IMPROVEMENTS RELATING TO ELECTRICAL POWER ASSISTED STEERING SYSTEMS

摘要

An electric power assisted steering system comprises a motor adapted to apply an assistance torque to a portion of a steering shaft in response to a motor drive signal from a drive circuit, in which the motor comprises a synchronous wound field motor of the kind comprising a stator and a rotor, in which the rotor includes at least one pole and at least one coil winding associated with the pole and the stator comprises a number of phase windings, and in which the drive circuit which is configured to provide current in the coils of the stator and rotor during operation of the motor.