JP2012119244A - Fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine whether the amount of air supplied from an air supply section to a hydrogen generation device in a fuel cell system is appropriate.SOLUTION: There are included an air supply unit 19 which supplies air to a selective oxidation unit 17 according to an instruction value of air supply amount, a selective oxidation temperature detection unit 26 which detects the temperature of the selective oxidation unit, and an operation control unit 16 which outputs an instruction value of air supply amount to the air supply unit based on the selective oxidation temperature detected by the selective oxidation temperature detection unit. The operation control unit, for a preset period after a given power generation amount which the fuel cell has is generated, runs the fuel cell without tracking a change in electric power load and actuates the air supply unit with a preset instruction value. If a temperature difference between a predicated selective oxidation temperature predicted from the instruction value and the detected selective oxidation temperature detected by the selective oxidation temperature detection unit is equal to or greater than a prescribed temperature difference, the operation control unit determines that an amount of air corresponding to the preset instruction value is not supplied from the air supply unit as instructed.

Description

  The present invention relates to a fuel cell system including a hydrogen generator that generates a hydrogen-containing gas having a low carbon monoxide concentration from a fossil raw material or the like.

  Development of a fuel cell system using a fuel cell stack (hereinafter simply referred to as “fuel cell”) that enables high-efficiency power generation even with a small device as a distributed energy supply source is in progress. A fuel cell system supplies a hydrogen-containing gas and an oxygen-containing gas to a fuel cell, which is the main body of a power generation unit, and proceeds with an electrochemical reaction between hydrogen and oxygen to generate chemical energy. This is a system that generates electricity by taking it out as natural energy.

  In general, hydrogen-containing gas is not supplied from the infrastructure. Therefore, a conventional fuel cell system uses a city gas or LPG supplied from an existing infrastructure as a raw material, and reforms with a steam reaction at a temperature of 600 to 700 ° C. using a Ru catalyst or a Ni catalyst. A hydrogen generation apparatus having a section is provided. Note that the hydrogen-containing gas obtained by the reforming reaction usually contains carbon monoxide derived from the raw material, and when the concentration is high, the power generation characteristics of the fuel cell are degraded. Therefore, in addition to the reforming unit, the hydrogen generator has a Cu—Zn-based catalyst or a noble metal that reduces carbon monoxide by advancing a transformation reaction between carbon monoxide and water vapor at a temperature of 200 ° C. to 350 ° C. And a reaction section such as a selective oxidation section equipped with a Ru catalyst or a Pt catalyst, which selectively reduces carbon monoxide by selectively oxidizing carbon monoxide at a temperature of 100 ° C. to 200 ° C. Is provided. Further, in order to improve the efficiency of the fuel cell system, a hydrogen-containing gas (hereinafter referred to as “anode off gas”) discharged from the anode during power generation of the fuel cell is often burned by a hydrogen generator and used for the reforming reaction. .

  As described above, the hydrogen generator is composed of a reforming unit, a shift unit, a selective oxidation unit, and the like, and generates a certain amount of hydrogen and hydrogen with a low carbon monoxide concentration in a steady state and a transitional period. In order to achieve this, it is necessary to strictly control the temperature of the catalyst in each reaction section within a certain range. Therefore, a temperature detector is installed near the downstream side of the reforming unit, the transformation unit, and the selective oxidation unit. In the reforming unit, the heating amount of the reforming unit is increased or decreased based on the temperature detected by the temperature detector, and the selective oxidation is performed. In the unit, the temperature of each reaction unit is appropriately controlled by increasing or decreasing the cooling amount of the cooler provided on the upstream side based on the temperature detected by the temperature detector (for example, Patent Documents). 1). Also, the temperature of the shift section is appropriately controlled by increasing or decreasing the amount of water supplied to the preheating evaporator or increasing or decreasing the combustion air supply to the heating section based on the temperature detected by the temperature detector of the shift section. The structure is taken (for example, refer patent document 2).

JP 2001-180905 A JP 2008-0119159 A

  However, if the air supply amount corresponding to the air indication value is not properly supplied to the hydrogen generation device due to an abnormality in the air flow measurement means such as a flow meter that measures the air supply amount supplied from the air supply unit to the hydrogen generation device. A certain amount of hydrogen and hydrogen with a low carbon monoxide concentration cannot be produced. This leads to overheating of the selective oxidation unit or poisoning of the fuel cell with carbon monoxide, making it impossible to continue the power generation operation. Furthermore, it leads to failure of the fuel cell system.

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide a fuel cell system capable of grasping whether or not the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate easily and quickly. And

  In order to solve the above-described problems, in the fuel cell system of the present invention, a reforming unit that supplies a raw material and water and generates a hydrogen-containing gas by a reforming reaction, and a reforming temperature detection that detects the temperature of the reforming unit Generated by a reforming unit, a raw material supply unit that supplies a raw material according to a raw material supply amount instruction value to the reforming unit, a water supply unit that supplies water according to a water supply amount instruction value to the reforming unit, A shift section for reducing the carbon monoxide concentration in the generated hydrogen-containing gas, a shift temperature detection section for detecting the temperature of the shift section, and further reducing the carbon monoxide concentration in the hydrogen-containing gas reduced by the shift section A selective oxidation unit; an air supply unit that supplies air to the selective oxidation unit according to an air supply amount instruction value; a selective oxidation temperature detection unit that detects a temperature of the selective oxidation unit; and a carbon monoxide concentration in the selective oxidation unit. Reduced hydrogen-containing gas and oxygen-containing gas are supplied. A fuel cell that generates power following changes in the power load at the power supply destination, and a remaining hydrogen-containing gas that has not been consumed by the fuel cell among the hydrogen-containing gas whose carbon monoxide concentration has been reduced by the selective oxidation unit. Combustion unit that supplies the heat required for the reforming reaction of the reforming unit and operation control that outputs an air supply amount instruction value to the air supply unit based on the selective oxidation temperature detected by the selective oxidation temperature detection unit The operation control unit operates the fuel cell without following the change in the power load for a preset period after generating any amount of power generated by the fuel cell, and the air supply unit is preset. If the temperature difference between the predicted selective oxidation temperature expected from the indicated value and the detected selective oxidation temperature detected by the selective oxidation temperature detection unit is equal to or greater than the predetermined temperature difference, the preset indicated value Air corresponding to Those where the structure is determined not to be supplied to indicate street.

  As a result, it is possible to grasp whether or not the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate simply and quickly.

  According to the fuel cell system of the present invention, it is possible to determine whether the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate.

1 is a schematic configuration diagram of a fuel cell system according to Embodiment 1 of the present invention. The flowchart which shows typically 1 cycle of the characteristic operation | movement of the hydrogen generator in Embodiment 1 of this invention. The flowchart which shows typically 1 cycle of the characteristic operation | movement of the hydrogen generator in Embodiment 1 of this invention. The flowchart which shows typically 1 cycle of the characteristic operation | movement of the hydrogen generator in Embodiment 1 of this invention.

