JP2002367643A - Fuel cell power generating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell power generating system enabled to optionally set the ratio of electric output and thermal output. SOLUTION: The fuel cell power generating system has structural elements composed of a fuel reforming device 5 at least generating reformed gas from raw fuel 8, and a fuel cell main body 4 generating electric energy by the electrochemical reaction with the oxidant gas by using the reformed gas generated at the fuel reforming device 5 as deoxidant, and enabled to collect the heat exhausted from the above construction elements. Controlling conditions of the fuel reforming device 5 and the fuel cell main body 4 are set, and the system has a controlling device 14 controlling the state of operation of respective structural elements according to the above controlling conditions, and the ratio of electric output and thermal output of the system is enabled to optionally set according to the controlling conditions set at the controlling device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cogeneration type fuel cell power generation system, and in particular, to improve the operability as a cogeneration system by intentionally changing a ratio between an electric output and a heat output. The present invention relates to a fuel cell power generation system configured as described above.

[0002]

2. Description of the Related Art Normally, a fuel cell power generation system is operated at a fixed ratio between power generation efficiency and exhaust heat efficiency with respect to load conditions. FIG. 8 shows a schematic configuration of such a fuel cell system, which includes a fuel cell main body 4 including an anode 1, a cathode 2, and a cooling plate 3, a fuel reformer 5, a CO converter 6, and a steam separator. The container 7 is provided. Then, according to a command from the control device 14, the raw fuel 8 such as natural gas or LPG whose flow rate has been adjusted by the control valve 15 is mixed with the steam 9 separated from the steam separator 7 and introduced into the fuel reforming device 5. The reformed gas 10 obtained by the reforming reaction of the fuel reformer 5 is introduced into the CO converter 6, and the reducing agent 11, which has become a hydrogen-rich gas, is introduced into the anode 1 of the fuel cell main body 4. The air in the air whose flow rate has been adjusted by the fuel cell 16 is used as the oxidant 12
To the cathode electrode 2 of Thus, in the fuel cell main body 4, electric energy is generated by an electrochemical reaction between the reducing agent 11 and the oxidizing agent 12, thereby generating power. In this case, the respective amounts of the reducing agent 11 and the oxidizing agent 12 are adjusted to be appropriate amounts according to the power generation load and the battery current. The rest of the reducing agent 11 introduced into the fuel cell main body 4 that has not contributed to the power generation reaction is reused as a heating source of the fuel reformer 5.

In a cogeneration type fuel cell power generation system, heat generated in the fuel cell main body 4 is collected by a cooling plate 3 and taken out as heat from a heat exchanger 13 provided in a cooling water line. In addition, the combustion exhaust gas from the exhaust gas line of the fuel reformer 5 is collected and used by the heat exchanger 17.

FIG. 9 illustrates the energy flow of the fuel cell power generation system configured as described above. Assuming that the raw fuel energy j is 100, 87 is consumed in the fuel cell body 4 as the consumed energy k. 4 is consumed as the heat loss m of the fuel processing system. Further, 22 is consumed as the burner fuel 1 in the fuel reformer 5, of which 13 is reused as the reforming endotherm n and 9 is discharged as the reformer burner exhaust gas o. On the other hand, 87 of the energy consumption k in the fuel cell main body 4 is composed of 41 as the cell body generated heat p and 46 as the remaining battery DC power q. By recovering 41 of heat p, 50 is used as exhaust heat. In addition, 43 obtained by subtracting 3 as the power conversion loss r from 46 of the battery DC power q is the power generation end power s,
A value obtained by further subtracting 3 of the auxiliary power t from that is used as the power u at the transmission end.

[0005]

However, as described above, the respective amounts of the reducing agent 11 and the oxidizing agent 12 are controlled so as to be appropriate amounts according to the power generation load and the battery current. In a fuel cell power generation system in which the electrical efficiency and the exhaust heat efficiency are always operated at a constant ratio, the amount of exhaust heat recovered from the fuel cell body 4 is a constant amount depending on the power generation efficiency. However, it is not possible to meet demands such as wanting to use more heat, and to meet this demand, it is necessary to install additional equipment such as electric heaters and auxiliary boilers. There was a problem that it was disadvantageous economically.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a fuel cell power generation system capable of arbitrarily setting a ratio between an electric output and a heat output.

