Method for operating fuel cell system

Patent metadata

Field	Value
Publication number	US-2016336608-A1
Application number	US-201615221602-A
Country	US
Kind code	A1
Filing date	Jul 28, 2016
Priority date	Jan 26, 2011
Publication date	Nov 17, 2016
Grant date	—

Abstract

A method for operating a fuel cell system includes detecting a pressure in a fuel supply path located downstream of a pressure reducing valve using a pressure sensor. Whether or not the pressure detected by the pressure sensor exceeds a predetermined threshold pressure is determined. The pressure in the fuel supply path located downstream of the pressure reducing is reduced when the pressure detected by the pressure sensor exceeds the predetermined threshold pressure.

First claim

What is claimed is:

1 . A method for operating a fuel cell system that includes a fuel cell, a fuel-gas supplier, a fuel supply path connecting the fuel cell to the fuel-gas supplier, a shut-off valve to switch between a supply mode and a shut-off mode for fuel gas supplied toward the fuel supply path from the fuel-gas supplier, a pressure reducing valve provided in the fuel supply path between the shut-off valve and the fuel cell to reduce a downstream pressure relative to an upstream pressure, and a controller, the method comprising:
detecting a pressure in the fuel supply path located downstream of the pressure reducing valve using a pressure sensor; determining whether or not the pressure detected by the pressure sensor exceeds a predetermined threshold pressure; and reducing the pressure in the fuel supply path located downstream of the pressure reducing valve when the pressure detected by the pressure sensor exceeds the predetermined threshold pressure.

2 . The method according to claim 1 , wherein
whether or not the pressure detected by the pressure sensor exceeds the predetermined threshold pressure is determined when the fuel cell is activated.

3 . The method according to claim 2 , wherein
if the pressure detected by the pressure sensor exceeds the predetermined threshold pressure when the fuel cell is activated, the controller controls a depressurizing device to reduce the pressure in the fuel supply path located downstream of the pressure reducing valve to the predetermined threshold pressure or to a pressure lower than the predetermined threshold pressure, and subsequently opens the shut-off valve and actuates an auxiliary device so as to activate the fuel cell.

4 . The method according to claim 3 , wherein
the depressurizing device includes a low-pressure open valve provided in the fuel supply path located downstream of the pressure reducing valve, the low-pressure open valve being to switch the fuel supply path between a state in which the fuel supply path is in communication with a low-pressure area with a pressure lower than the predetermined threshold pressure and a state in which the fuel supply path is shut off from the low-pressure area, and the controller opens the low-pressure open valve so as to reduce the pressure in the fuel supply path located downstream of the pressure reducing valve, and includes a pressure responsive valve provided in the fuel supply path located downstream of the pressure reducing valve, the pressure responsive valve being to switch from a closed state to an open state when the pressure in the fuel supply path located downstream of the pressure reducing valve exceeds an upper limit pressure set to be higher than the predetermined threshold pressure so as to allow the fuel supply path to communicate with the low-pressure area.

5 . The method according to claim 3 , wherein
the predetermined threshold pressure is set based on a maximum normal pressure value of the auxiliary device.

6 . The method according to claim 1 , wherein
the fuel cell is not activated until the pressure in the fuel supply path located downstream of the pressure reducing valve decreases to the predetermined threshold pressure.

7 . The method according to claim 3 , further comprising:
opening the shut-off valve when the pressure in the fuel supply path located downstream of the pressure reducing valve decreases to the predetermined threshold pressure or lower; and actuating the auxiliary device after opening the shut-off valve such that supply of the fuel gas to the fuel cell commences.

8 . The method according to claim 1 , wherein
whether or not the pressure detected by the pressure sensor exceeds a predetermined threshold pressure is determining when an ignition switch is turned on.

Assignees

• Honda Motor Co Ltd

Inventors

• Kato Koichi
• Takaku Koichi

Classifications

• H01M2250/20

  Fuel cells in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M8/04201

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

• H01M8/04753

  of fuel cell reactants · CPC title

• H01M8/04432 Primary

  Pressure differences, e.g. between anode and cathode · CPC title

• H01M8/04388 Primary

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