FUEL CELL SYSTEM, MOTOR, AIR COMPRESSOR, PUMP, AND METHOD OF DESIGNING MOTOR

摘要

A fuel cell system (30) includes a fuel gas supply/discharge mechanism (50), an oxidative gas supply/discharge mechanism (60), and a coolant circulation mechanism (70) that cools a fuel cell. A motor (63) employed in an air compressor (62) of the fuel gas supply/discharge mechanism (50) includes a generally circular cylindrical rotor (110). The axial length L of the rotor is related to its diameter D such that the ratio L/D is approximately equal to a maximum value satisfying a relationship: Ta= Tm, where Ta denotes a permissible torque of the motor (63), and that Tm denotes a maximum torque for which a request is to be made to the motor (63).