Device for detecting a deviating from the standard engine state

摘要

An identification is made of an abnormal condition in a motor due to an influence of a disturbance voltage, without addition of hardware, by estimating the disturbance voltage based on a target voltage and actual current flowing in the motor. An apparatus for detecting the abnormal condition of a motor in an electric power steering apparatus includes a motor current detecting unit for detecting an actual current flowing through the motor; a feedback controlling unit for feedback-controlling a target voltage value that gives the motor a driving command in accordance with the deviation of the actual current from an input target current; an abnormal voltage estimating unit for, based on the target voltage and the actual current, estimating an abnormal voltage estimation value corresponding to a voltage indicating an abnormal condition of the motor; and a motor abnormality judging unit for judging abnormality of the motor based on a comparison of the abnormal voltage estimation value with an abnormal voltage value previously stored.