JP2015141825A - fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell system capable of continuing power generation even if power generation of some of a plurality of power generation systems is disabled, or power generation amount is reduced.SOLUTION: A fuel cell system includes a plurality of power generation systems 1 each including a reformer 3 for reforming raw fuel gas, a raw fuel pump 35 for supplying raw fuel gas to the reformer 3, a water pump 12 for supplying water to the reformer 3, a stack 5 supplied with the reformed gas produced by the reformer 3, a blower 37 for supplying air to th stack 5, and an on-off valve 41 for opening and closing the raw fuel gas supply path to the reformer 3, one upstream side raw fuel supply path 45 for supplying raw fuel gas to the supply paths of the plurality of power generation systems 1, respectively, and a controller 7 for controlling the on-off valves 41 only of some of the plurality of power generation systems 1 to close, when power generation of some of the plurality of power generation systems 1 is disabled, or power generation amount of some power generation systems 1 is reduced.

Description

  The present invention relates to a fuel cell system including a plurality of power generation systems.

  In recent years, various fuel cell devices have been proposed as next-generation energy. As such a fuel cell device, a fuel cell module and an auxiliary machine for operating the fuel cell module are housed in an outer case. (See, for example, Patent Document 1).

  In this fuel cell device, the interior of the exterior case is partitioned up and down by a partition plate, the fuel cell module is accommodated on the upper side, and auxiliary equipment for operating the fuel cell module is accommodated on the lower side. ing. Auxiliary equipment includes a blower for supplying air, a raw fuel pump for supplying raw fuel, a desulfurizer, a water pump for supplying water to the reformer, etc., and a control device for controlling these auxiliary equipments. It has.

  The fuel cell module is configured by housing a stack device in which a plurality of fuel cells are electrically connected in series in a storage container.

JP 2012-138185 A

  However, the conventional fuel cell system is a single power generation system in which one set of auxiliary equipment for supplying raw fuel or the like to one fuel cell module is housed. If one auxiliary equipment fails, power generation becomes impossible. The entire fuel cell system had to be stopped.

  An object of the present invention is to provide a fuel cell system capable of continuing power generation even when some power generation systems among a plurality of power generation systems are unable to generate power or have reduced power generation.

  The fuel cell system of the present invention includes a reformer that reforms a raw fuel gas, a raw fuel pump that supplies the raw fuel gas to the reformer, a water pump that supplies water to the reformer, A stack to which the reformed gas generated in the reformer is supplied; a blower for supplying air to the stack; and an on-off valve for opening and closing the raw fuel gas supply path to the reformer. A plurality of power generation systems, one upstream raw fuel supply path that supplies the raw fuel gas to the supply paths of the plurality of power generation systems, and a part of the plurality of power generation systems are unable to generate power. A control device that controls the on-off valves of only the part of the power generation system to close when the power generation amount of the part of the power generation system drops below a predetermined amount. To do.

  In the fuel cell system of the present invention, the control device is configured such that a part of the power generation systems when a part of the power generation systems of the plurality of power generation systems becomes unable to generate power or when the power generation amount of the part of the power generation systems decreases. However, some power generation systems are stopped while other power generation systems continue to generate power, and some of the power generation systems generate power. Power generation can be continued even if it becomes impossible or power generation is reduced.

It is a block diagram showing a fuel cell system having a plurality of power generation systems. It is a block diagram which shows a power generation system, a hot water storage unit, and these connections. It is a perspective view which shows the state which contacted and arrange | positioned four housing | casings (fuel cell module) in which the stack was accommodated. It is an external appearance perspective view which shows a fuel cell module. It is sectional drawing of the fuel cell module shown in FIG.

  FIG. 1 is a block diagram showing an embodiment of a fuel cell system including four power generation systems (fuel cell devices) 1 (1a, 1b, 1c, 1d). FIG. 1 shows a case where a solid oxide fuel cell is used as the fuel cell device. In the following description, a solid oxide fuel cell will be described as an example of the fuel cell.

  As shown in FIGS. 1 and 2, the fuel cell system is connected to four power generation systems 1 (1a, 1b, 1c, 1d) and the respective power generation systems 1, and stores hot water after heat exchange. One hot water storage unit 2 and a circulation pipe 15 for circulating water between the power generation system 1 and the hot water storage unit 2 are configured. The power generation system 1 and the hot water storage unit 2 are shown in FIG. In FIG. 2, a state where the hot water storage unit 2 is connected to one power generation system 1 is described, but actually, one hot water storage unit 2 is connected to four power generation systems 1.

