Fuel cell system and method for controlling fuel cell system

Patent metadata

Field	Value
Publication number	US-2019088962-A1
Application number	US-201616086867-A
Country	US
Kind code	A1
Filing date	Dec 8, 2016
Priority date	Mar 22, 2016
Publication date	Mar 21, 2019
Grant date	—

Abstract

A fuel cell system includes a fuel cell configured to be supplied with an anode gas and a cathode gas and generate electric power, a compressor configured to supply the cathode gas to the fuel cell, a turbine configured to be supplied with a cathode discharged gas discharged from the fuel cell and generate power, an electric motor connected to the compressor and the turbine and configured to perform power running and regeneration, a combustor disposed between the fuel cell and the turbine and configured to mix and combust the cathode gas and the anode gas, a cooler configured to cool the cathode gas that is supplied from the compressor to the fuel cell, a bypass passage configured to supply the cathode gas from an upstream side of the cooler to the combustor by bypassing the cooler and the fuel cell, and a bypass valve disposed in the bypass passage.

First claim

1 .- 8 . (canceled)

9 . A fuel cell system comprising:
a fuel cell configured to be supplied with an anode gas and a cathode gas and generate electric power; a compressor configured to supply the cathode gas to the fuel cell; a turbine configured to be supplied with a cathode discharged gas discharged from the fuel cell and generate power; an electric motor connected to the compressor and the turbine and configured to perform power running and regeneration; a combustor disposed between the fuel cell and the turbine and configured to mix and combust the cathode gas and the anode gas; a cooler configured to cool the cathode gas that is supplied from the compressor to the fuel cell; a bypass passage configured to supply the cathode gas from an upstream side of the cooler to the combustor by bypassing the cooler and the fuel cell; a bypass valve disposed in the bypass passage; and a control unit configured to control the bypass valve based on a system required output, wherein the control unit is configured to, when the system required output is equal to or greater than a predetermined output, increase an opening degree of the bypass valve according to an increase in the system required output.

10 . The fuel cell system according to claim 9 , wherein the control unit is configured to control the opening degree of the bypass valve based on a target value of a pressure ratio of the compressor to an atmospheric pressure.

11 . The fuel cell system according to claim 9 , wherein the control unit is configured to control a flow rate of the compressor based on a system required output that is determined based on a load connected to the fuel cell, and an outputtable electric power that is possible to be output by the fuel cell.

12 . The fuel cell system according to claim 9 , wherein the cooler is configured to perform heat exchange with the fuel cell.

13 . A fuel cell system control method executed in a fuel cell system including: a fuel cell configured to be supplied with an anode gas and a cathode gas and generate electric power; a compressor configured to supply the cathode gas to the fuel cell; a turbine configured to be supplied with a cathode discharged gas discharged from the fuel cell and generate power; an electric motor connected to the compressor and the turbine and configured to perform power running and regeneration; a combustor disposed between the fuel cell and the turbine and configured to mix and combust the cathode gas and the anode gas; a cooler configured to cool the cathode gas that is supplied from the compressor to the fuel cell; a bypass passage configured to supply the cathode gas from an upstream side of the cooler to the combustor by bypassing the cooler and the fuel cell; and a bypass valve disposed in the bypass passage,
the method comprising: controlling the bypass valve based on a system required output; and when the system required output is equal to or greater than a predetermined output, increasing an opening degree of the bypass valve according to an increase in the system required output.

14 . A fuel cell system comprising:
a fuel cell configured to be supplied with an anode gas and a cathode gas and generate electric power; a compressor configured to supply the cathode gas to the fuel cell; a turbine configured to be supplied with a cathode discharged gas discharged from the fuel cell and generate power; an electric motor connected to the compressor and the turbine and configured to perform power running and regeneration; a combustor disposed between the fuel cell and the turbine and configured to mix and combust the cathode gas and the anode gas; a cooler configured to cool the cathode gas that is supplied from the compressor to the fuel cell; a bypass passage configured to supply the cathode gas from an upstream side of the cooler to the combustor by bypassing the cooler and the fuel cell; a bypass valve disposed in the bypass passage; and a control unit configured to control the bypass valve, wherein the control unit is configured to control an opening degree of the bypass valve based on a temperature of air discharged from the compressor.

15 . A fuel cell system comprising:
a fuel cell configured to be supplied with an anode gas and a cathode gas and generate electric power; a compressor configured to supply the cathode gas to the fuel cell; a turbine configured to be supplied with a cathode discharged gas discharged from the fuel cell and generate power; an electric motor connected to the compressor and the turbine and configured to perform power running and regeneration; a combustor disposed between the fuel cell and the turbine and configured to mix and combust the cathode gas and the anode gas; a cooler configured to cool the cathode gas that is supplied from the compressor to the fuel cell; a bypass passage configured to supply the cathode gas from an upstream side of the cooler to the combustor by bypassing the cooler and the fuel cell; a bypass valve disposed in the bypass passage; and a control unit configured to control the bypass valve, wherein the control unit is configured to, after an inlet temperature of the turbine has reached an allowable upper limit temperature, increase a flow rate of the compressor to more than a flow rate required by the fuel cell.

Assignees

• Nissan Motor

Inventors

• Chikugo Hayato
• Tomita Yousuke

Classifications

• H01M2250/10

  Fuel cells in stationary systems, e.g. emergency power source in plant · CPC title

• F02C9/18

  by bleeding, bypassing or acting on variable working fluid interconnections between turbines or compressors or their stages {(F02C3/113 takes precedence)} · CPC title

• F05D2210/12

  gaseous, i.e. compressible · CPC title

• H01M8/04111 Primary

  using a compressor turbine assembly · CPC title

• F02C6/10

  supplying working fluid to a user, e.g. a chemical process, which returns working fluid to a turbine of the plant · CPC title