永磁直线同步电机空载反电动势和推力的解析计算

Analytical Calculation of No-Load Eletromotive Force and Thrust in Permanent Magnet Linear Synchronous Motors

针对目前永磁直线同步电机(PMLSM)磁场解析模型的复杂性,为了提高解析模型的计算效率,采用改进的二维气隙相对磁导函数,以计算考虑齿槽效应时电机的空载反电动势和推力。首先建立无槽PMLSM解析模型,提出改进的二维气隙相对磁导函数以解决切向气隙相对磁导分布,根据有槽PMLSM解析模型计算出电机开槽时的气隙磁通密度法向和切向分布。基于磁场解析模型得到不同极槽配合下电机的空载反电动势和推力,探讨极槽配合、不同槽宽及绕组分布对电磁参数的影响,并用有限元法证明了解析法的正确性。该文提出的方法在保证准确度的前提下,适用于整数槽、分数槽绕组PMLSM的电磁参数计算,具有求解方法简便、计算量小、通用性好的特点,有利于电机的快速电磁设计和性能优化。

In view of the complexity of the current magnetic field analytical model of permanent magnet linear synchronous motors(PMLSMs),and in order to improve the computational efficiency of the analytical model,an improved two-dimensional(2D)relative permeance function is used to calculate the no-load eletromotive force(EMF)and thrust of the PMLSM when the slotting effect is considered.The analytical model of slotless PMLSM is established firstly,and an improved 2D relative permeance function is given to solve the tangential relative permeance distribution.According to the analytical model of slotted PMLSM,the normal and tangential magnetic densities are calculated.Based on the analytical model,the no-load EMF and thrust of the PMLSM with different slot-pole combinations are obtained,and the influence of slot-pole combinations,slot width and winding distribution on the electromagnetic parameters is discussed.The accuracy of the analytical method is proved by the finite element method(FEM).Under the condition of accuracy,the proposed method is suitable for the electromagnetic parameter calculation of integral slot and fractional slot PMLSM.It has the characteristics of simple and convenient,low computational burden and good universality,which is conducive to the rapid electromagnetic design and performance optimization of the motor.