JPWO2012090964A1 - Fuel cell system - Google Patents

Abstract

A power generation unit including a cell stack that generates power using a hydrogen-containing gas, a control unit that adjusts the power generated by the power generation unit or controls the operation of the power generation unit, and a housing that houses at least the power generation unit and the control unit And an air flow path that circulates external air inside the housing and cools the inside of the housing, and a blower section that is provided in the air flow path and pumps air, and the air flow path is a control section. After cooling the air, air is circulated so as to cool the power generation unit.

Description

  The present invention relates to a fuel cell system.

  Conventionally, in a fuel cell system, a power generation unit including a cell stack that generates power using a hydrogen-containing gas and a control unit that adjusts the power generated by the power generation unit or controls the operation of the power generation unit are housed in a housing. Has been configured. In such a fuel cell system, for example, as described in Patent Document 1, a fan (air blowing unit) is installed in the casing, and the fan is operated to take outside air into the casing and ventilate. However, it is intended to cool devices such as a power generation unit and a control unit.

JP 2007-207441 A

  However, in the fuel cell system as described above, since the inside of the housing is uniformly ventilated and cooled by the fan, for example, it becomes difficult to efficiently cool the inside of the housing, and a fan having an excessive blowing capacity is required. There is a case. As a result, the economics of the system may be reduced.

  Then, this invention makes it a subject to provide the fuel cell system which can reduce the necessity of the ventilation part which has excess ventilation capability, and can improve the economical efficiency of a system.

  In order to solve the above problems, a fuel cell system according to one aspect of the present invention includes a power generation unit including a cell stack that generates power using a hydrogen-containing gas, and adjusts the power generated by the power generation unit, or A control unit that controls the operation, a housing that houses at least the power generation unit and the control unit, an air flow path that circulates external air in the housing and cools the inside of the housing, and an air flow path And an air flow path that pumps air, and the air flow path circulates the air so as to cool the power generation section after cooling the control section.

  In the fuel cell system of the present invention, the inside of the housing can be selectively and appropriately cooled by the air flow path, instead of being uniformly ventilated and cooled. That is, in the case of external air, the control unit that requires operation at a temperature lower than that of the power generation unit is first cooled, and then the power generation unit is cooled. Therefore, it is possible to efficiently cool the device in the housing, and it is possible to improve the economic efficiency of the system by reducing the necessity of a blowing unit having an excessive blowing capacity.

  In addition, an auxiliary device as a peripheral device for generating power in the power generation unit is provided, and the air flow path cools the control unit, the power generation unit and the auxiliary device in this order, or the control unit, the auxiliary device and the power generation unit. The air may be circulated so as to cool in this order.

  Further, air may be discharged to the outside on the downstream side of the air flow path. Further, the downstream side of the air flow path may supply air to the cell stack. In these cases, it is possible to suppress heat from being accumulated in the housing.

  Further, as a configuration that preferably exhibits the above-described effects, specifically, the control unit is housed in a box, and in the air flow path, air flows into the box from an inflow port formed in the box. In addition, there is a configuration in which air flows out of the box from an outlet formed in the box.

  In addition, the inside of the housing has a plurality of chambers provided for each of a plurality of devices, and the air flow path includes a plurality of chamber portions so as to cool the plurality of devices in the order of the lowest guaranteed operating temperature. Air may be circulated sequentially. Thereby, a some apparatus can be cooled selectively and in an appropriate order, and an apparatus can be cooled more efficiently in a housing | casing. As a result, it becomes possible to further reduce the necessity of a blower unit having an excessive blowing capacity.

  According to the present invention, it is possible to reduce the necessity of an air blowing unit having an excessive air blowing capacity and improve the economic efficiency of the system.

1 is a schematic block diagram showing a fuel cell system according to an embodiment. It is a schematic block diagram which shows the principal part of the fuel cell system which concerns on one Embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic block diagram showing a fuel cell system according to an embodiment of the present invention. As shown in FIG. 1, the fuel cell system 1 includes a desulfurization unit 2, a water vaporization unit 3, a hydrogen generation unit 4, a cell stack 5, an offgas combustion unit 6, a hydrogen-containing fuel supply unit 7, A supply unit 8, an oxidant supply unit 9, a power conditioner 10, and a control unit 11 are provided.

  The fuel cell system 1 generates power in the cell stack 5 using a hydrogen-containing fuel and an oxidant. The type of the cell stack 5 in the fuel cell system 1 is not particularly limited, and examples thereof include a polymer electrolyte fuel cell (PEFC), a solid oxide fuel cell (SOFC), and phosphoric acid. A type fuel cell (PAFC: Phosphoric Acid Fuel Cell), a molten carbonate type fuel cell (MCFC), and other types can be adopted. 1 may be appropriately omitted depending on the type of cell stack 5, the type of hydrogen-containing fuel, the reforming method, and the like.

