Patent ID: 9610973
Date: 2017-04-04
CPC Classifications: B62D

Claim:
1. A motor-driven power steering apparatus comprising: a steering shaft configured to be rotated in connection with a steering wheel of a vehicle; a pinion shaft configured to apply driving force to a rack shaft by rotating with respect to the rack shaft turning a turning wheel; a detector configured to detect a torque between the steering shaft and the pinion shaft; an electric motor configured to apply driving force to the rack shaft; a base current calculator configured to calculate a base current, which is a base for a target current to be supplied to the electric motor, based on a detected torque detected by the detector; a band-pass filter configured to allow a predetermined range of frequency components of the detected torque detected by the detector to pass through the band-pass filter; a base suppression current calculator configured to calculate a base suppression current, which is a base for a suppression current required to suppress a disturbance torque transmitted from the turning wheel to the steering wheel, based on a passing torque which is the detected torque after passing through the band-pass filter; a suppression current calculator configured to calculate the suppression current by correcting the base suppression current, which is calculated by the base suppression current calculator, according to magnitude of amplitude of the passing torque; and a target current determiner configured to determine the target current based on the base current calculated by the base current calculator and the suppression current calculated by the suppression current calculator.