真空灭弧室击穿分析及仿真优化

Analysis of breakdown and simulation optimization for vacuum interrupter

真空灭弧室作为真空断路器的开断单元,制约着真空断路器的绝缘和开断性能。为提升真空灭弧室绝缘性能,本文分析真空灭弧室与地电位平板在不同相对位置、动静端分别加压条件下的电场分布情况,探究真空灭弧室瓷套绝缘击穿的根本原因,进而创新性地优化真空灭弧室内均压罩的固定方案,消除楔形气隙。改进后真空灭弧室击穿点瓷套内部的电场强度降至0.02kV/mm,较改进前降低了99%,避免了均压罩固定点高电场强度引起的绝缘击穿,为真空灭弧室的结构优化提供了解决思路。

The vacuum interrupter,as the breaking unit of the vacuum circuit breaker,restricts the insulation and breaking performance of the vacuum circuit breaker.In order to improve the insulation performance of the vacuum interrupter,this article analyzes the electric field distribution of the vacuum interrupter and the ground potential plate at different relative positions and under different pressures at the dynamic and static ends.It explores the fundamental reasons for the insulation breakdown of the magnetic shell of the vacuum interrupter,and innovatively optimizes the fixing scheme of the voltage equalization cover in the vacuum interrupter,eliminating the wedgy airgap.After improvement,the electric intensity inside the porcelain sleeve at the breakdown point of the vacuum interrupter is reduced to 0.02kV/mm,which is 99%lower than that before improvement,avoiding insulation breakdown caused by high electric intensity at the fixed point of the voltage equalization cover.This provides a solution for the structural optimization of the vacuum interrupter.