JP2006040607A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a fuel cell from being damaged when the generated output required for the fuel cell is increased. <P>SOLUTION: The fuel cell system, comprising a reformer (1) which makes fuel as a raw material and water vapor reacted to produce reformed gas containing hydrogen, the fuel cell 7 generating electricity by the reformed gas produced with the reformer (1), and a power converter 11 which supplies a load with the generated output of the fuel cell 7, comprises a control means (14) which increases the amount of the raw material to be supplied to the reformer (1) according to the increased amount of the generated output required for the fuel cell 7, operates a timer, and after completion of the timer, outputs a signal permitting the power converters 11 to increase the generated output. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell system, and more particularly to control of a fuel cell system that generates power using a polymer electrolyte fuel cell.

  A fuel cell system includes, for example, a reformer that produces hydrogen by reacting a hydrocarbon-based fuel that is a raw material with water, a fuel cell that generates electricity by reacting hydrogen and oxygen, and a power converter (inverter). And, if necessary, an auxiliary combustor for burning the anode exhaust gas discharged from the anode of the fuel cell.

  In the presence of a catalyst, the reformer is, for example, a reformer that reacts a hydrocarbon-based fuel with steam to reform hydrogen, and CO in the reformed gas generated from the reformer is converted by CO shift reaction. A CO converter for oxidizing and a CO selective oxidizer for selectively oxidizing CO remaining in the reformed gas are provided. The reformed gas generated by such a reforming reactor is introduced into the anode of the fuel cell and reacts with oxygen introduced into the cathode to generate electricity.

  On the other hand, the anode exhaust gas of the fuel cell contains unreacted hydrogen that is not used for power generation. For this reason, the anode exhaust gas is used for preheating the raw material supplied to the reforming reactor, heating the reformer, or the like by introducing it into the auxiliary combustor and burning it. In addition, a method of introducing hot water obtained by recovering waste heat from a reformer or a fuel cell to a hot water storage tank and using it as hot water is being studied.

  In such a fuel cell system, there has been reported a fuel cell control method for increasing the amount of raw material supplied to the reformer as the generated power required for the fuel cell increases (see Patent Document 1). ). According to this, in consideration of the delay time until the raw material introduced into the reformer is actually supplied to the fuel cell, and considering the power generation efficiency of the fuel cell, the voltage of the fuel cell is less than the delay time. It has been proposed to adjust the time constant related to the increase control of the output current of the inverter provided between the fuel cell and the load so as to be kept constant for a slightly longer period.

JP-A-3-81968

  However, although the invention described in Patent Document 1 suppresses an increase in the output current of the inverter, since the output current of the inverter is increased with an increase in the required generated power, the power generation efficiency of the fuel cell is reduced. If the rate of increase or the amount of increase in load power is large, the amount of hydrogen in the reformed gas will not increase in time, and the fuel cell may be damaged.

  An object of the present invention is to prevent the fuel cell from being damaged when the generated power required for the fuel cell is increased.

  In order to solve the above-mentioned problems, the present invention generates a reformed gas containing hydrogen by reacting a raw material fuel and water vapor, and generates power using the reformed gas generated by the reformer. In a fuel cell system including a fuel cell and a power converter that supplies power generated by the fuel cell to a load, the amount of raw material supplied to the reformer is determined based on the amount of increase in power generated required for the fuel cell. And a control means for operating the timer and outputting an output signal allowing the increase in the generated power to the power converter after the timer operation ends.

  That is, as the demand for generated power increases, the amount of reformed gas, that is, hydrogen supplied to the anode of the fuel cell increases when a predetermined time elapses after the amount of raw material supplied to the reformer is increased. As a result, the generated voltage of the fuel cell increases, and damage to the fuel cell can be prevented even if the output current of the power converter is increased.

