基于力学及电学性能的汽车发电机转子爪极尺寸优化选择

Claw Rotor Size Selection of Automobile Generator Based on Mechanical Property and Electric Property

将汽车发电机转子梯形爪极等效为悬臂梁模型,应用基本的气隙磁场理论和材料力学理论,考虑转子爪极所受离心力及气隙磁场径向力,分析变化参数下梯形爪极的变形趋势及规律。利用Ansys软件建立三维有限元结构力学分析模型,得出基本的结构位移变形分布图。着重求导了主波磁场所产生的径向力及转子离心力,然后在此基础上分析比较不同爪极厚度轴向角β时爪极最大挠度的大小。利用Maxwell 3D软件建立三维有限元电磁场分析模型,比较不同β角时的电势波形及效率的变化。在尽可能减少爪极挠曲形变对汽车发电机气隙磁导的影响的同时,保证发电机良好的输出性能,从而对发电机转子的爪极尺寸进行优化设计。该设计与优化方法可为高性能汽车发电机爪极设计提供理论指导。

The automobile generator rotor＇s trapezoid claw deforming trend and rule in different parameters was ana-lyzed. The generator＇s trapezoid claw was equaled to the cantilever rotor model. The basic air-gap magnetic field theory andthe material mechanics theory were applied,and the rotor＇s centrifugal force and the air-gap magnetic field radial force wereconsidered. The basic structural displacement deformation distribution graph was gained,and the 3D finite element structuremechanics analysis model was built with Ansys. The radial force generated by the magnetic field＇s main wave and the rotor＇s centrifugal force were emphatically deduced. The size of the claw pole＇s maximum deflection with different claw pole thick-ness axial angle 茁structures were analyzed and compared. The three dimensional finite element analysis of electromagneticfield model was built with Maxwell 3D to compare the changes of potential wave form and the efficiency with different angle β. The generator＇s claw pole size was optimized,when the influence of claw pole deformation to the air gap magnetic conduc-tivity is reduced and the claw pole＇s good electrical performance guaranteed. The design and optimization method discussedin this paper will provide theoretical guidance for claw pole design of high performance alternator.