According to a first aspect of the present invention, there are provided a reforming section for supplying a raw material and water to generate a hydrogen-containing gas by a reforming reaction, a reforming temperature detecting section for detecting the temperature of the reforming section, and a raw material supply amount to the reforming section. A raw material supply unit that supplies a raw material according to the indicated value, a water supply unit that supplies water according to the water supply amount indicated value to the reforming unit, and carbon monoxide in the hydrogen-containing gas generated by the reforming unit A transformation section for reducing the concentration, a transformation temperature detection section for detecting the temperature of the transformation section, a selective oxidation section for further reducing the concentration of carbon monoxide in the hydrogen-containing gas reduced by the transformation section, and air in the selective oxidation section An air supply unit that supplies air according to the supply amount instruction value, a selective oxidation temperature detection unit that detects the temperature of the selective oxidation unit, and a hydrogen-containing gas and an oxygen-containing gas whose carbon monoxide concentration is reduced in the selective oxidation unit Is generated to follow the changes in the power load at the power supply destination. The heat required for the reforming reaction of the reforming unit by burning the remaining hydrogen-containing gas that has not been consumed in the fuel cell out of the hydrogen-containing gas whose carbon monoxide concentration has been reduced in the selective oxidation unit And an operation control unit that outputs an air supply amount instruction value to the air supply unit based on the selective oxidation temperature detected by the selective oxidation temperature detection unit. The operation control unit has a fuel cell Expected to be expected from the indicated value by operating the fuel cell without following the change in the power load and operating the air supply unit at the indicated value set in advance for a preset period after generating any power generation amount If the temperature difference between the selective oxidation temperature and the detected selective oxidation temperature detected by the selective oxidation temperature detection unit is greater than or equal to a predetermined temperature difference, air corresponding to a preset instruction value is supplied from the air supply unit as instructed. And the structure to judge that Those were. As a result, it is possible to grasp whether or not the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate simply and quickly.

  In particular, the operation control unit according to the second aspect of the present invention may be configured such that the temperature difference between the predicted selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than a predetermined temperature difference, and the detected selective oxidation is performed based on the predicted selective oxidation temperature. When the temperature is higher, it is determined that a large amount of air corresponding to the preset indicated value is supplied from the air supply unit, and when the detected selective oxidation temperature is lower than the expected selective oxidation temperature, the predetermined value is set in advance. It is determined that a small amount of air corresponding to the indicated value is supplied from the air supply unit. As a result, it is possible to appropriately grasp the increase or decrease in the amount of air supplied from the air supply unit to the hydrogen generator simply and quickly.

  In particular, the operation control unit according to the first aspect of the present invention may be configured so that the temperature difference between the predicted selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than a predetermined temperature difference, When the temperature is higher, control to decrease the indicated value to the air supply unit, and control to increase the indicated value to the air supply unit when the detected selective oxidation temperature is lower than the expected selective oxidation temperature It is. Accordingly, it is possible to determine whether the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate, and to correct the air supply amount corresponding to the air instruction value. As a result, a certain amount of hydrogen and hydrogen with a low carbon monoxide concentration can be generated. In addition, it is possible to prevent overheating of the selective oxidation unit, poisoning of the fuel cell due to carbon monoxide, and failure of the fuel cell system. Furthermore, air flow measurement means such as a flow meter is not required, and the cost of the fuel cell system can be reduced.

  In the fourth aspect of the invention, in particular, when the temperature difference between the predicted selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than a predetermined temperature difference, the air supply amount from the air supply unit is abnormal. It judges that there is, and outputs an alarm. Accordingly, it is possible to determine whether the amount of air supplied from the air supply unit to the hydrogen generator is abnormal and to output an alarm to the outside.

  Hereinafter, embodiments of the present invention will be described more specifically with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
<Configuration of fuel cell system>
FIG. 1 is a schematic configuration diagram showing Embodiment 1 of a fuel cell system according to the present invention.

  The fuel cell system 100 includes a hydrogen generator 1 that generates a hydrogen-containing gas, a fuel cell 8 that generates power using the hydrogen-containing gas supplied from the hydrogen generator 1, and a switch from the hydrogen generator 1 to the fuel cell 8. Hydrogen gas supply path 12 for supplying hydrogen gas via valve 9A, and off-gas supply path 14 for supplying anode off-gas discharged from fuel cell 8 to combustion section 2 of hydrogen generator 1 via switching valve 9B I have. The switching valve 9A is connected to the switching valve 9B by the fuel cell bypass path 23. In addition, since it is a structure equivalent to the general solid polymer type fuel cell 8, detailed description of another structure is abbreviate | omitted.

  The hydrogen generator 1 includes a water supply unit 3 that supplies water to the hydrogen generator 1 and a desulfurization unit 5 that allows a hydrocarbon-based raw material containing a sulfur component to pass therethrough and adsorbs and removes the sulfur component contained in the raw material. A reformer 22 that generates a hydrogen-containing gas using the raw material after passing through the desulfurization unit 5 and the water supplied from the water supply unit 3, and the flow rate of the raw material supplied to the desulfurization unit 5 (raw material) A raw material supply unit 4 for controlling the flow rate) and an operation control unit 16 for controlling operations of the raw material supply unit 4 and the water supply unit 3.

  The reformer 22 is spiral, evaporates the water supplied from the water supply unit 3, and advances the reforming reaction between the raw material and water vapor, and the water vapor generation unit 15 that preheats the mixed gas of the raw material and water vapor. The reforming unit 20 includes a shift unit 13 that performs a shift reaction of carbon monoxide and water vapor in the hydrogen-containing gas generated in the reforming unit 20 to reduce the carbon monoxide concentration of the hydrogen-containing gas. Further, the carbon monoxide remaining in the hydrogen-containing gas after passing through the shifter 13 is mainly oxidized using air supplied from the air supply unit 19 to the hydrogen-containing gas after passing through the shifter 13. And a selective oxidation portion 17 to be removed. The reforming section 20 is provided with a Ru-based reforming catalyst, the shift section 13 is provided with a Cu—Zn-based shift catalyst, and the selective oxidation section 17 is provided with a Ru-based selective oxidation catalyst. Further, a reforming temperature detection unit 21 that detects the temperature (reaction temperature) of the reforming catalyst (or hydrogen-containing gas) in the reforming unit 20, and the temperature (reaction temperature) of the shift catalyst (or hydrogen-containing gas) in the shift unit 13. Is provided with a shift temperature detector 24 for detecting the temperature, and a selective oxidation temperature detector 26 for detecting the temperature (reaction temperature) of the selective oxidation catalyst (or hydrogen-containing gas) in the selective oxidation unit 17.