  In this case, the timer is preferably set to be equal to or greater than the time difference until the raw material supplied to the reformer is reformed into hydrogen and reaches the anode outlet of the fuel cell. By providing this time difference, the anode is supplied with an amount of hydrogen necessary to generate electric power according to the load, so that damage to the fuel cell can be prevented.

  The fuel cell system includes an auxiliary combustor that captures and combusts anode exhaust gas discharged from the anode of the fuel cell, and the control means determines the anode exhaust gas from the amount of raw material supplied to the reformer and the output value of the fuel cell. By calculating the amount of hydrogen therein and controlling the amount of air supplied to the auxiliary combustor based on this amount of hydrogen, the combustion temperature of the auxiliary combustor can be stabilized.

  The auxiliary combustor burns the anode exhaust gas and preheats the raw material supplied to the reformer, and calculates the preheat temperature of the raw material from the amount of raw material supplied to the reformer and the output value of the fuel cell. Based on this preheating temperature, at least one of the amount of fuel for auxiliary combustion supplied to the auxiliary combustor or the amount of combustion air supplied to the reformer may be controlled. According to this, since the combustion temperature of the auxiliary combustor or the reforming temperature of the reformer can be maintained and controlled at a predetermined temperature, the reforming efficiency of the raw material is stabilized, and the efficiency of the entire fuel cell system can be improved.

  According to the present invention, it is possible to realize a fuel cell system that does not damage the fuel cell when the generated power required for the fuel cell is increased.

(First embodiment)
Hereinafter, a first embodiment of a fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a configuration diagram of a fuel cell system to which the present invention is applied. FIG. 2 is a flowchart showing a control procedure to which the present invention is applied. FIG. 3 is a diagram showing how the output power and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied.

  As shown in FIG. 1, the fuel cell system of the present embodiment includes a reformer 1, a CO converter 3, a CO selective oxidizer 5, a fuel cell 7, an auxiliary combustor 9, an inverter 11, and a control device 14. Composed.

  The reformer 1 has a vertical container, and an auxiliary combustor 9 is disposed on the outer wall of the container. A hydrocarbon-based fuel such as city gas (hereinafter abbreviated as city gas) and water vapor supplied to the reformer 1 are preheated by the auxiliary combustor 9. The reformer 1 employs a partial oxidation method, and includes a combustion catalyst layer that partially burns city gas with air, and a reforming catalyst layer that reforms city gas by reacting water vapor.

  As the reforming catalyst layer, for example, a Ni-based or Ru-based reforming catalyst is used, and a city gas and water vapor react to generate a hydrogen-rich reformed gas. In the case of city gas containing a mercaptan-based odorant or the like, for example, a Ni-based reforming catalyst is used to prevent catalyst poisoning by sulfur. In order to prevent carbon deposition, it is preferable to add an alkali metal, an alkaline earth metal, a rare earth metal, or the like to the catalyst. In the present embodiment, city gas is used as the hydrocarbon-based fuel of the reformer 1. However, for example, natural gas, methane gas, propane gas, methanol, naphtha, gasoline, kerosene, dimethyl ether, or the like may be used.

The outlet side of the reformer 1 is connected to the inlet side of the heat exchanger 13. In the heat exchanger 13, the high-temperature reformed gas discharged from the reformer 1 is cooled by exchanging heat with water discharged from the water pump 15. The reformed gas cooled by the heat exchanger 13 is guided to the inlet side of the CO converter 3. The CO converter 3 is provided with a CO shift catalyst layer, and CO in the reformed gas reacts with water vapor by the CO shift reaction and is converted to CO ₂ . As the CO shift catalyst, for example, a transition metal system such as Cu—Zn or a noble metal system such as Pt or Ru can be used, but it is preferable to use a noble metal system in terms of safety, reaction heat, and the like.

