JP6945163B2 - Fuel cell system - Google Patents

Description

The present invention relates to a fuel cell system.

Conventionally, this type of fuel cell system may be provided with a thermal fuse in order to prevent a fire from occurring due to leakage of flammable gas, abnormal heating of a heater, or the like (for example, Patent Document 1). The thermal fuse is provided in the system and blows when the temperature in the system exceeds the permissible range. The fuel shutoff valve is closed when the thermal fuse is blown.

Japanese Unexamined Patent Publication No. 2014-26873

However, in the conventional configuration, only a thermal fuse is provided in the system. Therefore, the conventional configuration has a problem that it is not possible to promptly detect an external abnormality such as a fire in a building and it is not possible to sufficiently secure safety.

The present invention solves the above-mentioned conventional problems, and an object of the present invention 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 used.
The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
With
It is selected from the cases where the temperature of the housing exceeds the housing threshold temperature, 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 case.

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

Configuration diagram of the fuel cell system according to the first embodiment of the present invention Configuration diagram of the fuel cell system according to the first modification Configuration diagram of the fuel cell system according to the second modification Configuration diagram of the fuel cell system according to the modified example 3 Configuration diagram of the fuel cell system according to the modified example 4 Configuration diagram of the fuel cell system according to the second embodiment of the present invention Configuration diagram of the fuel cell system according to the modified example 5 Configuration diagram of the fuel cell system according to the modified example 6 Configuration diagram of the fuel cell system according to the modified example 7 Configuration diagram of the fuel cell system according to the third embodiment of the present invention Configuration diagram of the fuel cell system according to the fourth embodiment of the present invention Configuration diagram of the fuel cell system according to the modified example 8 Configuration diagram of the fuel cell system according to the fifth embodiment of the present invention

The first invention comprises a housing installed outside the building, a fuel cell unit arranged inside the housing, a gas supply path for supplying flammable gas to the fuel cell unit, and the above. In a fuel cell system including a shutoff valve provided in a gas supply path, when the temperature of the housing exceeds the housing threshold temperature, the temperature around the housing exceeds the ambient threshold temperature. The shutoff valve is closed if, and at least one selected from the case where the temperature of the outer wall of the building exceeds the building threshold temperature. 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 when the temperature of the outer wall of the building exceeds the building threshold temperature. The shutoff valve is closed in at least one case selected from the above cases. The supply of flammable gas can be stopped promptly in response to an external incident such as a building fire. Therefore, according to the first invention, it is possible to provide a fuel cell system having high safety.

In the second invention, in particular, in the fuel cell system of 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 protective function unit that operates to close the shutoff valve may be provided when at least one case 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 flammable gas can be promptly stopped in response to an external incident such as a fire in the building.

In the third invention, in particular, the protective function portion of the second invention may include at least one selected from a thermal fuse and a thermoswitch. Thermal fuses and thermoswitches are devices that do not require power and control and are highly reliable. Therefore, these devices can be used to reliably close the shutoff valve in the event of an external event such as a building fire.

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

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

In the sixth invention, in particular, the fuel cell system of the first invention may further include a control unit and a temperature sensor for detecting the ambient temperature of the housing, and the control unit may further include 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 invention, the supply of flammable gas can be promptly stopped in response to an external accident such as a fire in a building.

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

In the eighth invention, in particular, the protective function unit 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 an external abnormality while protecting the protective function unit from physical damage and the like.

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

In the tenth invention, in particular, the temperature sensor of any one of the fifth to seventh inventions is arranged inside the housing, and the temperature of the housing is changed from the inside of the housing to the temperature of the housing. The temperature of the surroundings 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 abnormality while protecting the temperature sensor from physical damage and the like. As a result, the reliability and safety of the fuel cell system are also increased.

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

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

In the thirteenth invention, in particular, the outer surface of the housing of the twelfth invention may be the outer surface of the wall portion of the housing facing the building. According to the thirteenth invention, the supply of the flammable gas can be quickly stopped in response 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 unit or the temperature sensor of any one of the second to seventh inventions may be attached to the outer wall of the building. With such a configuration, the temperature of the outer wall of the building can be directly detected. Therefore, it is possible to detect a change in the building as soon as possible.

In the fifteenth invention, in particular, the housing of any one of the second to fifth inventions may be in contact with the building, and the protective function unit or the temperature sensor is the housing and the housing. The temperature of the housing may be detected at the contact position with the 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 in the building. As a result, the safety of the fuel cell system is increased.

