新型高品质永磁电机电磁振动关键问题研究

In recent years, many new permanent magnet (PM) machines are developed and promoted for application due to their high quality. These machines are different from conventional induction machines or electrically excited synchronous machines in the aspects of mechanical structure and the mechanism of electromagnetic energy conversion. Therefore, those research achievements based on conventional electrical machines are no longer sufficient to analyze the PM machines with new topologies. This project is intended to study the electromagnetic vibration characteristics of those new PM machines under the interaction of complex electromagnetic force and the slotted structure. .The interaction mechanism between the slotted structure and the air-gap spatial force harmonics will be studied in detail, and the spatial modulation effect of the slotted structure on the machine vibration will be revealed, which will explain the non-negligible effect of high spatial order air-gap force harmonics. This project will also research the slot leakage flux and the corresponding electromagnetic force and their interaction with the mechanical structure. An accurate and efficient calculation method will be proposed to calculate the electromagnetic force in the slots, which is rarely considered in the correlative literatures. An equivalent mechanical model is also to be established, based on which the formula to calculate machine vibration will be derived. Finally, a semi-analytical model, which takes the complex electromagnetic force and slotted structure into consideration, will be established for electromagnetic vibration and noise calculation for PM machines. The semi-analytical model will lay a theoretical foundation for the analysis, optimization and suppression of vibration and noise for PM machines. Based on this project, the application of high quality PM machines with new topologies in national defense and military industry and high-end equipment manufacturing industries will be further promoted.

近年来，许多新型高品质永磁电机不断涌现和推广应用，其电磁场分布、作用机理以及结构机械特性等均与常规电机有所不同，现有的常规电机振动噪声研究成果已不足以对这些电机进行深入的分析。本项目拟针对这些新型永磁电机拓扑，开展复杂多维空间电磁力与齿槽结构相互作用下电机电磁振动关键问题的研究。深入研究电机齿槽结构与气隙电磁力空间谐波的相互作用机理，揭示齿槽结构的空间调制效应以及气隙高阶空间力波对振动的显著影响；研究电机槽内漏磁场所引入电磁力的三维空间分布特性及作用特点，建立电机三维机械结构的等效力学模型，推导其在复杂空间电磁力作用下的变形计算公式；最终，以削弱电机的电磁振动为目标，开发一套综合考虑多维空间电磁力波、齿槽结构空间调制效应的电机振动噪声半解析计算模型，为永磁电机振动噪声的准确分析、快速优化和抑制奠定坚实的理论基础，促进新型高品质永磁电机在国防军工、民用高端制造等领域的进一步推广应用。

随着交通电气化的发展，高品质电机在电动汽车、轨道牵引、船舶推进、航空航天等领域被广泛关注，而振动噪声是高性能电机产品的重要技术指标。气隙电磁力是电机振动噪声产生的主要原因，然而，一直以来众多学者对电机电磁力的研究主要关注其气隙径向力的时间、空间谐波，对切向力成分以及电磁力与结构之间的相互作用却关注不多，从而导致对电机电磁振动的分析预测难以达到很高的精度，也制约了电机电磁振动的优化抑制。本项目重点围绕电机在复杂电磁力作用下的电磁振动的准确分析开展研究工作：首先，研究了气隙电磁力波与电枢齿槽结构之间的相互作用机理，发现并完善的电磁力与齿槽之间的调制效应；其次，研究了切向电磁力波对电机径向振动的影响，并重点分析了电机中切向、径向力之间的空间叠加方法；在上述研究基础上，本项目提出了计及电机齿槽调制效应及气隙切向力作用的电磁振动高精度半解析算法；此外，针对逆变器供电中高频电流谐波产生的高频振动问题，还提出了基于频率映射的高频振动快速计算方法，有效解决了直接有限元仿真效率低的问题；最后，基于上述研究成果，自主开发了一款电机电磁振动噪声半解析预测与分析软件，并已成功应用于电动汽车电驱动领域，有效提升了驱动电机NVH开发效率。