The outlet side of the CO transformer 3 is connected to the inlet side of the heat exchanger 17. In the heat exchanger 17, the reformed gas discharged from the CO converter 3 is cooled by exchanging heat with the water discharged from the water pump 19. The reformed gas cooled by the heat exchanger 17 is guided to the inlet side of the CO selective oxidizer 5. The CO selective oxidizer 5 includes a CO selective oxidation catalyst layer, and CO in the reformed gas is selectively oxidized and converted to CO ₂ . On the other hand, the CO selective oxidation catalyst layer is supplied with cooling water discharged from the water pump 21 through a heat transfer tube, and is maintained at a predetermined catalyst activation temperature. In this CO selective oxidation catalyst layer, for example, a catalyst carrier such as γ-alumina, titania, cordierite honeycomb, paper honeycomb or the like, transition metal such as Mn or Mg which is an active component of the catalyst, or Pt, Ru, Pd or the like What carried the noble metal is used.

  The fuel cell 7 is, for example, an internal humidification type polymer electrolyte fuel cell, and includes an electrolyte, an anode 23 (fuel electrode) disposed with the electrolyte sandwiched therebetween, and a cathode 25 (oxygen electrode). ing. The electric power generated by the electrode reaction between the anode 23 and the cathode 25 is converted into electric power for household electric appliances serving as a load via an inverter 11 connected to the fuel cell 7. On the other hand, the heat generated by the electrode reaction is recovered as the battery exhaust heat through the cooling water that cools the battery body together with the latent heat of the condensed water. The heat-recovered water is stored in a hot water tank (not shown) and used as hot water.

  Gas containing hydrogen that has not been used for power generation is discharged from the outlet side of the anode 23 as anode exhaust gas, and then supplied to the inlet side of the auxiliary combustor 9 equipped with a combustion catalyst, a burner, and the like through the pipe 27. It is used as a fuel for combustion. Air or oxygen is supplied to the inlet side of the cathode 25 via a pipe 29, and the cathode exhaust gas is discharged to the atmosphere via a pipe 31 from the outlet side.

  Next, the configuration of the city gas, water vapor, and air supply system will be described. A city gas supply pipe 33, an air supply pipe 35, and a water supply pipe 37 are connected to the reformer 1, respectively. In the city gas supply pipe 33, a desulfurizer 39 that removes odorant (sulfur component) contained in the city gas along the gas flow direction, and a gas booster 41 that compresses the desulfurized city gas to a high pressure. Are sequentially arranged, and the city gas discharged from the gas booster 41 is preheated through the auxiliary combustor 9 and then supplied into the reformer 1.

  The water supply pipe 37 is branched and connected to the suction ports of the water pumps 15, 19, 21 and 43. The discharge sides of the water pumps 15, 19 and 21 are connected to the reformer 1 via the heat exchangers 13 and 17 and the CO selective oxidizer 5, respectively, while the discharge side of the water pump 43 is branched from the piping. Then, after being connected to the city gas supply pipe 33 and the air supply pipe 35, they are connected to the reformer 1 via the auxiliary combustor 9.

  The air supply pipe 35 is branched and connected to the suction ports of the air blowers 24, 45, and 47, respectively. The discharge side of the air blower 24 is connected to the inlet side of the CO selective oxidizer 5 through a pipe 48 so as to supply oxidization air. The discharge side of the air blower 45 is connected to the auxiliary combustor 9 and supplies combustion air, while the discharge side of the air blower 47 uses the inside of the auxiliary combustor 9 as a piping path and then joins the city gas supply pipe 33. After that, it is connected to the reformer 1, and the air preheated via the auxiliary combustor 9 is mixed with the city gas and supplied to the reformer 1.

