多边形组合式永磁直线电机边端力削弱方法

Weakening Method of End Force in Polygon Combined Permanent Magnet Linear Motor

在低速大推力直线驱动领域,针对平板型永磁直线电机体积过大导致电机制造复杂和维护困难的问题,介绍了一种多边形组合式永磁直线同步电机(PCPMLSM)。沿着圆周方向叠片的PCPMLSM减小了涡流效应。利用三维有限元方法(FEM)对1台20极24槽的PCPMLSM进行了分析。针对该结构电机存在的边端力导致电机定位精度受限和推力特性恶化问题,分析了端部磁通不对称造成的单端边端力非周期变化规律,采用与初级铁心交链的磁极数为奇数和偶数时的单端边端力平均值的方式削弱此现象。在此基础上,提出采用优化初级铁心长度和各边的边端齿不等宽错位相结合的方法来削弱边端力。最后通过FEM验证了此方法的有效性。

In response to the issues of complex manufacturing and hard maintenance caused by the large volume flat-type permanent magnet linear motor in the low speed and large thrust linear drive field, a polygon combined permanent magnet linear synchronous motor(PCPMLSM) is described. PCPMLSM laminated along the circumferential direction eliminates eddy current effect. A 20-pole 24-slot PCPMLSM is analyzed by the 3 D finite element method(FEM). Aiming at the problems of limited location accuracy and deterioration of thrust characteristics caused by the end force of the motor with this structure, the non-periodic variation rule of single end force caused by asymmetry of the end flux is studied. This phenomenon is weakened by using the mean value of the single end forces when the number of magnetic poles connected with the primary core is odd and even. On this basis, the method of reducing the end force by combining the optimization of the primary core length and the unequal width dislocation of the end teeth on each side is proposed. Finally, the effectiveness of the proposed strategy is verified by FEM.