  As the hydrogen-containing fuel, for example, a hydrocarbon fuel is used. As the hydrocarbon fuel, a compound containing carbon and hydrogen in the molecule (may contain other elements such as oxygen) or a mixture thereof is used. Examples of hydrocarbon fuels include hydrocarbons, alcohols, ethers, and biofuels. These hydrocarbon fuels are derived from conventional fossil fuels such as petroleum and coal, and synthetic systems such as synthesis gas. Those derived from fuel and those derived from biomass can be used as appropriate. Specific examples of hydrocarbons include methane, ethane, propane, butane, natural gas, LPG (liquefied petroleum gas), city gas, town gas, gasoline, naphtha, kerosene, and light oil. Examples of alcohols include methanol and ethanol. Examples of ethers include dimethyl ether. Examples of biofuels include biogas, bioethanol, biodiesel, and biojet.

  As the oxidizing agent, for example, air, pure oxygen gas (which may contain impurities that are difficult to remove by a normal removal method), or oxygen-enriched air is used.

  The desulfurization unit 2 performs desulfurization of the hydrogen-containing fuel supplied to the hydrogen generation unit 4. The desulfurization part 2 has a desulfurization catalyst for removing sulfur compounds contained in the hydrogen-containing fuel. As the desulfurization method of the desulfurization unit 2, for example, an adsorptive desulfurization method that adsorbs and removes sulfur compounds and a hydrodesulfurization method that removes sulfur compounds by reacting with hydrogen are employed. The desulfurization unit 2 supplies the desulfurized hydrogen-containing fuel to the hydrogen generation unit 4.

  The water vaporization unit (water vaporizer) 3 generates water vapor supplied to the hydrogen generation unit 4 by heating and vaporizing water. For the heating of the water in the water vaporization unit 3, for example, heat generated in the fuel cell system 1 such as recovering the heat of the hydrogen generation unit 4, the heat of the off-gas combustion unit 6, or the heat of the exhaust gas may be used. Moreover, you may heat water using other heat sources, such as a heater and a burner separately. In FIG. 1, only heat supplied from the off-gas combustion unit 6 to the hydrogen generation unit 4 is described as an example, but the present invention is not limited to this. The water vaporization unit 3 supplies the generated water vapor to the hydrogen generation unit 4.

  The hydrogen generation unit 4 generates a hydrogen rich gas (hydrogen-containing gas) using the hydrogen-containing fuel from the desulfurization unit 2. The hydrogen generator 4 has a reformer that reforms the hydrogen-containing fuel with a reforming catalyst. The reforming method in the hydrogen generating unit 4 is not particularly limited, and for example, steam reforming, partial oxidation reforming, autothermal reforming, and other reforming methods can be employed. The hydrogen generator 4 may have a configuration for adjusting the properties in addition to the reformer reformed by the reforming catalyst depending on the properties of the hydrogen rich gas required for the cell stack 5. For example, when the type of the cell stack 5 is a polymer electrolyte fuel cell (PEFC) or a phosphoric acid fuel cell (PAFC), the hydrogen generation unit 4 is configured to remove carbon monoxide in the hydrogen-rich gas. (For example, a shift reaction part and a selective oxidation reaction part). The hydrogen generation unit 4 supplies a hydrogen rich gas to the anode 12 of the cell stack 5.

  The cell stack 5 generates power using the hydrogen rich gas from the hydrogen generation unit 4 and the oxidant from the oxidant supply unit 9. The cell stack 5 includes an anode 12 to which a hydrogen-rich gas is supplied, a cathode 13 to which an oxidant is supplied, and an electrolyte 14 disposed between the anode 12 and the cathode 13. The cell stack 5 supplies power to the outside via the power conditioner 10. The cell stack 5 supplies the hydrogen rich gas and the oxidant, which have not been used for power generation, to the off gas combustion unit 6 as off gas. Note that a combustion section (for example, a combustor that heats the reformer) provided in the hydrogen generation section 4 may be shared with the off-gas combustion section 6.

  The off gas combustion unit 6 burns off gas supplied from the cell stack 5. The heat generated by the off-gas combustion unit 6 is supplied to the hydrogen generation unit 4 and used for generation of a hydrogen rich gas in the hydrogen generation unit 4.

  The hydrogen-containing fuel supply unit 7 supplies hydrogen-containing fuel to the desulfurization unit 2. The water supply unit 8 supplies water to the water vaporization unit 3. The oxidant supply unit 9 supplies an oxidant to the cathode 13 of the cell stack 5. The hydrogen-containing fuel supply unit 7, the water supply unit 8, and the oxidant supply unit 9 are configured by a pump, for example, and are driven based on a control signal from the control unit 11.

