Electric power steering control apparatus for motor vehicle, filters steering shaft reaction torque signal by low-pass filter operation whose time constant is determined according to detected vehicle speed and motor rotation speed

摘要

A road surface reaction torque detecting unit outputs road surface reaction torque estimation value to be used to control assist torque by filtering steering shaft reaction torque signal by low-pass filter operation. Time constant of low pass filter operation is determined according to detected vehicle speed and detected motor rotation speed. A vehicle speed detecting unit detects the vehicle speed. A motor speed detecting unit detects the rotation speed of an electric motor. A steering shaft reaction torque signal outputting unit outputs steering shaft reaction torque signal that corresponds to steering shaft reaction torque acting on a steering shaft.