In-wheel motor system is recognized as the ideal drive system for electric vehicles. To reduce mechanical shock and electromagnetic impulsion brought by rigid connection between hubs and motor, our group proposed a novel permanent bistable electromagnetic clutch which flexibly connecting the motor and hubs. In this paper, several power supply schemes for the clutch are proposed and compared, then, pulsed power supply as a better scheme is further studied and optimal designed. Subsequently, the capacitance, charging voltage, coil turns and coil diameter are determined. Finally, experiments verified the power supply system we proposed.