Permanent Magnet losses Comparisons of Permanent Magnet Vernier Motors With Different Stator Topologies

In this paper, the permanent magnet (PM) losses in the permanent magnet vernier motors (PMVM) with different stator topologies are investigated. Firstly, the compared motor models are proposed and analyzed. Then, the mechanism and calculation model of magnet losses are investigated, and the slot harmonics highlight. Besides, the dimensions of the two motor topologies on the magnet losses are compared and analyzed, including the slot opening and auxiliary slot depth. It can be concluded that the output torque and magnet losses cannot achieved the maximum simultaneously in both topologies. Thus, there should be a tradeoff between the torque and magnet losses. Moreover, a parameter K titled as open slot ratio is proposed to evaluate the relationship among different slot opening width, and the optimized value of K is also suggested. Finally, valuable suggestions are developed for a better design.