  The reformer 22 includes a combustion unit 2 for supplying reaction heat necessary for the reforming reaction in the reforming unit 20. The combustion unit 2 includes a burner that burns combustion gas that serves as a heating source, and a combustion fan 18 that serves as a combustion air supply unit that supplies fuel air to the combustion unit 2. Combustion gas burned in the combustion unit 2 is supplied to the combustion unit 2 from the hydrogen gas supply path 12 via the fuel cell bypass path 23 or via the fuel cell 8 from the off-gas supply path 14. The hydrogen-containing gas generated by the reformer 22 is supplied to the fuel cell 8 through the hydrogen gas supply path 12.

  In addition, the reforming unit 20 and the steam generation unit 15 are configured to be supplied with heat from the flue gas generated in the combustion unit 2 through the wall surface of the inner cylinder 11. In addition, the steam generation unit 15 is configured to exchange heat with the transformation unit 13 and the selective oxidation unit 17 through the wall surface of the middle cylinder 25. In addition, in the structure of the modification part 20, the transformation part 13, and the selective oxidation part 17, the illustration about the same structure part as a general structure and detailed description are abbreviate | omitted.

  The hydrocarbon-based raw material supplied to the desulfurization section 5 may be a raw material containing an organic compound composed of at least carbon and hydrogen elements such as hydrocarbons, for example, city gas mainly composed of methane, natural gas, LPG or the like. Here, a city gas gas infrastructure line 6 is used as a raw material supply source, and a desulfurization section 5 is connected to the gas infrastructure line 6. The desulfurization part 5 has a shape that can be attached to and detached from the desulfurization connection part 7 disposed on the upstream side and the downstream side. When the adsorption amount of the desulfurization part 5 with respect to the sulfur component is saturated and the adsorption characteristic is lowered, a new desulfurization is performed. It can be exchanged for part 5. The desulfurization section 5 in the present embodiment is filled with a zeolite-based adsorption / removal agent that adsorbs a sulfur compound, which is an odorous component in city gas. Moreover, the desulfurization connection part 7 also has a valve function which controls the distribution | circulation of a raw material, for example, an electromagnetic valve is provided in a structure. In addition, the desulfurization part 5 is good also as a structure using hydrodesulfurization.

The water supply unit 3 has a pump having a flow rate adjusting function. The raw material supply unit 4 is disposed in the raw material supply path 10 that connects the desulfurization unit 5 and the reformer 22, and controls the flow rate of the raw material supplied to the reformer 22, thereby desulfurizing unit from the gas infrastructure line 6. The flow rate of the raw material supplied to 5 is controlled. In addition, the raw material supply part 4 should just be able to control the flow volume of the raw material supplied to the desulfurization part 5, and may be arrange | positioned downstream of the raw material supply part 4. FIG. In the present embodiment, the raw material supply unit 4 has a booster pump, and has a function of adjusting the flow rate of the raw material supplied to the desulfurization unit 5 by controlling, for example, input current pulses, input power, and the like. is doing.

  The operation control unit 16 is a control unit that controls the operation of the hydrogen-containing gas in the reformer 22. Here, the supply amount of the raw material supplied from the raw material supply unit 4 to the reformer 22, the water supply unit 3. Control of the amount of water supplied to the reformer 22 from the air, control of the amount of air supplied from the air supply unit 19 to the reformer 22, and control of the operation of the desulfurization connection unit 7 and the switching valves 9A and 9B I do. Further, the operation of the fuel cell 8 is also controlled (detailed explanation of the operation is omitted). The operation control unit 16 stores the operation information such as the operation sequence of the reformer 22, the raw material integrated flow rate, and the like using a semiconductor memory, a CPU, etc., calculates an appropriate operation condition according to the situation, and The operating conditions are commanded to the components required for operation of the supply unit 3, the raw material supply unit 4, the air supply unit 19, and the like.

<Operation of fuel cell system>
Next, the start-up operation of the fuel cell system 100, the operation operation during power generation, and the stop operation will be described focusing on the operation of the hydrogen generator 1.

  When the hydrogen generator 1 is started from the stopped state, the raw material is supplied from the raw material supply unit 4 to the reformer 22 through the raw material supply path 10 according to a command from the operation control unit 16. The raw material that has passed through the steam generation unit 15, the reforming unit 20, the transformation unit 13, and the selective oxidation unit 17 is supplied from the off-gas supply path 14 to the combustion unit 2 via the hydrogen gas supply path 12 and the fuel cell bypass path 23, and burned. It is ignited in the part 2 and heating of the reformer 22 is started.

  After the start of heating in the combustion unit 2, the water supply unit 3 is operated to supply water to the reformer 22, and the reforming reaction between water and the raw material is started. In the present embodiment, city gas (13A) containing methane as a main component is used as a raw material. The amount of water supplied from the water supply unit 3 is controlled so that water vapor is about 3 moles per mole of carbon atoms in the average molecular formula of city gas (S / C is about 3). Further, the air supply unit 19 is operated to supply air to the reformer 22. The amount of air supplied from the air supply unit 19 is controlled so that the amount of oxygen contained in the hydrogen-containing gas is about twice the number of moles of carbon monoxide. In the reformer 22, a steam reforming reaction is progressed in the reforming unit 20, a shift reaction is performed in the shift unit 13, and a selective oxidation reaction of carbon monoxide is advanced in the selective oxidation unit 17. At this time, based on the temperature detected by the reforming temperature detection unit 21, the combustion of the combustion unit 2 is controlled so that the reforming unit 20, the conversion unit 13, and the selective oxidation unit 17 have temperatures suitable for each reaction. To do.

  After the carbon monoxide concentration is reduced to a predetermined concentration (in this embodiment, 20 ppm or less on a dry gas basis), the switching valves 9A and 9B are operated, and the hydrogen-containing gas is supplied to the fuel cell 8 through the hydrogen gas supply path 12. By supplying the fuel cell 8, a power generation operation is performed. Further, the anode offgas discharged from the fuel cell 8 passes through the offgas supply path 14 and is supplied to the combustion unit 2. During the power generation operation, the operation control unit 16 causes the raw material supply unit 4, the water supply unit 3, the air supply unit 19, and the combustion fan 18 so that the temperature detected by the reforming temperature detection unit 21 becomes a predetermined temperature. The raw material supply amount, the water supply amount, the air supply amount, and the combustion air supply amount are controlled by controlling the operation.