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

In the eighteenth invention, in particular, the fuel cell unit of any one of the first to the 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. The pure hydrogen fuel cell system does not require a reformer, which is advantageous for miniaturization. In addition, the pure hydrogen fuel cell system can achieve high power generation efficiency and can be started quickly. By using hydrogen gas derived from renewable energy, a completely CO _2- free system can be constructed.

In the nineteenth invention, in particular, the fuel cell unit of any one of the first to seventeenth inventions may include a fuel cell stack and a reformer, and the gas supply path is the said. It may be connected to the reformer, or the raw material gas as the flammable gas may be supplied to the reformer through the gas supply path, and the reformer reacts the raw material gas with water. It may be allowed to generate a hydrogen-containing gas to be supplied to the fuel cell stack. Since the fuel cell system of the nineteenth invention does not require a hydrogen gas source such as a hydrogen storage tank, it can be easily introduced into a small-scale facility such as a house or an apartment house.

In the twentieth invention, in particular, the shutoff valve of any one of the first to nineteenth inventions may be a valve that is opened when energized and closed when not energized. 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 to the present embodiment.

(Embodiment 1)
FIG. 1 shows the configuration of the fuel cell system according to the first embodiment 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. An appropriate amount of space is secured between the building 10 and the housing 20. The fuel cell unit 30 is arranged inside the housing 20. The gas supply path 40 is connected to the fuel cell unit 30 and extends to the outside of the housing 20. A shutoff valve 42 is provided in the gas supply path 40. The shutoff valve 42 is located inside the housing 20. 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 uses the fuel gas and the oxidant gas to generate electric power. In this embodiment, the hydrogen gas is the fuel gas and the air is the oxidant gas. The fuel cell stack 30a may be a solid polymer type or a solid oxide type. Examples of peripheral devices 30c include pumps, valves, heat exchangers, heaters and sensors. The gas supply path 40 is connected to the fuel cell stack 30a. 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 other equipment such as a desulfurizer. The pure hydrogen fuel cell system does not require a reformer, which is advantageous for miniaturization. In addition, the pure hydrogen fuel cell system can achieve high power generation efficiency and can be started quickly. By using hydrogen gas derived from renewable energy, a completely CO _2- free system can be constructed.

The electric power generated in the fuel cell system 100 may be supplied to the building 10 or may be supplied to other equipment such as commercial power transmission equipment. The type of the building 10 is not particularly limited. Examples of building 10 include houses, apartments, commercial facilities, public facilities, accommodation facilities, office buildings, multi-tenant 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 arranged inside the housing 20. The control unit 32 may be arranged outside the housing 20. The power supply circuit 34 may be arranged outside the housing 20.

The control unit 32 controls the control target 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 properly operating the fuel cell system 100. The power supply circuit 34 plays a role of supplying the electric power generated in the fuel cell stack 30a to the external device and the peripheral device 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 this embodiment, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire in 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 wall portion 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 so as 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 event such as a fire in the building 10.

In this embodiment, the protective 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 are highly reliable. Therefore, if these devices are used, the shutoff valve 42 can be reliably closed in response to an external event such as a fire in the building 10.

A thermal fuse is a device provided with a fusible material that blows as the temperature rises. Solubles are made of, for example, low melting point metals and resins. The thermoswitch may be a switch using a bimetal (so-called bimetal thermostat) or a switch using a PTC thermistor (Positive Temperature Coefficient Thermistor). A switch using a bimetal is a device that utilizes the displacement of the bimetal by heat. A switch using a PTC thermistor is a device that utilizes the characteristics of a PTC thermistor whose resistance rises sharply 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. Thermoswitches have the advantage of simplifying maintenance. Thermal fuses are advantageous in that they can ensure high reliability and high safety.

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 opens, 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, it is not necessary to exchange signals with other circuits such as the control unit 32, so that the shutoff valve 42 can be reliably closed in an emergency.

However, it is not essential that the protection function unit 36 is located on the power supply circuit 37. For example, the protection function unit 36 may form 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 has operated at the set temperature, the control unit 32 may execute an electrical process for closing the shutoff valve 42.

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

In the present embodiment, the housing 20 is composed of a plurality of wall portions 21 to 24. The wall portion 21 is a portion facing the building 10. The wall portion 22 is the ceiling portion of the housing 20. The wall portion 23 is the bottom portion of the housing 20. The wall portion 24 is a portion facing the wall portion 21. In the present embodiment, the protective function portion 36 is attached to the inner surface 21p of the wall portion 21. The wall portion 21 is the closest portion to the building 10, and if a fire breaks out in the building 10, it 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 quickly stopped in response to the temperature rise. As a result, the safety of the fuel cell system 100 can be further enhanced.

