Fuel cell system, fuel cell vehicle, and control method for the fuel cell system

PROBLEM TO BE SOLVED: To reduce the occurrence of overcharging of a secondary battery when the power consumption of a motor is rapidly reduced.SOLUTION: A fuel cell system incorporated in a vehicle includes: a fuel cell; a secondary battery; an SOC detection part for detecting a temperature of the secondary battery and a power storage amount thereof; an accelerator position detection part for detecting an accelerator step-down amount; and a control part for controlling generated power of the fuel cell. Further, the control part includes: a generation-required power calculation part for calculating generation-required power on the basis of the accelerator step-down amount, the temperature of the secondary battery, and the power storage amount; and an upper limit required power calculation part for calculating upper limit required power that can be generated by the fuel cell, on the basis of the accelerator step-down amount, the temperature of the secondary battery, and the power storage amount, where the upper limit required power includes permissible charging power correlated with an upper limit value of charging power. Further, when determining a condition that the power consumption of the motor is rapidly reduced, the control part calculates the upper limit required power with the permissible charging power set to zero, and causes the fuel cell to generate power corresponding to the upper limit required power in a case where the generation-required power exceeds the upper limit required power.SELECTED DRAWING: Figure 1