| 摘要 |
<p>An electrical power-assisted steering system is disclosed comprising an electric motor (1) connected through a gearbox (34) to act on a steering mechanism of the vehicle, the electric motor (1) having a plurality of phase windings connected to a star point and switching means provided in at least one phase of the motor, the switching means being movable between a closed position in which current is able to flow in the phase windings, and an open position which prevents current flowing in a respective phase winding (40). The system incorporates a safety circuit (20) operative when a fault develops to smooth out the transition between the presence (24) and absence (23) of servo support in assisting and not assisting by providing a prescribed period of damped operation (21) as part of a shut-down phase. <IMAGE></p> |
