Influence of Shape and Arrangement of Permanent Magnets on Characteristics of Outer-Rotor IPM Motor

Abstract

　In this paper, we analyzed the magnetic field of an outer-rotor IPM motor using the three-dimensional parallel finite element method in order to investigate the influence of the shape and the arrangement of the permanent magnets. We clarified that providing a flux barrier between the divided magnets is able to reduce the leakage magnetic flux between the divided magnets and to prevent the torque from decreasing. Furthermore, it was clarified that the torque ripple can be reduced while maintaining the average torque by changing the arrangement of the magnets.