旁路分流式永磁体技术研究

Technology of bypass-shunting-magnet

提出可提升永磁体抗去磁能力的旁路分流式永磁体技术。该技术基于内嵌式永磁电机中永磁体边角比中心区域去磁风险更高的特点,利用永磁体表面局部镍镀层作为永磁体导磁旁路,分流其退磁磁场,由此抑制永磁体边角处工作点的下降,提升了永磁体抗退磁能力。通过抗退磁机理分析及应用实例的有限元计算结果分析并验证了旁路分流式永磁体抗退磁的可能性及有效性。应用田口法对某款电机永磁体的厚度、镀层厚度、镀层宽度进行比较分析,得出这些关键参数对转矩、转矩脉动、永磁体退磁工作点等性能指标的影响及最优组合;最后基于全面的有限元计算分析,进一步验证并完善了之前的分析结论及旁路分流式永磁体的参数设计规律。

The anti-demagnetization technology of bypass-shunting-magnet was proposed.It′s based on the feature of partial demagnetization in interior permanent magnet(IPM)motor which has higher risk of demagnetization in the corner area compared with the center.Nickel-plate was applied at topical surface of magnet as by-pass flux paths to shunt demagnetizing flux,thereby the lowest operating point of the magnet is elevated and the anti-demagnetization ability of motor is enhanced consequently.The possibility and effectiveness of anti-demagnetization technology of bypass-shunting-magnet was analyzed and verified through mechanism analysis and FEA.Several combinations of parameters such as magnet thickness,plating thickness and plating width were analyzed through Taguchi method,then the optimal choice was selected and the influence of these parameters to the torque,torque ripple,working point of magnet and other performance were concluded.At last,based on further FEA results,the conclusion about parameter design rule of bypass-shunting-magnet was verified and improved.