JP2019102266A - Fuel cell system - Google Patents

Abstract

To provide a fuel cell system having high safety.SOLUTION: A fuel cell system (100) comprises: a frame (20) installed outside a building (10); a fuel cell unit (30) disposed inside the frame (20); a gas supply path (40) for supplying combustible gas to the fuel cell unit (30); and a cutoff valve (42) provided on the gas supply path (40). The cutoff valve (42) is closed in at least one case selected from a case in which a temperature of the frame (20) exceeds a frame threshold temperature, a case in which a temperature in the periphery of the frame (20) exceeds a peripheral threshold temperature, and a case in which a temperature of an outer wall (12) of the building (10) exceeds a building threshold temperature.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fuel cell system.

  Conventionally, a fuel cell system of this type may be provided with a thermal fuse in order to prevent a fire from occurring due to leakage of combustible gas, abnormal heating of a heater or the like (for example, Patent Document 1). Thermal fuses are provided in the system and blow when the temperature in the system exceeds an acceptable range. In response to the disconnection of the thermal fuse, the fuel shutoff valve is closed.

JP, 2014-26873, A

  However, in the above-described conventional configuration, only a thermal fuse is provided in the system. Therefore, the conventional configuration has a problem in that it is not possible to promptly detect any external change such as a fire of a building, and the safety can not be sufficiently secured.

  The present invention solves the above-mentioned conventional problems, and an object thereof is to provide a fuel cell system having high safety.

In order to solve the above-mentioned conventional problems, the fuel cell system of the present invention is
A housing installed outside the building,
A fuel cell unit disposed inside the housing;
A gas supply path for supplying a flammable gas to the fuel cell unit;
A shutoff valve provided in the gas supply path;
Equipped with
If the temperature of the case exceeds the case threshold temperature, if the temperature around the case exceeds the ambient threshold temperature, and if the temperature of the outer wall of the building exceeds the building threshold temperature The shutoff valve is closed in at least one case.

  In the fuel cell system of the present invention, when the temperature of the case exceeds the case threshold temperature, when the temperature around the case exceeds the ambient threshold temperature, and the temperature of the outer wall of the building exceeds the building threshold temperature The shutoff valve is closed in at least one of the selected cases. The supply of flammable gas can be stopped promptly in response to external changes such as a fire in a building. Therefore, according to the present invention, a fuel cell system having high safety can be provided.

Diagram of fuel cell system according to the first embodiment of the present invention Configuration of fuel cell system according to modification 1 Configuration of fuel cell system according to modification 2 Configuration of fuel cell system according to modification 3 Configuration of fuel cell system according to modification 4 Configuration of fuel cell system according to Embodiment 2 of the present invention Configuration of fuel cell system according to modification 5 Configuration of fuel cell system according to modification 6 Configuration of fuel cell system according to modification 7 Structure view of a fuel cell system according to Embodiment 3 of the present invention A configuration diagram of a fuel cell system according to a fourth embodiment of the present invention Configuration of fuel cell system according to modification 8 Structure view of a fuel cell system according to Embodiment 5 of the present invention

  According to a first aspect of the present invention, there is provided a housing installed outside a building, a fuel cell unit disposed inside the housing, a gas supply path for supplying a flammable gas to the fuel cell unit, and A fuel cell system comprising a shutoff valve provided in a gas supply path, wherein when the temperature of the case exceeds a case threshold temperature, the temperature around the case exceeds the ambient threshold temperature In the case where the temperature of the outer wall of the building exceeds the building threshold temperature, and in at least one case where it is selected, the shutoff valve is closed. According to the first invention, when the temperature of the housing exceeds the housing threshold temperature, when the temperature around the housing exceeds the ambient threshold temperature, and the temperature of the outer wall of the building exceeds the building threshold temperature The shutoff valve is closed in at least one of the selected cases. The supply of flammable gas can be stopped promptly in response to external changes such as a fire in a building. Therefore, according to the first invention, a fuel cell system having high safety can be provided.

  In the second invention, in particular, in the fuel cell system according to the first invention, when the temperature of the case exceeds a case threshold temperature, the temperature around the case exceeds the ambient threshold temperature; A protective feature may be provided that operates to close the shutoff valve in at least one case where it is selected from the case where the temperature of the outer wall of the building exceeds the building threshold temperature. According to the protection function unit, the supply of the flammable gas can be promptly stopped in response to an external change such as a fire of the building.

  In the third invention, in particular, the protective function part of the second invention may include at least one selected from a thermal fuse and a thermo switch. Thermal fuses and thermoswitches are devices that do not require power and control and have high reliability. Therefore, using these devices, the shutoff valve can be reliably closed in response to external changes such as a building fire.

  In the fourth invention, in particular, the protection function part of the second or third invention may be located on a power supply circuit connected to the shutoff valve. According to such a configuration, since it is not necessary to exchange signals with other circuits such as the control unit, the shutoff valve can be reliably closed in an emergency.

  In the fifth invention, in particular, the fuel cell system according to the first invention may further include a control unit and a temperature sensor for detecting the temperature of the housing, and the control unit is the temperature sensor. The shutoff valve may be closed when the temperature of the housing detected by the threshold exceeds the housing threshold temperature. Also in the fifth invention, the supply of the flammable gas can be promptly stopped in response to an external abnormality such as a fire of a building.

