Influence of magnetization on performance of SPM machine with 3rd harmonic injected rotor

The influence of magnetization on the electromagnetic performance in the surface-mounted permanent magnet (SPM) machine with sinusoidal+3rd harmonic shaped rotor is investigated in this paper. The flux density, cogging torque, phase back-EMF, torque and loss are analyzed by finite element (FE) method. The differences of electromagnetic performance between the machines with parallel and radial magnetization manners are illustrated. It is found that the machine with parallel magnetization can produce high torque but also accompanied by high torque ripple compared to that with radial magnetization.