  Next, the configuration of the control system of the fuel cell system will be described. The control device 14 is electrically connected to the inverter 11, the city gas control system, the air control system, and the water control system. The control device 14 outputs a command to the inverter 11 based on the increase / decrease in the power usage amount on the user side, and the inverter 11 that receives the command controls the power taken out from the fuel cell 7. In addition, the control device 14 controls the gas booster 41 of the city gas control system, and controls the air blower 47 of the air control system to adjust the supply pressures of the city gas and air, respectively, to match the generated electric energy. The amount of generated hydrogen is controlled. Similarly, the control device 14 controls the water pumps 15, 19, 21, 43 of the water control system, adjusts the amount of water supplied to the reformer 1 and the CO selective oxidizer 5, and controls the amount of generated hydrogen. It is like that.

  Next, the operation of this embodiment will be described. First, the case where the power demand on the user side as a load increases will be described. When the amount of electric power required from the load is transmitted to the control device 14, the generation from the control device 14 to the city gas control system, air control system and water control system of the fuel cell system increases the amount of hydrogen based on the required power. A hydrogen amount increase command is output, and then an output power increase command is output to the inverter 11 based on the required power amount.

  Here, when the power generation output of the fuel cell 7 is increased after increasing the supply amount of the raw material supplied to the reformer 1, that is, the city gas and the steam, if the increase rate or increase amount of the required power is large, The increase in the amount of hydrogen in the reformed gas is not in time, the amount of hydrogen is insufficient, and the fuel cell 7 may be damaged.

  For this reason, in this embodiment, a difference is provided in the time for outputting the generated hydrogen amount increase command and the output power increase command, and this difference is used to reform the raw material supplied to the reformer 1 into hydrogen so that the fuel cell 7 Control is performed using a timer so that the time required for reaching the outlet of the anode 23 is reached. Specifically, as shown in FIG. 2 and FIG. 3, when the power demand on the user side increases, the control device 14 outputs a generated hydrogen amount increase command, and the gas booster 41, each water pump and each air blower. And the timer operation is started, and when the timer operation ends when a predetermined time elapses, an output power increase command is output and the output current of the inverter 11 is increased, whereby the fuel cell 11 It is controlled to increase the generated power.

  Here, the set time of the timer is determined, for example, by obtaining in advance the time required for the increased hydrogen to reach the outlet of the anode 23 after a command to increase the amount of generated hydrogen is output, and setting this time as a reference. It is preferable. That is, normally, a time longer than the reference time is set. However, if the set time becomes too long, the amount of hydrogen required for the required power is excessively supplied and the amount of hydrogen in the anode exhaust gas increases, which is uneconomical. It becomes. The anode exhaust gas discharged from the anode 23 of the fuel cell 7 is guided to the auxiliary combustor 9 for combustion treatment and used for preheating raw materials and water before being supplied to the reformer 1.

  For example, when the fuel cell system of this embodiment is used as a small power generation system for home use, since the flow rate of raw materials and the like is small, versatile auxiliary equipment (such as an air valve and a gas booster) can be used at a rated output. If used, the pressure loss at the time of restricting the flow rate becomes large. Therefore, it is preferable to simply adjust the flow rate by, for example, pulse control instead of the pressure adjustment by these auxiliary machines.

  According to the present embodiment, since the hydrogen concentration of the reformed gas supplied to the anode 23 is increased to a predetermined amount and the output of the inverter 11 is increased to the required power of the load, the fuel cell 7 is damaged. There is nothing.

(Second Embodiment)
Next, a second embodiment of the fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 4 is a flowchart showing a control procedure to which the present invention is applied. FIG. 5 is a diagram showing how the output and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied. In the present embodiment, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, in the air control system of FIG. 1, in accordance with a command from the control device 14, in addition to controlling the amount of air for partial combustion of the reformer 1 by the air blower 47, the output of the air blower 45 is adjusted, The difference from the first embodiment is that the amount of combustion air in the auxiliary combustor 9 is controlled.

