采用分数槽的磁浮列车电磁力波动抑制方法

Electromagnetic force undulation restraining method in MLV using fractional slot

针对常导型高速磁浮列车用直线同步电机的电磁力波动问题,分析导致电磁力波动的原因,提出一种基于分数槽理论来抑制电磁力波动的方法,分析直线同步电机不等极距结构设计对谐波电动势和齿槽力的影响。分析结果表明:采用合适的不等极距设计可以抑制谐波电动势和齿槽力,从而达到抑制电磁力波动的目的。给出一个基于等效极对数的定子和动子极距最优化选择公式,采用有限元仿真方法对不等极距直线同步电机电磁力波动进行了仿真研究。仿真结果表明:电磁力波动得到了较好的抑制效果,推力最大波动从35%减小到5%,悬浮力最大波动从6%减小到0.13%。

The electromagnetic suspension（EMS） high speed magnetic levitation vehicle（MLV） uses the long stator linear synchronous motor（LSM） for suspending and driving,but LSM has much electromagnetic force undulation.For solving this problem,an electromagnetic force undulation restraining method based on fractional slot theory is applied.The influence of LSM unequal polar distance to harmonic electromotive force（EMF） and cogging force was analyzed.The analyzing results show the appropriate unequal polar distance design can restrain harmonic EMF and cogging force,consequently restrain electromagnetic force undulation.Based on equivalent polar number,a formula used for optimal polar distance choosing is presented.The unequal polar distance LSM electromagnetic force undulation simulation was conducted using finite element method.The simulation results show the electromagnetic force undulation restraining method in the paper is valid,the maximum thrust undulation is reduced form 35% to 5%,and the maximum suspension force undulation is form 6% to 0.13%.