When the magnitude ω of a steering angular velocity w is equal to or greater than a determination angular velocity ωth, an electric motor is estimated to be in a predetermined power use state, and a restriction determination threshold Vonth is set to a first voltage value V1. When the magnitude ω of the steering angular velocity ω is less than the determination angular velocity ωth, the restriction determination threshold Vonth is set to a second voltage value V2 (>；V1). When a state in which a power supply voltage Vx is lower than the restriction determination threshold Vonth continues for a predetermined time t1, a power use restriction instruction is output to specific vehicle electrical loads. Thus, power restriction is properly imposed on the vehicle electrical loads, whereby a delay in control of the electric motor is prevented, and excessive imposition of power restriction is prevented.