  The power conditioner 10 adjusts the power from the cell stack 5 according to the external power usage state. For example, the power conditioner 10 performs a process of converting a voltage and a process of converting DC power into AC power.

  The control unit 11 performs control processing for the entire fuel cell system 1. The control unit 11 is configured by, for example, a device including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an input / output interface. The control unit 11 is electrically connected to a hydrogen-containing fuel supply unit 7, a water supply unit 8, an oxidant supply unit 9, a power conditioner 10, and other sensors and auxiliary equipment not shown. The control unit 11 acquires various signals generated in the fuel cell system 1 and outputs a control signal to each device in the fuel cell system 1.

  FIG. 2 is a schematic block diagram showing the main part of the fuel cell system according to one embodiment of the present invention. As shown in FIG. 2, the fuel cell system 1 includes a power generation unit 21, the power conditioner 10, and an auxiliary machine module 22, which are hermetically accommodated so as to be installed in a housing 23. Yes.

  The power generation unit 21 is a module that generates power, and includes the desulfurization unit 2, the water vaporization unit 3, the hydrogen generation unit 4, the cell stack 5, the offgas combustion unit 6, the hydrogen-containing fuel supply unit 7, and the water At least a supply unit 8 and the oxidant supply unit 9 are provided. The power generation unit 21 is accommodated in a box (chamber) 21a and modularized.

  As described above, the power conditioner 10 adjusts the power generated by the cell stack 5 of the power generation unit 21. The power conditioner 10 has a control base as the control unit 11 that controls the operation of the power generation unit 21. The power conditioner 10 is housed in a box (chamber) 10a and modularized, like the power generation unit 21. The auxiliary machine module 22 is a peripheral device for generating power in the power generation unit. Similar to the power generation unit 21 and the power conditioner 10, the accessory module 22 is housed in a box (chamber) 22a and modularized.

  In addition, the fuel cell system 1 includes an air flow path 25 and a cathode blower (blower unit) 26. The air flow path 25 circulates external air inside the housing 23 to cool the inside of the housing 23. The cathode blower 26 is provided in the air flow path 25, and air is sent to the cathode 13 (see FIG. 1) of the cell stack 5 in the power generation unit 21 through the air flow path 25 to blow air.

  Here, the air flow path 25 of this embodiment distribute | circulates air so that the power conditioner 10, the electric power generation part 21, and the auxiliary machine module 22 may be cooled in this order in the housing | casing 23. FIG. Specifically, as shown below, air is sequentially circulated through the plurality of boxes 10a, 21a, and 22a so that the plurality of modules (devices) are cooled in the order of the lowest guaranteed operating temperature.

  That is, in the air flow path 25, first, external air (outdoor air) taken into the housing 23 through the flue pipe (air pipe) T by the operation of the cathode blower 26 passes through the power conditioner 10. The power conditioner 10 is cooled by flowing into the power conditioner 10 from the inlet of the box 10a to be accommodated. And the said air flows out out of the power conditioner 10 from the outflow port of the box 10a.

  Subsequently, the air after cooling the power conditioner 10 flows into the power generation unit 21 from the inlet of the box body 21 a that houses the power generation unit 21, and the power generation unit 21 is cooled. And the said air flows out out of the electric power generation part 21 from the outflow port of the box 21a.

  Subsequently, the air after cooling the power generation unit 21 flows into the auxiliary module 22 from the inlet of the box 22a that houses the auxiliary module 22, and the auxiliary module 22 is cooled. And the said air flows out out of the auxiliary equipment module 22 from the outflow port of the box 22a. Finally, the air after cooling the accessory module 22 is supplied to the cathode 13 (see FIG. 1) of the cell stack 5 via the cathode blower 26. That is, air whose temperature has been increased by cooling a plurality of modules is supplied to the cathode 13 of the cell stack 5 from the downstream side of the air flow path 25.

  As described above, in the present embodiment, the cathode blower 26 is provided on the air flow path 25 on the downstream side of the auxiliary equipment module 22 and on the upstream side of the power generation unit 21, but is not limited thereto. What is necessary is just to be provided in the air flow path 25. FIG. Moreover, it may replace with the cathode blower 26 and may be provided with another ventilation part. In this case, the downstream side of the air flow path 25 may communicate with the outside of the housing 23 and the air may be discharged to the outside on the downstream side.

  As described above, in the fuel cell system 1 of the present embodiment, the inside of the casing 23 is selectively cooled in the proper order by the air flow path 25 instead of uniformly ventilating and cooling the inside of the casing 23. it can. That is, the air introduced from the outside first cools the power conditioner 10 that needs to operate at a lower temperature than the power generation unit 21 and the accessory module 22 in the housing 23, and then, the power generation unit 21. And the auxiliary machine module 22 is cooled.

