Comparison of Electromagnetic and Vibration Performances of Dual Three-Phase and Multiphase SPM Motors

This paper compares the electromagnetic and vibroacoustic performances of the dual three-phase and the five-phase surface permanent magnet motors when changing a teeth pitch of stator core. 3D-finite element analysis indicates that the five-phase motor exhibited superior performance compared to the dual three-phase motor in terms of torque and vibration performance, while the dual three-phase motor had advantageous of the efficiency and acoustic noise. Additionally, by injection of third harmonic current to enhance torque performance for the five-phase motor, electromagnetic and vibroacoustic comparison is performed. Although the average torque is increased by approximately 17%, the acoustic noise and vibration is more inferior than that without the harmonic current injection.