影响高压断路器用均压油纸电容器绝缘性能的因素

随着电压等级的不断提高,高压断路器串联的断口数相应增多,各断口的电压不均匀程度增大。为均匀各断口间的电压分布,通常在断口间并联均压电容器。油纸电容器以其重量轻,可靠性高等优点越来越多地应用到高压断路器中。文中采用有限元分析方法,分析了影响均压电容器表面电场强度分布的几个因素,包括均压电容器与屏蔽罩间的距离、屏蔽均压电容器端部的两屏蔽罩间距离及均压电容器两侧深入屏蔽罩的均匀度。并得出如下结论:在满足屏蔽罩对地绝缘的条件下,均压电容器与屏蔽罩间的距离越大越好;在既满足主断口绝缘性能又满足电容器绝缘性能的前提下,屏蔽均压电容器端部的两屏蔽罩间距离越大越好;在保证断口绝缘性能的前提下,均压电容器两侧深入屏蔽罩的距离越均匀越好。研究结果为新产品结构设计及工程设计提供了一定的理论指导和依据。

Factors Affecting the Insulation Property of Voltage-equalizing Oil-paper Capacitor for High Voltage Circuit Breaker

As the voltage increasing,the number of chambers for high voltage circuit breaker is increasing,the uniformity of every chamber is decreased.To uniform the voltage,the voltage-sharing capacitor is always used.The oilpaper capacitor is widely used for its lower weight and higher reliability.This paper adopts FEM method to analyze the factors of insulation property for voltage-sharing capacitor,including the following:the distance between voltagesharing capacitor and shielding,the distance for the shielding of voltage-sharing capacitor,the uniformity of the shielding distance for the voltage-sharing capacitor.The result is:when the insulation of shielding is satisfaction,the distance between voltage-sharing capacitor and shielding is the longer the better;when the insulations of the circuit breaker and the capacitor are all satisfaction,the distance for the shielding of voltage-sharing capacitor is the longer the better;when the insulation of the circuit breaker is satisfaction,the shielding distances of the capacitor are the more uniform the better.The research results provide theoretical guidance and basis for the new product structure design and project design.