JP2011181198A - Fuel cell power generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell power generation system that follows the load variation beyond the rating and preventing service life from being shortened. <P>SOLUTION: First upper limit power which is maximum rated power, and second upper limit power exceeding the first upper limit power, are set as maximum generation power of a fuel cell 3, in a control part 5. When the required generation power of the fuel cell 3 exceeds the first upper limit power, the control part 5 changes the maximum generation power to the second upper limit power, and carries out at least one of an operation mode of improving carbon monoxide resistance of the fuel cell 3 and an operation mode of reducing carbon monoxide in hydrogen gas supplied to the fuel cell 3 by a fuel treating machine 1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel cell power generation system, and more particularly, to control for improving its convenience.

  A polymer electrolyte fuel cell uses hydrogen gas as fuel and oxygen-containing air as an oxidant. The polymer electrolyte fuel cell has a power generation capacity limit determined by design, and the generated power cannot be increased indefinitely. In view of this, it is general to set the rated upper limit value of the generated power in consideration of the power generation capacity and operate the fuel cell only within the range below that.

  When a fuel cell is installed in a home as a power generation system, a fuel processor is used that generates hydrogen gas by reforming a fuel gas such as city gas mainly composed of hydrocarbons such as methane with steam. In the reforming reaction, carbon dioxide and carbon monoxide derived from fuel gas are generated. Carbon monoxide poisons the fuel electrode catalyst of the fuel cell, lowering the power generation efficiency and reducing the life of the fuel cell. Therefore, the fuel processor has a carbon monoxide removal unit that reduces carbon monoxide. The fuel gas is further processed by the carbon monoxide removing unit, and is used after, for example, reducing the carbon monoxide concentration to about 10 ppm.

  Even if such a process is performed, the influence of poisoning by the fuel gas carbon monoxide may occur. For example, if the power generation amount of the fuel cell is increased within the rated upper limit, the absolute amount of fuel gas required for power generation increases, so the absolute amount of carbon monoxide increases and the influence of poisoning by carbon monoxide increases. . Therefore, conventionally, the influence of carbon monoxide is reduced by adding oxygen (air) to the fuel gas according to the power generation amount of the fuel cell (for example, Patent Documents 1 and 2).

  In addition, if the amount of power generated by the fuel cell is rapidly increased, the effect of poisoning by carbon monoxide also increases. In order to rapidly increase the amount of power generation, it is necessary to rapidly increase the amount of fuel gas sent to the fuel processor, and as a result, the carbon monoxide removal performance in the carbon monoxide removal unit is reduced. Therefore, a rated increase rate upper limit is generally determined for the rate of increase in the power generated by the fuel cell.

JP 2005-209547 A JP 2007-250294 A

  When the rated upper limit value of the power generation amount is determined as described above, the fuel cell cannot follow when the power consumption exceeds the rated upper limit value. For this reason, the use of equipment driven by the power of the fuel cell is restricted, or it may be necessary to supplement with commercial power.

  In addition, if an upper limit is set for the rate of increase in the power generated by the fuel cell, the fuel cell will follow when a device with relatively high power consumption is activated or when several devices are activated at once. Can not. As described above, when the power consumption increases rapidly (load increase rate) and exceeds the rated power increase rate upper limit value in the fuel cell, the generated power may not catch up.

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide a fuel cell power generation system that improves an insufficient power supply state of a fuel cell while suppressing the influence of carbon monoxide poisoning.

  In order to solve the conventional problems, a fuel cell power generation system of the present invention includes a fuel processor that reforms a raw material to generate hydrogen gas, a fuel cell that generates power using hydrogen gas as fuel, and a control unit. . In the control unit, a first upper limit power that is a rated upper limit power and a second upper limit power that exceeds the first upper limit power are set as the power generation upper limit power of the fuel cell. When the generated power required for the fuel cell exceeds the first upper limit power, the control unit changes the generated upper limit power to the second upper limit power. Along with this change, the control unit implements at least one of an operation mode for improving the carbon monoxide resistance of the fuel cell and an operation mode for reducing carbon monoxide in the hydrogen gas supplied to the fuel cell by the fuel processor. Let In the fuel cell power generation system of the present invention, as the rate of increase in power generated by the fuel cell in the control unit, a first increase rate upper limit value that is a rated increase rate upper limit value and a second increase that exceeds the first increase rate upper limit value. The rate upper limit is set. When the increase rate of the generated power required for the fuel cell exceeds the first increase rate upper limit value, the control unit changes the increase rate upper limit value of the generated power to the second increase rate upper limit value. Along with this change, at least one of an operation mode for improving the carbon monoxide resistance of the fuel cell and an operation mode for reducing carbon monoxide in the hydrogen gas supplied from the fuel processor is performed.