  In the sixth invention, in particular, the fuel cell system according to the first invention may further include a control unit and a temperature sensor for detecting the temperature around the casing, and the control unit The shutoff valve may be closed when the ambient temperature detected by the temperature sensor exceeds the ambient threshold temperature. Also in the sixth aspect of the invention, the supply of the flammable gas can be promptly stopped in response to an external abnormality such as a fire of a building.

  In the seventh invention, in particular, the fuel cell system according to the first invention may further include a control unit and a temperature sensor for detecting the temperature of the outer wall of the building, the control unit further comprising: The shutoff valve may be closed when the temperature of the exterior wall of the building detected by a temperature sensor exceeds the building threshold temperature. Also in the sixth aspect of the invention, the supply of the flammable gas can be promptly stopped in response to an external abnormality such as a fire of a building.

  In the eighth invention, in particular, the protective function part or the temperature sensor of any one of the second to seventh inventions may be attached to the inner surface of the housing. According to such a configuration, it is possible to reliably detect external variations while protecting the protection function unit from physical damage or the like.

  In the ninth invention, in particular, the inner surface of the housing of the eighth invention may be an inner surface of a wall portion of the housing facing the building. According to the ninth aspect of the invention, the supply of the flammable gas can be promptly stopped by reacting quickly to the temperature rise. As a result, the safety of the fuel cell system can be further enhanced.

  In a tenth aspect of the invention, in particular, the temperature sensor according to any one of the fifth to seventh aspects of the invention is disposed inside the housing, and the temperature of the housing from the inside of the housing, The temperature of the surrounding of the housing or the temperature of the outer wall of the building is detected. According to such a configuration, it is possible to reliably detect an external change while protecting the temperature sensor from physical damage and the like. As a result, the reliability and safety of the fuel cell system is also enhanced.

  In the eleventh invention, in particular, the protective function unit or the temperature sensor according to any one of the second to seventh inventions may be disposed outside the housing. According to such a configuration, it is possible to directly and reliably detect an external anomaly such as a fire of a building.

  In the twelfth invention, in particular, the protective function part or the temperature sensor of any one of the second to seventh inventions may be attached to the outer surface of the housing. According to such a configuration, it is possible to more reliably detect an external anomaly such as a fire of a building.

  In the thirteenth invention, in particular, the outer surface of the housing of the twelfth invention may be an outer surface of a wall portion of the housing facing the building. According to the thirteenth aspect of the present invention, the supply of the flammable gas can be quickly stopped by reacting quickly to the temperature rise. As a result, the safety of the fuel cell system can be further enhanced.

  In the fourteenth invention, in particular, the protective function part or the temperature sensor of any one of the second to seventh inventions may be attached to the outer wall of the building. According to such a configuration, the temperature of the outer wall of the building can be directly detected. Therefore, it is possible to quickly detect a change in a building.

  In the fifteenth invention, in particular, the case of any one of the second to fifth inventions may be in contact with the building, and the protection function unit or the temperature sensor may be the case and the case. The temperature of the housing may be detected at a contact position with a building. According to the fifteenth invention, since the temperature of the housing at the contact position between the building and the housing is detected, it is possible to more reliably detect an external change such as a fire of the building. As a result, the safety of the fuel cell system is enhanced.

  In the sixteenth invention, in particular, the shutoff valve of any one of the first to fifteenth inventions may be disposed inside the housing. In this case, the shutoff valve can be reliably protected from the external environment.

  In the seventeenth invention, in particular, the shutoff valve of any one of the first to fifteenth inventions may be disposed outside the housing. In this case, the supply of flammable gas can be stopped at a position sufficiently away from the building. Therefore, according to the seventeenth invention, higher security can be ensured.

In the eighteenth invention, in particular, the fuel cell unit according to any one of the first to seventeenth inventions may include a fuel cell stack, and the gas supply path is connected to the fuel cell stack The fuel cell stack may be supplied with hydrogen gas as the flammable gas through the gas supply path. A pure hydrogen fuel cell system is advantageous for miniaturization as it does not require a reformer. Also, a pure hydrogen fuel cell system can achieve high power generation efficiency and can also be rapidly started up. By using hydrogen gas derived from renewable energy, a complete CO ₂ free system can be constructed.

  In the nineteenth invention, in particular, the fuel cell unit according to any one of the first to seventeenth inventions may include a fuel cell stack and a reformer, and the gas supply path may include The raw material gas as the combustible gas may be supplied to the reformer through the gas supply path, and the reformer reacts the raw material gas with water. To generate a hydrogen-containing gas to be supplied to the fuel cell stack. The fuel cell system of the nineteenth invention does not require a hydrogen gas source such as a hydrogen storage tank, so it can be easily introduced to small-scale facilities such as houses and multi-family dwellings.

  In the twentieth invention, in particular, the shutoff valve of any one of the first to nineteenth inventions may be a valve which is open when energized and closed when deenergized. This type of valve is excellent in terms of safety.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited by the present embodiment.