When stopping the operation of the fuel cell system 100, the switching valves 9A and 9B are operated according to a command from the operation control unit 16, and the hydrogen-containing gas supplied to the fuel cell 8 is combusted through the fuel cell bypass path 23. Supply to part 2. Thereafter, the operations of the water supply unit 3, the raw material supply unit 4, and the air supply unit 19 are stopped, the supply of water, the raw material, and the air is stopped, and the operation of the hydrogen generator 1 is stopped. The hydrogen generator 1 is stopped by operating the switching valves 9A and 9B to seal the reformer 22, or the amount of the raw material corresponding to the amount of the volume of the reformer 22 that is lowered and the volume is reduced. It is preferable to carry out an operation for preventing contamination of outside air as much as possible in the reformer 22, such as an operation for supplying the air.

  Next, characteristic operations of the hydrogen generator 1 according to Embodiment 1 of the present invention will be described with reference to FIGS. 1, 2, 3, and 4.

  2, 3 and 4 are flowcharts schematically showing one cycle of characteristic operations of the hydrogen generator 1 according to Embodiment 1 of the present invention. Actually, during the power generation operation of the fuel cell system 100, for example, the operation of one cycle shown in FIGS. 2, 3, and 4 is continuously executed without being intermittent.

  Now, when the production | generation of hydrogen containing gas is started in the hydrogen production | generation apparatus 1, the operation control part 16 with which the fuel cell system 100 is provided controls the production amount of hydrogen containing gas so that the change of an electric power load may be tracked. Specifically, the raw material supply amount, the water supply amount, the air supply amount, and the combustion air supply amount are controlled by controlling the operations of the raw material supply unit 4, the water supply unit 3, the air supply unit 19, and the combustion fan 18. An amount of hydrogen-containing gas corresponding to the electric power load is generated, and the temperature detected by the reforming temperature detector 21 is controlled to a predetermined temperature.

In contrast to this operation, in the first embodiment, the follow-up control to the change in the power load is stopped (step S1), and the fixed power generation operation is performed at the power load immediately before the follow-up control is stopped. At this time, the operation control part 16 operates the raw material supply part 4, the water supply part 3, the air supply part 19, and the combustion fan 18 with the instruction value preset for every electric power load (step S2). Here, if the operation of each supply unit is normal, each supply amount 1 for each instruction value 1 is equivalent (instruction value 1 = supply amount 1). Then, to obtain the selective oxidation temperature T _P of when selective oxidation temperature detected by selective oxidation temperature detection unit 26 is stabilized. At the same time reforming temperature T _R to be detected by the reforming temperature detector 21 _obtains the shift temperature T _S that is detected by the shift temperature detection section 24 (step S3).

Then, the operation control unit 16, the selective oxidation temperature T _P is (a temperature higher than a predetermined value than the selective oxidation temperature to be expected from the indicated value 1) upper temperature limit previously set in the storage unit of the operation control unit 16 T _H or It is determined whether or not (step S4A). Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is not a pre-set the maximum temperature T _H than in the storage unit of the operation control unit 16 (NO at step S4A), selective oxidation temperature T _P Is lower than the lower limit temperature T _L (temperature lower than the selective oxidation temperature expected from each indicated value 1 by a predetermined value or more) preset in the storage unit of the operation control unit 16 (step S4B). Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P not less preset as the lower limit temperature T _L in the storage unit of the operation control unit 16 (NO in step S4B), selective oxidation temperature T _P And the reforming temperature T _R and the modification temperature T _S are acquired again.

On the other hand, the operation control unit 16, (YES at step S4A) selective oxidation temperature T _{if P} is determined to be the upper limit temperature T _H than is preset in the storage unit of the operation control unit 16, the air supply unit 19, the raw material It is determined that the supply amount 1 is not supplied with respect to at least one instruction value 1 of the supply unit 4 and the water supply unit 3 (instruction value 1 ≠ supply amount 1), and the selective oxidation temperature _TP is set to the operation control unit 16. It is determined whether or not the temperature is equal to or higher than an upper limit temperature T _HH (temperature higher than a selective oxidation temperature expected from each indicated value 1) by a predetermined value (step S5A). Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is set in advance as the upper limit temperature T _HH than in the storage unit of the operation control unit 16 (YES at step S5A), it is determined as abnormal, An alarm is output (step S6). On the other hand, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is not a pre-set the upper limit temperature T _HH than in the storage unit of the operation control unit 16 (NO at step S5A), reforming temperature T _R is or modifying the lower limit temperature T _RL0 is preset in the storage unit of the operation control section 16 and equal to or lower than the reforming upper limit temperature T _RH0 (step S7A).

If NO is determined in step S7A, it is determined that the supply amount 1 is not supplied with respect to at least one instruction value 1 of the raw material supply unit 4 and the water supply unit 3 (instruction value 1 ≠ supply amount 1). Step to flowchart A. Here, since the description will focus on the selective oxidation unit 17 and the air supply unit 19, the description of the flowchart A will be omitted. On the other hand, if it is determined YES in step S7A, determines metamorphic T _S metamorphic lower limit temperature T _{SL 0} or more and not shift the upper limit temperature T _SH0 less either be pre-set in the storage unit of the operation control section 16 ( Step S8A). If NO is determined in step S8A, it is determined that the supply amount 1 is not supplied with respect to at least one instruction value 1 of the raw material supply unit 4 and the water supply unit 3 (instruction value 1 ≠ supply amount 1). Step to flowchart B. Here, since the description will focus on the selective oxidation unit 17 and the air supply unit 19, the description of the flowchart B will be omitted.

  On the other hand, when it determines with YES by step S8A, the instruction value to the air supply part 19 is lowered | hung and air supply amount is reduced (step S9A). Here, the reduction of the air supply amount from the air supply unit 19 is executed according to preset reduction data.

Then, after the air from the air supply unit 19 is reduced in step S9A, the operation control unit 16 sets the selective oxidation temperature T _P to the upper limit temperature T _H0 (each indicated value) preset in the storage unit of the operation control unit 16. If it is determined that the temperature is not less than a predetermined oxidation temperature expected from 1) (NO in step S10A), the instruction value to the air supply unit 19 is lowered again to decrease the air supply amount (step S9A). ). On the other hand, if it is determined that the selected oxidation temperature _{T P} is equal to or less than the upper limit temperature _{T H0} set in advance in the storage unit of the operation control unit 16 (YES in step S10A), further, the selective oxidation temperature _{T P} is the operation control unit 16 It is determined whether or not the temperature is equal to or lower than a lower limit temperature T _LL preset in the storage unit (step S11A).

Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is below the lower limit temperature T _LL previously set in the storage unit of the operation control unit 16 (YES in step S11A), and determined to be abnormal, An alarm is output (step S12). On the other hand, if it is determined that the selected oxidation temperature T _P not less preset as the lower limit temperature T _LL in the storage unit of the operation control unit 16 (NO in step S11A), further, the selective oxidation temperature T _P is the operation control unit 16 It is determined whether or not the temperature is lower than the lower limit temperature T _L0 and lower than the upper limit temperature T _H0 preset in the storage unit (step S13A). Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P not more than the lower limit temperature T _L0 or more and the upper limit temperature T _H0 is preset in the storage unit of the operation control unit 16 (NO in step S13A) Then, the instruction value to the air supply unit 19 is increased, and the air supply amount is increased (step S14A).