  According to the fuel cell power generation system of the present invention, power generation can be temporarily performed so as to exceed the rated upper limit value of the generated power of the fuel cell, so that it is possible to cope with a temporary increase in power consumption. Moreover, since the upper limit value of the power increase rate of the fuel cell can be temporarily increased, it is possible to follow a rapid load increase. At that time, poisoning of the fuel electrode by carbon monoxide can be minimized. With these configurations, the convenience of the fuel cell power generation system can be improved.

1 is a block diagram of a fuel cell power generation system according to Embodiment 1 of the present invention. 1 is a block diagram of a fuel processor of a fuel cell power generation system according to Embodiment 1 of the present invention. The schematic diagram which shows the relationship between the carbon monoxide density | concentration in the gas discharged | emitted from the transformation part of the fuel processor shown in FIG. 2, and reaction temperature Block diagram of a fuel cell power generation system according to Embodiment 2 of the present invention

(Embodiment 1)
FIG. 1 is a block diagram of a fuel cell power generation system according to Embodiment 1 of the present invention, and FIG. 2 is a block diagram of a fuel processor of the fuel cell power generation system. As shown in FIG. 1, the fuel cell power generation system includes a fuel processor 1, a fuel cell 3, a controller 5, a heat exchanger 7, and a hot water tank 9. The fuel processor 1 processes a raw material (raw material gas) such as city gas using water vapor or air, and generates a fuel gas mainly composed of hydrogen gas. That is, the fuel processor 1 reforms the raw material to generate hydrogen gas. The fuel cell 3 uses the hydrogen gas as fuel and generates power using air. In the present embodiment, the fuel cell 3 is a solid polymer fuel cell using a solid polymer thin film as an electrolyte.

  Hydrogen gas is supplied to a fuel electrode (not shown) of the fuel cell 3 and consumed by a reaction related to power generation in the fuel cell 3. However, since the fuel cell 3 cannot consume all the hydrogen gas in the fuel gas and use it for power generation, about 20% of the supplied hydrogen gas is discharged as the exhaust gas A together with carbon dioxide. This exhaust gas A is used by the fuel processor 1 to heat the reforming section 25 shown in FIG.

  On the other hand, air containing oxygen as an oxidant is supplied to an air electrode (not shown) of the fuel cell 3. Oxygen reacts with hydrogen gas supplied to the fuel electrode by a reaction related to power generation in the fuel cell 3 to become water. The water-derived water vapor, unreacted oxygen, unreacted nitrogen, and the like are discharged as exhaust gas B.

  The control unit 5 controls operations of the fuel processor 1, the fuel cell 3, and the like. A refrigerant (for example, water) is circulated between the heat exchanger 7 and the fuel cell 3. Thereby, the temperature of the fuel cell 3 is appropriately controlled. Although not shown, a pump and a flow valve for circulating the refrigerant are provided between the heat exchanger 7 and the fuel cell 3. The controller 5 also controls the operation of this pump and flow valve. The hot water tank 9 stores water (hot water) heated by the heat of the heat exchanger 7. This hot water is used for heating and hot water supply. The electric power generated by the fuel cell 3 is supplied to the load 11 via the inverter 10.

  Next, the configuration of the fuel processor 1 will be described with reference to FIG. The fuel processor 1 includes a desulfurization unit 21, a first mixing unit 23, a reforming unit 25, a shift conversion unit 27, a selective oxidation unit 29, and a second mixing unit 31. The desulfurization unit 21 removes sulfur compounds (for example, sulfur-based odorous components) that are contained in the source gas and poison the catalyst of the fuel cell 3. The first mixing unit 23 mixes the raw material gas desulfurized in the desulfurization unit 21 and water vapor at a predetermined ratio. The mixed gas is heated at 650 to 700 ° C. in the reforming section 25, and methane becomes hydrogen gas and carbon dioxide by the reaction of the formula (1). This reaction is generally called a reforming reaction. However, in parallel with this reaction, the reaction of the formula (2) occurs and carbon monoxide is generated at the same time.

