Gas utilization unit

Abstract

To suppress impact pressure applied to a valve of a gas utilization device when a valve of a gas tank is opened in the gas utilization unit in which gas of the gas tank is supplied to the gas utilization device.SOLUTION: A gas utilization unit includes: a gas tank having a first valve; a gas utilization device having a second valve; a gas pipe that connects the first valve and the second valve; a third valve provided in the gas pipe; and a controller. With the second valve closed, the controller alternately executes opening / closing of the first valve and opening / closing of the third valve. This processing gradually increases internal pressure of the gas pipe between the second valve and the third valve. When the internal pressure of the gas pipe between the second valve and the third valve reaches a predetermined threshold value, the controller opens the first valve, the second valve, and the third valve.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a gas-using apparatus including a gas tank and a gas-using device. [Background technology]

[0002] The gas tank is equipped with a valve at the gas outlet. The gas-using device is equipped with a valve at the gas inlet. For ease of explanation, the valve at the gas tank is referred to as the first valve, and the valve at the gas inlet of the gas-using device is referred to as the second valve. The first and second valves are connected by a gas pipe, and when both valves are opened, the gas in the gas tank is supplied to the gas-using device. If the appropriate gas pressure range of the gas-using device is lower than the internal pressure of the gas tank, a pressure reducing valve or a pressure regulating valve is used for the second valve (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 019936 Summary of the Invention [Problem to be solved by the invention]

[0004] When a gas tank is used in various gas-using devices, some of the gas-using devices may have a second valve with low impact pressure resistance. The gas tank is connected to the gas-using device and the first valve is opened. Gas from the gas tank reaches the second valve all at once. Due to the sudden change in pressure, the second valve is momentarily subjected to a pressure higher than the internal pressure of the gas tank. This pressure is called impact pressure or thrust pressure. If the second valve does not have sufficient impact pressure resistance, the second valve may be damaged. This specification provides a technology for suppressing the impact pressure applied to the valve of a gas-using device. [Means for solving the problem]

[0005] The gas-using apparatus disclosed in this specification includes a gas tank having a first valve, a gas-using device having a second valve, a gas pipe connecting the first valve and the second valve, a third valve provided in the gas pipe, and a controller. The controller alternately opens and closes the first valve and the third valve while keeping the second valve closed. This process gradually increases the internal pressure of the gas pipe between the second valve and the third valve. When the internal pressure of the gas pipe between the second valve and the third valve reaches a predetermined threshold pressure, the controller opens the first valve, the second valve, and the third valve. In the gas-using apparatus disclosed in this specification, the pressure applied to the second valve gradually increases. Impact pressure applied to the valve (second valve) of the gas-using device is suppressed.

[0006] Details and further improvements of the technology disclosed in this specification are described in the following "Description of Embodiments of the Invention." [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing the structure of a gas utilization device (FC power generation device) according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] A gas-using device of the embodiment will be described with reference to the drawings. The gas-using device of the embodiment is an FC power generation device 2. Here, "FC" stands for "Fuel Cell." The FC power generation device 2 is also generally called a fuel cell. Figure 1 shows a block diagram of the FC power generation device 2.

[0009] The FC power generation system 2 includes a hydrogen storage module 10, an FC unit 20, and a controller 30. The controller 30 may be included in either the hydrogen storage module 10 or the FC unit 20. The FC power generation system 2 supplies hydrogen gas from hydrogen tanks 11a and 11b of the hydrogen storage module 10 to the FC main body 21 of the FC unit 20 to generate electricity.

[0010] The hydrogen storage module 10 includes two hydrogen tanks 11a and 11b that store hydrogen gas. The hydrogen tank 11a includes a tank valve 14a, and the hydrogen tank 11b includes a tank valve 14b. The tank valve 14a (14b) is provided at the gas outlet of the hydrogen tank 11a (11b). When the tank valve 14a (14b) is opened, hydrogen gas is discharged from the hydrogen tank 11a (11b).

[0011] The FC unit 20 includes an FC main body 21 and an inlet valve 22. The inlet valve 22 and the FC main body 21 are connected by a gas pipe. The inlet valve 22 is provided at the gas inlet of the FC unit 20 (gas-using device).

[0012] The two tank valves 14a, 14b (two hydrogen tanks 11a and 11b) and the inlet valve 22 (FC main body 21) are connected by a gas pipe 12. An electromagnetic valve 15 is provided midway along the gas pipe 12. For ease of explanation, the section of the gas pipe 12 between the electromagnetic valve 15 and the tank valves 14a, 14b will be referred to as the first sub-pipe 12a, and the section of the gas pipe 12 between the electromagnetic valve 15 and the inlet valve 22 will be referred to as the second sub-pipe 12b.