  The power generation system 1 is connected to a system power source, a fuel cell stack (hereinafter sometimes referred to as a stack) 5 that generates power with fuel gas and air, a raw fuel supply pipe 18 that supplies raw fuel such as city gas, An air supply pipe 19 for supplying air to the stack 5 and a reformer 3 for reforming the raw fuel with the raw fuel and air or steam are provided.

  The raw fuel supply pipe 18 includes an electric raw fuel pump 35, and the raw fuel pump 35 supplies raw fuel such as city gas and propane gas to the reformer 3. The air supply pipe 19 includes an electric blower 37, and air is supplied to the stack 5 by the blower 37. The reformer 3, the stack 5, the raw fuel supply pipe 18, and the air supply pipe 19 constitute a stack device 21, and the fuel cell module 4 is accommodated by housing the stack device 21 in an alloy case 22 described later. It is configured. Each of the power generation systems 1 (1a, 1b, 1c, 1d) includes a stack 5.

  A flow meter 39 for measuring the flow rate of the raw fuel gas is disposed on the upstream side of the raw fuel pump 35 of the power generation system 1, and on the upstream side of the flow meter 39, an opening and closing for opening and closing a supply path composed of the raw fuel supply pipe 18. A valve 41 is arranged. As shown in FIG. 1, one upstream raw fuel supply pipe 45 is connected to each raw fuel supply pipe 18 of the power generation system 1 (1a, 1b, 1c, 1d). The supply pipe 45 is provided with a desulfurizer 47.

  As will be described later, the fuel cell module 4 (hereinafter sometimes referred to as a module) as shown in FIGS. 4 and 5 is configured by housing the stack 5 and the reformer 3 in the housing 22. . In FIG. 2, the module 4 is surrounded by a two-dot chain line.

In the fuel cell system shown in FIG. 2, the condensed water treatment device 9 for treating the condensed water generated by the heat exchanger 8 and the water (pure water) treated by the condensed water treatment device 9 are used. A water tank 11 for storing water is provided, and the water tank 11 and the heat exchanger 8 are connected by a condensed water supply pipe 10. The heat exchanger 8 of the power generation system 1 and the hot water storage tank 16 of the hot water storage unit 2 are connected by a circulation pipe 15 that circulates water. The heat exchanger 8 is configured to exchange heat between exhaust gas (exhaust heat) generated by power generation of the stack 5 of the power generation system 1 and water of the hot water storage unit 2.

  In addition, depending on the quality of the condensed water produced | generated by the heat exchange in the heat exchanger 8, it can also be set as the structure which does not provide the condensed water processing apparatus 9. FIG. Moreover, when the condensed water processing apparatus 9 has the function to store water, it can also be set as the structure which does not provide the water tank 11. FIG.

  The water tank 11 and the reformer 3 are connected by a water supply pipe 13, and the water supply pipe 13 is provided with a water pump 12 that is a water supply device, and the water stored in the water tank 11 is stored in the water tank 11. The water pump 12 is configured to be supplied to the reformer 3.

  Further, the power generation system 1 shown in FIG. 2 includes, as auxiliary equipment, a power conditioner (supplied power adjustment unit) 6, a ventilation fan (not shown) of the power conditioner 6, a raw fuel pump 35 of the raw fuel supply pipe 18, In addition to the blower 37 of the air supply pipe 19, various sensors in the housing 22, a circulation pump 17 that circulates water in the circulation pipe 15, an outlet water temperature sensor 14, an ignition device that will be described later, and the like are provided.

  The power generation system 1 (1a, 1b, 1c, 1d) of the fuel cell system shown in FIG. 1 also has the auxiliary equipment shown in FIG. 2, but in FIG. Only a part of the raw fuel pump 35, the blower 37 of the air supply pipe 19, the flow meter 39 for detecting the flow rate of the raw fuel gas, the open / close valve 41 for opening and closing the supply path of the raw fuel supply pipe 18 and the like are shown.

  The power conditioner 6 converts the DC power generated by the module 4 into AC power and adjusts the amount of the converted power supplied to an external load. The outlet water temperature sensor 14 is provided at the outlet of the heat exchanger 8 and measures the water temperature of water (circulated water stream) flowing through the outlet of the heat exchanger 8.