  Carbon monoxide is generally contained in an amount of 10 to 15% of the reaction product gas, and needs to be removed to poison the fuel electrode catalyst of the fuel cell 3. Therefore, the reaction product gas is sent to the shift unit 27, where water vapor and carbon monoxide react at 160 to 250 ° C., and hydrogen gas and carbon dioxide are generated by the reaction of the formula (3). At this stage, the carbon monoxide concentration is reduced to about 0.5%. Equation (3) is called a shift reaction or CO shift reaction.

  This processing gas is further sent to the selective oxidation unit 29 and reacts with oxygen in the air at 150 to 200 ° C., and carbon dioxide is generated by the reaction of the formula (4). In this way, the carbon monoxide concentration is reduced to about 10 ppm. Equation (4) is called a selective oxidation reaction. The selective oxidation unit 29 is set in advance based on the amount of the raw material gas sent to the reforming unit 25 so that the equivalent amount of oxygen for oxidizing carbon monoxide is 1 and is 2 to 4 times the equivalent. Air is sent.

  Furthermore, the 2nd mixing part 31 is provided in case the carbon monoxide density | concentration increases. The second mixing unit 31 mixes air containing oxygen with the gas processed by the selective oxidation unit 29. This increases the oxygen concentration in the fuel gas and suppresses poisoning of the fuel electrode catalyst of the fuel cell 3 by carbon monoxide.

  Next, control by the control unit 5 will be described. In the control unit 5, the first upper limit power that is the rated upper limit power and the second upper limit power that exceeds the first upper limit power are set as the power generation upper limit power of the fuel cell 3. Normally, the control unit 5 operates the fuel cell 3 using the first upper limit power. That is, the control unit 5 controls the gas processing amount in the fuel processor 1 so that the generated power of the fuel cell 3 is less than or equal to the first upper limit power.

  When the generated power required for the fuel cell 3 in this state exceeds the first upper limit power, the control unit 5 changes the generated upper limit power to the second upper limit power. That is, when it is preferable to operate the fuel cell 3 beyond the first upper limit power, the control unit 5 operates the fuel cell 3 with the second upper limit power as the upper limit. The preferable case corresponds to the following case, for example. (A) When a device that consumes the power supplied from the fuel cell power generation system can be stably operated by increasing the amount of power supplied, (B) the electric power company unless the amount of power supplied is increased (C) When the breaker that limits the amount of power purchased from the power company runs out.

  Thus, when the control unit 5 operates the fuel cell 3 with the second upper limit power as the upper limit and actually exceeds the first upper limit power, catalyst poisoning by carbon monoxide at the fuel electrode of the fuel cell 3 is promoted. This is simply because the fuel flow rate increases and the absolute amount of carbon monoxide increases, and the modification reaction shown in equation (3) and the selective oxidation reaction shown in equation (4) are exothermic reactions. As described above, the reaction temperature in the reforming section 25 is about 650 to 700 ° C. As the gas processing amount increases, the amount of heat that the gas sent to the transformation unit 27 and the selective oxidation unit 29 carries to the transformation unit 27 and the selective oxidation unit 29 increases. Therefore, the temperature of the transformation unit 27 and the selective oxidation unit 29 is increased. As a result, it becomes difficult to proceed to the right side in the shift reaction (equation (3)) or the selective oxidation reaction (equation (4)), which is an equilibrium reaction. As a result, the concentration of carbon monoxide in the treated gas is increased.

  Therefore, the control unit 5 reduces the carbon monoxide in the hydrogen gas supplied to the fuel cell 3 by the operation mode that improves the carbon monoxide resistance of the fuel cell 3 and the switching of the upper limit power. At least one of the operation modes is performed.

  In the operation mode for improving the carbon monoxide resistance of the fuel cell 3, for example, the amount of heat dissipated by the heat exchanger 7 is decreased to raise the temperature of the fuel cell 3 and improve the carbon monoxide resistance of the fuel cell 3. For example, the rated operating temperature is about 60 ° C., and the operating temperature is temporarily raised to about 80 ° C. Therefore, the flow rate of the refrigerant | coolant circulated between the heat exchangers 7 is controlled by controlling a flow valve.

