To enhance the accuracy of motor control by a compact steering system arrangement optimized in cost.
In the electric power assisted steering system capable of applying assist torque to the angular displacement of the wheel of an automobile, the torque is applied by an electronically rectifying motor 2 having P phases and N pairs of poles. The system further comprises a device for controlling the motor 2. The control device comprises a circular mutipolar encoder 17 having a main mutipolar track 17a, and a mutipolar rectification track 17b composed of magnetically singular regions 17b1-17b6 distributed at constant angles, a fixed sensor 19 capable of supplying square digital signals A and B of quadrature phases and 2*P*N pulse signals C per revolution of a rotor 3, a circuit 20 for rectifying the current by the phase winding of the motor 2, and a control circuit 21 for the rectifying circuit 20.
NICOT CHRISTOPHE
FRIZ ACHIM
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