ELECTRIC MOTOR AND METHOD OF BRAKING USING AN ELECTRIC MOTOR

摘要

An electric motor comprising a stator having a plurality of coils, a rotor having a plurality of permanent magnets and a controller that is arranged to provide a voltage to the plurality of coils to generate a current through the coils that is defined by a stator current vector, wherein the controller is arranged to freeze the angle of the stator current vector unless the angle between the stator current vector and a rotor magnetic flux vector associated with the rotor magnets exceeds a predetermined value, wherein if the predetermined value is exceeded the controller is arranged to synchronised the movement of the stator current vector to the movement of the rotor magnetic flux vector.