  Thus, when the temperature of the fuel cell 3 is raised, it becomes difficult for carbon monoxide to be adsorbed on the catalyst. Thereby, the carbon monoxide resistance of the fuel cell 3 can be improved.

  Alternatively, the amount of oxygen added in the second mixing unit 31 is increased, and the oxygen concentration in the hydrogen gas supplied to the fuel cell 3 by the fuel processor 1 is increased. For example, in a state where the upper limit power is operated at the first upper limit power, the second mixing unit 31 is adding about 0.6% of the fuel gas. When the upper limit power is switched to the second upper limit power, the second mixing unit 31 adds about 3% of air of the fuel gas. In this case, the carbon monoxide adsorbed on the catalyst can be oxidized with mixed oxygen.

  In the operation mode in which carbon monoxide in the hydrogen gas supplied from the fuel processor 1 to the fuel cell 3 is reduced, the flow rate of water vapor supplied to the shift unit 27 and the flow rate of air supplied to the selective oxidation unit 29 are increased. That is, at least one of the flow rate of water vapor and the flow rate of air supplied to the fuel processor 1 is increased. By either of these, the carbon monoxide in the hydrogen gas supplied from the fuel processor 1 is reduced. In this case, the reaction in the shift unit 27 and the selective oxidation unit 29 can be promoted.

  As described above, the operation mode for improving the carbon monoxide resistance of the fuel cell 3 and the operation mode for reducing carbon monoxide in the hydrogen gas supplied from the fuel processor 1 have the second upper limit power as an upper limit. This is limited while the fuel cell 3 is in operation.

  In addition, the control part 5 detects the generated electric power requested | required of the fuel cell 3 as follows, for example. The controller 5 detects the change in resistance on the output side of the inverter 10 and recognizes that the generated power required for the fuel cell 3 has increased if the resistance decreases.

  As described above, the exhaust gas A discharged from the fuel cell 3 is supplied to the fuel processor 1 as fuel for heating the reforming unit 25 of the fuel processor 1. When the amount of power generation increases and the amount of hydrogen gas contained in the exhaust gas A decreases, the temperature of the reforming unit 25 decreases. The control unit 5 can detect this temperature decrease and detect that the power generation amount in the fuel cell 3 has increased. Therefore, it is preferable to provide a temperature detection unit (not shown) in the reforming unit 25 and input the output to the control unit 5.

  Although the heat exchanger 7 and the hot water tank 9 are provided in FIG. 1, the fuel cell 3 may be simply cooled to a predetermined temperature with cooling water without providing them. In this case, an operation mode that improves the carbon monoxide resistance of the fuel cell 3 can be realized by reducing the flow rate of the cooling water or raising the temperature of the cooling water.

  Next, another control of the fuel cell power generation system according to the present embodiment will be described.

  Even when the power generation amount of the fuel cell 3 is suddenly increased, the influence of poisoning by carbon monoxide becomes large, and therefore, the upper limit value of the rated increase rate is generally determined for the increase rate of the power generated by the fuel cell. ing. Therefore, the fuel cell power generation system cannot follow when a device with relatively large power consumption is activated or when several devices are activated at once. Thus, the increase in power consumption (load increase rate) is so fast that it exceeds the rated power increase upper limit of the fuel cell, and the generated power may not catch up.

  The reason why the influence of poisoning by carbon monoxide becomes large when the power generation amount is rapidly increased in this way will be described with reference to FIG. FIG. 3 is a schematic diagram showing the relationship between the carbon monoxide concentration in the gas discharged from the shift unit 27 of the fuel processor shown in FIG. 2 and the reaction temperature.

  For example, assume a fuel cell 3 in which 750 W is rated power generation. When the amount of fuel gas corresponding to each power generation amount is processed by the shift unit 27, the concentration of carbon monoxide in the gas discharged from the shift unit 27 becomes a minimum value at a certain reaction temperature as shown in FIG. . For example, in the case of 250 W, the carbon monoxide concentration is lowest at 160 ° C., 180 ° C. in the case of 500 W, and 200 ° C. in the case of 750 W. This is because if the temperature is too low, the reaction rate does not follow, whereas if the temperature is too high, the reaction of the equation (4), which is an equilibrium reaction, does not proceed to the right. The latter is because the modification reaction is an exothermic reaction.

