Patent ID: 8924080

Claim:
An electric power steering apparatus for controlling an electric motor depending on a steering torque applied to an operating member, and transmitting a drive force generated by the electric motor to a steering mechanism to assist in steering a vehicle, comprising: a steering torque sensor for detecting the steering torque; a phase compensator for phase-compensating a torque signal output by the steering torque sensor; and an assistive current determiner for determining an assistive current that flows through the electric motor based on at least the torque signal, which is phase-compensated by the phase compensator, wherein the phase compensator performs a frequency shifting process for frequency-shifting both a pole of a minimum frequency and a zero point of a minimum frequency toward higher frequencies, or for frequency-shifting both a pole of a minimum frequency and a zero point of a minimum frequency toward lower frequencies, for thereby changing a compensation frequency band that is compensated by the phase compensator.