of this specification is also applicable to a case where two or more supply valves are malfunctioning or over-operating. [Explanation of symbols]

[0047] 1: Fuel cell system 2: Fuel gas storage system 3: Fuel cell 11: First tank 12: Second tank 13: Third tank 21: First supply valve 22: Second supply valve 23: Third supply valve 31: First connecting valve 32: Second connecting valve 33: Third connecting valve 40: Control unit 41: Supply pipe 42: Connecting pipe

Claims

1. a first tank configured to be able to store fuel gas and equipped with a first supply valve and a first communication valve; a second tank configured to be able to store the fuel gas and equipped with a second supply valve and a second communication valve; a supply pipe connecting the first supply valve and the second supply valve to an external device; a communication pipe connecting the first communication valve and the second communication valve to each other; a control unit configured to be able to control the opening and closing states of the first supply valve, the second supply valve, the first communication valve, and the second communication valve; Equipped with the control unit is configured to be able to execute specific control to close the first supply valve and open the first communication valve, the second communication valve, and the second supply valve. Fuel gas storage systems.

2. The fuel gas storage system according to claim 1 , wherein the control unit is configured to be able to execute the specific control when a failure of the first supply valve is detected.

3. the control unit is further configured to detect the number of times the first supply valve is operated; The fuel gas storage system of claim 1, wherein the control unit is configured to execute the specific control when the number of times the first supply valve is operated exceeds a predetermined number of times.

4. A fuel gas storage system described in any one of claims 1 to 3, wherein the control unit is configured to be able to execute the specific control when the pressure in the second tank is lower than the pressure in the first tank.

5. the first supply valve is disposed at one end of the first tank, and the first communication valve is disposed at the other end of the first tank; 2. The fuel gas storage system according to claim 1, wherein the second supply valve is disposed at one end of the second tank, and the second communication valve is disposed at the other end of the second tank.

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