Fuel cell system and method of controlling the same

Patent metadata

Field	Value
Publication number	US-10461348-B2
Application number	US-201615143789-A
Country	US
Kind code	B2
Filing date	May 2, 2016
Priority date	Dec 11, 2015
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A fuel cell system and a method of controlling the same are provided. The fuel cell system includes a supplying pipe that supplies hydrogen and air to a stack and a gas concentration sensor that senses hydrogen and air impurities supplied to the supplying pipe. A supplying valve is disposed in the supplying pipe to adjust the hydrogen and air supply and a discharging pipe discharges the hydrogen and the air from the stack. A discharging valve is disposed in the discharging pipe to adjust the discharging of the hydrogen and the air. A controller operates with the gas concentration sensor to detect introduction of the impurities. Exhaust valves are disposed at the front and rear end of the stack to remove a polluted fuel when the impurities are introduced. When performance deteriorates due to the impurities, a cause of deterioration is determined, and stack performance is recovered.

First claim

What is claimed is:

1. A fuel cell system, comprising:
a supplying pipe configured to supply hydrogen and air to a stack;
a gas concentration sensor configured to sense impurities of the hydrogen and the air supplied to the supplying pipe;
a supplying valve disposed in the supplying pipe to adjust the supplying of the hydrogen and the air;
a discharging pipe configured to discharge the hydrogen and the air from the stack;
a discharging valve disposed in the discharging pipe to adjust the discharging of the hydrogen and the air;
a controller configured to be operated together with the gas concentration sensor to detect introduction of the impurities; and
exhaust valves disposed at a front end and a rear end of the stack to remove a polluted fuel in response to detecting the introduction of the impurities,
wherein the controller is further configured to:
determine whether a stack voltage is dropped due to the impurities of the hydrogen;
control the supplying valve and the exhaust valves to exhaust hydrogen and air in the stack and to supply hydrogen and air into the stack when it is determined that the stack voltage is dropped due to the impurities of the hydrogen; and
perform a logic of repeating start-on/off of the fuel cell system for predetermined times.

2. The fuel cell system according to claim 1 , further comprising:
a stack inlet blocking valve disposed between the supplying pipe and the stack to block introduction of the hydrogen or the air into the stack.

3. The fuel cell system according to claim 1 , wherein:
the supplying pipe includes: a hydrogen supplying pipe configured to supply the hydrogen and an air supplying pipe configured to supply the air,
the gas concentration sensor includes a hydrogen gas concentration sensor configured to sense the impurities of the hydrogen and an air gas concentration sensor configured to sense the impurities of the air,
the supplying valve includes a hydrogen supplying valve configured to adjust the supplying of the hydrogen and an air supplying valve configured to adjust the supplying of the air,
the discharging pipe includes a hydrogen discharging pipe configured to discharge the hydrogen and an air discharging pipe configured to discharge the air, and
the discharging valve includes a hydrogen discharging valve configured to adjust the discharging of the hydrogen and an air discharging valve configured to adjust the discharging of the air.

4. The fuel cell system according to claim 1 , wherein the controller includes:
a controlling part configured to store a driving condition including temperature, humidification, and pressure while a vehicle is being driven to determine whether the driving condition is normal and a level of normality; and
a diagnosing part configured to be operated together with the controlling part and determine the driving condition and a diagnosed resistance value to determine whether the impurities are introduced and a level of the introduction of the impurities using the controlling part.

5. The fuel cell system according to claim 4 , wherein the controlling part is configured to recover performance of the stack after the fuel is removed.

6. A method of controlling a fuel cell system, comprising:
measuring, by a controller, a stack voltage during driving of a fuel cell vehicle after hydrogen is charged in the fuel cell vehicle using a sensor;
determining, by the controller, whether the stack voltage is less than a reference voltage;
confirming a driving condition when the stack voltage is less than the reference voltage;
determining whether the driving condition is normal;
exhausting, by the controller, hydrogen in a stack and supplying, by the controller, hydrogen into the stack when the driving condition is normal; and
performing, by the controller, a logic of repeating start-on/off of the fuel cell system.

7. The method of controlling a fuel cell system according to claim 6 , wherein the driving condition includes temperature, pressure, coolant, and humidification states.

8. The method of controlling a fuel cell system according to claim 6 , wherein, in the step of determining whether the stack voltage is less than the reference voltage, when the stack voltage is greater than or equal to the reference voltage, it is determined, by the controller, that a purity of the hydrogen is normal.

9. The method of controlling a fuel cell system according to claim 6 , further comprising determining that a performance of the fuel cell system is deteriorated due to the driving condition when the driving condition is not normal.

10. The method of controlling a fuel cell system according to claim 6 , further comprising:
determining, by the controller, whether the fuel cell vehicle requires additional driving for a predetermined period of time; and
controlling to open an air blocking valve based on start-off of the fuel cell system when the fuel cell vehicle does not require additional driving.

11. The method of controlling a fuel cell system according to claim 6 , further comprising:
determining, by the controller, whether a performance of the stack is recovered; and determining, by the controller, that the performance reaches a normal state to end the logic of repeating start-on/off of the fuel cell system when the performance of the stack is recovered.

Assignees

• Hyundai Motor Co Ltd

Inventors

• Im Se Joon
• Paek Jun Yeol

Classifications

• H01M8/04492

  Humidity; Ambient humidity; Water content · CPC title

• H01M8/04559

  of fuel cell stacks · CPC title

• H01M8/0438

  Pressure; Ambient pressure; Flow · CPC title

• H01M8/04798 Primary

  of fuel cell reactants · CPC title

• H01M8/04447

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