[0007]

According to the first aspect of the present invention,
A fuel reformer that generates reformed gas from at least raw fuel and a fuel cell body that generates electric energy by an electrochemical reaction with an oxidant using the reformed gas generated by the fuel reformer as a reducing agent In a fuel cell power generation system capable of recovering exhaust heat from these components, control means for setting control conditions for the components and controlling the operating state of each component by these control conditions is provided. And the ratio between the electric output and the heat output of the system can be arbitrarily set according to the control conditions of the control means.

According to a second aspect of the present invention, in the first aspect of the invention, the control means determines a flow rate of the air supplied to the fuel reformer or the flow rate of the air as a control condition for the constituent elements. It is characterized by changing the opening of the valve.

According to a third aspect of the present invention, in the first aspect of the present invention, the control means changes a set temperature of the fuel reformer as a control condition for the constituent elements.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the control means includes an amount of the oxidant supplied to the fuel cell body or an amount of the oxidant as a control condition for the constituent elements. The opening degree of the control valve to be determined is changed.

According to a fifth aspect of the present invention, in the first aspect of the invention, the control means changes a set temperature of the cooling water of the fuel cell main body as a control condition for the constituent elements.

The invention according to claim 6 is the invention according to claim 1, further comprising a selective oxidation reactor as the constituent element, wherein the control means controls the selective oxidation reaction as a control condition for the constituent element. The amount of fuel used as a heating source of the fuel reformer is changed by a reaction operation by changing an air flow rate supplied to the reactor or an opening degree of a control valve for determining the air flow rate.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the fuel reforming device comprises an autothermal reforming device, and the control means controls the auto-reforming device as the control condition for the component. It is characterized in that the amount of raw fuel supplied to the thermal reformer or the setting of the hydrogen utilization rate in the fuel cell body is changed.

As a result, according to the present invention, by setting the control conditions of the components such as the fuel reformer and the fuel cell main body, the relationship between the power generation efficiency and the exhaust heat efficiency of the system, that is, the electric output and the heat output, Can be set arbitrarily.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
This shows a schematic configuration of a fuel cell power generation system to which the embodiment of the present invention is applied, and the same parts as those in FIG. 8 are denoted by the same reference numerals.

In this case, a heat exchanger 17 is provided in the exhaust gas line of the fuel reformer 5, so that heat from the exhaust gas line can be recovered.

As shown in FIG. 2, the control device 14 as a control means includes a reformer burner air flow rate setting function a, an electric / heat output ratio setting value b, a reformer temperature setting function c, and a temperature comparison PI. It has a logic d and a fuel flow rate setting function e. Then, the reformer burner air flow rate set value is determined by the reformer burner air flow rate setting function a with respect to the fuel cell output, and the determined reformer burner air flow rate set value and electric / heat output ratio set value are determined. By controlling the control valve 18 with the value obtained by multiplying the fuel cell b by the multiplier 141 as the manipulated variable, the reformer burner air flow rate to the fuel reformer 5, that is, the amount of the oxidant 12 can be adjusted. A fuel flow rate setting value is determined for the output by a fuel flow rate setting function e, and a reformer temperature setting value is determined for the fuel cell output by a reformer temperature setting function c. A temperature comparison PI between the set value and the reformer temperature of the fuel reformer 5 detected by the temperature detector 19
Input to logic d to calculate the fuel flow correction amount, and control the value obtained by adding the calculated fuel flow correction amount and fuel flow set value determined by fuel flow setting function e by adder 142 as an operation amount. By controlling the valve 15, it is possible to adjust the flow rate of the raw fuel 8 mixed with the steam 9 and introduced into the fuel reformer 5.

