【目的】针对刮板输送机用稀土永磁电机存在永磁体成本高、气隙磁场谐波含量较高以及高温抗退磁能力差等问题,本文设计一种由铁氧体和钕铁硼共同励磁的混合磁极低速永磁同步电机(PMSM),利用铁氧体永磁成本低、高温抗退磁能力强等优点改善上述问题。【方法】首先对PMSM进行电磁设计,确定其基本参数。为提升永磁材料利用率,在控制永磁体用量相同的条件下,设计五种不同转子结构并进行对比分析,选取转矩输出能力最强的转子结构。在此基础上,设计三种不同磁路结构的混合磁极方案进行对比分析。最后利用有限元软件,对最终方案进行电磁性能分析、温度场校核以及高温抗退磁能力分析,验证混合磁极方案的有效性。【结果】与传统稀土永磁电机相比,混合磁极转子结构在保证额定转矩的前提下,永磁体成本降低了15.5%,转矩脉动降低了16.7%,同时显著提升了高温抗退磁能力。【结论】混合磁极转子结构在降低永磁体成本、优化电机性能以及增强高温稳定性方面效果显著,为刮板输送机实现节能减排和降低维护需求提供了可靠的技术支持。

[Objective] Aiming at the issues of high permanent magnet cost, excessive air-gap magnetic field harmonics, and poor high-temperature demagnetization resistance in rare-earth permanent magnet motors for scraper conveyors, this paper proposes a hybrid-pole low-speed permanent magnet synchronous motor (PMSM) excited by both ferrite and NdFeB. The design leverages the advantages of ferrite magnets, such as low cost and strong high-temperature demagnetization resistance, to address these problems. [Methods] The electromagnetic design of the PMSM was first conducted to determine its fundamental parameters. To enhance permanent magnet material utilization, five distinct rotor structures were designed and comparatively analyzed under identical magnet usage conditions, from which the configuration with optimal torque output capability was selected. Subsequently, three hybrid-pole magnetic circuit designs were developed for comparative evaluation. Finally, finite element analysis software was employed to perform comprehensive assessments of the finalized design, including electromagnetic performance analysis, temperature field verification, and high-temperature demagnetization resistance evaluation, thereby validating the effectiveness of the hybrid-pole solution. [Results] Compared with traditional rare-earth permanent magnet motors, the hybrid-pole rotor structure reduced the permanent magnet cost by 15.5% while maintaining the rated torque, decreased the torque ripple by 16.7%, and significantly enhanced the high-temperature demagnetization resistance. [Conclusion] The hybrid-pole rotor structure demonstrates remarkable effectiveness in reducing permanent magnet costs, optimizing motor performance, and improving high-temperature stability, providing reliable technical support for energy-saving, emission reduction, and reduced maintenance requirements in scraper conveyors.

辽宁省自然科学基金联合基金(2023-MSLH-245)