THE APPLICATION OF HALBACH CYLINDERS TO BRUSHLESS AC SERVO MOTORS

Halbach cylinders are applied to brushless ac servo motors. It is show n that a sinusoidal back-emf waveform and a low cogging torque can be achieved without recourse to conventional design features such as dist ributed windings and/or stator/rotor skew. A technique for imparting a multipole Halbach magnetization distribution on an isotropic permanen t magnet cylinder is described, and it is shown that the torque capabi lity of a Halbach ac servo motor can be up to 33% higher than conventi onal brushless permanent magnet ac motors.