JP2006144962A - Hydrogen gas supply system and moving body equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen gas supply system having simple construction for allowing the temperature rise of hydrogen gas whose temperature lowers with adiabatic expansion following depressurization. <P>SOLUTION: A high pressure hydrogen tank 21 is connected to a fuel cell stack 10 via a depressurizing valve 23 with a hydrogen gas supply pipe 22. The hydrogen gas supply pipe 22 has an extra pipe portion 30 1-2 meters longer than a shortest pipe line ranging from the depressurizing valve 23 to the fuel cell stack 10. The extra pipe portion 30 is partly formed by a meandering part of the hydrogen gas supply pipe 22. Such construction easily allows the temperature rise of hydrogen gas whose temperature suddenly lowers with adiabatic expansion following depressurization. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for supplying decompressed hydrogen gas to an internal combustion engine or a fuel cell that uses hydrogen gas as fuel.

  In a system that supplies hydrogen gas as a fuel gas from a high-pressure hydrogen tank, such as a fuel cell system mounted on a vehicle, the temperature of the hydrogen gas significantly decreases due to adiabatic expansion when the high-pressure hydrogen gas is depressurized. This phenomenon is known (for example, see Patent Document 1). For this reason, depending on the temperature of the lowered hydrogen gas, there is a possibility of affecting the durability and reliability of various parts and seal parts constituting the fuel cell.

  Therefore, in Patent Document 2 below, a hydrogen gas pipe that supplies hydrogen gas to the fuel cell and a cooling water discharge pipe that discharges water that has cooled the fuel cell main body are disposed adjacent to each other, so A technique for preheating hydrogen gas using heat is disclosed.

  However, in such a conventional technique, it is necessary to arrange two pipes having different functions adjacent to each other, so that it is difficult to adopt such arrangement in a limited space such as a vehicle. was there.

JP 2002-216812 A Japanese Utility Model Publication No. 1-77267

  The present invention has been made to solve such a problem, and an object of the present invention is to raise the temperature of hydrogen gas, which has been lowered by decompression, with a simple configuration.

Based on the above object, the present invention provides:
A hydrogen gas supply system that supplies the hydrogen gas to a hydrogen consuming device that consumes hydrogen gas,
Hydrogen gas storage means for storing high-pressure hydrogen gas;
Decompression means for decompressing the hydrogen gas;
A hydrogen gas supply pipe for supplying the hydrogen gas decompressed by the decompression means to the hydrogen consuming equipment,
The hydrogen gas supply pipe has a surplus pipe portion formed by bending a part thereof, and has a pipe length longer than a path length necessary for the pipe from the decompression means to the hydrogen consuming equipment. The gist.

  In the hydrogen gas supply system of the present invention, the hydrogen gas, which has become low temperature due to adiabatic expansion due to the decompression, passes through the surplus piping portion in the hydrogen supply piping, so that heat exchange with the outside air is performed and the temperature is raised. Since the specific heat of hydrogen is low, the hydrogen gas supply pipe is lengthened as in the present invention without forming a special shape such as forming the pipe in a bellows shape or providing a heat receiving fin on the surface thereof. The temperature can be easily raised with a simple configuration. For example, the length of the surplus piping part can be about 1 meter to 2 meters. With such a length, the specific heat of hydrogen is low, so that the hydrogen gas can be sufficiently heated.

In the hydrogen gas supply system configured as described above,
The surplus piping part may be formed by bending a part of the hydrogen gas supply piping into a meandering shape, a spiral shape, or a spiral shape.

  According to such a configuration, the surplus piping portion can be formed compactly and the length thereof can be ensured to be large. Accordingly, the area where the hydrogen gas supply pipe comes into contact with the outside air increases, and heat exchange can be performed efficiently.

In the hydrogen gas supply system configured as described above,
The hydrogen consuming device may be an internal combustion engine or a fuel cell using hydrogen gas as a fuel.

  According to such a configuration, it is possible to suppress deterioration of durability, reliability, and the like due to deterioration of various parts and seal portions constituting the internal combustion engine and the fuel cell due to the influence of hydrogen gas that has become low temperature. . Further, according to the present invention, the temperature of the hydrogen gas as the fuel can be raised, so that the combustion state of the hydrogen gas in the internal combustion engine and the power generation efficiency of the fuel cell can be improved.

  Moreover, this invention can be comprised also as a moving body provided with the hydrogen gas supply system mentioned above.

  There are cases where it is difficult to secure a space for mounting a device such as a heat exchanger because an internal combustion engine, a fuel cell, and various other auxiliary machines are mounted inside the moving body. Therefore, the effect of the present invention that can raise the temperature of hydrogen gas with a simple configuration is particularly high.

