| 摘要 |
<p>PROBLEM TO BE SOLVED: To surely prevent the deterioration of the steering performance by lowering an electric current command value calculated by a current control means, by a current command correcting means, when a steering system reaches the maximum steering angle, and the steering torque is above a specific value. SOLUTION: When the load is applied to a steering wheel in a condition that a steering system reaches the maximum steering angle in the forward and backward driving at a low speed for parking own car into the garage or the like, a steering torque detection value T is increased, and a motor target current command value i* is over a set value is (S18), the load of a steering assistant motor is suddenly increased, and the rotation thereof is stopped for regulating the steering over the maximum turning angle of the steering system. That is, when the load of the motor is increased, the back electromotive force is lowered and the steering angle speedωis set '0'. Then a specific current valueΔi is subtracted from the present target current command value i* (S19), a duty ratio D is suppressed to a smaller value (S20), and the electric current to be supplied to the steering assistant motor is limited. Whereby the exoegic of the motor can be surely inhibited.</p> |
