Fuel cell system and control method thereof

Abstract

A fuel cell system comprises a fuel cell stack, a circulation flow path of a cooling medium, a pump provided in the circulation flow path, a supply-side temperature sensor provided to detect a supplied cooling medium temperature, a discharge-side temperature sensor provided to detect a discharged cooling medium temperature, and a cold-start controller configured to control a circulation volume of the cooling medium by the pump at a cold start of the fuel cell stack. The cold-start controller estimates a fuel cell internal temperature and selectively sets the circulation volume of the cooling medium between a reduced volume and a normal volume, based on a magnitude relationship between the internal temperature and the discharged cooling medium temperature. When the supplied cooling medium temperature becomes equal to the discharge cooling medium temperature after setting the circulation volume, the cold-start controller sets the circulation volume of the cooling medium to an increased volume (maximum circulation volume).

Description

technical field [0001] The present invention relates to a fuel cell system including a fuel cell stack and a control method for the fuel cell system. Background technique [0002] Conventionally, in a fuel cell system, when starting a fuel cell stack, when the internal temperature of the fuel cell is below 0° C., a technique has been proposed in which the pump of the cooling water is stopped to stop the circulation of the cooling water (e.g. , refer to Patent Document 1). According to this technology, it is possible to increase the calorific value after starting below the freezing point, and to increase the temperature increase rate of the fuel cell stack to shorten the start-up time. [0003] Patent Document 1: Japanese Patent Laid-Open No. 2010-186599 [0004] However, according to the aforementioned prior art, if the circulation of the cooling water continues to be stopped, there will be a portion in which the temperature rises slowly in the stacking direction of the fu...

AI Technical Summary

Problems solved by technology

[0004] However, according to the above-mentioned prior art, if the circulation of cooling water continues to be stopped, there will be a portion where the temperature rises slowly in the stacking direction of the fuel cell stack, and there is a problem that the temperature of the entire fuel cell stack cannot be uniformly raised.

Images