Development of Magnet Structure Optimization on Achieving the Cogging Torque Reduction in Permanent Magnet Machine

This paper dealt with the magnet structure optimization of integral slot numbers on achieving the cogging torque reduction of the permanent magnet machine. The permanent magnet machines have been widely used in many applications for the last few years. The cogging torque effects to reduce permanent magnet machine performance leads to decrease the effectiveness of the permanent magnet machine function. Cogging torque can be concluded as one of the important issues in permanent magnet machine applications and should be overcome. In this study, a-two steps of slotting in magnet edge and pole arc optimization in magnet edge have been combined in order to minimize the cogging torque of the proposed machine. An integral slot number of permanent magnet machines with 24 slot / 8 pole structure has been selected in this work. The cogging torque reduction technique of the proposed machine was analyzed and validated using finite element method magnetics. The advantages of the cogging technique reduction technique proposed in this study are the cogging torque can be reduced significantly around 99.98 % compared with the initial structure.