Patent ID: 7742858
Filing Date: 2010-06-22
Classification: B62D

Abstract:
1. An electric power steering apparatus for driving an electric motor based on a steering torque applied to an operation member for steering a vehicle, and for transmitting a driving force produced by the electric motor to a steering mechanism to perform steering assist, the electric power steering apparatus comprising: a steering torque detecting section configured to detect the steering torque; a steering state judging section configured to determine whether a forward stroke steering that steers the operation member away from a steering angle midpoint is performed; a motor controlling section configured to control a driving of the electric motor, based on the steering torque detected by the steering torque detecting section; and a phase compensating sections provided in the motor controlling section for performing phase compensation, such that, when the forward stroke steering is not performed according to the steering state judging section, a gain in a predetermined frequency band in frequency response characteristics of the phase compensation is lower than gains in frequency bands lower and higher than the predetermined frequency band, and is lower than a gain in the predetermined frequency band when the forward stroke steering is performed.