Fuel cell system and method of controlling same

Patent metadata

Field	Value
Publication number	US-11862824-B2
Application number	US-202117409941-A
Country	US
Kind code	B2
Filing date	Aug 24, 2021
Priority date	Dec 15, 2020
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

Proposed are a fuel cell system and a method of controlling the fuel cell system. The fuel cell system includes: a hydrogen supply unit connected to a hydrogen inlet side of a fuel cell stack, with a supply valve and a sensor being provided in the hydrogen supply unit; a hydrogen discharge unit connected to a hydrogen outlet side of the fuel cell stack, with a water trap and a purge valve being provided in the hydrogen discharge unit; and a controller configured to calculate an amount of hydrogen discharged through the purge valve from an amount of hydrogen supplied to the fuel cell stack and an amount of hydrogen consumed therein, and to perform compensation control of the supply valve when the amount of the discharged hydrogen is at or above a reference value.

First claim

What is claimed is:

1. A fuel cell system comprising:
a hydrogen supply unit connected to a hydrogen inlet side of a fuel cell stack, with a supply valve and a sensor being provided in the hydrogen supply unit;
a hydrogen discharge unit connected to a hydrogen outlet side of the fuel cell stack, with a water trap and a purge valve being provided in the hydrogen discharge unit; and
a controller configured to calculate an amount of hydrogen discharged through the purge valve from an amount of hydrogen supplied to the fuel cell stack and an amount of hydrogen consumed therein, and to perform compensation control of the supply valve when the amount of the discharged hydrogen is at or above a reference value,
wherein the controller calculates the amount of the discharged hydrogen from the amount of the supplied hydrogen, the amount of the consumed hydrogen, and an amount of hydrogen pressurized in the fuel cell stack,
wherein the controller calculates the amount of the pressurized hydrogen from internal pressure of a hydrogen electrode of the fuel cell stack, and
wherein when the amount of the discharged hydrogen is at or above the reference value, the controller determines a compensation value based on a hydrogen purge map from the amount of the discharged hydrogen, and controls the supply valve with a value obtained by adding the compensation value to a control value with which the supply valve is controlled, thereby preventing an undershoot or an overshoot in the amount of the supplied hydrogen.

2. The fuel cell system of claim 1 , wherein the sensor is a pressure sensor and is provided between the supply valve and an ejector.

3. The fuel cell system of claim 1 , wherein the purge valve is provided underneath the water trap, and when the purge valve is opened, condensate water within the water trap is first discharged, and then hydrogen is discharged.

4. The fuel cell system of claim 1 , wherein the controller calculates the amount of the supplied hydrogen from pressure of the supplied hydrogen, which is measured through the sensor, or from a flow rate of the hydrogen.

5. The fuel cell system of claim 1 , wherein the controller calculates the amount of the consumed hydrogen from electric current that is output from the fuel cell stack.

6. The fuel cell system of claim 1 , wherein the controller calculates the amount of the discharged hydrogen by subtracting the amount of the consumed hydrogen from the amount of the supplied hydrogen.

7. The fuel cell system of claim 1 , wherein the controller calculates the amount of the discharged hydrogen by subtracting the amount of the consumed hydrogen and the amount of the hydrogen pressurized in the fuel cell stack from the amount of the supplied hydrogen.

8. A method of controlling the fuel cell system according to claim 1 , the method comprising:
calculating an amount of hydrogen supplied to the fuel cell stack and an amount of hydrogen consumed therein;
calculating an amount of discharged hydrogen from the amount of the hydrogen supplied to the fuel cell stack and the amount of the hydrogen consumed therein;
determining whether or not the amount of the discharged hydrogen is at or above a reference value; and
performing compensation control for the amount of the hydrogen supplied through the supply valve when the amount of the discharged hydrogen is at or above the reference value.

9. The method of claim 8 , wherein, in the calculating of the amount of the discharged hydrogen, the amount of the discharged hydrogen is calculated from the amount of the supplied hydrogen, the amount of the consumed hydrogen, and an amount of hydrogen pressurized in the fuel cell stack.

10. The method of claim 9 , wherein, in the calculating of the amount of the discharged hydrogen, the amount of the discharged hydrogen is calculated by subtracting the amount of the consumed hydrogen and the amount of the hydrogen pressurized in the fuel cell stack from the amount of the supplied hydrogen.

11. The method of claim 8 , wherein, in the performing of the compensation control for the amount of the supplied hydrogen, when the amount of the discharged hydrogen is at or above the reference value, a compensation value is calculated from the amount of the discharged hydrogen, and the supply valve is controlled with a value obtained by adding the compensation value to a control value with which the supply valve is controlled, thereby preventing an undershoot or an overshoot in the amount of the supplied hydrogen.

Assignees

• Hyundai Motor Co Ltd
• Kia Corp

Inventors

• Jung Jae Won
• Kim Hak Yoon
• Park Jun Young
• Jeong Seong Cheol

Classifications

• H01M8/04179 Primary

  by purging or increasing flow or pressure of reactants · CPC title

• H01M8/0491

  of fuel cell stacks · CPC title

• H01M8/04753 Primary

  of fuel cell reactants · CPC title

• H01M8/04089 Primary

  of gaseous reactants · CPC title

• H01M8/0438

  Pressure; Ambient pressure; Flow · CPC title