  Moreover, in such a moving body, the surplus piping part may be arranged at a position where the traveling wind hits.

  With such a configuration, the temperature of the hydrogen gas can be raised more efficiently by applying the traveling wind to the surplus piping part.

Hereinafter, embodiments of the present invention will be described based on examples.
FIG. 1 is an explanatory diagram illustrating a schematic configuration of a vehicle 100 as an embodiment. As shown in the figure, the vehicle 100 of this embodiment includes a fuel cell stack 10, a hydrogen supply system 20 that supplies hydrogen gas to the fuel cell stack 10, a motor 40, a control unit 50, and the like.

  The fuel cell stack 10 is a solid polymer fuel cell that generates electric power by an electrochemical reaction between hydrogen supplied from the hydrogen supply system 20 and oxygen in the air supplied from the blower 45. A motor 40 that is driven by the electric power generated by the fuel cell stack 10 is connected to the fuel cell stack 10. The motor 40 is used as a power source for driving the wheel 65 via the axle 60.

  The control unit 50 includes a CPU, RAM, and ROM. The CPU controls the operation of the vehicle 100 by executing a control program recorded in the ROM while using the RAM as a work area. An accelerator opening sensor 55 is connected to the control unit 50. The control unit 50 adjusts the amount of air supplied from the blower 45 and the amount of hydrogen supplied from the hydrogen supply system 20 according to the amount of depression of the accelerator detected by the driver by the accelerator opening sensor 55, and the fuel cell stack. 10 controls the amount of power generation.

  The hydrogen supply system 20 includes four high-pressure hydrogen tanks 21 and a hydrogen gas supply pipe 22. The high-pressure hydrogen tank 21 is connected to the hydrogen gas supply pipe 22 via a pressure reducing valve 23, a manual valve 24, and a shut valve 25, respectively. In addition, although the vehicle 100 of the present embodiment is provided with four high-pressure hydrogen tanks 21, the number thereof is arbitrary, and may be provided with one or two. Also, three may be provided. Of course, five or more may be provided.

  Hydrogen gas is stored in the high-pressure hydrogen tank 21 in a high-pressure state of 35 to 70 MPa. The pressure reducing valve 23 depressurizes the high-pressure hydrogen to a pressure required by the fuel cell stack 10, that is, a pressure of about 0.1 to 0.2 MPa. The manual valve 24 is a valve for manually stopping the supply of hydrogen gas to the fuel cell stack 10 in an emergency or the like. The shut valve 25 is a valve used to select a tank that actually supplies hydrogen to the fuel cell stack 10 among the four high-pressure hydrogen tanks based on an instruction from the control unit 50. The high-pressure hydrogen tank 21 is further connected to a hydrogen supply pipe 26 for receiving hydrogen gas supply from outside via check valves 27 and 28 and a manual valve 29.

  The hydrogen gas supply pipe 22 has a surplus pipe section 30 so that its pipe length is about 1 to 2 meters longer than the shortest pipe path from the pressure reducing valve 23 to the fuel cell stack 10. The surplus pipe part 30 is formed by bending a part of the hydrogen gas supply pipe 22 in a meandering manner. If it is such a shape, since the excess piping part 30 can be formed compactly, it can be efficiently accommodated in the limited space in the vehicle 100.

  In the vehicle 100 of the present embodiment configured as described above, the hydrogen gas output from the high-pressure hydrogen tank 21 is rapidly depressurized by the pressure reducing valve 23, and the temperature thereof is significantly lowered by adiabatic expansion. However, the hydrogen gas passes through the surplus pipe part 30 provided in the path of the hydrogen gas supply pipe 22, whereby the heat exchange with the outside air is promoted and the temperature is increased. Since hydrogen has a small specific heat, the surplus piping section 30 is not provided in a special piping shape such as forming the hydrogen gas supply pipe 22 in a bellows shape or providing a heat receiving fin on the surface. The temperature can be easily raised with a simple configuration in which the length of the hydrogen gas supply pipe 22 is increased. As a result, it is possible to suppress deterioration of durability and reliability due to deterioration of various parts and seal portions constituting the fuel cell stack 10 by low-temperature hydrogen gas.

  As mentioned above, although the Example of this invention was described, this invention is not limited to such an Example at all, Of course, it can implement with a various form within the range which does not deviate from the meaning. For example, in the above embodiment, the hydrogen supply system 20 is mounted on the vehicle 100. However, the hydrogen supply system 20 may be provided in a stationary fuel cell system. The hydrogen supply system 20 can also be used for the purpose of supplying hydrogen gas to an internal combustion engine that obtains driving force by burning hydrogen gas. In addition, the following modifications are possible.