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

According to this 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 and the position of the protective function unit 36. 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 opened when energized and closed when not energized. This type of valve is excellent in terms of safety. Further, this type of valve is excellent in compatibility with the protective function unit 36. The shutoff valve 42 is typically a solenoid valve. Power is supplied to the shutoff valve 42 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 arranged 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. The same reference numerals may be given to common elements between the fuel cell system 100 of the first embodiment and other fuel cell systems, and the description thereof may be omitted. The description of each embodiment and each modification may be applied to each other as long as there is no technical conflict. The embodiments and variations may be combined with each other as long as they are not technically inconsistent.

(Modification example 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 including the reformer 30b. 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 30b. Through the gas supply path 40, a raw material gas as a flammable gas is supplied to the reformer 30b from a raw material gas source (not shown) such as an urban gas infrastructure. The reformer 30b reacts the raw material gas with water to generate a hydrogen-containing gas to be supplied to the fuel cell stack 30a. The raw material gas is, for example, a hydrocarbon gas such as methane gas or propane gas. Also in this modified example, the supply of the raw material gas can be promptly stopped in response to an external change such as a fire in the building 10. Since the fuel cell system 102 of this modification does not require a hydrogen gas source such as a hydrogen storage tank, it can be easily introduced into a small-scale facility such as a house or an apartment house.

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

(Modification 2)
FIG. 3 shows the configuration of the fuel cell system according to the 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 instead of the protection function unit 36. The temperature sensor 44 is attached to the inner surface 21p of the housing 20. The temperature sensor 44 is electrically connected to the control unit 32. The 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 event such as a fire in the building 10.

The type of the temperature sensor 44 is not particularly limited. The temperature sensor 44 may be a contact type sensor or a non-contact type sensor. Examples of contact sensors include temperature sensors using thermistors and temperature sensors using thermocouples. Examples of non-contact sensors include infrared temperature sensors and thermoviewers.

A protective function unit 36 may be provided together with the temperature sensor 44. 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 so as to close the shutoff valve 42 when the temperature of the housing 20 exceeds the second housing threshold temperature. The second housing threshold temperature can be set to a temperature higher than the first housing threshold temperature. In this case, the protection function unit 36 functions as a final safety device that complements the temperature sensor 44, so that 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 may be applied to other embodiments and other modifications.

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

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

(Modification example 4)
FIG. 5 shows the configuration of the fuel cell system according to the modified example 4. In the fuel cell system 108 according to the fourth modification, the shutoff valve 42 may be a valve that operates 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. 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 on, for example, the power supply circuit 38 connected to the gas supply device 46. When the protection function unit 36 operates, the power supply circuit 38 opens, the power supply to the gas supply device 46 is stopped, the supply of control gas from the gas supply device 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 device 46 becomes insufficient, the gas supply device 46 stops, the supply of control gas from the gas supply device 46 to the shutoff valve 42 stops, and the shutoff valve 42 Is closed. According to such a configuration, it is not necessary to exchange signals with other circuits such as the control unit 32, so that the shutoff valve 42 can be reliably closed in an emergency.

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

(Embodiment 2)
FIG. 6 shows the configuration of the fuel cell system according to the second embodiment of the present invention. In the fuel cell system 200, the protection function unit 36 is arranged outside the housing 20. With such a configuration, it is possible to directly and surely detect an external abnormality such as a fire in the building 10. The housing 20 is fixed to the building 10 by a plurality of metal fittings 48. The metal fitting 48 may be a part of the housing 20. The configuration and function of the protective function unit 36 are as described in the first embodiment. Only one metal fitting 48 may be provided.

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

When the protection function unit 36 detects the temperature of the housing 20, the protection function unit 36 operates when the temperature of the housing 20 exceeds the housing threshold temperature. As a result, the shutoff valve 42 is closed. When the protective function unit 36 detects the ambient temperature of the housing 20, the protective function unit 36 operates when the ambient temperature of the housing 20 exceeds the ambient threshold temperature. As a result, 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 an external change such as a fire in 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 ambient temperature of 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 and the position of the protective function unit 36. In one example, the ambient threshold temperature is a temperature set in the range of 100-120 ° C. The "periphery of the housing 20" may be an area within 5 m from the housing 20 or an area within 3 m. The ambient temperature of the housing 20 can be the temperature measured in such an area (space or ground). By setting such a region, it is possible to reliably detect a temperature rise due to heat radiation from the building 10 or a flame extending from the building 10 to the outside.

