volume | PIER Journals

Abstract

Rare-earth permanent magnet motors are widely used in industrial and civil applications due to their advantages of high efficiency, energy saving, simple structure, etc. However, its development is hindered by escalating raw material costs. The current research focuses on developing high-performance and cost-effective permanent magnet motors with less rare earth. To reduce the large cogging torque of the integer slot 4-pole 36-slot less rare earth combined magnetic poles permanent magnetic synchronous motor (LREH-PMSM), a fractional slot 4-pole 30-slot LREH-PMSM is proposed and optimized. The motor and its parameters are designed, simulated, and analyzed by the finite element method. The effects of these parameters are analyzed on motor torque, torque ripple, efficiency, and material cost. The fractional slot 4-pole 30-slot LREH-PMSM can effectively reduce the cogging torque compared with the integer slot 4-pole 36-slot LREH-PMSM, and its value decreased by 88.28%. Compared with traditional rare-earth permanent magnet synchronous motor (PMSM), it not only has small cogging torque, but also lowers the reliance on rare-earth permanent magnet materials, which in turn lowers the material cost of the motor.

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Dr. Zongyao Li

Dr. Chunyan Li

Dr. Yue Wang