电压暂降起始点与相位跳变对交流接触器影响的分析

摘要

电压暂降是电能质量中较为严重的问题之一，它对交流接触器等敏感设备造成了严重的影响。除电压暂降幅值和持续时间两个特征量会影响交流接触器的正常运行外，暂降的起始点、相位跳变等特征量也会对交流接触器的通断造成较大影响。文中进行了电压暂降对交流接触器影响的机理分析，建立了仿真模型，进行了暂降起始点、相位跳变对交流接触器磁通变化的影响分析与接触器通断分析；选取主流厂家生产的8个交流接触器进行了试验研究，得到了与机理分析相一致的结果，并绘制了电压暂降不同起始点与相位跳变特征量下交流接触器的耐受度曲线，可为交流接触器应对电压暂降问题提供基础数据，以减小电压暂降对其造成的影响，降低经济损失。%Voltage sag is one of the serious problems of power quality,which would cause severe impact on sensitive equipment such as alternating current (AC) contactors.In addition to voltage sag amplitude and duration which will affect the normal operation of AC contactors,the characteristics such as point-on-wave of sag initiation,sag phase jump also have significant impact on the switching of AC contactors.This paper makes a mechanism analysis of the impact of voltage sag on the AC contactor and builds a simulation model of the sag for analyzing the impact of point-on-wave of sag initiation and phase jump on the flux variation and switching of the AC contactor.Then eight AC contactors from mainstream manufacturers are studied and test results consistent with the results of the mechanism analysis are obtained.Finally,the AC contactor”s tolerance curves with different voltage sag characteristics of point-on-wave of sag initiation and the phase jump are plotted,which can provide basic data for the AC contactor to deal with the problem of voltage sag and reduce the corresponding economic loss.