轴向充磁圆筒型永磁直线同步电机气隙磁场解析计算

Analytical Calculation of Air Gap Magnetic Field in Axially Magnetized Tubular Permanent Magnet Linear Synchronous Motor

介绍了一种基于许-克变换法的轴向充磁结构圆筒型永磁直线同步电机(TPMLSM)气隙磁场解析计算方法。首先采用许-克变换法计算出无齿槽时电机的气隙磁场;然后利用许-克变换法求取初级铁心开槽时的气隙相对比磁导函数,分析铁心开槽对气隙磁场的影响;最后通过无齿槽时的气隙磁场与有齿槽时的气隙磁场相对比磁导函数得到有齿槽时电机的气隙磁场分布。同时给出了该种充磁结构TPMLSM气隙磁场解析计算表达式,并以1台36/12极槽配合轴向充磁TPMLSM样机进行试验。试验结果证明空载气隙磁场的有限元分析值与解析值较吻合,空载电动势(EMF)计算值、试验测试值、有限元分析值一致。

An analytical calculation method of air gap magnetic field in axially magnetized tubular permanent magnet linear synchronous motor(TPMLSM) based on Schwarz-Christoffel(S-C) transformation method was introduced. Firstly, the air gap magnetic field distribution of the slotless motor was analytically calculated based on S-C transformation method. Then, the air gap relative ratio permeance function of slotted motor was obtained based on S-C transformation to consider the effect of stator core slots. Finally, the air gap magnetic field distribution of the slotted motor was obtained by the basic air gap magnetic field of the slotless motor and the air gap relative ratio permeance function. The analytical formulas of the air gap magnetic field distribution were derived for the axially magnetized TPMLSM. Experiment was carried out using a 36-slot 12-pole axially magnetized TPMLSM. The predicted air gap magnetic field distribution matched the corresponding finite element result, and the measured no-load electromotive force(EMF) of the prototype was also consistent with the analytical and the finite element value, so the validity of the proposed method was proved.