Embodiment 1
FIG. 1 shows the configuration of a fuel cell system according to Embodiment 1 of the present invention. The fuel cell system 100 includes a housing 20, a fuel cell unit 30, and a gas supply path 40. The housing 20 is installed outside the building 10. That is, the fuel cell system 100 is installed outside the building 10. A space of an appropriate size is secured between the building 10 and the housing 20. The fuel cell unit 30 is disposed inside the housing 20. The gas supply path 40 is connected to the fuel cell unit 30 and extends outside the housing 20. The gas supply path 40 is provided with a shutoff valve 42. The shutoff valve 42 is located inside the housing 20. The combustible gas is supplied to the fuel cell unit 30 through the gas supply path 40. The flammable gas is, for example, hydrogen gas.

The fuel cell system 100 is, for example, a pure hydrogen fuel cell system. When the fuel cell system 100 is a pure hydrogen fuel cell system, the fuel cell unit 30 includes a fuel cell stack 30a and various peripheral devices 30c. The fuel cell stack 30a generates electric power using the fuel gas and the oxidant gas. In the present embodiment, the hydrogen gas is a fuel gas, and the air is an oxidant gas. The fuel cell stack 30a may be in solid polymer form or in solid oxide form. Examples of peripherals 30c include pumps, valves, heat exchangers, heaters and sensors. The gas supply path 40 is connected to the fuel cell stack 30a. A hydrogen gas as a flammable gas is supplied to the fuel cell stack 30a from a hydrogen gas source (not shown) such as a hydrogen storage tank through the gas supply path 40. The gas supply path 40 may be provided with another device such as a desulfurizer. A pure hydrogen fuel cell system is advantageous for miniaturization as it does not require a reformer. Also, a pure hydrogen fuel cell system can achieve high power generation efficiency and can also be rapidly started up. By using hydrogen gas derived from renewable energy, a complete CO ₂ free system can be constructed.

  The power generated in the fuel cell system 100 may be supplied to the building 10 or may be supplied to other facilities such as a commercial power transmission facility. The type of the building 10 is not particularly limited. Examples of buildings 10 include houses, apartment buildings, commercial facilities, public facilities, accommodation facilities, office buildings, residential buildings, warehouses and factories.

  The fuel cell system 100 further includes a control unit 32 and a power supply circuit 34. The control unit 32 and the power supply circuit 34 are disposed inside the housing 20. The control unit 32 may be disposed outside the housing 20. The power supply circuit 34 may be disposed outside the housing 20.

  The control unit 32 controls control targets such as the shutoff valve 42 and the peripheral device 30c. As the control unit 32, a DSP (Digital Signal Processor) including an A / D conversion circuit, an input / output circuit, an arithmetic circuit, and a storage device can be used. The control unit 32 stores a program for operating the fuel cell system 100 properly. The power supply circuit 34 is responsible for supplying the power generated in the fuel cell stack 30a to the external and peripheral devices 30c. Power is supplied from the power supply circuit 34 to the shutoff valve 42 through the power supply circuit 37.

  In the fuel cell system 100, the shutoff valve 42 is closed when the temperature of the housing 20 exceeds the housing threshold temperature. According to the present embodiment, the supply of hydrogen gas can be promptly stopped in response to external changes such as a fire of the building 10. In the present embodiment, the housing 20 has a plurality of wall portions 21, 22, 23 and 24. The housing 20 is made of metal, for example. The temperature of the housing 20 may be the temperature of the wall portions 21, 22, 23 or 24 constituting the housing 20. The temperature of the walls 21, 22, 23 or 24 of the housing 20 can be detected by direct contact or heat radiation.

  Specifically, the fuel cell system 100 includes a protection function unit 36. The protection function unit 36 operates to close the shutoff valve 42 when the temperature of the housing 20 exceeds the housing threshold temperature. According to the protection function unit 36, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10.

  In the present embodiment, the protection function unit 36 has at least one selected from a thermal fuse and a thermo switch. Thermal fuses and thermoswitches are devices that do not require power and control and have high reliability. Therefore, if these devices are used, the shutoff valve 42 can be reliably closed in response to external changes such as a fire of the building 10.

  A thermal fuse is a device equipped with a fusible material that melts when the temperature rises. The soluble form is made of, for example, low melting point metal and resin. The thermo switch may be a switch using bimetal (so-called bimetal thermostud), or may be a switch using a PTC thermistor (Positive Temperature Coefficient Thermistor). A switch using bimetal is a device utilizing displacement of the bimetal by heat. A switch using a PTC thermistor is a device that utilizes the characteristic of a PTC thermistor whose resistance rises rapidly when the set temperature is exceeded. The thermo switch returns when the temperature drops after operation. On the other hand, the thermal fuse does not recover after operation. The thermoswitch is advantageous in that maintenance can be simplified. The thermal fuse is advantageous in that high reliability and high safety can be ensured.

  In the present embodiment, the protection function unit 36 is located on the power supply circuit 37 connected to the shutoff valve 42. The power supply circuit 37 connects the power supply circuit 34 and the shutoff valve 42. When the protection function unit 36 operates at the set temperature, the power supply circuit 37 is opened, the power supply to the shutoff valve 42 is stopped, and the shutoff valve 42 is closed. Alternatively, when the protection function unit 36 operates at the set temperature, the power supply to the shutoff valve 42 is insufficient, and the shutoff valve 42 is closed. According to such a configuration, since it is not necessary to exchange signals with other circuits such as the control unit 32, the shutoff valve 42 can be reliably closed in an emergency.

