Electric power steering apparatus

摘要

A controller for controlling the assist steering torque of an electric motor in an electric power steering apparatus has a relay failure detection unit for detecting ON failure which arises in a relay circuit provided between an electric motor driving circuit and a power supply; and a relay failure correction unit for decreasing the assist steering torque, at least the maximum value of the assist steering torque, of the electric motor based on a failure detection signal from the relay failure detection unit. Thereby, manual steering by a steering wheel with a heavier steering torque than the torque at the time of a normal mode becomes possible as deal at the time that ON failure arises in a relay circuit.