| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric power steering device that keeps on applying an assist force with a simple structure even when a torque sensor is abnormal. <P>SOLUTION: An alternative steering torque calculating unit 50 includes a turning angle estimation calculating unit 52 for estimating a turning angle θt on the basis of right and left wheel speeds Wl and Wr in a vehicle, and a pinion angle calculating unit 53 for converting the turning angle θt into a value converted into a rotational angle of a steering shaft on the side of a steering wheel more than a torsion bar, i.e., a pinion angle θp. The alternative steering torque calculating unit 50 calculates alternative steering torque T on the basis of a steering angle θs detected by a steering sensor and the pinion angle θp. Then, a current command calculating unit 45 calculates a current command value I* by using the alternative steering torque T instead of a steering torque τ detected by the torque sensor when the torque sensor is abnormal. <P>COPYRIGHT: (C)2011,JPO&INPIT |