In such a configuration, when a command is issued from the control device 14, the raw fuel 8 whose flow rate is adjusted by the control valve 15 and the steam 9 separated from the steam separator 7 are mixed, and the fuel reformer 5 Will be introduced. The reformed gas 10 obtained by the reforming reaction of the fuel reformer 5
Is introduced into the CO converter 6 and is introduced into the anode 1 of the fuel cell body 4 as a reducing agent 11 that has become a hydrogen-rich gas. In addition, air in the atmosphere whose flow rate has been adjusted by the control valve 16 in accordance with a command from the control device 14 is introduced into the cathode 2 of the fuel cell body 4 as the oxidant 12, and at this time, each of the reducing agent 11 and the oxidant 12 An electrochemical reaction occurs based on the amount, and power is generated in the fuel cell main body 4.

In this case, when the controller 14 increases the electric / heat output ratio set value b, the multiplied value of the multiplier 141 and the reformer burner air flow rate set value becomes larger, and is adjusted by the control valve 18. The reformer burner air flow to the fuel reformer 5 is increased, and the temperature in the fuel reformer 5 decreases. At this time, the control valve 15 provided in the fuel line
Is to maintain the reformer temperature of the fuel reformer 5,
Control is performed so as to increase the flow rate of the raw fuel 8 based on the reformer temperature of the fuel reformer 5 detected by the temperature detector 19. As a result, the temperature of the exhaust gas of the fuel reformer 5 increases, so that the amount of heat recovered from the heat exchanger 17 provided in the exhaust gas line of the fuel reformer 5 can be increased.

For example, the reformer burner air flow rate to the fuel reformer 5 adjusted by the control valve 18 is set to 1.25 times the normal operation time by the electric / heat output ratio set value b. In this case, the temperature in the fuel reformer 5 decreases, but at this time, the flow rate of the raw fuel 8 increases by about 2% in order to maintain the reformer temperature of the fuel reformer 5.

Accordingly, in the energy flow described in FIG. 9, when the power at the transmission end power u is maintained at 40, the raw fuel energy j increases from 100 to 102, which is a 2% increase. From 13.3 to 13.3. Further, since the burner fuel 1 in the fuel reformer 5 increases from 22 to 24, the amount of heat discharged by the reformer burner exhaust gas o becomes 10.74. Therefore, 1
When 0.74 is recovered, the amount of heat that can be used as exhaust heat increases from 50 in the related art to 51.74 in addition to 41 of the battery body generated heat p. Can be increased. On the other hand, as a result of the increase in the flow rate of the raw fuel 8, the power generation efficiency is reduced by about 0.8 points.

On the other hand, when the control device 14 decreases the set value of the electric / heat output ratio b, the flow rate of the reformer burner air to the fuel reformer 5 adjusted by the control valve 18 decreases. The temperature in the fuel reformer 5 rises. Then, the control valve 15 changes the flow rate of the raw fuel 8 based on the reformer temperature of the fuel reformer 5 detected by the temperature detector 19 in order to maintain the reformer temperature of the fuel reformer 5. Since the control is performed so as to decrease the amount of heat, the amount of exhaust heat can be reduced and the power generation efficiency can be increased.

In the above description, the reformer burner air flow rate set value determined by the reformer burner air flow rate setting function a is multiplied by the electric / heat output ratio set value b. Even if the reformer temperature of the fuel reformer 5 is directly changed by multiplying the reformer temperature set value determined by the function c by the electric / heat output ratio set value b, the same as described above is performed. The effect can be obtained.

(Second Embodiment) FIG. 3 shows a schematic configuration of a fuel cell power generation system to which a second embodiment of the present invention is applied, and the same parts as those in FIG. Is attached.

In this case, a temperature detecting device 20 is provided downstream of the cooling water line of the fuel cell body 4, and a temperature control valve 21 is provided upstream of the cooling water line. Can be collected.

The control device 14 has an electric / heat output ratio setting value b, a cathode air flow rate setting function f, a battery cooling water temperature setting value g, and a temperature comparison PI logic h. Then, the cathode air flow rate setting function f with respect to the fuel cell output
The cathode air flow rate set value is determined by the following equation, and the cathode air flow rate set value and the electric / heat output ratio set value b are multiplied by the multiplier 1
By controlling the control valve 16 using the value multiplied by 43 as an operation amount, the cathode air flow rate can be adjusted. On the other hand, the battery cooling water temperature set value g and the battery cooling water temperature detected by the temperature detection device 20 are used as the temperature. By inputting the result to the comparison PI logic h and calculating the flow rate of the battery cooling water so as to always become the battery cooling water temperature set value g, and controlling the temperature control valve 21 using the calculated result as an operation amount, the fuel cell Body 4
The flow rate of the battery cooling water in the cooling water line is adjustable.