  The operation of this embodiment will be described with reference to FIGS. First, when the power demand on the user side increases, the control device 14 outputs an instruction to increase the amount of generated hydrogen, increases the output of the gas booster 41, each water pump, each air blower, etc. and starts the timer operation. To do. Then, a set time, for example, a time required for the increased hydrogen to reach the outlet of the anode 23 after a command to increase the amount of generated hydrogen has passed, and at the same time the first timer operation ends, A power increase command is output, and the power generated by the fuel cell 11 is increased. Subsequently, when a predetermined time elapses after the first timer operation ends, the second timer operation ends. At the end of the second timer operation, a combustion air amount increase command for increasing the output of the air blower 45 is output, and the amount of combustion air supplied to the auxiliary combustor 9 increases. That is, when the command to increase the amount of generated hydrogen is output and the amount of hydrogen increases, the amount of hydrogen in the anode exhaust gas also increases. Therefore, the amount of combustion air in the auxiliary combustor 9 is increased by this increased amount of hydrogen. Control.

  Here, the control by the second timer operation that is an increase command of the combustion air amount may be performed simultaneously with the increase command of the generated hydrogen amount at which the timer operation starts, or after the first timer operation ends, Control may be performed with a time difference shorter than the required time until the gas component after the command to increase the amount of generated hydrogen is discharged from the anode 23 and reaches the inlet of the auxiliary combustor 9.

  According to the present embodiment, as in the first embodiment, after increasing the hydrogen concentration of the reformed gas supplied to the anode 23 to a predetermined amount, the output power of the inverter 11 is increased to the required power of the load. Therefore, in addition to preventing the fuel cell 7 from being damaged, hydrogen in the anode exhaust gas can be combusted satisfactorily, so that the preheating temperature of the raw material can be stabilized and the heat recovery efficiency can be improved.

(Third embodiment)
Next, a third embodiment of the fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 6 is a flowchart showing a control procedure to which the present invention is applied. FIG. 7 is a diagram showing how the output and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied. In the present embodiment, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, in the control system of FIG. 1, the fuel cell 7 and the control device 14 are directly electrically connected, the output current of the fuel cell 7 is input to the control device 14, and the calculated amount of hydrogen in the anode exhaust gas is calculated. Is different from the first embodiment in that the output of the air blower 45 is controlled.

  The operation of this embodiment will be described with reference to FIGS. First, when the power demand on the user side increases, the control device 14 outputs an instruction to increase the amount of generated hydrogen, increases the output of the gas booster 41, each water pump, each air blower, etc. and starts the timer operation. To do. When the set time elapses and the timer operation ends, the control device 14 outputs an output power increase command to the inverter 11 to increase the generated power of the fuel cell 11.

  Next, when the value of the output current of the fuel cell 7 is input to the control device 14, the amount of hydrogen in the anode exhaust gas is calculated from this value and the amount of feedstock supplied to the reformer 1. Based on the amount, for example, the controller 14 outputs a combustion air amount increase command for increasing the output of the air blower 45, and controls the combustion state of the anode exhaust gas. That is, since the amount of hydrogen consumed in the fuel cell 7 is proportional to the output current of the fuel cell 7, the amount of hydrogen in the anode exhaust gas is calculated from the supply amount of the raw material for generating hydrogen and the output current of the fuel cell 7. The amount of combustion air is adjusted based on this value.

  According to this embodiment, as in the first embodiment, in addition to preventing damage to the fuel cell 7, an appropriate air amount can be supplied to the auxiliary combustor 9 based on the amount of hydrogen in the anode exhaust gas. A good combustion state of the exhaust gas can be obtained, the preheating temperature of the raw material can be further stabilized, and the heat recovery efficiency can be improved.

  Further, by controlling the outputs of other air blowers, gas boosters 41 and water pumps as auxiliary devices other than the air blower 45 based on the calculated hydrogen amount value, the reforming efficiency is improved and the fuel is increased. The efficiency of the entire battery system can be improved.

