Multi-Objective Optimization of Less-Rare-Earth Interior Permanent Magnet Synchronous Machines Used for Electric Vehicles

The less-rare-earth interior permanent-magnet synchronous machines (LRE-IPMSM), which have the advantages of high electromagnetic performance and low cost, draw more and more attention nowadays in the field of the electric vehicles. The requirements of the machines used for electric vehicles include high torque and high efficiency. Hence, the multi-objective optimization is crucial to LRE-IPMSM. In this paper, firstly, the effects of the permanent magnet (PM) thickness and width on the torque and efficiency are studied. Then, the PM widths are selected as the optimization variables based on the performance analysis. Lastly, the optimized design is obtained by the multi-objective optimization analysis.