volume | PIER Journals

Abstract

In order to reduce the use of rare-earth materials and solve the problem of rising manufacturing costs of permanent magnet motors due to higher rare-earth prices, this paper proposes an asymmetric segmented less-rare-earth permanent magnet motor (ASLREPMM), which combines NdFeB permanent magnets with ferrite permanent magnets to form a common excitation source. In order to efficiently design the parameters of this motor, an optimization strategy of sensitivity stratification and multi-objective optimization is proposed, with output torque, torque pulsation, cogging torque and peak air-gap magnet density as the optimization objectives, and multi-objective optimization is carried out on the optimization variables with high sensitivity. Compared with the V-type permanent magnet motor (V-type PMM), the cogging torque of the optimized ASLREPMM is decreased by 49.67%, torque pulsation decreased by 10.77%, peak air-gap magnetic density increased by 0.051 T, and the total amount of NdFeB material decreased by 2184 mm³. The reasonableness of the structural design and the effectiveness of the optimization of the ASLREPMM are verified through experiments.

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Mr. Lu Zhang

Dr. Jinbin Xu

Dr. Chen Qi