Fuel cell system with improved leak detection

Abstract

A fuel cell system comprises a fuel cell, a cooling system, a rotating speed acquisition part acquiring a rotating speed of the refrigerant pump, a power consumption acquisition part acquiring a power consumption of the refrigerant pump, and a controller configured to receive a rotating speed acquired by the rotating speed acquisition part and control the refrigerant pump. The controller has stored therein a predetermined correspondence between rotating speeds of the refrigerant pump and power consumption threshold values. The controller executes a refrigerant leak decision process for deciding presence or absence of a refrigerant leak while executing constant rotating speed control for the refrigerant pump, and in the refrigerant leak decision process, with reference to the correspondence by using a rotating speed value acquired by the rotating speed acquisition part, the controller determines a power consumption threshold value corresponding to the rotating speed value, and decides that a refrigerant leak has occurred if a power consumption value acquired by the power consumption acquisition part is equal to or lower than the power consumption threshold value corresponding to the rotating speed value.