According to such a configuration, when the control device 14 decreases the electric / heat output ratio set value b, the multiplier 1
The value multiplied by the cathode air flow rate set value at 43 becomes smaller, and the cathode air flow rate adjusted by the control valve 16, that is, the flow rate of the oxidizing gas 12 supplied to the cathode electrode 2 of the fuel cell main body 4, decreases. The oxidant utilization rate in the fuel cell body 4 increases, and the cell voltage decreases. As a result, the amount of heat generated in the fuel cell main body 4 increases, and the temperature of the cell cooling water increases.

At this time, the temperature regulating valve 21 installed upstream of the cooling water line is controlled so as to increase the flow rate to the heat exchanger 13 in order to maintain the battery cooling water temperature set value g. As a result, the amount of heat recovered from the cooling water of the fuel cell main body 4 can be increased, and accordingly, the amount of exhaust heat increases and the power generation efficiency can be reduced.

On the other hand, when the controller 14 increases the electric / heat output ratio set value b, the multiplied value by the cathode air flow rate set value in the multiplier 143 increases, and the cathode air adjusted by the control valve 16 is increased. The flow rate increases, the battery voltage of the fuel cell body 4 increases, and the temperature of the battery cooling water decreases. Then, the temperature regulating valve 21 is controlled so as to reduce the flow rate to the heat exchanger 13 in order to maintain the battery cooling water temperature set value g, whereby the heat amount recovered from the cooling water of the fuel cell body 4 is controlled. , The amount of exhaust heat can be reduced, and power generation efficiency can be increased.

In the above description, the set value of the cathode air flow rate determined by the cathode air flow rate setting function f is
Although the heat output ratio setting value b is multiplied, the battery cooling water temperature is directly varied by multiplying the battery cooling water temperature setting value g by the electric / heat output ratio setting value b. The effect can be obtained.

(Third Embodiment) FIG. 5 shows a schematic configuration of a main part of a fuel cell power generation system to which a third embodiment of the present invention is applied. And the same reference numerals.

In this case, the anode 1 of the fuel cell body 4
A selective oxidation reactor 22 and a heat exchanger 23 are provided on the downstream side of the anode 1 of the fuel cell body 4 on the upstream side of the fuel cell body 4 and on the downstream side of the anode 1 of the fuel cell body 4. The heat can be recovered. An air flow rate adjusting element 24 is connected to the selective oxidation reactor 22, and the air in the air whose flow rate is adjusted by the air flow rate adjusting element 24 according to a command from the control device 14 is used as the oxidant 12 to the selective oxidation reactor 22. I am trying to introduce it. Here, the selective oxidation reactor 22 selectively reacts and removes carbon monoxide. The selective oxidation reactor 22 varies the amount of hydrogen in the reformed gas used in the combustion reaction according to the flow rate of the introduced air, thereby changing the fuel consumption. The amount is adjustable.

As shown in FIG. 6, the control device 14 sets the selected oxidizing air flow rate setting function i, the electric / heat output ratio setting value b,
It has a reformer temperature setting function c, a temperature comparison PI logic d, and a fuel flow rate setting function e. Then, a selected oxidized air flow rate set value is determined by a selected oxidized air flow rate setting function i with respect to the fuel cell output, and the determined selected oxidized air flow rate set value and the electric / heat output ratio set value b are multiplied by a multiplier 14.
By giving the value multiplied by 1 to the air flow rate adjusting element 24 as the manipulated variable, the flow rate of the selected oxidized air to the selective oxidation reactor 22 can be adjusted. Others are the same as FIG. 2, and the description here is omitted.