  Therefore, according to the present embodiment, the power conditioner 10, the power generation unit 21, and the auxiliary module 22 can be efficiently cooled in the housing 23. As a result, it is possible to reduce the necessity of the cathode blower 26 having an excessive blowing capacity and improve the economic efficiency of the system. Furthermore, since the cathode blower 26 having an excessive blowing capacity is not required in this way, it is possible to suppress excessive power consumption and noise of the cathode blower 26.

  Moreover, in this embodiment, since air is supplied to the cell stack 5 on the downstream side of the air flow path 25 as described above, it is possible to suppress heat from being accumulated in the housing 23. Furthermore, in this case, it is possible to supply the cell stack 5 with air whose temperature has been increased by cooling the inside of the housing 23.

  In the present embodiment, as described above, a plurality of modules (the power conditioner 10, the power generation unit 21, and the auxiliary machine module 22) are provided in the casing 23 by the box bodies 10a, 21a, and 22a. And the air flow path 25 distribute | circulates air sequentially to these boxes 10a, 21a, and 22a so that it may cool in order with low operation | movement guarantee temperature. Thereby, the inside of the housing | casing 23 can be cooled suitably in a more appropriate order, and a some module can be cooled more efficiently in the housing | casing 23. FIG. As a result, it becomes possible to further reduce the necessity of the cathode blower 26 having an excessive blowing capacity.

  Moreover, in this embodiment, it can suppress that the pressure loss more than necessary in the air flow path 25 generate | occur | produces. Furthermore, each module can be cooled according to the temperature required by each module.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. The present invention is modified without departing from the scope described in the claims or applied to others. It may be.

  For example, although the air flow path 25 of the said embodiment distribute | circulates air so that the power conditioner 10, the electric power generation part 21, and the auxiliary machine module 22 may be cooled in this order, the power conditioner 10, the auxiliary machine module 22, and the electric power generation part 21 are circulated. In some cases, air is circulated so as to cool in this order.

  Moreover, in the said embodiment, although the air flow path 25 distribute | circulates air in a module, this air flow path 25 is air so that it may contact the outer surface (outer wall of box 10a, 21a, 22a) of a module. May be circulated, thereby cooling the module (cooling the outer surface). Moreover, in the said embodiment, although outdoor air is distribute | circulated in the housing | casing 23 through the flue pipe T, when indoor air is distribute | circulated in the housing | casing 23 as external air, the flue pipe T Is no longer necessary. In the above description, the “module” means, for example, one in which one or a plurality of elements (parts or devices) are aggregated in terms of function or configuration as a function for realizing a predetermined function.

  In the above embodiment, a gas that does not require reforming, such as pure hydrogen or a hydrogen-enriched gas, can be supplied as the hydrogen-containing fuel. In this case, the reformer which the hydrogen generating part 4 has becomes unnecessary.

  According to the present invention, it is possible to reduce the necessity of an air blowing unit having an excessive air blowing capacity and improve the economic efficiency of the system.

  DESCRIPTION OF SYMBOLS 1 ... Fuel cell system, 5 ... Cell stack, 10 ... Power conditioner (control part, apparatus), 10a, 21a, 22a ... Box (chamber part), 11 ... Control part, 21 ... Power generation part (equipment), 22 ... Auxiliary equipment modules (auxiliary equipment, equipment), 23... Casing, 25... Air flow path, 26.

Claims (6)

A power generation unit including a cell stack that generates power using a hydrogen-containing gas;
A controller that adjusts the power generated by the power generation unit or controls the operation of the power generation unit;
A housing that houses at least the power generation unit and the control unit;
An air flow path for circulating outside air in the housing and cooling the housing;
A blower section provided in the air flow path and pumping the air,
The fuel cell system in which the air flow channel distributes the air so as to cool the power generation unit after cooling the control unit. An auxiliary machine as a peripheral device for generating power in the power generation unit,
The air flow path is configured to cool the control unit, the power generation unit, and the auxiliary machine in this order, or to cool the control unit, the auxiliary machine, and the power generation unit in this order. The fuel cell system according to claim 1, wherein the fuel cell system is distributed.   The fuel cell system according to claim 1, wherein the air is discharged to the outside on the downstream side of the air flow path.   The fuel cell system according to claim 1 or 2, wherein a downstream side of the air flow path supplies the air to the cell stack. The control unit is accommodated in a box,
In the air flow path, the air flows into the box from an inlet formed in the box, and the air flows out of the box from an outlet formed in the box. Item 5. The fuel cell system according to any one of Items 1 to 4. The inside of the housing has a plurality of chambers provided for each of a plurality of devices,
The fuel cell according to any one of claims 1 to 5, wherein the air flow passage sequentially circulates the air through the plurality of chamber portions so as to cool the plurality of devices in order of decreasing operation guarantee temperature. system.

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