Fuel cell system

Patent metadata

Field	Value
Publication number	US-11705563-B2
Application number	US-202117492849-A
Country	US
Kind code	B2
Filing date	Oct 4, 2021
Priority date	Oct 7, 2020
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A fuel cell system includes a control unit that detects an abnormality of a flow dividing valve provided in a bypass channel for an oxidation gas by using a detected opening degree detected by a valve opening degree detection sensor that detects the opening degree of the flow dividing valve. When the detected abnormality is an opening abnormality that is failure to open and the flow dividing valve can close, the control unit sends a closing command for making the opening degree smaller than a current opening degree to a valve driving motor. Either when the detected abnormality is a closing abnormality that is failure to close and the flow dividing valve can open or when the detected abnormality is an opening-closing abnormality that is failure both to close and to open, the control unit sends a maintaining command for maintaining the opening degree to the valve driving motor.

First claim

What is claimed is:

1. A fuel cell system comprising:
a fuel cell;
an oxidation gas supply channel through which an oxidation gas is supplied to the fuel cell;
an oxidation off-gas discharge channel through which an oxidation off-gas is discharged from the fuel cell;
a bypass channel that connects the oxidation gas supply channel and the oxidation off-gas discharge channel to each other;
a flow dividing valve that is provided in the bypass channel to divide a flow of the oxidation gas flowing through the oxidation gas supply channel into a flow toward the fuel cell and a flow toward the bypass channel;
a valve driving motor that adjusts an opening degree of the flow dividing valve;
a valve opening degree detection sensor that detects the opening degree of the flow dividing valve; and
a control unit configured to control operation of the flow dividing valve by controlling the valve driving motor, and to detect a detected abnormality of the flow dividing valve using a detected opening degree that is the opening degree of the flow dividing valve detected by the valve opening degree detection sensor, wherein the control unit is configured such that:
when the detected abnormality is an opening abnormality that is failure to open and the flow dividing valve is able to close, the control unit sends a closing command for making the opening degree smaller than a current opening degree to the valve driving motor; and
either when the detected abnormality is a closing abnormality that is failure to close and the flow dividing valve is able to open or when the detected abnormality is an opening-closing abnormality that is failure both to close and to open, the control unit sends a maintaining command for maintaining the opening degree to the valve driving motor.

2. The fuel cell system according to claim 1 , wherein the control unit is configured to control the valve driving motor by sending a sent opening degree signal to the valve driving motor, and to detect the detected abnormality when an opening degree difference between an opening degree indicated by the sent opening degree signal and the detected opening degree is not smaller than a predetermined opening degree difference.

3. The fuel cell system according to claim 2 , wherein the control unit is configured to, upon detecting the detected abnormality, send a predetermined opening degree signal to the valve driving motor to determine if the detected abnormality is the opening abnormality or the closing abnormality.

4. The fuel cell system according to claim 1 , wherein the control unit is configured such that, when the detected abnormality is the opening abnormality and the flow dividing valve is able to close, the control unit sends, as the closing command, a command for adjusting the opening degree to a minimum opening degree to the valve driving motor.

5. A fuel cell system comprising:
a fuel cell;
an oxidation gas supply channel through which an oxidation gas is supplied to the fuel cell;
an oxidation off-gas discharge channel through which an oxidation off-gas is discharged from the fuel cell;
a flow control valve that is at least one of a first valve that is disposed in the oxidation gas supply channel and adjusts a flow of the oxidation gas and a second valve that is disposed in the oxidation off-gas discharge channel and adjusts a flow of the oxidation off-gas;
a valve driving motor that adjusts an opening degree of the flow control valve;
a valve opening degree detection sensor that detects the opening degree of the flow control valve; and
a control unit configured to control operation of the flow control valve by controlling the valve driving motor, and to detect a detected abnormality of the flow control valve using a detected opening degree that is the opening degree of the flow control valve detected by the valve opening degree detection sensor, wherein the control unit is configured such that:
when the detected abnormality is a closing abnormality that is failure to close and the flow control valve is able to open, the control unit sends an opening command for making the opening degree larger than a current opening degree to the valve driving motor; and
either when the detected abnormality is an opening abnormality that is failure to open and the flow control valve is able to close or when the detected abnormality is an opening-closing abnormality that is failure both to open and to close, the control unit sends a maintaining command for maintaining the opening degree to the valve driving motor.

6. The fuel cell system according to claim 5 , wherein the control unit is configured to control the valve driving motor by sending a sent opening degree signal to the valve driving motor, and to detect the detected abnormality when an opening degree difference between an opening degree indicated by the sent opening degree signal and the detected opening degree is not smaller than a predetermined opening degree difference.

7. The fuel cell system according to claim 6 , wherein the control unit is configured to, upon detecting the detected abnormality, send a predetermined opening degree signal to the valve driving motor to determine if the detected abnormality is the opening abnormality or the closing abnormality.

8. The fuel cell system according to claim 5 , wherein the control unit is configured such that, when the detected abnormality is the closing abnormality and the flow control valve is able to open, the control unit sends, as the opening command, a command for adjusting the opening degree to a maximum opening degree to the valve driving motor.

Assignees

• Toyota Motor Co Ltd
• Aisan Ind

Inventors

• Fujimura Yoshikatsu
• Otsuka Shinobu
• Oikawa Jiro

Classifications

• H01M8/04664 Primary

  Failure or abnormal function · CPC title

• H01M8/04089 Primary

  of gaseous reactants · CPC title

• H01M8/04746

  Pressure; Flow · CPC title

• H01M8/04694

  characterised by variables to be controlled · CPC title

• Y02E60/50

  Fuel cells · CPC title