长定子直线同步电机齿槽效应的计算与影响

Calculation and Influences of Cogging Effects in Long-Stator Linear Synchronous Motor

采用解析算法计算常导高速磁悬浮列车长定子直线同步电机(LSM)的电磁性能,计算模型考虑了长定子的齿槽结构,在LSM的一对极下,沿运动方向建立磁导率方程和励磁磁动势方程,然后根据傅里叶级数展开法求解方程,得到气隙磁通密度沿运动方向的分布,显示了齿槽效应的影响。之后,基于有限元模型计算不同运行速度下齿槽效应对力特性、励磁绕组感应电动势与铁心损耗的影响。结果发现,齿槽效应会导致推力波动增大,励磁绕组中产生感应电压,励磁铁心损耗增大,且随着速度的增加这些影响越明显。

The analytical method was applied to compute the electromagnetic performance of linear synchronous motors for high speed Maglev train.The model took the primary salient structure of the primary into account,and one pair of poles of the motor was selected for mathematical modeling.Taking the magnetic density in air-gap as variable,the magnetic permeability and excitation magneto-motive force function along the direction of motion was established.The distribution of the magnetic density in air-gap and the winding coefficient were obtained by solving the Fourier transform equations.Based on the analytical model,the effect of cogging on force characteristics,induced electromotive force in excitation windings,and iron loss at different velocity were calculated by finite element method.The study found that the cogging effect can cause large force ripples,induced voltage in the excitation windings,and bigger iron losses in the magnetic poles,especially at high speeds.