  However, it is not essential that the protection function unit 36 be located on the power supply circuit 37. For example, the protection function unit 36 may constitute a part of the power supply circuit 34. Depending on the operation of the protection function unit 36, the power supply to the entire fuel cell system 100 may be cut off. Alternatively, when the control unit 32 detects that the protection function unit 36 operates at the set temperature, the control unit 32 may execute an electrical process for closing the shutoff valve 42.

  In the present embodiment, the protection function unit 36 is attached to the inner surface 21 p of the housing 20. According to such a configuration, it is possible to reliably detect an external change while protecting the protection function unit 36 from physical damage or the like. The protective function portion 36 may be in contact with the inner surface 21 p, or a gap may exist between the protective function portion 36 and the inner surface 21 p. When the protection function portion 36 is in contact with the inner surface 21 p, the protection function portion 36 can detect the temperature of the housing 20 by direct heat conduction. If there is a gap between the protection function portion 36 and the inner surface 21 p, the protection function portion 36 can detect the temperature of the housing 20 by heat radiation. In other words, the width of the gap may be a width that sufficiently transfers heat to the protection function portion 36 by heat radiation.

  In the present embodiment, the housing 20 is composed of a plurality of wall portions 21 to 24. The wall 21 is a portion facing the building 10. The wall 22 is a ceiling of the housing 20. The wall 23 is the bottom of the housing 20. The wall 24 faces the wall 21. In the present embodiment, the protection function portion 36 is attached to the inner surface 21 p of the wall portion 21. The wall 21 is the closest part to the building 10, and if a fire occurs in the building 10, the wall 21 is likely to be heated first. Therefore, when the protective function portion 36 is attached to the wall portion 21, the supply of hydrogen gas can be promptly stopped by reacting quickly to the temperature rise. As a result, the safety of the fuel cell system 100 can be further enhanced.

  Of course, the protection function portion 36 may be attached to the inner surface of the wall portions 22, 23 and 24 not facing the building 10. For example, when the fuel cell system 100 is installed on the roof of the building 10, the protection function portion 36 may be attached to the inner surface of the wall 23 which is the bottom of the housing 20. In this case, there is a possibility that the external abnormality such as the fire of the building 10 can be detected most quickly. Further, when the case 20 is made of metal, heat is conducted to the entire case 20 promptly.

  According to the present embodiment, the shutoff valve 42 is closed when the temperature of the housing 20 exceeds the housing threshold temperature. The housing threshold temperature is determined according to conditions such as the distance between the building 10 and the housing 20, the position of the protection function unit 36, and the like. In one example, the housing threshold temperature is a temperature set in the range of 90 to 110 ° C.

  In the present embodiment, the shutoff valve 42 is a valve that is open when energized and closed when not energized. This type of valve is excellent in terms of safety. Moreover, this type of valve is excellent in compatibility with the protection function portion 36. The shutoff valve 42 is typically a solenoid valve. The shutoff valve 42 is supplied with power from the power supply circuit 34 through the power supply circuit 37. The control unit 32 controls the opening and closing of the shutoff valve 42 directly or via the power supply circuit 34.

  In the present embodiment, the shutoff valve 42 is disposed inside the housing 20. In this case, the shutoff valve can be reliably protected from the external environment.

  Hereinafter, other embodiments and modifications will be described. Common elements between the fuel cell system 100 of the first embodiment and the other fuel cell systems may be assigned the same reference numerals and descriptions thereof may be omitted. The description of each embodiment and each modification can be applied to each other as long as there is no technical contradiction. The embodiments and modifications may be combined with each other as long as no technical contradiction arises.

(Modification 1)
FIG. 2 shows the configuration of the fuel cell system according to the first modification. The fuel cell system 102 according to the first modification is a fuel cell system provided with a reformer 30 b. In the fuel cell system 102, the fuel cell unit 30 includes a fuel cell stack 30a, a reformer 30b, and various peripheral devices 30c. The gas supply path 40 is connected to the reformer 30 b. A raw material gas as a flammable gas is supplied to the reformer 30 b from a raw gas source (not shown) such as a city gas infrastructure through the gas supply path 40. The reformer 30b causes the raw material gas and water to react to generate a hydrogen-containing gas to be supplied to the fuel cell stack 30a. The source gas is, for example, a hydrocarbon gas such as methane gas or propane gas. Also in the present modification, the supply of the source gas can be promptly stopped in response to an external change such as a fire of the building 10. The fuel cell system 102 according to the present modification does not require a hydrogen gas source such as a hydrogen storage tank, so it can be easily introduced to small-scale facilities such as a house and an apartment house.

  The configuration of this modification can be applied to the other embodiments and other modifications.