Here, the increase in the air supply amount from the air supply unit 19 is executed in accordance with preset increase data. Then, equal to or lower than the lower limit temperature T _H0 set in advance in the storage unit of the selected oxidation temperature T _P is the operation control unit 16 again (step S10A). On the other hand, when the operation control unit 16 determines that the selective oxidation temperature _{T P} is below the lower limit temperature _{T L0} or more and the upper limit temperature _{T H0} is preset in the storage unit of the operation control unit 16 (YES in step S13A), The instruction value to the air supply unit 19 at this time is set to the new instruction value 1 for the supply amount 1 (new instruction value 1≈supply amount 1) (step S15A).

On the other hand, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is below the lower limit temperature T _L to advance is set in the storage unit of the operation control unit 16 (YES at step S4B), the air supply unit 19, the raw material It is determined that the supply amount 1 is not supplied with respect to at least one instruction value 1 of the supply unit 4 and the water supply unit 3 (instruction value 1 ≠ supply amount 1), and the selective oxidation temperature _TP is set to the operation control unit 16. It is determined whether or not the temperature is equal to or lower than a lower limit temperature T _LL (a temperature lower than the selective oxidation temperature expected from each indicated value 1 by a predetermined value or more) (step S5B).

Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is below the lower limit temperature T _LL previously set in the storage unit of the operation control unit 16 (YES at step S5B), it is determined as abnormal, An alarm is output (step S6). On the other hand, the operation control unit 16, if it is determined that the selected oxidation temperature T _P not less preset as the lower limit temperature T _LL in the storage unit of the operation control unit 16 (NO at step S5B), reforming temperature T _R is It is determined whether or not the reforming lower limit temperature _TRL0 is not less than the reforming upper limit temperature _{TRH0 and not} more than the reforming upper limit temperature _TRH0 that is preset in the storage unit of the operation control unit 16 (step S7B). If NO is determined in step S7B, it is determined that the supply amount 1 is not supplied with respect to at least one instruction value 1 of the raw material supply unit 4 and the water supply unit 3 (instruction value 1 ≠ supply amount 1). Step to flowchart A.

Here, since the description will focus on the selective oxidation unit 17 and the air supply unit 19, the description of the flowchart A will be omitted. On the other hand, if it is determined YES at step S7B, determines metamorphic T _S metamorphic lower limit temperature T _{SL 0} or more and not shift the upper limit temperature T _SH0 less either be pre-set in the storage unit of the operation control section 16 ( Step S8B). And when it determines with NO by step S8B, it determines with the supply amount 1 not being supplied with respect to the instruction value 1 of at least one of the raw material supply part 4 and the water supply part 3 (instruction value 1 ≠ supply amount 1). Step to flowchart B. Here, since the description will focus on the selective oxidation unit 17 and the air supply unit 19, the description of the flowchart B will be omitted.

  On the other hand, when it determines with YES by step S8B, the instruction value to the air supply part 19 is raised and air supply amount is increased (step S9B). Here, the increase in the air supply amount from the air supply unit 19 is executed in accordance with preset increase data.

Then, the operation control unit 16, after the air from the air supply unit 19 is increased in step S9B, preset as the lower limit temperature T _{L0 (the} instruction value in the storage unit of the selected oxidation temperature T _P is the operation control unit 16 If it is determined that the temperature is not equal to or greater than the selective oxidation temperature expected from 1) (NO in step S10B), the instruction value to the air supply unit 19 is increased again to increase the air supply amount (step S9B). ). On the other hand, if it is determined that the selective oxidation temperature _{T P} is the lower limit temperature _{T L0} or more set in advance in the storage unit of the operation control unit 16 (YES in step S10B), further, the selective oxidation temperature _{T P} is the operation control unit 16 It is determined whether or not the temperature is equal to or higher than an upper limit temperature _THH preset in the storage unit (step S11B).

Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P is set in advance as the upper limit temperature T _HH than in the storage unit of the operation control unit 16 (YES in step S11B), it is determined to be abnormal, An alarm is output (step S12). On the other hand, if it is determined that the selected oxidation temperature T _P is not a pre-set the upper limit temperature T _HH than in the storage unit of the operation control unit 16 (NO in step S11B), further, the selective oxidation temperature T _P is the operation control unit 16 It is determined whether or not the temperature is not less than the lower limit temperature T _{L0 and not} more than the upper limit temperature T _H0 preset in the storage unit (step S13B). Here, the operation control unit 16, if it is determined that the selected oxidation temperature T _P not more than the lower limit temperature T _L0 or more and the upper limit temperature T _H0 is preset in the storage unit of the operation control unit 16 (NO in step S13B) Then, the instruction value to the air supply unit 19 is lowered, and the air supply amount is reduced (step S14B).

Here, the reduction of the air supply amount from the air supply unit 19 is executed according to preset reduction data. Then, it is determined whether the re-selective oxidation temperature T _P is the lower limit temperature T _L0 or more set in advance in the storage unit of the operation control unit 16 (step S10B). On the other hand, when the operation control unit 16 determines that the selective oxidation temperature _{T P} is below the lower limit temperature _{T L0} or more and the upper limit temperature _{T H0} is preset in the storage unit of the operation control unit 16 (YES in step S13B), The instruction value to the air supply unit 19 at this time is set to a new instruction value 1 for the supply amount 1 (new instruction value 1≈supply amount 1) (step S15B).

  As described above, the hydrogen generator 1 according to the present embodiment corrects the deviation between the indicated value and the supply amount in the air supply unit 19, the raw material supply unit 4, and the water supply unit 3. The operation is different.

Here, when the raw material supply unit 4, the water supply unit 3, the air supply unit 19, and the combustion fan 18 are operated at each indicated value 1, the reforming temperature T _R , the transformation temperature T _S , and the selective oxidation temperature T _P are indicated. The reason why the temperature becomes higher or lower than the reforming temperature, the transformation temperature, and the selective oxidation temperature expected from the value 1 will be described (steps S4A and S4B).

First, when the reforming temperature T _R , the modification temperature T _S , and the selective oxidation temperature _TP are higher or lower than the reforming temperature, the modification temperature, and the selective oxidation temperature expected from the indicated value 1, the raw material supply unit 4 The supplied raw material supply amount is not supplied with respect to the raw material instruction value, the water supply amount supplied from the water supply unit 3 is not supplied with respect to the water instruction value, or is supplied from the air supply unit 19. It is conceivable that the air supply amount is not supplied to the air indication value.

