高压电缆绕组直线电机定子及绕组的涡流分析

为研究高压电缆绕组直线电机运行中可能出现的发热现象,建立了直线电机定子及绕组电缆的计算模型,用有限元法计算了电机在三相交流电作用下的涡流及电磁损耗分布,研究了绕组电缆有无金属屏蔽时电机内涡流分布的变化,并分析了涡流产生的热效应及其对电机运行带来的影响。研究表明,若定子绕组电缆有铜屏蔽层,运行时屏蔽层内将感应很大的涡流,其热效应可使电缆绕组烧损,进而严重影响高压电机的正常运行。研究结果可供高压直线电机定子绕组电缆的结构设计及选型参考。

Analysis of Eddy Current in Stator and Winding of High Voltage Linear Motor

In order to analyze the heat phenomenon of high voltage linear motor in operation,the computation model of its stator and winding cable was built firstly.The eddy current and electromagnetic loss distribution in high voltage linear motor were studied under three-phase alternating current by the finite-element method.When the winding cable had metal-shielded layer or no shielded layer,the eddy current distribution in linear motor was analyzed individually.Then the heat effect caused by eddy current was studied.The study made it clear that when the high voltage winding cable had metal-shielded layer,rather large eddy current would be induced in this shielded layer and the heat caused by eddy current may burn out the winding cable,which badly influenced the normal working of high voltage motor.At the same time,the eddy current in winding cable rapidly increased with the increase of power frequency.The eddy current was not uniformly distributed in the metal-shielded layer,and the winding cable located in stator slot where the eddy current had the maximum value would be firstly burn out.The computation results provide some useful references for the design and selection of stator winding cable in high voltage linear motor.