In such a configuration, when the electric / heat output ratio set value b is increased in the control device 14, an instruction to increase the air flow rate of the oxidizing gas 12 is given to the air flow rate adjusting element 24. . Then, in the selective oxidation reactor 22, the amount of fuel used increases because the hydrogen in many reformed gases is used for the combustion reaction due to the increase in the flow rate of the selective oxidation air, and the heating source of the fuel reformer 5 is actually increased. And the reformer temperature decreases. At this time, the control valve 15 provided in the fuel line operates based on the reformer temperature of the fuel reformer 5 detected by the temperature detector 19 in order to maintain the reformer temperature of the fuel reformer 5. Control is performed to increase the flow rate of the raw fuel 8. As a result, the calorific value of the fuel gas increases, so that the anode electrode 1
The amount of heat recovered from the heat exchanger 23 installed on the upstream side can be increased, the amount of exhaust heat increases by that amount, and the power generation efficiency can be reduced.

On the other hand, when the controller 14 reduces the electric / thermal output ratio set value b, an instruction to reduce the air flow is given to the air flow adjusting element 24. Then
In the selective oxidation reactor 22, the combustion reaction of hydrogen in the reformed gas is suppressed by reducing the flow rate of the selective oxidation air.
The amount of fuel used decreases, the amount of fuel actually used for the heating source of the fuel reformer 5 increases, and the temperature of the reformer increases.
Then, the control valve 15 changes the flow rate of the raw fuel 8 based on the reformer temperature of the fuel reformer 5 detected by the temperature detector 19 in order to maintain the reformer temperature of the fuel reformer 5. Since the control is performed so as to decrease the amount of heat, the amount of exhaust heat can be reduced and the power generation efficiency can be increased.

(Fourth Embodiment) FIG. 7 shows a schematic configuration of a main part of a fuel cell power generation system to which a fourth embodiment of the present invention is applied. And the same reference numerals.

In this case, the anode 1 of the fuel cell body 4
An autothermal reformer 25 and a selective oxidation reactor 22 are provided as a fuel reformer on the upstream side, and an exhaust fuel combustor 26 is provided on the downstream side of the anode 1. The exhaust heat can be recovered from the exhaust fuel combustor 26.

In such a configuration, the control device 14 gives an instruction to the control valve 15 provided in the fuel line to increase the flow rate of the raw fuel 8, and the fuel supply amount to the autothermal reformer 25. When the energy consumption in the fuel cell main body 4 does not change under the condition of a constant electric output, the amount of exhaust fuel energy from the fuel cell main body 4 increases accordingly. The amount of exhaust heat supplied to the exhaust fuel combustor 26 increases, and the amount of heat recovery can be increased. For example, if the amount of energy input to the autothermal reformer 25 is increased from 100 to 110 under the condition of constant electric output, assuming that the energy consumption in the fuel cell main body 4 remains at 70, Fuel energy of 30 to 40
And the amount of exhaust heat recovered by the exhaust fuel combustor 26 can be increased accordingly. As a result, the amount of exhaust heat increases by that amount, and the power generation efficiency can be reduced.

On the other hand, if the amount of fuel supplied to the autothermal reformer 25 is reduced, the amount of fuel exhausted from the fuel cell body 4 is reduced, and the amount of exhausted fuel disposed downstream of the anode 1 is reduced. Since the amount of exhaust heat supplied to the heater 26 also decreases, the amount of exhaust heat can be reduced, and conversely, the power generation efficiency can be increased.

The air flow rate of the oxidizing gas 12 is controlled with respect to the autothermal reformer 25 to vary the setting of the hydrogen utilization rate in the fuel cell main body 4 so as to discharge the fuel from the fuel cell main body 4. By controlling the fuel energy amount, the relationship between the exhaust heat efficiency and the power generation efficiency can be set arbitrarily.

[0042]

As described above, according to the present invention, the relationship between the power generation efficiency and the exhaust heat efficiency of the system, that is, the electric power, is set by setting the control conditions of each component such as the fuel reformer and the fuel cell body. The ratio between the output and the heat output can be set arbitrarily. As a result, for example, even in a usage mode in which the ratio of electricity and heat demand fluctuates between summer and winter, there is no need to prepare auxiliary equipment such as a conventional electric heater or auxiliary boiler, and as a cogeneration type fuel cell power generation system It is possible to provide a power generation facility that can respond to a wide range of demands on electric load and heat load without any additional facilities.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a control device used in the first embodiment.