  Here, in the case of the combustion fan 18, it can be confirmed from the relationship between the combustion fan voltage and the combustion fan rotational speed whether or not the combustion fan air supply amount is supplied with respect to the combustion fan air instruction value. For example, a combustion fan air flow meter may be installed on the upstream side or the downstream side of the combustion fan 18 to check whether the supply amount of the combustion fan air is supplied with respect to the combustion fan air instruction value.

  First, a case where the air supply amount supplied from the air supply unit 19 is not supplied with respect to the air indication value will be described.

  The reaction between air and carbon monoxide in the selective oxidation unit 17 is an exothermic reaction, and the calorific value depends on the air supply amount. Therefore, when the air supply amount is smaller than the air supply amount 1, the selective oxidation temperature decreases. Conversely, when the air supply amount is larger than the air supply amount 1, the selective oxidation temperature increases.

On the other hand, even if the air supply amount supplied from the air supply unit 19 is not supplied with respect to the air indication value, if the difference between the air indication value and the air supply amount is small, the reforming temperature TR _, not little effect on the temperature change of the temperature T _P. The reaction between air and carbon monoxide in the selective oxidation unit 17 is an exothermic reaction, and the temperature of the selective oxidation unit 17 slightly varies depending on the air supply amount, but the selective oxidation temperature is lower than the reforming temperature and the transformation temperature. This is because it is low enough. When the difference between the air indication value and the air supply amount is large (air indication value> air supply amount), the reaction between air and carbon monoxide is reduced in the selective oxidation unit 17 to remove carbon monoxide. This is because the fuel cell 8 is poisoned by carbon monoxide because it cannot be performed, and the power generation operation cannot be continued. When the difference between the air indication value and the air supply amount is large (air indication value <air supply amount), the reaction between the air and carbon monoxide is an exothermic reaction, so the temperature of the selective oxidation unit 17 is When the temperature rises and exceeds a certain temperature, hydrogen in the hydrogen-containing gas is methanated, and the temperature of the selective oxidation unit 17 is excessively raised. Therefore, also in this case, it is impossible to continue the operation of the hydrogen generator 1 and the power generation operation.

  Next, the raw material supply amount supplied from the raw material supply unit 4 is not supplied to the raw material instruction value, or the water supply amount supplied from the water supply unit 3 is not supplied to the water instruction value. Explain the case.

First, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1, and the water supply amount is smaller than the water supply amount 1. The reforming temperature rises. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and as the S / C is lower, the endothermic reaction does not proceed and the endothermic amount becomes smaller.

  Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was larger than the raw material supply amount 1, and the water supply amount was 1. Sometimes the reforming temperature rises. This is because the calorific value of the hydrogen-containing gas produced by the increase in the raw material supply amount increases, and the calorific value of the off gas from the fuel cell 8 increases. Further, the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the lower the S / C, the more the endothermic reaction does not proceed and the endothermic amount becomes smaller.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1 and the water supply amount is larger than the water supply amount 1. The reforming temperature decreases. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was smaller than the raw material supply amount 1, and the water supply amount was the water supply amount 1. When the reforming temperature falls. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases. Also, the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Here, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is smaller than the raw material supply amount 1, and the water supply amount is smaller than the water supply amount 1. When the amount is small, the reforming temperature does not change greatly compared to when either the raw material supply amount or the water supply amount is small. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases, but both the raw material supply amount and the water supply amount decrease. Therefore, the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst is reduced.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is larger than the raw material supply amount 1, and the water supply amount is larger than the water supply amount 1. When the amount is large, the reforming temperature does not change much compared to when either the raw material supply amount or the water supply amount is large. This is because the heat generation amount of the hydrogen-containing gas generated by the increase in the raw material supply amount increases and the heat generation amount of the off-gas from the fuel cell 8 increases, but both the raw material supply amount and the water supply amount increase. Therefore, the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst is increased.

  On the other hand, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1, and the water supply amount is smaller than the water supply amount 1. The metamorphic temperature rises. This is because the amount of water supplied to the steam generation unit 15 is reduced, so that heat exchange between the steam generation unit 15 and the shift unit 13 performed via the middle cylinder 25 is suppressed. Moreover, it is because the temperature of the reforming part 20 located upstream of the transformation part 13 rises. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and as the S / C is lower, the endothermic reaction does not proceed and the endothermic amount becomes smaller.

Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was larger than the raw material supply amount 1, and the water supply amount was 1. When the transformation temperature rises. This is because the calorific value of the hydrogen-containing gas produced by the increase in the raw material supply amount increases, and the calorific value of the off gas from the fuel cell 8 increases. Moreover, it is because the temperature of the reforming part 20 located upstream of the transformation part 13 rises. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and as the S / C is lower, the endothermic reaction does not proceed and the endothermic amount becomes smaller.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1 and the water supply amount is larger than the water supply amount 1. The metamorphic temperature decreases. This is because the amount of water supplied to the steam generation unit 15 increases, and heat exchange between the steam generation unit 15 and the shift unit 13 performed via the middle cylinder 25 is promoted. Moreover, it is because the temperature of the reforming part 20 located upstream of the transformation part 13 falls. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was smaller than the raw material supply amount 1, and the water supply amount was the water supply amount 1. When the metamorphic temperature falls. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases. Moreover, it is because the temperature of the reforming part 20 located upstream of the transformation part 13 falls. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Here, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is smaller than the raw material supply amount 1, and the water supply amount is smaller than the water supply amount 1. When the amount is small, the transformation temperature does not change significantly compared to when either the raw material supply amount or the water supply amount is small. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases, but the water supply amount supplied to the water vapor generating unit 15 decreases. This is because the heat exchange between the steam generation unit 15 and the transformation unit 13 performed via the middle cylinder 25 is suppressed. At the same time, the temperature of the reforming unit 20 located upstream of the transformation unit 13 does not drop greatly. This is because both the raw material supply amount and the water supply amount decrease, and the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst becomes small.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is larger than the raw material supply amount 1, and the water supply amount is larger than the water supply amount 1. When the amount is large, the transformation temperature does not change much compared to when either the raw material supply amount or the water supply amount is large. This is because the calorific value of the hydrogen-containing gas produced by the increase in the raw material supply amount increases and the calorific value of the off gas from the fuel cell 8 increases, but the water supply amount supplied to the water vapor generation unit 15 This is because the heat exchange between the steam generation unit 15 and the transformation unit 13 performed through the middle cylinder 25 is promoted. At the same time, the temperature of the reforming unit 20 located upstream of the transformation unit 13 decreases. This is because both the raw material supply amount and the water supply amount increase, and the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst increases.

