关键词: 内置式永磁同步电机, 对称偏心磁障, 多目标优化, 齿槽转矩, 转矩脉动

Abstract: To improve the torque output of the interior permanent magnet synchronous motor ( IPMSM) and effectively reduce the cogging torque and torque ripple,this paper proposes a new type of interior permanent magnet rotor structure with symmetric and eccentric magnetic barrier at the q-axis to form a gradient iron bridge for controlling the airgap magnetic field distribution,as an alternative to the conventional interior permanent magnet rotor structure with non-uniform airgap. The sensitivity analysis is conducted on the main parameters of the new structure,and key parameters with significant impact on performance is identified and selected;a Gaussian regression surrogate model is built and a multi-objective genetic algorithm is applied to optimize parameters,resulting in an optimal motor with the new structure;the optimal motor’ s electromagnetic torque output performance is compared with the conventional rotor pole cutting motor. The simulation results show that the motor with new rotor structure can not only achieve no-load airgap magnetic field distribution as good as that of the one with non-uniform airgap,but also has lower cogging torque and significantly reduced torque ripple,and can produce higher noload fundamental magnetic density and larger electromagnetic torque.

Key words: interior permanent magnet synchronous motor, symmetrical eccentric magnetic barrier, multi-objective optimization;cogging torque;torque ripple