  In the present embodiment, as shown in FIG. 1, there are four power generation systems 1 (1a, 1b, 1c, 1d), and one hot water storage unit 2 has four power generation systems 1 (1a, 1b). 1 c, 1 d), heat exchange is performed in the heat exchanger 8 of each power generation system 1 (1 a, 1 b, 1 c, 1 d), and hot hot water is stored in the hot water storage tank 16.

  In the present embodiment, the control device 7 is configured such that when some of the power generation systems 1 of the plurality of power generation systems 1 cannot generate power, or when the power generation amount of some of the power generation systems 1 decreases below a predetermined amount. In addition, the raw fuel gas on-off valve 41 of only some of the power generation systems 1 is controlled to be closed. The predetermined amount is, for example, 80% or less of the rated power generation amount of the power generation system 1.

  In such a fuel cell system, for example, when an auxiliary machine of the power generation system 1a out of the four power generation systems 1 (1a, 1b, 1c, 1d) fails, the control device 7 controls the power generation system 1a. Only the on-off valve 41 of the raw fuel gas is closed. Thereby, while power generation in the stack 5 of the power generation system 1a is stopped, power generation in the power generation systems 1b, 1c, and 1d is continued, so that power generation can be continued as a fuel cell system.

  In addition, when a part of the power generation system 1 cannot generate power or the amount of power generation decreases, a signal prompting maintenance can be transmitted or displayed on a remote controller of the system.

  Furthermore, the stack deterioration state is confirmed from the voltage of each stack 5, and the maximum output of each stack 5 is suppressed according to the deterioration state. By suppressing the maximum output, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. Specifically, the maximum output is determined for each stack 5 based on the output and voltage table stored in the control unit memory.

  Further, the stack deterioration state is confirmed from the voltage of each stack 5, and the fuel utilization rate of each stack 5 is controlled according to the deterioration state. By controlling the fuel utilization rate, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. Specifically, for each stack 5, based on the output and voltage table stored in the control unit memory, when the voltage falls below the threshold, the fuel utilization rate is lowered.

  Furthermore, the stack deterioration state is confirmed from the representative temperature of each stack 5, and the maximum output of each stack 5 is suppressed according to the deterioration state. By suppressing the maximum output, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. Specifically, the maximum output is determined for each stack 5 based on the output and temperature table stored in the control unit memory.

  Further, the stack deterioration state is confirmed from the representative temperature of each stack 5, and the air utilization rate of each stack 5 is controlled according to the deterioration state. By controlling the air utilization rate, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. Specifically, for each stack 5, based on the output and temperature table stored in the control unit memory, if the representative temperature of the stack 5 rises above the threshold, the air utilization rate is lowered. Alternatively, for each stack 5, based on the output and temperature table stored in the control unit memory, if the representative temperature of the stack 5 falls below the threshold, the air utilization rate is increased.

  Further, the stack deterioration state is confirmed from the representative temperature of each stack 5, and the fuel utilization rate of each stack 5 is controlled according to the deterioration state. By controlling the fuel utilization rate, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. Specifically, for each stack 5, based on the output and temperature table stored in the control unit memory, when the representative temperature of the stack 5 rises above the threshold, the fuel utilization rate is raised. Alternatively, for each stack 5, based on the output and temperature table stored in the control unit memory, when the representative temperature of the stack 5 falls below the threshold, the fuel utilization rate is lowered.

Further, the stack deterioration state is confirmed from the representative temperature of each stack 5, and the S / C (ratio of reforming water and fuel gas) of each stack is controlled according to the deterioration state. By controlling the S / C, deterioration of the stack 5 can be delayed. Alternatively, the life of the stack 5 can be extended. As a specific operation method, for each stack 5, based on the output and temperature table stored in the control unit memory, when the representative temperature of the stack 5 rises above the threshold, S / C is set. Raise. Or, for each stack 5, based on the output and temperature table stored in the control unit memory, if the representative temperature of the stack 5 falls below the threshold, the S / C is lowered.

  FIG. 3 shows a state in which four modules that house the stack device 21 in the housing 22 are arranged in contact with or close to each other. In these modules, the supply position of raw fuel gas and water is the position of the opposite surface of the housing between adjacent modules, and the supply position of air and the exhaust gas discharge position are opposite between adjacent modules. The temperature of each module can be made uniform.

