Fuel cell system control method and fuel cell system

Patent metadata

Field	Value
Publication number	US-2020168933-A1
Application number	US-201716630660-A
Country	US
Kind code	A1
Filing date	Jul 31, 2017
Priority date	Jul 31, 2017
Publication date	May 28, 2020
Grant date	—

Abstract

According to a control method of controlling a fuel cell system, the fuel cell system including a solid oxide fuel cell that is supplied with an anode gas and a cathode gas to generate electric power, a fuel processor that at least reforms fuel to generate the anode gas and supplies the generated anode gas to the fuel cell, and a combustor that combusts the supplied fuel to perform warming of the fuel processor, the method is conducted when warming is performed at least at starting-up of the system. The method comprising: a cathode gas supply step of supplying the cathode gas to the fuel processor; a determining step of determining whether a temperature of gas passing through the fuel processor is higher than a temperature at which reforming is possible; a cathode gas decreasing step of decreasing a supplied amount of the cathode gas to the fuel processor when it is determined that the temperature of the gas is higher than the temperature at which reforming is possible; and a fuel supply step of supplying the fuel to the fuel processor.

First claim

1 . A fuel cell system control method of controlling a fuel cell system when warming is performed at least at starting-up of the system, the fuel cell system including a solid oxide fuel cell that is supplied with an anode gas and a cathode gas to generate electric power, a fuel processor that at least reforms fuel to generate the anode gas and supplies the generated anode gas to the fuel cell, and a combustor that combusts the supplied fuel to perform warming of the fuel processor, the method comprising:
a cathode gas supply step of supplying the cathode gas to the fuel processor; a determining step of determining whether a temperature of gas passing through the fuel processor is higher than a temperature at which reforming is possible; a cathode gas decreasing step of decreasing a supplied amount of the cathode gas to the fuel processor when it is determined that the temperature of the gas is higher than the temperature at which reforming is possible; and a fuel supply step of supplying the fuel to the fuel processor.

2 . The fuel cell system control method according to claim 1 , wherein the cathode gas decreasing step includes stopping supply of the cathode gas to the fuel processor.

3 . The fuel cell system control method according to claim 1 , further comprising:
a cathode gas increasing step of increasing the supplied amount of the cathode gas to the fuel processor when a predetermined waiting time has passed after supply of the fuel is started by the fuel supply step.

4 . The fuel cell system control method according to claim 3 , wherein
the fuel is liquid fuel, the fuel processor includes an evaporator that evaporates the liquid fuel to generate fuel gas and a reformer that reforms the fuel gas to generate the anode gas, and the predetermined waiting time is a time from starting to supply the liquid fuel by the fuel supply step to a timing at which a flow rate of the fuel gas to be supplied to the reformer from the evaporator is higher than a threshold.

5 . The fuel cell system control method according to claim 4 , further comprising:
a waiting time setting step of setting the waiting time shorter as a temperature of the liquid fuel is higher.

6 . The fuel cell system control method according to claim 4 , wherein
the determining step includes determining whether the temperature of the gas is higher than the temperature at which reforming is possible and a temperature of the evaporator is higher than a vaporizable temperature of the fuel, and the cathode gas decreasing step includes decreasing the supplied amount of the cathode gas to the fuel processor when it is determined that the temperature of the gas is higher than the temperature at which reforming is possible and the temperature of the evaporator temperature is higher than the vaporizable temperature.

7 . The fuel cell system control method according to claim 1 , further comprising:
a cathode gas stopping step of stopping supply of the cathode gas to the fuel processor when the temperature of the gas is higher than a warming completion temperature higher than the temperature at which reforming is possible.

8 . A fuel cell system comprising:
a solid oxide fuel cell that is supplied with an anode gas and a cathode gas to generate electric power; a fuel processor that at least reforms fuel to generate the anode gas and supplies the generated anode gas to the fuel cell; a combustor that combusts the supplied fuel to perform warming of the fuel processor; a fuel supply unit configured to send the fuel to the fuel processor and the combustor; a cathode gas supply unit configured to supply the cathode gas to the fuel processor; and a controller that controls the fuel supply unit and the cathode gas supply unit when the warming is performed at least at starting-up of the system, wherein the controller is configured to: cause the cathode gas supply unit to supply the cathode gas to the fuel processor; determine whether a temperature of gas passing through the fuel processor is higher than a temperature at which reforming is possible; cause the cathode gas supply unit to decrease a supplied amount of the cathode gas to the fuel processor when it is determined that the temperature of the gas is higher than the temperature at which reforming is possible; and cause the fuel supply unit to supply the fuel to the fuel processor.

Assignees

• Nissan Motor

Inventors

• Yaguchi Tatsuya
• Chikugo Hayato

Classifications

• H01M8/04302

  applied during start-up · CPC title

• H01M8/04225

  during start-up · CPC title

• H01M8/04328

  of anode reactants at the inlet or inside the fuel cell · CPC title

• H01M8/04201

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title

• H01M8/0606

  with means for production of gaseous reactants · CPC title