(Modification 2)
FIG. 3 shows the configuration of a fuel cell system according to a second modification. The fuel cell system 104 according to the second modification includes a temperature sensor 44 that detects the temperature of the housing 20 in place of the protection function unit 36. The temperature sensor 44 is attached to the inner surface 21 p of the housing 20. The temperature sensor 44 is electrically connected to the control unit 32. A detection signal of the temperature sensor 44 is input to the control unit 32. The control unit 32 closes the shutoff valve 42 when the temperature of the housing 20 detected by the temperature sensor 44 exceeds the housing threshold temperature. According to this modification, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10.

  The type of the temperature sensor 44 is not particularly limited. The temperature sensor 44 may be a contact sensor or a non-contact sensor. Examples of contact sensors include a temperature sensor using a thermistor and a temperature sensor using a thermocouple. Examples of non-contact sensors include infrared temperature sensors and thermo viewers.

  Along with the temperature sensor 44, a protective function unit 36 may be provided. For example, the control unit 32 closes the shutoff valve 42 when the temperature of the housing 20 detected by the temperature sensor 44 exceeds the first housing threshold temperature. The protection function unit 36 operates to close the shutoff valve 42 when the temperature of the housing 20 exceeds the second housing threshold temperature. The second housing threshold temperature may be set to a temperature higher than the first housing threshold temperature. In this case, since the protection function unit 36 functions as a final safety device that complements the temperature sensor 44, the safety of the fuel cell system 104 can be further enhanced.

  The control unit 32 controls the opening and closing of the shutoff valve 42 by executing a predetermined program. However, the control unit 32 may be an electronic circuit specially designed so that the shutoff valve 42 is closed when the temperature of the housing 20 detected by the temperature sensor 44 exceeds the housing threshold temperature. Control of the shutoff valve 42 by software is not essential.

  The configuration of this modification can be applied to the other embodiments and other modifications.

(Modification 3)
FIG. 4 shows the configuration of a fuel cell system according to a third modification. In the fuel cell system 106 according to the third modification, the shutoff valve 42 is disposed outside the housing 20. In this case, the supply of hydrogen gas can be stopped at a position sufficiently away from the building 10. Therefore, according to this modification, higher security can be ensured. The gas supply path 40 may extend in the direction in which the building 10 does not exist.

  The configuration of this modification can be applied to the other embodiments and other modifications.

(Modification 4)
FIG. 5 shows the configuration of a fuel cell system according to a fourth modification. In the fuel cell system 108 according to the fourth modification, the shutoff valve 42 may be a valve operated by the pressure of the control gas. The fuel cell system 108 includes a gas supply device 46 that supplies control gas to the shutoff valve 42. A control gas is supplied from the gas supply device 46 to the shutoff valve 42 through the gas supply pipe 47. The control gas is not particularly limited. The control gas is typically air.

  The protection function unit 36 is located, for example, on the power supply circuit 38 connected to the gas supply unit 46. When the protection function unit 36 operates, the power supply circuit 38 is opened, the power supply to the gas supply unit 46 is stopped, the supply of control gas from the gas supply unit 46 to the shutoff valve 42 is stopped, and the shutoff valve 42 is closed. . Alternatively, when the protection function unit 36 operates, the power supply to the gas supply unit 46 is insufficient, the gas supply unit 46 is stopped, and the supply of control gas from the gas supply unit 46 to the shutoff valve 42 is stopped. Is closed. According to such a configuration, since it is not necessary to exchange signals with other circuits such as the control unit 32, the shutoff valve 42 can be reliably closed in an emergency.

  The configuration of this modification can be applied to the other embodiments and other modifications. That is, the type of the shutoff valve 42 is not particularly limited in the other embodiments and other modifications.

Second Embodiment
FIG. 6 shows the configuration of a fuel cell system according to Embodiment 2 of the present invention. In the fuel cell system 200, the protection function unit 36 is disposed outside the housing 20. According to such a configuration, it is possible to directly and reliably detect an external change such as a fire of the building 10. The housing 20 is fixed to the building 10 by a plurality of brackets 48. The fitting 48 may be part of the housing 20. The configuration and function of the protection function unit 36 are as described in the first embodiment. Only one fitting 48 may be provided.

  In the present embodiment, the protection function unit 36 is attached to the outer surface 21 q of the housing 20. According to such a configuration, it is possible to more reliably detect an external change such as a fire of the building 10. The protective function portion 36 may be in contact with the outer surface 21 q, or a gap may exist between the protective function portion 36 and the outer surface 21 q. When the protection function portion 36 is in contact with the outer surface 21 q, the protection function portion 36 can detect the temperature of the housing 20 by direct heat conduction. When the protection function portion 36 is in contact with the fitting 48, the protection function portion 36 can detect the temperature of the fitting 48 which is a part of the housing 20. When there is a gap between the protection function portion 36 and the outer surface 21 q, the protection function portion 36 can detect the temperature around the housing 20.

  When the protection function unit 36 detects the temperature of the case 20, the protection function unit 36 operates when the temperature of the case 20 exceeds the case threshold temperature. Thereby, the shutoff valve 42 is closed. When the protection function unit 36 detects the temperature around the housing 20, the protection function unit 36 operates when the temperature around the housing 20 exceeds the ambient threshold temperature. Thereby, the shutoff valve 42 is closed. In any case, according to the present embodiment, the supply of hydrogen gas can be promptly stopped in response to external changes such as a fire of the building 10.