Then, the control device 7 cannot increase the power generation or the power generation amount is reduced, for example, to increase the temperature of the casing 22 of the power generation systems 1b, 1c, and 1d adjacent to the casing 22 in which the stack 5 of the power generation system 1a is accommodated. At least one of the raw fuel pump 35, the water pump 12, and the blower 37 is controlled. For example, the amount of raw fuel supplied by the raw fuel pump 35 is increased, and the fuel utilization rate of the stack 5 of the power generation systems 1b, 1c, and 1d adjacent to the power generation system 1a is decreased. As a result, surplus fuel gas that has not been used for power generation of the fuel cell burns, the temperature in the housing 22 of the power generation systems 1b, 1c, and 1d can be improved, and the optimum temperature as the fuel cell system can be maintained.

  Further, for example, the air supply amount by the blower 37 is decreased, and the air utilization rate of the stack 5 of the power generation systems 1b, 1c, and 1d adjacent to the power generation system 1a is increased. As a result, the amount of air supplied to the housing 22 of the power generation systems 1b, 1c, and 1d can be reduced, so that the temperature inside the housing 22 of the power generation systems 1b, 1c, and 1d can be improved, and the optimum temperature for the fuel cell system can be achieved. Can be maintained.

  Further, for example, the supply amount by the water pump 12 and the raw fuel pump 35 is controlled, and the S / C (ratio of reformed water and fuel gas) of the power generation systems 1b, 1c, 1d adjacent to the power generation system 1a is reduced, The temperature in the housing 22 of the power generation systems 1b, 1c, and 1d can be improved, and the optimum temperature as the fuel cell system can be maintained.

  4 and 5 show one mode of the module 4 constituting the power generation system 1, FIG. 4 is an external perspective view showing the module 4, and FIG. 5 is a cross-sectional view of the module 4 shown in FIG.

  In the module 4 shown in FIG. 4, a stack in which the lower ends of a plurality of columnar fuel cells 23 are fixed to a gas tank 24 with an insulating bonding material (not shown) such as a glass sealing material inside a housing 22. The stacking device 21 having two 5 is housed. The stack 5 is arranged in a row in a state where a plurality of fuel cells 23 are erected, and adjacent fuel cells 23 are electrically connected in series via a current collecting member (not shown). . The fuel cell 23 has a gas flow path (not shown) through which fuel gas flows.

  At both ends of the stack 5, conductive members having current drawing portions for collecting the electricity generated by the power generation of the stack 5 (fuel cell 23) and drawing it out are arranged (not shown). ) 4 shows a case where the stack device 21 includes two stacks 5, the number of the stack devices 21 can be changed as appropriate. For example, only one stack 5 may be provided. Three or more may be provided.

  Further, the casing 22 is provided with an electric ignition device for burning fuel gas that has passed through a fuel cell 23 described later, and a thermocouple for measuring the temperature in the module 4.

  In FIG. 4, the fuel cell 23 is a hollow flat plate type having a gas flow path through which fuel gas flows in the longitudinal direction. A fuel electrode layer, a solid electrolyte is formed on the surface of a support having the gas flow path. 1 illustrates a solid oxide fuel cell 23 in which a layer and an oxygen electrode layer are sequentially laminated. In addition, in the fuel cell 23, it can also be set as the shape which has a gas flow path through which air distribute | circulates the inside in a longitudinal direction. In this case, an oxygen electrode layer, a solid electrolyte layer, and a fuel electrode layer are provided in this order from the inside, and the configuration of the module 4 may be changed as appropriate. Furthermore, the fuel battery cell 23 is not limited to the hollow plate type, and may be a plate type or a cylindrical type, for example, and it is preferable to change the shape of the housing 22 as appropriate.

  Further, in the module 4 shown in FIG. 4, the reformer 3 is disposed above the stack 5 in order to obtain fuel gas used for power generation of the fuel cell 23. A raw fuel such as city gas is supplied to the reformer 3 through a raw fuel supply pipe 18 and reformed to generate a fuel gas containing hydrogen gas.

  The reformer 3 can have a structure capable of performing steam reforming, which is an efficient reforming reaction, and partial oxidation reforming, and includes a vaporization unit 26 for vaporizing water, And a reforming unit 25 in which a reforming catalyst (not shown) for reforming fuel into fuel gas is disposed.

As the reforming catalyst, a combustion catalyst capable of partial oxidation reforming in addition to steam reforming can be used.