  On the other hand, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1, and the water supply amount is smaller than the water supply amount 1. The selective oxidation temperature increases. This is because the amount of water supplied to the steam generation unit 15 is reduced, so that heat exchange between the steam generation unit 15 and the selective oxidation unit 17 performed via the middle cylinder 25 is suppressed. In addition, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 increases. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and as the S / C is lower, the endothermic reaction does not proceed and the endothermic amount becomes smaller.

Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was larger than the raw material supply amount 1, and the water supply amount was 1. When the selective oxidation temperature rises. This is because the calorific value of the hydrogen-containing gas produced by the increase in the raw material supply amount increases, and the calorific value of the off gas from the fuel cell 8 increases. In addition, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 increases. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and as the S / C is lower, the endothermic reaction does not proceed and the endothermic amount becomes smaller.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is 1 and the water supply amount is larger than the water supply amount 1. The selective oxidation temperature decreases. This is because the amount of water supplied to the steam generation unit 15 is increased, and heat exchange between the steam generation unit 15 and the selective oxidation unit 17 performed through the middle cylinder 25 is promoted. In addition, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 decreases. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Further, when the raw material supply unit 4 was operated at the raw material instruction value 1 and the water supply unit 3 was operated at the water instruction value 1, the raw material supply amount was smaller than the raw material supply amount 1, and the water supply amount was the water supply amount 1. When the selective oxidation temperature falls. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases. In addition, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 decreases. This is because the reforming reaction of the raw material and water on the reforming catalyst is an endothermic reaction, and the higher the S / C, the more the endothermic reaction proceeds and the endothermic amount increases.

  Here, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is smaller than the raw material supply amount 1, and the water supply amount is smaller than the water supply amount 1. When the amount is small, the selective oxidation temperature does not change much compared to when either the raw material supply amount or the water supply amount is small. This is because the calorific value of the hydrogen-containing gas produced by the decrease in the raw material supply amount decreases, and the calorific value of the off gas from the fuel cell 8 decreases, but the water supply amount supplied to the water vapor generating unit 15 decreases. This is because the heat exchange between the steam generation unit 15 and the selective oxidation unit 17 performed via the middle cylinder 25 is suppressed. At the same time, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 does not drop greatly. This is because both the raw material supply amount and the water supply amount decrease, and the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst becomes small.

  Conversely, when the raw material supply unit 4 is operated at the raw material instruction value 1 and the water supply unit 3 is operated at the water instruction value 1, the raw material supply amount is larger than the raw material supply amount 1, and the water supply amount is larger than the water supply amount 1. When the amount is large, the selective oxidation temperature does not change much compared to when either the raw material supply amount or the water supply amount is large. This is because the calorific value of the hydrogen-containing gas produced by the increase in the raw material supply amount increases and the calorific value of the off gas from the fuel cell 8 increases, but the water supply amount supplied to the water vapor generation unit 15 This is because the heat exchange between the steam generation unit 15 and the selective oxidation unit 17 performed through the middle cylinder 25 is promoted. At the same time, the temperature of the reforming unit 20 located upstream of the selective oxidation unit 17 decreases. This is because both the raw material supply amount and the water supply amount increase, and the endothermic amount in the endothermic reaction between the raw material and water on the reforming catalyst increases.

In the first embodiment, the upper limit values of the selective oxidation temperature T _P , the reforming temperature T _R , and the transformation temperature T _S are T _H , T _HH , T _H0 , T _RH0 , T _SH0 , and the lower limit value is T _L. Although T _LL , T _L0 , T _RL0 , and T _SL0 are used, for example, the air supply unit 19, the raw material supply unit 4, the water supply unit 3, and the combustion fan 18 are operated at each indicated value 1, and the air supply unit 19. When the indicated value (supply amount) of at least one of the raw material supply unit 4 and the water supply unit 3 is shifted, the selective oxidation unit (overheating), the fuel cell (poisoning), the amount of hydrogen in the hydrogen-containing gas, Carbon monoxide concentration, or reforming section 20 and metamorphic section 13
In addition, an air instruction value, a raw material instruction value, and a water instruction value that may cause problems such as a decrease in power generation efficiency in each catalyst of the selective oxidation unit 17 or the structure of the reformer 22 are calculated in advance through experiments, simulations, and the like. In addition, the air supply unit 19, the raw material supply unit 4, and the water supply unit 3 are operated at the air indication value, the raw material indication value, the water indication value, and the combustion fan 18 at the indication value 1, and the selective oxidation temperature when stabilized. The reforming temperature and the modification temperature may be set as the upper limit value and the lower limit value.

Next, when the raw material supply unit 4, the water supply unit 3, the air supply unit 19, and the combustion fan 18 are operated at each indicated value 1, the selective oxidation temperature _TP is higher than the selective oxidation temperature expected from the indicated value 1. When (T _P ≧ T _HH ) or low (T _P ≦ T _LL ), it is determined that there is an abnormality and the reason for outputting an alarm will be described (steps S5A and S5B).

First, the raw material supply section 4, the water supply unit 3, the air supply unit 19, when the combustion fan 18 is operated at the indicated value 1 is higher than the selected oxidation temperature in which the selective oxidation temperature T _P is predicted from the indicated value 1 (T _P ≧ T _HH) is a case, as described above, it is considered the difference between the air indicated value and the air supply amount is a large amount (air indicated value <air supply amount), optionally, selective oxidation This is because the temperature of the unit 17 is excessively increased, and the operation of the hydrogen generator 1 and the continuation of the power generation operation are impossible.

On the other hand, the raw material supply section 4, the water supply unit 3, the air supply unit 19, when the combustion fan 18 is operated at the indicated value 1, metamorphic T _P is lower than the metamorphic temperature expected from the indicated value of 1 (T _P ≦ T _LL ), but as described above, the difference between the air indication value and the air supply amount is considered to be large (air indication value> air supply amount). This is because the fuel cell 8 is poisoned by carbon monoxide and cannot be continuously operated.

When the alarm is output, the operation of the fuel cell 8 and the hydrogen generator 1 may be stopped. In addition, the service maintenance company and the fuel cell 8 at the customer's house may be connected online, and the service maintenance company may be notified when an alarm is output. In addition, by setting some upper limit value _THH and lower limit value _TLL for the selective oxidation temperature, if there is a slight abnormality, continuous operation is performed until the service person obtains the failed part and goes to the customer's home. May be. Of course, safety is ensured because continuous operation is performed after monitoring the abnormality. In addition, although step S5A and step 5B were demonstrated here, step S11A and step 11B are the same reasons.

Next, when the raw material supply unit 4, the water supply unit 3, the air supply unit 19, and the combustion fan 18 are operated at each indicated value 1, the selective oxidation temperature _TP is higher than the selective oxidation temperature expected from the indicated value 1. when made, lowering the selective oxidation instruction value, when the selective oxidation temperature T _P is lower than the selected oxidation temperature to be expected from the indicated value 1, it explains why increasing the selective oxidation instruction value (step S9A, step S9B).