In the present embodiment, the protective function portion 36 is attached to the outer surface 21q of the wall portion 21 of the housing 20. The outer surface 21q is the outer surface of the wall portion 21 of the housing 20 facing the building 10. The wall portion 21 is the closest portion to the building 10, and if a fire breaks out in the building 10, it 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 quickly stopped in response to the temperature rise. As a result, the safety of the fuel cell system 200 can be further enhanced.

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

(Modification 5)
FIG. 7 shows the configuration of the fuel cell system according to the modified example 5. The fuel cell system 202 according to the modified example 5 includes a temperature sensor 44 instead of the protection function unit 36. The temperature sensor 44 is attached to, for example, the outer surface 21q of the housing 20. The temperature sensor 44 is electrically connected to the control unit 32, and the 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 portion 21 of the housing 20, may detect the temperature around the housing 20, and detect the temperature of the outer wall of the building 10. It may be a thing. In the control unit 32, when the temperature of the housing 20 exceeds the housing threshold temperature, when the ambient temperature of the housing 20 exceeds the ambient threshold temperature, or when the temperature of the outer wall 12 of the building 10 exceeds the building threshold temperature. When the temperature 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 event such as a fire in 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 protective 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 modified example 2. 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. It is also possible to use a flame sensor instead of the temperature sensor 44 or together with the temperature sensor 44. The flame sensor may be a sensor that detects weak light of a specific wavelength contained in the flame, and recognizes the existence of the flame by analyzing the spectral pattern of infrared rays contained in the light emitted from the flame. It may be a sensor. The shutoff valve 42 may be closed when the presence of flame is found around the housing 20.

A protection function unit 36 may be provided in place of the temperature sensor 44 or together with the temperature sensor 44.

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

(Modification 6)
FIG. 8 shows the configuration of the fuel cell system according to the modified example 6. In the fuel cell system 204 according to the modification 6, the protective function portion 36 is attached to the outer surface 22q of the wall portion 22 of the housing 20. The wall portion 22 is a wall portion that does not face the building 10. In this modification, the wall portion 22 is the ceiling portion of the housing 20. For example, if a fire breaks out in the building 10, there is a high possibility that not only the wall portion 21 facing the building 10 but the entire housing 20 will be heated. From this point of view, the wall portion to which the protective function portion 36 should be attached is not limited to the wall portion 21 facing the building 10.

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

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

(Modification 7)
FIG. 9 shows the configuration of the fuel cell system according to the modified example 7. In the fuel cell system 206 according to the modification 7, the protective function unit 36 is arranged in the space between the building 10 and the housing 20. When the ambient temperature of 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 event such as a fire in the building 10.

In this modification, the protective function unit 36 operates according to 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 protective function unit 36 may be arranged on the installation surface 50 of the housing 20 or may be arranged on the support.

(Embodiment 3)
FIG. 10 shows the configuration of the fuel cell system according to the third embodiment 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 this embodiment, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire in the building 10.

In the fuel cell system 300, the protective 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, it is possible to quickly detect an abnormality in the building 10.

Also in this embodiment, the temperature sensor 44 may be provided in place of the protection function unit 36 or together with the protection 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 in 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 unit 36 and / or the temperature sensor 44 may be attached to the outer wall that does not face the housing 20. For example, when the building 10 has an area that is likely to be a source of fire, the protective function unit 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 the fuel cell system according to the fourth embodiment of the present invention. The configuration of the fuel cell system according to the fourth embodiment of the present invention is shown. In the fuel cell system 400, the housing 20 is in contact with 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 embodiment, the wall portion 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 protective function portion 36 is attached to the inner surface 21p 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 this embodiment, the supply of hydrogen gas can be promptly stopped in response to an external change such as a fire in 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 in the building 10. As a result, the safety of the fuel cell system 400 is increased.

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 the fuel cell system according to the modified example 8. The fuel cell system 402 according to the modified example 8 is installed on the roof of the building 10. On the roof of the building 10, the housing 20 is in contact with 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 this modification, the wall portion 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 protective function portion 36 is attached to the inner surface 23p 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 event such as a fire in the building 10. In particular, since the temperature of the wall portion 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 an external change such as a fire in the building 10. As a result, the safety of the fuel cell system 402 is increased.