  Then, as shown in FIG. 4, the fuel gas (hydrogen-containing gas) generated by the reformer 3 is supplied to the gas tank 24 through the fuel gas circulation pipe 27, and enters the fuel cell 23 from the gas tank 24. It is supplied to the gas flow path provided. Note that the configuration of the stack device 21 can be changed as appropriate depending on the type and shape of the fuel cell 23. For example, the reformer 3 can be included in the stack device 21.

  Further, FIG. 4 shows a state in which a part (front and rear surfaces) of the housing 22 is removed and the stack device 21 housed inside is taken out rearward. Here, in the module 4 shown in FIG. 4, the stack device 21 can be slid and housed in the housing 22.

  Note that an air introduction member 29 for supplying air is arranged inside the housing 22 so that air flows from the lower end portion toward the upper end portion on the side of the fuel cell 23. The air introduction member 29 is disposed between the stacks 5 juxtaposed in the gas tank 24.

  As shown in FIG. 5, the casing 22 constituting the module 4 has a double structure having an inner wall 33 and an outer wall 34, and an outer frame of the casing 22 is formed by the outer wall 34, and a stacking device is formed by the inner wall 33. A power generation chamber 35 for accommodating 21 is formed. Further, in the housing 22, an air flow path 40 through which air introduced into the fuel cell 23 circulates between the inner wall 33 and the outer wall 34. An air introduction member 29 is connected to the air flow path 40.

  Here, an air introduction member 29 is inserted through the inner wall 33 and fixed in the housing 22. The air introduction member 29 includes an air inlet (not shown) through which air flows into the upper end side from the upper portion of the housing 22 and a flange portion 44, and introduces air into the lower end portion of the stack 5 at the lower end portion. An air outlet is provided for this purpose.

  In FIG. 5, the air introduction member 29 that introduces air into the housing 22 is arranged so as to be positioned between the two stacks 5 juxtaposed inside the housing 22. It can arrange | position suitably according to a number. For example, when only one stack 5 is accommodated in the housing 22, two air introduction members 29 can be provided and disposed so as to sandwich the stack 5 from both sides.

  Further, in the power generation chamber 35, there is a heat insulating member 37 for maintaining the temperature in the module 4 at a high temperature so that the heat in the module 4 is extremely dissipated and the temperature of the stack 5 does not decrease to reduce the amount of power generation. It is provided as appropriate.

  The heat insulating member 37 is preferably arranged in the vicinity of the stack 5. In particular, the heat insulating member 37 is arranged on the side surface side of the stack 5 along the arrangement direction of the fuel cell 23, and the arrangement of the fuel cell cells 23 on the side surface of the stack 5. It is preferable to arrange the heat insulating member 37 having a width equal to or greater than the width along the direction.

  Further, an exhaust gas inner wall 39 is provided on the inner side of the inner wall 33 along the arrangement direction of the fuel cells 23, and the exhaust gas in the power generation chamber 35 is located between the inner wall 33 and the exhaust gas inner wall 39 from above. The exhaust gas flow path 41 flows downward. The exhaust gas passage 41 communicates with an exhaust hole 45 provided at the bottom of the housing 22.

Thereby, the exhaust gas generated by the operation of the module 4 flows through the exhaust gas passage 41 and is then exhausted from the exhaust hole 45. The exhaust hole 45 may be formed by cutting out a part of the bottom of the housing 22 or may be formed by providing a tubular member.

  Here, in the module 4, electric ignition devices for igniting fuel gas that has passed through the fuel cell 23 described later are inserted so as to be positioned between the fuel cell 23 and the reformer 3. Has been.

  In a solid oxide fuel cell, the temperature at which the fuel cell 23 can generate power is high. Therefore, it is necessary to raise the temperature of the module 4 to a high temperature in the startup process of the fuel cell system. The normal operation process of the system requires the module 4 to be kept at a high temperature. Here, in the module shown in FIG. 4 and FIG. 5, the temperature of the module 4 can be improved by operating the ignition device and burning the fuel gas that has passed through the fuel cell 23. 4 activation processing can be performed. In addition, the temperature of the reformer 3 can be improved.

  Note that a thermocouple for measuring the temperature in the vicinity of the stack 5 is disposed inside the air introduction member 29, and the temperature measuring portion of the thermocouple is the central portion in the longitudinal direction of the fuel cell 23 and the fuel cell. It arrange | positions so that it may be located in the center part in the sequence direction of the cell 23. FIG.

