Fuel cell system and control method therefor

Patent metadata

Field	Value
Publication number	US-10622652-B2
Application number	US-201615765909-A
Country	US
Kind code	B2
Filing date	Oct 31, 2016
Priority date	Oct 30, 2015
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

The present invention relates to a fuel cell system and a control method therefor. An aspect of the present invention provides a fuel cell system comprising: a fuel cell stack; a memory unit in which a plurality of current-voltage curves, which are determined according to operation conditions of the fuel cell stack, are stored; a measurement unit for detecting an operation condition of the fuel cell stack; and a control unit for calling a current-voltage curve which satisfies the operation condition of the fuel cell stack, detected by the measurement unit, and predicting the performance of the fuel cell stack according to the called current-voltage curve.

First claim

The invention claimed is:

1. A fuel cell system, comprising
a fuel cell stack comprising a membrane-electrode assembly (MEA), a gas diffusion layer (GDL), and a separating plate;
a memory unit storing a plurality of current-voltage curves determined according to operation conditions of the fuel cell stack;
a measurement unit for sensing an operation condition of the fuel cell stack; and
a control unit configured to:
call a first current-voltage curve among the plurality of current-voltage curves which satisfies the operation condition of the fuel cell stack, sensed by the measurement unit,
monitor performance of the fuel stack in real time,
predict the performance of the fuel cell stack according to the called first current-voltage curve, based on the sensed operation condition, and
control the current and voltage of the fuel cell stack according to the called first current-voltage curve,
wherein the plurality of current-voltage curves comprises different operation conditions from one another,
wherein a second current-voltage curve among the plurality of current-voltage curves comprises at a forward trajectory and a backward trajectory showing a hysteresis phenomena,
wherein a third current-voltage curve among the plurality of current-voltage curves comprises a backward performance lower than a forward performance due to an overflow of water accumulated inside a high density region of the fuel cell stack, and
wherein the operation conditions of the fuel cell stack include at least one of the following: an inflow concentration of a reaction gas, a pressure of a reaction gas, a humidity of a reaction gas, or a cell temperature.

2. The fuel cell system according to claim 1 ,
wherein at least one of the plurality of current-voltage curves has a forward trajectory and a backward trajectory showing a hysteresis phenomena and both trajectories having one or more intersection points.

3. The fuel cell system according to claim 1 ,
wherein said measurement unit comprises at least one of a temperature sensor, a pressure sensor, a humidity sensor or a flow rate sensor.

4. The fuel cell system according to claim 3 ,
wherein the control unit is provided to collect operation conditions of the fuel cell stack in real time through the measurement unit.

5. The fuel cell system according to claim 3 ,
wherein said control unit is further provided to control at least one of temperature, pressure, humidity, or flow rate according to the called first current-voltage curve.

6. The fuel cell system according to claim 1 ,
wherein said control unit is provided to receive current and voltage data of the fuel cell stack via the measurement unit.

7. The fuel cell system according to claim 6 ,
wherein said control unit matches the measured current and voltage data with the collected operation conditions of the fuel cell and stores them together.

8. The fuel cell system according to claim 1 ,
wherein the performance of the fuel cell stack is a current density generated under a specific voltage condition.

9. The fuel cell system according to claim 1 ,
wherein the control unit is provided to generate an operation control rule of the fuel cell stack for classifying the plurality of current-voltage curves according to the operation conditions of the fuel cell stack, and to evaluate the generated operation control rule.

10. The fuel cell system according to claim 9 ,
wherein in a process of predicting the performance of the fuel cell stack based on any one of the plurality of current-voltage curves, the control unit is provided to predict the performance of the fuel cell stack based on another one of the current-voltage curves according to the operation control rule, when the operation condition of the fuel cell stack is changed.

11. A method for controlling a fuel cell system, comprising steps of:
storing a plurality of current-voltage curves determined according to operation conditions of a fuel cell stack, wherein the fuel cell stack includes a membrane-electrode assembly (MEA), a gas diffusion layer (GDL), and a separating plate;
sensing an operation condition of the fuel cell stack;
calling a first current-voltage curve among the plurality of current-voltage curves which satisfies the sensed operation condition of the fuel cell stack;
monitoring performance of the fuel cell stack in real time;
predicting the performance of the fuel cell stack according to the called first current-voltage curve, based on the sensed operation condition; and
controlling the current and voltage of the fuel cell stack according to the called first current-voltage curve,
wherein the plurality of current-voltage curves comprises different operational conditions,
wherein a second current-voltage curve among the plurality of current-voltage curves comprises at a forward trajectory and a backward trajectory showing a hysteresis phenomena,
wherein a third current-voltage curve among the plurality of current-voltage curves comprises a backward performance lower than a forward performance due to an overflow of water accumulated inside a high density region of the fuel cell stack, and
wherein the operation conditions of the fuel cell stack includes at least two of the following: an inflow concentration of a reaction gas, a pressure of a reaction gas, a humidity of a reaction gas, or a cell temperature.

12. The method according to claim 11 , the predicting the performance of the fuel cell stack includes predicting the performance of the fuel cell stack based on another one of the current-voltage curves, when the operation condition of the fuel cell stack is changed.

13. The method according to claim 11 , wherein at least one of the plurality of current-voltage curves has a forward trajectory and a backward trajectory showing a hysteresis phenomena and both trajectories having one or more intersection points.

14. The method according to claim 11 , wherein said measurement unit comprises at least one of a temperature sensor, a pressure sensor, a humidity sensor or a flow rate sensor.

Assignees

• Lg Chemical Ltd

Inventors

• Kong Chang Sun
• Yang Jae Choon

Classifications

• H01M8/045

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

• H01M8/04746 Primary

  Pressure; Flow · CPC title

• H01M8/04335

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

• H01M8/04589

  of fuel cell stacks · CPC title

• H01M8/04388

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