(Modification 1)
FIG. 2 and FIG. 3 are explanatory diagrams showing modifications of the surplus piping part 30. In the above-described embodiment, the surplus pipe part 30 is formed by bending a part of the hydrogen gas supply pipe 22 in a meandering manner. On the other hand, the surplus pipe part 30b in FIG. A part was formed by bending in a spiral. 4 is formed by bending a part of the hydrogen gas supply pipe 22 into a spiral shape. Even if it is these shapes, the piping length of the hydrogen gas supply piping 22 can be lengthened, and heat exchange with outside air can be accelerated | stimulated.

(Modification 2)
FIG. 4 is an explanatory view showing a modified example of the vehicle 100. The vehicle 100b according to this modification is configured such that a duct 70 and a fan 80 for introducing traveling wind are installed toward the surplus piping part 30 as illustrated. With such a configuration, heat exchange can be further promoted. If the temperature of the hydrogen gas is about 10 ° C. lower than the outside air temperature, there is no hindrance to power generation, so that sufficient heat exchange can be performed by the traveling wind. Further, the temperature of the hydrogen gas supplied from the high-pressure hydrogen tank 21 decreases as the load increases, such as when the fuel cell stack 10 requires a larger amount of hydrogen gas during high-speed travel. However, even in such a case, if the vehicle is traveling at a high speed, a sufficient amount of traveling airflow for heat exchange can be obtained, so that the hydrogen gas can be sufficiently heated. In this modification, both the duct 70 and the fan 80 are provided. However, only one of them may be provided. Moreover, it is good also as what takes the simple structure of arrange | positioning the surplus piping part 30 in the position where driving wind hits, without providing the duct 70 and the fan 80. FIG.

(Modification 3)
FIGS. 5A and 5B are explanatory views showing a modification of the hydrogen gas supply pipe 22. In the above-described embodiments and modifications, a part of the hydrogen gas supply pipe 22 is bent to form the serpentine or spiral surplus pipe section 30. On the other hand, in this modified example, the hydrogen gas supply pipe 22 is turned around so as to be longer than the shortest path connecting the fuel cell stack 10 and the high-pressure hydrogen tank 21. Also by doing this, the heat exchange with the outside air can be promoted to raise the temperature of the hydrogen gas. In this way, if the pipe is detoured and its pipe length is increased, a space is opened between the fuel cell stack 10 and the high-pressure hydrogen tank 21 (inside the broken line in the figure), so that the pipe is mounted on the vehicle. Various devices can be arranged with a high degree of freedom.

2 is an explanatory diagram showing a schematic configuration of a vehicle 100. FIG. It is explanatory drawing which shows the modification of the surplus piping part. It is explanatory drawing which shows the modification of the surplus piping part. FIG. 11 is an explanatory diagram showing a modified example of the vehicle 100. It is explanatory drawing which shows the modification of the hydrogen gas supply piping.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Vehicle 10 ... Fuel cell stack 20 ... Hydrogen supply system 21 ... High-pressure hydrogen tank 22 ... Hydrogen gas supply piping 23 ... Pressure reducing valve 24 ... Manual valve 25 ... Shut valve 26 ... Hydrogen supply piping 27,28 ... Check valve 29 ... Manual valve 30 ... Excess piping 40 ... Motor 45 ... Blower 50 ... Control unit 55 .. Accelerator opening sensor 60 ... Axle 65 ... Wheel 70 ... Duct 80 ... Fan

Claims (5)

A hydrogen gas supply system that supplies the hydrogen gas to a hydrogen consuming device that consumes hydrogen gas,
Hydrogen gas storage means for storing high-pressure hydrogen gas;
Decompression means for decompressing the hydrogen gas;
A hydrogen gas supply pipe for supplying the hydrogen gas decompressed by the decompression means to the hydrogen consuming equipment,
The hydrogen gas supply pipe has a surplus pipe part formed by bending a part thereof, and has a pipe length longer than the path length necessary for the pipe from the decompression means to the hydrogen consuming equipment. Supply system. The hydrogen gas supply system according to claim 1,
The surplus pipe part is formed by bending a part of the hydrogen gas supply pipe in a meandering shape, a spiral shape, or a spiral shape. The hydrogen gas supply system according to claim 1 or 2,
The hydrogen consuming device is an internal combustion engine or a fuel cell using hydrogen gas as a fuel.   A moving body comprising the hydrogen gas supply system according to claim 1. The moving body according to claim 4,
The surplus piping part is arranged at a position where the traveling wind hits.

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