(Fourth embodiment)
Next, a fourth embodiment of a fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 8 is a flowchart showing a control procedure to which the present invention is applied. FIG. 9 is a diagram showing how the output power and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied. In the present embodiment, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, in the control system of FIG. 1, the value of the output current of the fuel cell 7 is input to the control device 14, and the flow rate value of the city gas from the gas booster 41 is input to the control device 14 as the amount of feedstock. The raw material preheating temperature is obtained from the calculated amount of hydrogen in the anode exhaust gas, and the output of the air blower 47 is controlled by this preheating temperature, which is different from the first embodiment.

  The operation of this embodiment will be described with reference to FIGS. First, based on an increase in power demand on the user side, the control device 14 outputs an instruction to increase the amount of generated hydrogen, and until the generated power of the fuel cell 11 is increased by timer control, the same as in the third embodiment. Control is performed. Next, when the output (flow rate value) of the gas booster 41 together with the output current of the fuel cell 7 is input to the control device 14, the amount of hydrogen in the anode exhaust gas is calculated from these values. Here, the combustion heat of the anode exhaust gas is used for preheating the raw material, and this preheating temperature (heat generation amount) is calculated from the amount of hydrogen in the anode exhaust gas, so the preheat temperature calculated thereby and the reformer 1 The air ratio for adjusting to a predetermined reforming temperature is determined from the amount of city gas supplied to the gas, that is, the flow rate value of the gas booster 41. Based on this air ratio, the controller 14 outputs a partial oxidation air amount change command to the air blower 47.

  According to the present embodiment, as in the first embodiment, in addition to preventing damage to the fuel cell 7, by increasing or decreasing the amount of partial oxidation air based on the raw material preheating temperature, the reforming catalyst layer Since the temperature can be maintained and controlled within an appropriate temperature range, the reforming efficiency can be further stabilized.

(Fifth embodiment)
Next, a fifth embodiment of the fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 10 is a flowchart showing a control procedure to which the present invention is applied. FIG. 11 is a diagram showing how the output and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied. In the present embodiment, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, first, as described in the fourth embodiment, the value of the output current of the fuel cell 7 and the output value of the gas booster 41 are input to the control device 14 to obtain the raw material preheating temperature. In FIG. 1, for example, an auxiliary combustion fuel blower is disposed in a pipe branched from the city gas supply pipe 33 on the front side of the gas booster 41, and an auxiliary combustion blower is supplied from the auxiliary combustion fuel blower to the auxiliary combustor 9. City gas is supplied.

  In this embodiment, as shown in FIG. 10 and FIG. 11, instead of outputting a partial oxidation air amount change command to the air blower 47, the control device 14 determines the auxiliary combustion fuel based on the raw material preheating temperature. This is different from the fourth embodiment in that an auxiliary combustion fuel change command is output to the blower.

  According to the present embodiment, as in the first embodiment, in addition to preventing damage to the fuel cell 7, when the raw material preheating temperature is lowered due to operating conditions, the auxiliary fuel is supplied to thereby reduce the raw material preheating temperature. It can be maintained and controlled above a predetermined temperature.

(Sixth embodiment)
Next, a sixth embodiment of the fuel cell system to which the present invention is applied will be described with reference to the drawings. FIG. 12 is a flowchart showing a control procedure to which the present invention is applied. FIG. 13 is a diagram showing how the output and the power generation amount change with time in the control of the fuel cell system to which the present invention is applied. In the present embodiment, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  The fuel cell system of the present embodiment includes, for example, control when the power demand decreases in addition to the first embodiment corresponding to the case where the power demand on the user side increases. Hereinafter, control when the power demand decreases will be described.

