少稀土组合磁极Halbach永磁同步电机优化设计

针对稀土永磁同步电机(PMSM)对稀土永磁材料依赖性大的问题，提出一种少稀土组合磁极Halbach PMSM,永磁体采用Halbach充磁方式。阐述了该电机新型转子的磁钢结构，其中主磁极由双层永磁体组成，上层磁钢为钕铁硼永磁材料，下层磁钢为铁氧体永磁材料，辅磁极磁钢也为铁氧体永磁材料。以电磁转矩、转矩脉动和齿槽转矩为优化标准，对电机每极永磁体块数、充磁角度、永磁体材料和永磁体厚度等电机参数进行优化。采用定子斜槽结构降低齿槽转矩。优化后的少稀土组合磁极PMSM在保证转矩性能的情况下，减少了永磁体用量，降低了电机成本。最后通过有限元法分析该电机在空载和额定负载下的特性，验证了该电机设计的合理性。

Optimization Design of Less-Rare-Earth Halbach Permanent Magnet Synchronous Motor with Module Poles

The rare earth permanent magnet synchronous motor (PMSM) depends much on the rare earth permanent magnet materials. In order to solve this problem, a less rare earth PMSM with Halbach array and module poles is proposed. The new structure of the rotor magnetic steel of the motor is described. The main pole of the rotor magnet is composed of two layers of permanent magnets, the outer magnet is made of NdFeB permanent magnet material, the inner magnet is made of ferrite permanent magnet material, and the auxiliary pole magnet is also ferrite permanent magnet material. The electromagnetic torque, the torque ripple and the cogging torque are regarded as optimization criteria. The motor parameters are optimized by using the number of permanent magnets per pole, magnetization angle, permanent magnet material and permanent magnet thickness. A chute type stator structure is used to reduce cogging torque. The optimized less rare earth PMSM with module poles reduces the amounts of permanent magnets and reduces the cost of motor while ensuring the torque performance. Finally, the finite element method is used to analyze the performances under the conditions of no load and rated load operation, and to verify the validity and reasonableness of the proposed motor.