| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power steering device which generates no torque ripple even when an offset current generated on a current detector varies by a temperature variation or the like during the action, and by which a steering feeling without a feeling of congruity is obtained. SOLUTION: A duty ratio of a PWM signal when an ignition switch is turned on is held. During the action of a motor 6, whether a target current value to be made to flow to the motor 6 is not more than a specified value, and also, whether a motor angular speed is not more than a specified speed are judged. When the applicable conditions continue for a specified period of time, the motor 6 is driven by the held duty ratio. In this case, the offset value is updated by a detected current value which is detected by the current detector. Therefore, even when the offset current varies, the offset value is updated at any time. Thus, the torque ripple is prevented from occurring, and a driver obtains a steering feeling without a feeling of congruity. COPYRIGHT: (C)2005,JPO&NCIPI |
