齿槽转矩利用型低脉动虚拟极辐向永磁电机设计机理

The spoke-type permanent magnet (PM) motor has the advantages of low cost, high efficiency and high torque density. It has become a research hotspot in the field of electric vehicle. To overcome the demerit of high torque ripple of the existing spoke-type PM motor, a series of low torque ripple spoke-type PM motors with virtual magnetic poles are proposed. Based on the plasticity of the virtual magnetic poles, the asymmetrical and shifted poles are adopted to reduce the torque ripple from the aspect that the torque ripple components are simultaneously suppressed when the cogging torque, PM torque ripple and reluctance torque ripple are regarded as a whole. Furthermore, on the basis of accurately separating the torque ripple components, the cogging torque is used to cancel the PM torque ripple and the reluctance torque ripple, realizing cogging torque utilization low torque ripple spoke-type PM motor design by mutually suppressing the ripple components. Considering the effects of tolerance, machining error and PM parameters on the torque performance of the motor, the design method of motor parameters with high robust is investigated. Meanwhile, the multi-physical field simulation models of the new motor topologies will be built to ensure the feasibility of motor parameter design and to compare the advantages and disadvantages of different low torque ripple design methods. An experimental platform will be built to analyze and evaluate the comprehensive performance of the motor system. The basic scientific problems can be refined to reveal the torque ripple suppression mechanism and the general design method of the proposed motor, laying theoretical and experimental foundation for its application.

辐向永磁电机在兼具高效率和高转矩密度的同时还具有低成本的优势，已成为电动汽车领域的研究热点。克服现有辐向型永磁电机高转矩脉动的弊端，提出一类具有虚拟极的低脉动辐向永磁电机。利用虚拟极的可塑性，采用非对称、偏移极设计，将齿槽转矩、永磁转矩脉动和磁阻转矩脉动视作一个整体，从转矩脉动各分量同时抑制的角度来实现转矩脉动的降低；进一步地，在精确分离各转矩脉动分量的基础上，利用齿槽转矩来抵消永磁转矩脉动和磁阻转矩脉动，从各分量相互抑制的角度实现齿槽转矩利用型低脉动辐向永磁电机设计；考虑公差、加工误差及永磁体参数各样性对电机转矩性能的影响，研究高鲁棒性的电机参数设计方法；构建新型电机拓扑的多物理场仿真模型，保障电机参数设计可行性并对比分析不同低脉动设计方法的优劣；搭建实验平台，进行电机系统综合性能的分析与评估；提炼基础科学问题，揭示新型电机的转矩脉动抑制机理和一般性设计方法，为其应用奠定理论和实验基础。

辐向永磁电机在兼具高效率和高转矩密度的同时还具有低成本的优势，已成为电动汽车领域的研究热点。本项目研究了多种高转矩性能的辐向型永磁电机。针对该类电机在设计过程中很难兼顾平均转矩与转矩脉动的问题，在总结分析现有该类电机特点的基础上，提出多种新型辐向永磁电机结构。包括整数槽和分数槽辐向永磁电机、对辅助凸极进行修型的辐向永磁电机、低永磁体用量的混合转子辐向永磁电机以及倒T型辐向永磁电机。接着，基于智能优化算法对提出的电机进行多目标优化设计，优化后电机的转矩和转矩脉动都得到了改善。然后分析该类电机的转矩脉动抑制方法，揭示转矩脉动抑制原理。最后，制造加工了多个实验样机，测试了样机的电磁特性及其他性能，本项目从电机本体结构、设计与优化、有限元对比分析、仿真与实验验证这些方面对所提出的电机进行了系统性的分析与设计。所提出的各类新型辐向永磁电机能克服传统辐向永磁电机转矩脉动高的弊端，为辐向永磁电机在交通运输、航空航天、伺服控制等领域的应用奠定理论基础和实验基础。