  As shown in FIGS. 12 and 13, when a power reduction request is transmitted to the control device 14, first, an output power reduction command for reducing the generated power of the fuel cell 7 is output to the inverter 11 based on the required power. At the same time, the timer starts to operate. Then, when the first timer operation is completed, based on the required power, an instruction to reduce the amount of generated hydrogen is issued from the control device 14 to the city gas control system, air control system, and water control system of the fuel cell system. Then, when the second timer operation ends, a combustion air amount decrease command for decreasing the output of the air blower 45 is output, and the combustion air amount supplied to the auxiliary combustor 9 decreases. Here, as described above, the reduction command of the generated hydrogen amount is output to the gas booster 41 of the city gas control system, each air blower of the air control system, and each water pump of the water control system. Is done.

  The timer control of the generated hydrogen amount reduction command may be after the output power reduction command at which the timer operation starts, but is preferably simultaneous. Further, the command for reducing the amount of combustion air at the end of the second timer is such that the gas component after the command for reducing the amount of generated hydrogen is discharged from the anode 23 after the end of the first timer and is supplied to the inlet of the auxiliary combustor 9. It is preferable to set with a time difference shorter than the required time to reach.

  According to this embodiment, the control of the reformer 1 and the fuel cell 7 can be controlled in accordance with the change in the power demand on the user side, and the construction of the fuel cell system in accordance with the actual operation can be achieved. .

It is a block diagram of a fuel cell system to which the present invention is applied. It is a flowchart which shows the procedure of control of the 1st Embodiment of this invention. It is a figure which shows a mode that an output and electric power generation amount change with time in control of the fuel cell system of the 1st Embodiment of this invention. It is a flowchart which shows the procedure of control of the 2nd Embodiment of this invention. It is a figure which shows a mode that an output and electric power generation amount change with time in control of the fuel cell system of the 2nd Embodiment of this invention. It is a flowchart which shows the procedure of control of the 3rd Embodiment of this invention. It is a figure which shows a mode that an output and electric power generation amount change with time in control of the fuel cell system of the 3rd Embodiment of this invention. It is a flowchart which shows the procedure of control of the 4th Embodiment of this invention. It is a figure which shows a mode that an output and the electric power generation amount change with time in control of the fuel cell system of the 4th Embodiment of this invention. It is a flowchart which shows the procedure of control of the 5th Embodiment of this invention. It is a figure which shows a mode that an output and the electric power generation amount change with time in control of the fuel cell system of the 5th Embodiment of this invention. It is a flowchart which shows the procedure of control of the 6th Embodiment of this invention. It is a figure which shows a mode that an output and the electric power generation amount change with time in control of the fuel cell system of the 6th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reformer 7 Fuel cell 9 Auxiliary combustor 11 Inverter 14 Control device 15, 19, 43 Water pump 23 Anode 24, 45, 47 Air blower 33 City gas supply piping 35 Air supply piping 37 Water supply piping

Claims (3)

A reformer that generates a reformed gas containing hydrogen by reacting a raw material fuel with water vapor, a fuel cell that generates electric power using the reformed gas generated by the reformer, and generated power of the fuel cell In a fuel cell system comprising a power converter that supplies a load to a load, the amount of raw material supplied to the reformer is increased based on the amount of increase in generated power required for the fuel cell, and a timer is operated, A fuel cell system comprising: control means for outputting a signal allowing the increase of the generated power to the power converter after the operation of the timer ends. An auxiliary combustor that takes in and discharges the anode exhaust gas discharged from the anode of the fuel cell, and the control means includes a raw material amount supplied to the reformer and an output value of the fuel cell in the anode exhaust gas. The fuel cell system according to claim 1, wherein an amount of hydrogen is calculated, and an amount of air supplied to the auxiliary combustor is controlled based on the amount of hydrogen. An auxiliary combustor that takes in and combusts anode exhaust gas discharged from the anode of the fuel cell and preheats part of the raw material supplied to the reformer, and the control means supplies the raw material supplied to the reformer The amount of fuel to be supplied to the auxiliary combustor based on the preheating temperature or the amount of combustion air to be supplied to the reformer is calculated from the amount of fuel and the output value of the fuel cell. The fuel cell system according to claim 1, wherein at least one of the two is controlled.

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