FIG. 3 is a diagram showing a schematic configuration of a second embodiment of the present invention.

FIG. 4 is a diagram showing a schematic configuration of a control device used in a second embodiment.

FIG. 5 is a diagram showing a schematic configuration of a main part according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a schematic configuration of a control device used in a third embodiment.

FIG. 7 is a diagram illustrating a schematic configuration of a main part according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a schematic configuration of a conventional fuel cell power generation system.

FIG. 9 is a diagram illustrating an energy flow of the fuel cell power generation system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Anode electrode 2 ... Cathode electrode 3 ... Cooling plate 4 ... Fuel cell main body 5 ... Fuel reformer 6 ... CO converter 7 ... Steam separator 8 ... Raw fuel 9 ... Steam 10 ... Reformed gas 11 ... Reducing agent 12 ... Oxidizing agent 13 ... Heat exchanger 14 ... Control device 15 ... Control valve 16 ... Control valve 17 ... Heat exchanger 18 ... Control valve 19 ... Temperature detection device 20 ... Temperature detection device 21 ... Temperature control valve 22 ... Selective oxidation reactor 23 heat exchanger 24 air flow regulating element 25 autothermal reformer 26 exhaust fuel combustor a reformer burner air flow setting function b electric / heat output ratio set value c reformer temperature Setting function d: Temperature comparison PI logic e: Fuel flow rate setting coefficient f: Cathode air flow rate setting function g: Battery cooling water temperature setting value h: Temperature comparison PI logic i: Selected oxidizing air flow rate setting function j: Raw fuel energy k ... Pond body consumption energy 1 ... Reformer burner fuel m ... Fuel treatment system heat loss n ... Reforming endotherm o ... Reformer burner exhaust gas p ... Battery body generated heat q ... Battery DC power r ... Power conversion loss s ... Power generation end Power t: auxiliary machine power u: power at the transmitting end

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Taiji Kogami 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture F-term in Toshiba Hamakawasaki Plant (reference) 5H027 BA01 KK28 KK42 MM12 MM16

Claims (7)

[Claims] 1. A fuel reformer for generating a reformed gas from at least a raw fuel, and a fuel for generating electric energy by an electrochemical reaction with an oxidant using the reformed gas generated by the fuel reformer as a reducing agent In a fuel cell power generation system having a battery body as a component and enabling exhaust heat to be recovered from the component, a control condition for the component is set, and an operation state of each component is set based on the control condition. A fuel cell power generation system comprising control means for controlling, wherein a ratio between an electric output and a heat output of the system can be arbitrarily set according to control conditions of the control means. 2. The control device according to claim 1, wherein the control unit changes an air flow rate supplied to the fuel reformer or an opening degree of a control valve for determining the air flow rate as a control condition for the constituent elements. The fuel cell power generation system as described in the above. 3. The fuel cell power generation system according to claim 1, wherein said control means changes a set temperature of said fuel reformer as a control condition for said constituent elements. 4. The control means changes the amount of an oxidant supplied to the fuel cell body or the opening of a control valve for determining the amount of the oxidant as a control condition for the constituent elements. The fuel cell power generation system according to claim 1. 5. The fuel cell power generation system according to claim 1, wherein said control means changes a set temperature of cooling water of said fuel cell main body as a control condition for said constituent elements. 6. The apparatus according to claim 6, further comprising a selective oxidation reactor as the component, wherein the control unit determines, as a control condition for the component, an air flow rate supplied to the selective oxidation reactor or the air flow rate. 2. The fuel cell power generation system according to claim 1, wherein an amount of fuel used for a heating source of the fuel reformer is changed by a reaction operation by changing a valve opening. 7. The fuel reforming apparatus includes an autothermal reforming apparatus, and the control unit controls a quantity of the raw fuel supplied to the autothermal reforming apparatus or the fuel as a control condition for the constituent elements. 2. The fuel cell power generation system according to claim 1, wherein the setting of the hydrogen utilization rate in the battery body is changed.