First, when the selective oxidation temperature _TP is higher than the selective oxidation temperature expected from the indicated value 1, it is considered that the air supply amount is larger than the air supply amount 1 as described above. Therefore, the air supply amount is reduced by lowering the air instruction value. At this time, the selective oxidation temperature simultaneously decreases. Conversely, when the selective oxidation temperature _TP is lower than the selective oxidation temperature expected from the indicated value 1, it is conceivable that the air supply amount is smaller than the air supply amount 1 as described above. Therefore, the air supply amount is increased by increasing the air instruction value. At this time, the selective oxidation temperature rises at the same time.

The selective oxidation temperature is within a selective oxidation temperature range that can prevent overheating of the selective oxidation section set in advance, poisoning of the fuel cell by carbon monoxide, and further failure of the fuel cell system. there _{T L0 ≦ T P ≦ T H0} ( step S13A, step S13B) the air indicated value when it reaches the newly set as a new air instruction value 1 for air supply amount 1 (
By step S15A and step S15B), the deviation | shift of the air supply amount with respect to an air instruction | indication value can be correct | amended to a value equivalent to a normal value or a value close | similar to it.

  As a result, a certain amount of hydrogen and hydrogen with a low carbon monoxide concentration can be generated. In addition, it is possible to prevent overheating of the selective oxidation unit, poisoning of the fuel cell due to carbon monoxide, and failure of the fuel cell system.

  In the first embodiment, the reforming temperature detection unit 21 or the transformation temperature detection unit 24 is provided, but the reforming detected by the reforming temperature detection unit 21 even when sensorlessness is advanced in the future. Based on either the temperature or the transformation temperature detected by the transformation temperature detection unit 24, it is determined whether the raw material supply amount and the water supply amount from the raw material supply unit 4 and the water supply unit 3 are appropriate, and the raw material indication value It is possible to correct the raw material supply amount corresponding to the water supply amount and the water supply amount corresponding to the water indication value, or determine whether the raw material supply amount from the raw material supply unit 4 and the water supply unit 3 and the water supply amount are abnormal. However, since an alarm can be output to the outside, it is possible to generate a certain amount of hydrogen and hydrogen with a low carbon monoxide concentration, and it is possible to prevent failure of the hydrogen generator. Absent.

  The present invention can determine whether the air supply amount supplied from the air supply unit to the hydrogen generator is appropriate, and can correct the air supply amount corresponding to the air indication value. Hydrogen with a low carbon oxide concentration can be produced. In addition, it is possible to judge whether or not the amount of air supplied from the air supply unit to the hydrogen generator is abnormal, and to output an alarm to the outside, overheating of the selective oxidation unit, or a fuel cell using carbon monoxide Poisoning and further failure of the fuel cell system can be prevented. Furthermore, an air flow rate measuring means such as a flow meter is not required, which is useful for a fuel cell system capable of reducing costs.

DESCRIPTION OF SYMBOLS 1 Hydrogen generator 2 Combustion part 3 Water supply part 4 Raw material supply part 5 Desulfurization part 6 Gas infrastructure line 7 Desulfurization connection part 8 Fuel cell 9A, 9B Switching valve 10 Raw material supply path 11 Inner cylinder 12 Hydrogen gas supply path 13 Metamorphic part 14 Off-gas supply path 15 Water vapor generation section 16 Operation control section 17 Selective oxidation section 18 Combustion fan 19 Air supply section 20 Reforming section 21 Reforming temperature detection section 22 Reformer 23 Fuel cell bypass path 24 Transformation temperature detection section 25 Middle cylinder 26 Selective oxidation temperature detector 100 Fuel cell system

Claims (4)

A reforming unit that is supplied with raw material and water and generates a hydrogen-containing gas by a reforming reaction;
A reforming temperature detection unit for detecting the temperature of the reforming unit;
A raw material supply unit that supplies the reforming unit with a raw material according to a raw material supply amount instruction value;
A water supply unit for supplying water according to a water supply amount instruction value to the reforming unit;
A metamorphic section that reduces the concentration of carbon monoxide in the hydrogen-containing gas produced by the reforming section;
A transformation temperature detection unit for detecting the temperature of the transformation unit;
A selective oxidation unit that further reduces the concentration of carbon monoxide in the hydrogen-containing gas reduced by the shift unit;
An air supply unit for supplying air according to an air supply amount instruction value to the selective oxidation unit;
A selective oxidation temperature detection unit for detecting a temperature of the selective oxidation unit;
A fuel cell that generates power by supplying the hydrogen-containing gas and the oxygen-containing gas with a reduced carbon monoxide concentration in the selective oxidation unit, and that generates power following a change in a power load of a power supply destination; and
Of the hydrogen-containing gas whose carbon monoxide concentration is reduced in the selective oxidation unit, the remaining hydrogen-containing gas that has not been consumed in the fuel cell is burned to generate heat necessary for the reforming reaction of the reforming unit. A combustion section to supply;
An operation control unit that outputs the air supply amount instruction value to the air supply unit based on the selective oxidation temperature detected by the selective oxidation temperature detection unit;
The operation control unit operates the fuel cell without following a change in power load for a preset period after generating an arbitrary power generation amount of the fuel cell, and the air supply unit is preset. If the temperature difference between the predicted selective oxidation temperature expected from the indicated value and the detected selective oxidation temperature detected by the selective oxidation temperature detecting unit is greater than or equal to a predetermined temperature difference, the instruction is set in advance. A fuel cell system that determines that the air corresponding to the value is not supplied as instructed from the air supply unit. The operation controller is
When the temperature difference between the expected selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than a predetermined temperature difference,
When the detected selective oxidation temperature is higher than the expected selective oxidation temperature, it is determined that a large amount of air corresponding to a preset instruction value is supplied from the air supply unit,
2. The fuel cell system according to claim 1, wherein when the detected selective oxidation temperature is lower than the expected selective oxidation temperature, it is determined that a small amount of air corresponding to a preset instruction value is supplied from the air supply unit. The operation controller is
When the temperature difference between the expected selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than a predetermined temperature difference,
If the detected selective oxidation temperature is higher than the expected selective oxidation temperature, control to reduce the indicated value to the air supply unit,
2. The fuel cell system according to claim 1, wherein when the detected selective oxidation temperature is lower than the expected selective oxidation temperature, control is performed so as to increase an instruction value to the air supply unit. The operation controller is
When the temperature difference between the expected selective oxidation temperature and the detected selective oxidation temperature is equal to or greater than the predetermined temperature difference,
The fuel cell system according to any one of claims 1 to 3, wherein the air supply amount from the air supply unit is determined to be abnormal and an alarm is output.