  When the power generation amount of the fuel cell 3 is rapidly increased from, for example, 250 W to 750 W, the shift unit 27 operated at 160 ° C. is required to rapidly increase the supply amount to the gas amount necessary for 750 W. However, if a gas corresponding to 750 W is processed at this temperature by the shift unit 27, the carbon monoxide concentration increases as shown by the arrow. When the carbon monoxide concentration after the shift reaction increases, the carbon monoxide concentration in the processing gas sent to the selective oxidation unit 29 increases. The increase in the carbon monoxide concentration is larger than the increase assumed when the power generation amount is increased from normal 250 W to 750 W, and the ratio of oxygen to carbon monoxide is reduced in the selective oxidation unit 29. Therefore, the selective oxidation property of carbon monoxide is reduced, and as a result, the concentration of carbon monoxide in the hydrogen gas sent to the fuel cell 3 is increased.

  It is preferable to control as follows for this problem. That is, the control unit 5 is provided with the first increase rate upper limit value that is the rated increase rate upper limit value and the second increase rate upper limit value that exceeds the first increase rate upper limit value as the increase rate upper limit value of the power generated by the fuel cell 3. Are set in advance. And the control part 5 changes the increase rate upper limit value of the electric power to generate | occur | produce to the 2nd increase rate upper limit value, when the increase rate of the generated power requested | required of the fuel cell 3 exceeds a 1st increase rate upper limit value. Along with this change, the control unit 5 includes at least an operation mode for improving the carbon monoxide resistance of the fuel cell 3 and an operation mode for reducing carbon monoxide in the hydrogen gas supplied to the fuel cell 3 by the fuel processor 1. Do one of them.

  That is, when it is preferable to operate the fuel cell 3 beyond the first increase rate upper limit value of the electric power, the control unit 5A operates the fuel cell 3 with the second increase rate upper limit value as the upper limit. The preferred case is a case where the required power amount on the side of the device that consumes the electric power supplied from the fuel cell power generation system largely changes to the increasing side, and the first increasing rate upper limit value cannot follow the increasing amount. Normally, the first increase rate upper limit value is, for example, about 1 W / sec. However, the above control can increase the increase rate upper limit value to about 2 W / sec, which is the second increase rate upper limit value.

  By controlling in this way, the upper limit value of the power increase rate of the fuel cell can be temporarily increased, so that it is possible to follow a rapid load increase rate. At that time, poisoning of the fuel electrode by carbon monoxide can be minimized. This control may coexist with the power upper limit switching control or may be realized independently.

(Embodiment 2)
FIG. 4 is a block diagram of a fuel cell power generation system according to Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to what makes the structure similar to Embodiment 1, and detailed description is abbreviate | omitted. 2 does not show the heat exchanger 7 and the hot water tank 9 in FIG. 1, they may be provided in the same manner as in FIG. The configuration of the fuel processor 1 is the same as the configuration of the first embodiment described with reference to FIG.

  In the present embodiment, a control unit 5A is provided instead of the control unit 5, and an estimation unit 41 and a storage unit 42 are provided. The control unit 5A has at least the same function as the control unit 5 described in the first embodiment. The estimation unit 41 receives a current value and a voltage value of the power generated by the fuel cell 3. The estimation unit 41 estimates the life of the fuel cell 3 from the current-voltage characteristics obtained from these values in a state where the control unit 5A sets the power generation upper limit power to the first upper limit power.

  When the fuel cell 3 is operated under the same operating conditions, the performance of the fuel cell 3 is reduced with the passage of the operating time, and the voltage value is reduced. The same operating condition means that the amount of hydrogen gas to be supplied, the dew point of hydrogen gas, the operating temperature, and the current value output from the fuel cell 3 are the same. When predicting the service life, the voltage value drop is measured / simulated in advance, and the operation time and voltage drop are tabulated. And the voltage value at the time of predicting the life is measured. From the voltage value and the above table, it is applied to which operating time the measured voltage value corresponds. Next, the difference from the operation time up to the voltage value set as the lifetime is calculated. In this way, the life of the fuel cell 3 can be estimated. What voltage value is determined as the life of the fuel cell 3 may be set by an individual device. For example, since a decrease in voltage value is synonymous with a decrease in power generation efficiency, the life of the fuel cell 3 may be set to be lower than the target power generation efficiency. Alternatively, when the same amount of power is generated as the voltage decreases, the amount of hydrogen gas required increases, so the life can be set in consideration of the hydrogen gas generation capability of the fuel processor 1.