  According to the present embodiment, the shutoff valve 42 is closed when the temperature of the housing 20 exceeds the housing threshold temperature or when the temperature around the housing 20 exceeds the ambient threshold temperature. An example of the housing threshold temperature is as described in the first embodiment. The ambient threshold temperature is also determined according to conditions such as the distance between the building 10 and the housing 20, the position of the protection function unit 36, and the like. In one example, the ambient threshold temperature is a temperature set in the range of 100-120.degree. The “periphery of the housing 20” may be an area within 5 m from the housing 20, or may be an area within 3 m. The temperature around the housing 20 may be the temperature measured in such an area (space or ground). By setting such a region, a temperature rise due to heat radiation from the building 10 or a flame extending from the building 10 to the outside can be reliably detected.

  In the present embodiment, the protection function portion 36 is attached to the outer surface 21 q of the wall portion 21 of the housing 20. The outer surface 21 q is an outer surface of the wall 21 of the housing 20 facing the building 10. The wall 21 is the closest part to the building 10, and if a fire occurs in the building 10, the wall 21 is likely to be heated first. Therefore, when the protective function portion 36 is attached to the wall portion 21, the supply of hydrogen gas can be promptly stopped by reacting quickly to the temperature rise. As a result, the safety of the fuel cell system 200 can be further enhanced.

  Of course, the protection function portion 36 may be attached to the outer surfaces of the other wall portions 22, 23 and 24.

(Modification 5)
FIG. 7 shows the configuration of a fuel cell system according to the fifth modification. The fuel cell system 202 according to the fifth modification includes a temperature sensor 44 in place of the protection function unit 36. The temperature sensor 44 is attached to, for example, the outer surface 21 q of the housing 20. The temperature sensor 44 is electrically connected to the control unit 32, and a detection signal of the temperature sensor 44 is input to the control unit 32. The temperature sensor 44 may detect the temperature of the wall 21 of the housing 20, or may detect the temperature around the housing 20, and detects the temperature of the outer wall of the building 10. It may be one. When the temperature of the housing 20 exceeds the housing threshold temperature, or when the temperature around the housing 20 exceeds the ambient threshold temperature, the controller 32 controls the temperature of the outer wall 12 of the building 10 to the building threshold temperature. When it is exceeded, the shutoff valve 42 is closed. According to this modification, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10.

  The building threshold temperature is also determined according to conditions such as the material of the outer wall 12 of the building 10, the distance between the building 10 and the housing 20, and the position of the protection function unit 36. In one example, the building threshold temperature is a temperature set in the range of 120-150 ° C.

  The type of the temperature sensor 44 is not particularly limited. A specific example of the temperature sensor 44 is as described in the second modification. For example, a contact-type temperature sensor is suitable for detecting the temperature of the housing 20. The non-contact temperature sensor is suitable for detecting the temperature around the housing 20 or the temperature of the outer wall of the building 10. In place of the temperature sensor 44 or together with the temperature sensor 44, it is also possible to use a flame sensor. The flame sensor may be a sensor that detects weak light of a specific wavelength contained in the flame, and recognizes the presence of the flame by analyzing the infrared spectral pattern contained in the light emitted from the flame It may be a sensor. The shutoff valve 42 may be closed when the presence of a flame is recognized around the housing 20.

  Instead of the temperature sensor 44 or together with the temperature sensor 44, a protective function unit 36 may be provided.

  The configuration of this modification can be applied to the other embodiments and other modifications.

(Modification 6)
FIG. 8 shows the configuration of a fuel cell system according to the sixth modification. In the fuel cell system 204 according to the sixth modification, the protection function portion 36 is attached to the outer surface 22 q of the wall portion 22 of the housing 20. The wall 22 is a wall not facing the building 10. In the present modification, the wall portion 22 is a ceiling portion of the housing 20. For example, when a fire occurs in the building 10, not only the wall 21 facing the building 10 but also the entire housing 20 is likely to be heated. In this respect, the wall to which the protective function portion 36 is to be attached is not limited to the wall 21 facing the building 10.

  The protection function portion 36 may be in contact with the outer surface 22 q, or a gap may exist between the protection function portion 36 and the outer surface 22 q. When the protection function portion 36 is in contact with the outer surface 22 q, the protection function portion 36 can detect the temperature of the housing 20 by direct heat conduction. When there is a gap between the protection function portion 36 and the outer surface 22 q, the protection function portion 36 can detect the temperature around the housing 20.

  A temperature sensor 44 may be provided instead of the protective function unit 36 or together with the protective function unit 36.

(Modification 7)
FIG. 9 shows the configuration of a fuel cell system according to the seventh modification. In the fuel cell system 206 according to the seventh modification, the protection function unit 36 is disposed in the space between the building 10 and the housing 20. When the temperature around the housing 20 exceeds the ambient threshold temperature, the shutoff valve 42 is closed. According to this modification, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10.

  In the present modification, the protection function unit 36 operates in accordance with the temperature of the space between the building 10 and the housing 20. When the temperature sensor 44 is used instead of the protection function unit 36, the temperature sensor 44 detects the temperature of the space between the building 10 and the housing 20. The protection function portion 36 may be disposed on the installation surface 50 of the housing 20 or may be disposed on a support.