[0013] A fluid coupler 40 is provided midway along the gas pipe 12. In the example of FIG. 1, the fluid coupler 40 is provided midway along the second sub-pipe 12b. The gas pipe 12 can be separated by the fluid coupler 40. In other words, the hydrogen storage module 10 and the FC unit 20 can be separated. The hydrogen storage module 10 can also be connected to a gas-utilizing device other than the FC unit 20.

[0014] One end of the first sub-pipe 12a is connected to the tank valves 14a and 14b, and the other end of the first sub-pipe 12a is connected to the inlet 15a of the electromagnetic valve 15. One end of the second sub-pipe 12b is connected to the outlet 15b of the electromagnetic valve 15, and the other end of the second sub-pipe 12b is connected to the inlet valve 22.

[0015] The expressions "inlet 15a" and "outlet 15b" of the solenoid valve 15 are convenient names to distinguish between the two ports of the valve. For ease of explanation, the internal pressure of the first sub-pipe 12a will be referred to as the upstream pipe pressure, and the internal pressure of the second sub-pipe 12b will be referred to as the downstream pipe pressure. The upstream pipe pressure corresponds to the pressure on the inlet 15a side of the solenoid valve 15, and the downstream pipe pressure corresponds to the pressure on the outlet 15b side of the solenoid valve 15. Furthermore, the downstream pipe pressure corresponds to the pressure applied to the solenoid valve 15.

[0016] The first sub-pipe 12a is equipped with a pressure sensor 16a that measures the upstream pipe pressure, and the second sub-pipe 12b is equipped with a pressure sensor 16b that measures the downstream pipe pressure. Although not shown, the gas pipe 12 is equipped with several check valves (safety valves). Furthermore, the FC power generation system 2 may be equipped with multiple pressure sensors in addition to those shown in FIG. 1.

[0017] The tank valves 14a and 14b, the inlet valve 22, and the electromagnetic valve 15 are controlled by a controller 30. The dotted arrows in the figure represent control lines. Measurement data from the pressure sensors 16a and 16b is sent to the controller 30.

[0018] Prior to supplying hydrogen gas from the hydrogen tanks 11a and 11b to the FC main body 21, the controller 30 controls the valves in the following procedure.

[0019] First, the controller 30 closes the inlet valve 22 and alternately opens and closes the tank valves 14a and 14b and the electromagnetic valve 15. More specifically, the controller 30 opens and closes the tank valves 14a and 14b with the electromagnetic valve 15 closed, and then opens and closes the electromagnetic valve 15 with the tank valves 14a and 14b closed. The controller 30 repeats this procedure.

[0020] When the controller 30 opens and closes the tank valves 14a and 14b while the solenoid valve 15 is closed, hydrogen gas flows into the first sub-pipe 12a, and the upstream pipe pressure (the internal pressure of the first sub-pipe 12a) rises to the internal pressure of the hydrogen tanks 11a and 11b. At this time, because the solenoid valve 15 is closed, the downstream pipe pressure (the internal pressure of the second sub-pipe 12b) does not change. When the controller 30 then opens and closes the solenoid valve 15 while the tank valves 14a and 14b are closed, the hydrogen gas in the first sub-pipe 12a spreads to the second sub-pipe 12b. As a result, the upstream pipe pressure decreases and the downstream pipe pressure increases. However, because the tank valves 14a and 14b are closed, the upstream pipe pressure and the downstream pipe pressure do not rise to the tank internal pressure.

[0021] When tank valves 14a, 14b and solenoid valve 15 are alternately opened and closed, downstream pipe pressure gradually increases. If tank valves 14a, 14b and solenoid valve 15 were opened simultaneously when downstream pipe pressure was atmospheric pressure, a large shock pressure would be generated at inlet valve 22, which could damage inlet valve 22. In the FC power generation system 2, the downstream pipe pressure gradually increases, so the shock pressure applied to inlet valve 22 is suppressed.

[0022] When the downstream pipe pressure reaches a predetermined threshold pressure, the controller 30 opens the tank valves 14a and 14b and the electromagnetic valve 15, and then opens the inlet valve 22. This process starts the supply of hydrogen gas from the hydrogen tanks 11a and 11b to the FC main body 21.

[0023] Here are some points to note regarding the technology described in the embodiment. When the tank valves 14a and 14b are opened while the solenoid valve 15 is closed, the upstream pipe pressure (the internal pressure of the first sub-pipe 12a) rises suddenly to the tank internal pressure. The solenoid valve 15 must be able to withstand this shock pressure. In other words, the shock pressure resistance of the solenoid valve 15 must be higher than the shock pressure resistance of the inlet valve 22. The solenoid valve 15 belongs to the hydrogen storage module 10. No matter what type of gas-utilizing device is connected to the hydrogen storage module 10, the inlet valve of the gas-utilizing device is protected.

