| 摘要 |
PROBLEM TO BE SOLVED: To dispense with application of torque in the steering wheel returning direction required of a driver when steering is carried out within a low tire road surface reaction torque range in a conventional electric power steering control device. SOLUTION: First road surface reaction torque is estimated from driver's steering torque detected by means of a steering torque detector 1, a motor acceleration detected by means of a motor acceleration detector 5 and a motor current detected by means of a motor current detector 11, while second road surface reaction torque is estimated from a steering angle detected by means of a steering angle sensor and a vehicle speed detected by means of a vehicle speed detector 14. A first steering wheel returning assisting torque signal and a second steering wheel returning assisting torque signal are computed from the road surface reaction torque, and according to the computed result, torque of a motor 10 is controlled in the direction of returning the steering wheel to its home position. |
