Electric power steering apparatus

Abstract

[Problem] An object of the present invention is to provide an electric power steering apparatus that easily obtains equivalent steering torques to vehicle driving information such as a steering angle without being affected by a road surface state and aging-changes of mechanism characteristics of a steering system. [Means for Solving the Problem] The electric power steering apparatus that assist-controls a steering system, comprises: a target steering torque generating section to generate a target steering torque based on vehicle driving information, a converting section to convert the target steering torque into a target torsional angle, and a torsional angle control section to calculate the current command value based on the target torsional angle, a torsional angle of the torsion bar and a motor angular velocity; and the torsional angle control section comprises a torsional angle feedback compensating section to output a target torsional angular velocity corresponding to a deviation between the target torsional angle and the torsional angle, a velocity control section to output the current command value based on the target torsional angular velocity, and a stabilization compensating section to perform feedback to the current command value by setting a transfer function to at least one of angle relation information.