[0024] It is preferable that first sub-pipe 12a be longer than second sub-pipe 12b. The longer first sub-pipe 12a is compared to second sub-pipe 12b, the smaller the increase in downstream pipe pressure when electromagnetic valve 15 is opened or closed. In other words, the longer first sub-pipe 12a is, the more gradually the downstream pipe pressure increases. The impact pressure applied to inlet valve 22 each time electromagnetic valve 15 is opened or closed is smaller.

[0025] The aforementioned threshold pressure is set to be equal to or lower than the internal pressure of the hydrogen tanks 11a, 11b (internal tank pressure). When the solenoid valve 15 is opened and closed after the tank valves 14a, 14b are opened and closed, the downstream pipe pressure increases by dP. Here, dP = "internal pressure of the hydrogen tanks 11a, 11b" x "length of the second sub-pipe 12b" / "length of the gas pipe 12". The threshold pressure is preferably set to be equal to or lower than the internal tank pressure and greater than "internal tank pressure - dP". When this condition is met, the increase in downstream pipe pressure does not exceed dP. The threshold pressure may be equal to the internal tank pressure.

[0026] Tank valves 14a, 14b and solenoid valve 15 may be simple on-off valves (stop valves) that can be in one of two states, "open" or "closed." Such valves are inexpensive. Inlet valve 22 may be a simple on-off valve (stop valve), or may be a pressure reducing valve (or pressure regulating valve). A pressure reducing valve (or pressure regulating valve) is a valve that can lower the pressure on the gas outlet side below the pressure on the gas inlet side. If the appropriate pressure range of hydrogen gas used by FC main body 21 is lower than the internal pressure of hydrogen tanks 11a, 11b, it is desirable to use a pressure reducing valve (or pressure regulating valve) as inlet valve 22.

[0027] Tank valves 14a and 14b are an example of a first valve. Inlet valve 22 is an example of a second valve. Solenoid valve 15 is an example of a third valve. The second valve may be a valve of a type other than "solenoid."

[0028] The controller 30 may open and close both of the tank valves 14a, 14b, or may keep one of the tank valves 14a, 14b closed while opening and closing the other. That is, the controller 30 may keep one of the tank valves 14a, 14b closed and alternately open and close the other tank valve and the solenoid valve 15. The controller 30 may keep one of the tank valves 14a, 14b closed while opening and closing the other, then open and close the solenoid valve 15, then open and close one of the tank valves 14a, 14b while keeping the other closed, and then open and close the solenoid valve 15.

[0029] The gas utilization device (FC power generation device 2) of the embodiment includes two hydrogen tanks 11a and 11b. The gas utilization device may include three or more gas tanks, or may include only one gas tank.

[0030] The FC power generation system 2 is an example of a gas utilization system. The FC main body 21 is an example of a gas utilization device. A typical example of a gas utilization system is a fuel cell vehicle equipped with a hydrogen gas tank and a fuel cell. The technology disclosed in this specification can be applied to any system equipped with a gas tank and a gas utilization device, and can also be applied to systems other than FC power generation systems. Furthermore, the gas utilization device may be a device other than the FC main body 21. The gas utilized may be a gas other than hydrogen gas. The gas utilization system disclosed in this specification is a system in which gas from a gas tank is supplied to the gas utilization device.

[0031] Although specific examples of the present invention 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 can achieve multiple objectives simultaneously, and achieving one of these objectives alone is technically useful. [Explanation of symbols]

[0032] 2: FC power generation device 10: Hydrogen storage module 11a, 11b: Hydrogen tank 12: Gas pipe 12a: First sub-pipe 12b: Second sub-pipe 14a, 14b: Tank valve 15: Solenoid valve 15a: Inlet 15b: Outlet 16a, 16b: Pressure sensor 20: FC unit 21: FC main body 22: Inlet valve 30: Controller 40: Fluid coupler

Claims

1. a gas tank having a first valve; a gas utilization device having a second valve; a gas pipe connecting the first valve and the second valve; a third valve provided in the gas pipe; a controller that alternately opens and closes the first valve and the third valve while keeping the second valve closed, and opens the first valve, the second valve, and the third valve when the internal pressure of the gas pipe between the second valve and the third valve reaches a predetermined threshold pressure; A gas utilization device comprising:

2. The gas utilization device according to claim 1 , wherein the impact pressure resistance of the third valve is higher than the impact pressure resistance of the second valve.

3. 3. The gas utilization device according to claim 1, wherein the first valve and the third valve are opening / closing valves that are switched between open and closed states, and the second valve is a pressure reducing valve that has a pressure on the outlet side lower than a pressure on the inlet side.

4. The gas utilization device according to claim 1, wherein the gas pipe includes a first sub-pipe connecting the first valve and the third valve, and a second sub-pipe connecting the third valve and the second valve, and the first sub-pipe is longer than the second sub-pipe.

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