Third Embodiment
FIG. 10 shows the configuration of a fuel cell system according to Embodiment 3 of the present invention. In the fuel cell system 300, the shutoff valve 42 is closed when the temperature of the outer wall 12 of the building 10 exceeds the building threshold temperature. According to the present embodiment, the supply of hydrogen gas can be promptly stopped in response to external changes such as a fire of the building 10.

  In the fuel cell system 300, the protection function unit 36 is attached to the outer wall 12 of the building 10. According to such a configuration, the temperature of the outer wall 12 of the building 10 can be directly detected. Therefore, the change of the building 10 can be detected quickly.

  Also in the present embodiment, a temperature sensor 44 may be provided instead of the protective function unit 36 or together with the protective function unit 36. The temperature sensor 44 detects the temperature of the outer wall 12 of the building 10. The control unit 32 closes the shutoff valve when the temperature of the outer wall 12 of the building 10 detected by the temperature sensor 44 exceeds the building threshold temperature. Even when the temperature sensor 44 is used, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10.

  In the present embodiment, the outer wall 12 is an outer wall facing the housing 20 of the fuel cell system 300. However, the protective function portion 36 and / or the temperature sensor 44 may be attached to the outer wall not facing the housing 20. For example, if the building 10 has an area susceptible to fire, the protective function portion 36 and / or the temperature sensor 44 may be attached to the outer wall constituting the area.

Embodiment 4
FIG. 11 shows the configuration of a fuel cell system according to Embodiment 4 of the present invention. 10 shows a configuration of a fuel cell system according to Embodiment 4 of the present invention. In fuel cell system 400, housing 20 is in contact with building 10. The protection function unit 36 detects the temperature of the housing 20 at the contact position between the housing 20 and the building 10. In the present embodiment, the wall 21 of the housing 20 is in contact with the outer wall 12 of the building 10. At the contact position between the outer wall 12 and the wall portion 21, the protection function portion 36 is attached to the inner surface 21 p of the wall portion 21. When the temperature of the housing 20 exceeds the housing threshold temperature, the shutoff valve 42 is closed. According to the present embodiment, the supply of hydrogen gas can be promptly stopped in response to external changes such as a fire of the building 10. In particular, since the temperature of the housing 20 at the contact position between the building 10 and the housing 20 is detected, it is possible to more reliably detect an external change such as a fire of the building 10. As a result, the safety of the fuel cell system 400 is enhanced.

  In the present embodiment, the same effect can be obtained by using the temperature sensor 44 instead of the protection function unit 36.

(Modification 8)
FIG. 12 shows the configuration of a fuel cell system according to the eighth modification. The fuel cell system 402 according to the eighth modification is installed on the roof of the building 10. A casing 20 is in contact with the building 10 on the roof of the building 10. The protection function unit 36 detects the temperature of the housing 20 at the contact position between the housing 20 and the building 10. In the present modification, the wall 23 of the housing 20 is in contact with the outer wall 14 of the building 10. At the contact position between the outer wall 14 and the wall portion 23, the protection function portion 36 is attached to the inner surface 23 p of the wall portion 23 which is the bottom portion of the housing 20. When the temperature of the housing 20 exceeds the housing threshold temperature, the shutoff valve 42 is closed. According to this modification, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire of the building 10. In particular, since the temperature of the wall 23 of the housing 20 at the contact position between the building 10 and the housing 20 is detected, it is possible to more reliably detect any external change such as a fire of the building 10. As a result, the safety of the fuel cell system 402 is enhanced.

Fifth Embodiment
FIG. 13 shows the configuration of a fuel cell system according to Embodiment 5 of the present invention. 15 shows a configuration of a fuel cell system according to Embodiment 5 of the present invention. In the fuel cell system 500, the temperature sensor 44 is disposed inside the housing 20. The temperature sensor 44 detects the temperature of the housing 20, the temperature around the housing 20, or the temperature of the outer wall 12 of the building 10 from the inside of the housing 20. According to such a configuration, it is possible to reliably detect an external change while protecting the temperature sensor 44 from physical damage and the like. As a result, the reliability and safety of the fuel cell system 500 are also enhanced.

  In the present embodiment, the housing 20 is provided with an opening 21 r. The temperature sensor 44 may detect the temperature around the housing 20 and / or the temperature of the outer wall 12 of the building 10 through the opening 21 r. The opening 21 r may be provided with a cover capable of transmitting infrared light while preventing foreign matter from entering the inside of the housing 20. Such covers include glass plates and resin plates. The resin plate is made of, for example, a transparent resin such as acrylic. The thickness and material of the cover are determined so that the temperature around the housing 20 from the inside of the housing 20 and / or the temperature of the outer wall 12 of the building 10 can be accurately detected. The opening 21 r may be a simple through hole penetrating the wall 21.

  When the temperature sensor 44 detects the temperature of the housing 20 from the inside of the housing 20, the opening 21r is unnecessary. The temperature sensor 44 can detect the temperature of the inner surface 21 p of the wall 21 even if the temperature sensor 44 is provided in contact with the inner surface 21 p of the wall 21 or separated from the inner surface 21 p.