  Here, the normal startup process and the normal operation process of the fuel cell system will be described. First, the electric raw fuel pump 35 of the raw fuel supply pipe 18 and the electric blower 37 of the air supply pipe 19 are operated. At this time, since the temperature of the module 4 is low, the power generation in the fuel cell 23 and the reforming reaction in the reformer 3 are not performed.

  Next, the ignition device provided in the module 4 of the power generation system 1 is operated. As a result, the fuel gas supplied from the raw fuel pump 35 of the raw fuel supply pipe 18 and passed through the stack 5 burns, and the temperature of the module 4 and the reformer 3 rises due to the combustion heat. When the temperature of the reformer 3 reaches a temperature at which steam reforming is possible, the water pump 12 is operated to supply water to the reformer 3. As a result, the reformer 3 generates a fuel gas that is a hydrogen-containing gas necessary for power generation of the fuel battery cell 23. When the fuel cell 23 reaches a temperature at which power generation can be started, it starts power generation using the fuel gas generated by the reformer 3 and the air supplied from the air supply pipe 19.

  Here, the start-up process of the fuel cell system is completed and switched to the normal operation process. The electric power generated in the stack 5 is converted into alternating current by the power conditioner 6, and then supplied and controlled to the external load by the control device 7 in response to a request from the external load. It is controlled so that the power from the stack 5 is supplied instead of the power supply.

  The control device 7 controls the operation of the electric blower 37 of the air supply pipe 19 so as to supply air necessary for the amount of power generated by the stack 5. Thus, the operation of the electric raw fuel pump 35 of the raw fuel supply pipe 18 is controlled so as to generate the necessary fuel gas corresponding to the power generation amount of the stack 5, and The operation of the water pump 12 is controlled.

  The exhaust gas generated by the operation of the stack 5 is supplied to the heat exchanger 8 and is heat-exchanged with water flowing through the circulation pipe 15. Hot water generated by heat exchange in the heat exchanger 8 flows through the circulation pipe 15 and is stored in the hot water storage tank 16. On the other hand, water contained in the exhaust gas discharged from the stack 5 by heat exchange in the heat exchanger 8 becomes condensed water, and is supplied to the condensed water treatment device 9 through the condensed water supply pipe 10. The condensed water is converted to pure water by the condensed water treatment device 9 and supplied to the water tank 11. The water stored in the water tank 11 is supplied to the reformer 3 through a water supply pipe 13 by an electric water pump 12 that is a water supply device. Thus, water self-sustained operation can be performed by effectively using condensed water.

  Although the present embodiment has been described in detail above, the present embodiment is not limited to the example of the above-described embodiment, and various changes, improvements, and the like can be made without departing from the scope of the present embodiment. Is possible.

  For example, although the fuel cell system having four power generation systems has been described in the above embodiment, any fuel cell system having a plurality of power generation systems may be used.

1, 1a, 1b, 1c, 1d: Power generation system 3: Reformer 4: Fuel cell module 5: Stack 7: Controller 8: Heat exchanger 12: Water pump 17: Circulation pump 18: Raw fuel supply pipe 19: Air supply pipe 21: Stack device 22: Housing 35: Raw fuel pump 37: Blower 39: Flow meter 41: On-off valve 45: Upstream raw fuel supply pipe

Claims (3)

  A reformer that reforms the raw fuel gas, a raw fuel pump that supplies the raw fuel gas to the reformer, a water pump that supplies water to the reformer, and the reformer A plurality of power generation systems comprising a stack to which reformed gas is supplied, a blower for supplying air to the stack, and an on-off valve for opening and closing the supply path of the raw fuel gas to the reformer; One upstream raw fuel supply path that supplies the raw fuel gas to the supply path of the power generation system and a part of the power generation systems of the plurality of power generation systems, or the part And a control device that controls the on / off valves of only the partial power generation systems to close when the power generation amount of the power generation system falls below a predetermined amount.   The stacks and the reformers of the plurality of power generation systems are each housed in a housing made of an alloy, and the plurality of housings are arranged in contact with or close to each other. The fuel cell system according to claim 1.   The control device controls at least one of the raw fuel pump, the water pump, and the blower so as to raise a temperature of a casing adjacent to a casing in which the stack of the partial power generation system is accommodated. The fuel cell system according to claim 2.

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