Electrical power steering system for vehicle, has control unit controlling power conversion device for continuous supply of alternating current power to brushless motor when one of power switching devices is short circuit

摘要

The system (1) has a brushless motor (3) for generating a torque to support a steering wheel. A power conversion device (50) includes power switching devices (50a-50f) switched in a bridge form. The device converts direct current power into an alternating current power with multiple phases that correspond to the motor in order to supply the alternating power to the motor. A control unit (55) controls the device for continuous supply of the alternating power to the motor when one of the power devices is short circuit and the power device has a short-circuit error separated from the motor.