  Further, the estimation unit 41 estimates a change in the life of the fuel cell 3 due to a change in the power generation operation of the fuel cell 3 by the control unit 5A. In other words, the estimation unit 41 estimates the influence on the lifetime due to changing the power generation upper limit power to the second upper limit power or changing the increase rate of the power to be generated to the second increase rate upper limit value as a change in lifetime. For example, data on how much the life per operation unit time is shortened by changing the operation condition is retained, and the time for driving exceeding the first upper limit power or the time for exceeding the first increase rate upper limit value is stored. Multiplying can be used to estimate shortening of life.

  The storage unit 42 holds the life value of the fuel cell 3 estimated by the estimation unit 41. The estimation unit 41 updates the life value of the fuel cell 3 held in the storage unit 42 when the estimated life value of the fuel cell 3 changes.

  For example, it is necessary to guarantee a lifetime of about 10 years for a household fuel cell power generation system. Therefore, the fuel cell 3 is designed to have a lifetime of 10 years even when operated at the rated upper limit. However, when operating above the rating as described above, the lifetime is somewhat shortened by carbon monoxide poisoning. By holding the lifetime value thus shortened in the storage unit 42, for example, operation exceeding the rating can be limited. As a result, a life of about 10 years can be assured.

  On the other hand, when it is often used at a relatively light load in normal operation, there may be a situation where the life of the fuel cell 3 far exceeds 10 years. Thus, when there is a margin in the life, the control unit 5A positively utilizes the operation exceeding the rating. That is, the control unit 5A compares the guaranteed lifetime value of the fuel cell 3 preset and stored in the storage unit 42 with the actually estimated value of the lifetime of the fuel cell 3, and according to the comparison result. The power generation upper limit power and the power increase rate upper limit value of the fuel cell 3 are changed. In this way, it is possible to flexibly cope with fluctuations in the load 11 while ensuring a guaranteed life.

  As described above, in the fuel cell power generation system of the present invention, the carbon monoxide resistance of the fuel cell is temporarily increased while raising the upper limit power generation rate of the fuel cell and the increase rate upper limit value of the generated power to a level exceeding the rated value. Improve or reduce the concentration of carbon monoxide. This can improve the convenience while suppressing the influence on the lifetime. The fuel cell power generation system according to the present invention is particularly useful as a system for stably supplying electric power at home.

DESCRIPTION OF SYMBOLS 1 Fuel processor 3 Fuel cell 5,5A Control part 7 Heat exchanger 9 Hot water tank 10 Inverter 11 Load 21 Desulfurization part 23 1st mixing part 25 Reforming part 27 Transformation part 29 Selective oxidation part 31 2nd mixing part 41 Estimation part 42 Memory

Claims (15)