(Embodiment 5)
FIG. 13 shows the configuration of the fuel cell system according to the fifth embodiment of the present invention. The configuration of the fuel cell system according to the fifth embodiment of the present invention is shown. In the fuel cell system 500, the temperature sensor 44 is arranged 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 abnormality 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 21r. The temperature sensor 44 can detect the temperature around the housing 20 and / or the temperature of the outer wall 12 of the building 10 through the opening 21r. The opening 21r may be provided with a cover capable of transmitting infrared rays while preventing foreign matter from entering the inside of the housing 20. Examples of such a cover include a glass plate and a resin plate. The resin plate is made of a transparent resin such as acrylic. The thickness and material of the cover are determined so that the temperature around the housing 20 and / or the temperature of the outer wall 12 of the building 10 can be accurately detected from the inside of the housing 20. The opening 21r may be a mere 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 21p of the wall portion 21, regardless of whether the wall portion 21 is provided in contact with the inner surface 21p or away from the inner surface 21p.

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

(others)
The condition for closing the shutoff valve 42 is not limited to one, and the shutoff valve 42 may be closed when a plurality of conditions are satisfied. For example, the shutoff valve 42 may be closed when the temperature of the housing 20 exceeds the housing threshold temperature and the ambient temperature of the housing 20 exceeds the ambient threshold temperature.

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

10 Building 12, 14 Outer wall 20 Housing 21, 22, 23, 24 Wall 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 supply circuit 36 Protective function unit 37, 38 Power supply circuit 40 Gas supply path 42 Shutoff valve 44 Temperature sensor 46 Gas supply 47 Gas supply pipe 48 Bracket 50 Installation surface 100, 102, 104, 106, 108, 200, 202, 204, 206 , 300, 400, 402,500 Fuel cell system

Claims (13)

The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
A protective function unit that operates to close the shutoff valve when the temperature of the housing exceeds the threshold temperature of the housing.
With
The protective function unit is attached to the inner surface of the housing.
The inner surface of the housing is the inner surface of a wall portion facing the building.
The wall portion is a fuel cell system that is the closest portion to the building. The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
Protection that operates to close the shutoff valve when at least one selected from the case where the temperature of the housing exceeds the housing threshold temperature and the case where the temperature around the housing exceeds the ambient threshold temperature. Functional part and
With
The protective function unit is attached to the outer surface of the housing, and is attached to the outer surface of the housing.
The outer surface of the housing is the outer surface of a wall portion facing the building.
The wall portion is a fuel cell system that is the closest portion to the building. The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
A protective function unit that operates to close the shutoff valve when the temperature of the outer wall of the building exceeds the building threshold temperature.
With
The protective function unit is a fuel cell system attached to the outer wall of the building. The fuel cell system according to any one of claims 1 to 3, wherein the protective function unit includes at least one selected from a thermal fuse and a thermo switch. The fuel cell system according to any one of claims 1 to 4, wherein the protection function unit is located on a power supply circuit connected to the shutoff valve. The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
Control unit and
A temperature sensor that detects the temperature of the housing and
With
The control unit closes the shutoff valve when the temperature of the housing detected by the temperature sensor exceeds the housing threshold temperature.
The temperature sensor is attached to the inner surface of the housing and is mounted on the inner surface of the housing.
The inner surface of the housing is the inner surface of a wall portion facing the building.
The wall portion is a fuel cell system that is the closest portion to the building. The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
Control unit and
A temperature sensor that detects the temperature around the housing and
With
The control unit closes the shutoff valve when the ambient temperature of the housing detected by the temperature sensor exceeds the ambient threshold temperature.
The temperature sensor is attached to the outer surface of the housing, and the temperature sensor is attached to the outer surface of the housing.
The outer surface of the housing is the outer surface of a wall portion facing the building.
The wall portion is a fuel cell system that is the closest portion to the building. The housing installed outside the building and
The fuel cell unit arranged inside the housing and
A gas supply path for supplying flammable gas to the fuel cell unit and
A shutoff valve provided in the gas supply path and
Control unit and
A temperature sensor that detects the temperature of the outer wall of the building,
With
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 temperature sensor is a fuel cell system mounted on the outer wall of the building. The fuel cell system according to any one of claims 1 to 8 , wherein the shutoff valve is arranged inside the housing. The fuel cell system according to any one of claims 1 to 8 , wherein the shutoff valve is arranged outside the housing. The fuel cell unit includes a fuel cell stack.
The gas supply path is connected to the fuel cell stack and
The fuel cell system according to any one of claims 1 to 10 , wherein hydrogen gas as the flammable 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 and
The raw material gas as the flammable gas is supplied to the reformer through the gas supply path, and the reformer is supplied with the raw material gas as the flammable gas.
The fuel cell system according to any one of claims 1 to 10 , 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 12 , wherein the shutoff valve is a valve that is opened when energized and closed when not energized.

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