  Also in the present embodiment, the type of the temperature sensor 44 is not particularly limited. The temperature sensor 44 may be an infrared temperature sensor or a thermo viewer.

(Others)
The conditions under which the shutoff valve 42 is closed are not limited to one, and the shutoff valve 42 may be closed when a plurality of conditions are met. For example, the shutoff valve 42 may be closed when the temperature of the housing 20 exceeds the housing threshold temperature and the temperature around the housing 20 exceeds the ambient threshold temperature.

  As described above, in the fuel cell system according to the present invention, the supply of flammable gas such as hydrogen gas and city gas can be promptly stopped in response to an external abnormality such as a fire of the building 10.

DESCRIPTION OF SYMBOLS 10 buildings 12, 14 outer wall 20 housings 21, 22, 23, 24 walls 21p, 23p inner surface 21q, 22q outer surface 21r opening 30 fuel cell unit 30a fuel cell stack 30b reformer 30c peripheral equipment 32 control unit 34 power circuit 36 protection function unit 37, 38 power supply circuit 40 gas supply path 42 shutoff valve 44 temperature sensor 46 gas supply unit 47 gas supply pipe 48 fitting 50 installation surface 100, 102, 104, 106, 108, 200, 202, 204, 206 , 300, 400, 402,500 Fuel cell system

Claims (20)

A housing installed outside the building,
A fuel cell unit disposed inside the housing;
A gas supply path for supplying a flammable gas to the fuel cell unit;
A shutoff valve provided in the gas supply path;
Equipped with
If the temperature of the case exceeds the case threshold temperature, if the temperature around the case exceeds the ambient threshold temperature, and if the temperature of the outer wall of the building exceeds the building threshold temperature A fuel cell system, wherein the shutoff valve is closed in at least one case.   If the temperature of the case exceeds the case threshold temperature, if the temperature around the case exceeds the ambient threshold temperature, and if the temperature of the outer wall of the building exceeds the building threshold temperature The fuel cell system according to claim 1, further comprising a protection function operable to close the shutoff valve in at least one case.   The fuel cell system according to claim 2, wherein the protection function unit includes at least one selected from a thermal fuse and a thermo switch.   The fuel cell system according to claim 2, wherein the protection function unit is located on a power supply circuit connected to the shutoff valve. A control unit,
A temperature sensor for detecting the temperature of the housing;
And further
The fuel cell system according to claim 1, wherein the control unit closes the shutoff valve when the temperature of the housing detected by the temperature sensor exceeds the housing threshold temperature. A control unit,
A temperature sensor for detecting the temperature around the housing;
And further
The fuel cell system according to claim 1, wherein the control unit closes the shutoff valve when the ambient temperature of the casing detected by the temperature sensor exceeds the ambient threshold temperature. A control unit,
A temperature sensor for detecting the temperature of the outer wall of the building;
And further
The fuel cell system according to claim 1, wherein the control unit closes the shutoff valve when the temperature of the outer wall of the building detected by the temperature sensor exceeds the building threshold temperature.   The fuel cell system according to any one of claims 2 to 7, wherein the protective function unit or the temperature sensor is attached to an inner surface of the housing.   The fuel cell system according to claim 8, wherein the inner surface of the housing is an inner surface of a wall of the housing facing the building.   The temperature sensor is disposed inside the casing, and detects the temperature of the casing, the temperature around the casing, or the temperature of the outer wall of the building from the inside of the casing. The fuel cell system according to any one of Items 5 to 7.   The fuel cell system according to any one of claims 2 to 7, wherein the protective function unit or the temperature sensor is disposed outside the housing.   The fuel cell system according to any one of claims 2 to 7, wherein the protective function unit or the temperature sensor is attached to an outer surface of the housing.   The fuel cell system according to claim 12, wherein the outer surface of the housing is an outer surface of a wall of the housing facing the building.   The fuel cell system according to any one of claims 2 to 7, wherein the protective function unit or the temperature sensor is attached to the outer wall of the building. The housing is in contact with the building;
The fuel cell system according to any one of claims 2 to 5, wherein the protective function unit or the temperature sensor detects a temperature of the housing at a contact position between the housing and the building.   The fuel cell system according to any one of claims 1 to 15, wherein the shutoff valve is disposed inside the housing.   The fuel cell system according to any one of claims 1 to 15, wherein the shutoff valve is disposed outside the housing. The fuel cell unit includes a fuel cell stack,
The gas supply path is connected to the fuel cell stack,
The fuel cell system according to any one of claims 1 to 17, wherein hydrogen gas as the combustible gas is supplied to the fuel cell stack through the gas supply path. The fuel cell unit includes a fuel cell stack and a reformer,
The gas supply path is connected to the reformer,
A raw material gas as the flammable gas is supplied to the reformer through the gas supply path,
The fuel cell system according to any one of claims 1 to 17, wherein the reformer reacts the raw material gas with water to generate a hydrogen-containing gas to be supplied to the fuel cell stack.   The fuel cell system according to any one of claims 1 to 19, wherein the shutoff valve is a valve which is open when energized and closed when deenergized.

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