A fuel processor that reforms the raw material to generate hydrogen gas;
A fuel cell for generating electricity using the hydrogen gas as a fuel;
A control unit,
In the control unit, as the power generation upper limit power of the fuel cell, a first upper limit power that is a rated upper limit power and a second upper limit power that exceeds the first upper limit power are set,
When the generated power required for the fuel cell exceeds the first upper limit power, the control unit changes the generated upper limit power to the second upper limit power and improves the carbon monoxide resistance of the fuel cell. A fuel cell power generation system that implements at least one of an operation mode for causing the fuel processor to reduce carbon monoxide in hydrogen gas supplied to the fuel cell. 2. The fuel cell power generation system according to claim 1, wherein the control unit raises an operating temperature of the fuel cell in an operation mode in which the carbon monoxide resistance of the fuel cell is improved. 2. The fuel cell power generation system according to claim 1, wherein the control unit increases an oxygen concentration in hydrogen gas supplied from the fuel processor in an operation mode in which the carbon monoxide resistance of the fuel cell is improved. The said control part increases at least one of the water flow volume supplied to the said fuel processor, and the flow volume of air in the operation mode which reduces the carbon monoxide in the hydrogen gas which the said fuel processor supplies to the said fuel cell. 2. The fuel cell power generation system according to 1. The control unit estimates the life of the fuel cell from the current-voltage characteristics of the fuel cell in a state where the power generation upper limit power is set to the first power upper limit power, and the control unit sets the power generation upper limit power to the second power generation upper limit power. 2. The fuel cell power generation system according to claim 1, further comprising an estimation unit configured to estimate a change in the life of the fuel cell caused by the change to the power generation upper limit power. A storage unit for holding a value of the lifetime of the fuel cell estimated by the estimation unit;
6. The fuel cell power generation system according to claim 5, wherein when the estimated lifetime value of the fuel cell changes, the estimation section updates the lifetime value of the fuel cell held in the storage section. A storage unit that holds a preset value of the guaranteed lifetime of the fuel cell;
The said control part compares the value of the guaranteed lifetime of the said fuel cell memorize | stored in the said memory | storage part with the value of the lifetime of the said fuel cell, and changes the said power generation upper limit electric power according to the comparison result. The fuel cell power generation system described. The control unit includes a first increase rate upper limit value that is a rated increase rate upper limit value and a second increase rate upper limit value that exceeds the first increase rate upper limit value as an increase rate upper limit value of power generated by the fuel cell. And are set,
The control unit changes the increase rate upper limit value of the power to be generated to the second increase rate upper limit value when the increase rate of the generated power required for the fuel cell exceeds the first increase rate upper limit value. And at least one of an operation mode for improving carbon monoxide resistance of the fuel cell and an operation mode for reducing carbon monoxide in hydrogen gas supplied to the fuel cell by the fuel processor. Item 4. The fuel cell power generation system according to Item 1. A fuel processor that reforms the raw material to generate hydrogen gas;
A fuel cell for generating electricity using the hydrogen gas as a fuel;
A control unit,
The control unit includes a first increase rate upper limit value, which is a rated increase rate upper limit value, and a second increase rate upper limit value, which exceeds the first increase rate upper limit value, as an increase rate upper limit value of power generated by the fuel cell. And are set,
The control unit changes the increase rate upper limit value of the power to be generated to the second increase rate upper limit value when the increase rate of the generated power required for the fuel cell exceeds the first increase rate upper limit value. And a fuel that implements at least one of an operation mode for improving the carbon monoxide resistance of the fuel cell and an operation mode for reducing carbon monoxide in hydrogen gas supplied to the fuel cell by the fuel processor. Battery power generation system. The fuel cell power generation system according to claim 9, wherein the control unit raises the operating temperature of the fuel cell in an operation mode in which the carbon monoxide resistance of the fuel cell is improved. 10. The fuel cell power generation system according to claim 9, wherein the control unit increases an oxygen concentration in hydrogen gas supplied from the fuel processor in an operation mode in which the carbon monoxide resistance of the fuel cell is improved. The control unit increases at least one of a flow rate of water vapor and an air flow supplied to the fuel processor in an operation mode in which carbon monoxide in hydrogen gas supplied to the fuel cell by the fuel processor is reduced. Item 10. The fuel cell power generation system according to Item 9. The control unit estimates the life of the fuel cell from the current-voltage characteristics of the fuel cell in a state where the power generation upper limit power is set to the first power upper limit power, and the control unit sets the power generation upper limit power to the second power generation upper limit power. The fuel cell power generation system according to claim 9, further comprising an estimation unit that further includes an estimation unit that estimates a change in the life of the fuel cell caused by the change to the power generation upper limit power. A storage unit for holding a value of the lifetime of the fuel cell estimated by the estimation unit;
The fuel cell power generation system according to claim 13, wherein the estimation unit updates the value of the life of the fuel cell held in the storage unit when the estimated value of the life of the fuel cell changes. A storage unit that holds a preset value of the guaranteed lifetime of the fuel cell;
The control unit compares the guaranteed lifetime value of the fuel cell stored in the storage unit with the lifetime value of the fuel cell, and changes the power generation upper limit power according to the comparison result. The fuel cell power generation system described.

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