| 摘要 |
PROBLEM TO BE SOLVED: To improve reliability and safety by judging whether the direction of auxiliary steering effort output from an induction motor is normal or not. SOLUTION: A control unit 13 computes a target torque instruction value Ts in response to a steering torque signal To from an driver and a motor driving circuit 16 outputs a three-phase drive signal corresponding to the target torque instruction value Ts. Thus, the induction motor 5 generates auxiliary steering effort corresponding to the steering effort of the driver. A motor rotating direction judgement part 24 detects the direction of the steering effort using the steering torque signal To, determines the direction of the auxiliary steering effort in order in which actual currents iU, iV, iW detected by current sensors 10, 11, 12 are output, and judges the direction of the auxiliary steering effort compared with the direction of the steering effort. Judgement of whether the direction of the auxiliary steering effort of the induction motor 5 is the same as the direction of the steering effort or not can be made, improving reliability and safety. |
