Electric power steering apparatus

摘要

An electric power steering apparatus transmits a driving force of an electric motor to a steering mechanism for steering assist. The apparatus includes a torque sensor which detects a steering wheel torque; a basic assist characteristic determining section which determines a basic assist characteristic defining a basic characteristic of a motor driving target value for the steering torque; a motor driving target value determining section which determines the motor driving target value for the steering torque in accordance with a modified assist characteristic prepared by shifting the basic assist characteristic along a steering torque coordinate axis; a shift amount determining section which determines the amount of the shift from the basic assist characteristic to the modified assist characteristic on the basis of the steering torque; and a motor driving section which drives the electric motor on the basis of the motor driving target value.