特高压气体绝缘开关设备的隔离开关残余电荷电压仿真分析

Simulation Analysis of Potential Caused by Trapped Charge in Disconnector of UHV Gas Insulated Switchgear Device

为研究特高压气体绝缘开关设备的隔离开关残余电荷电压特性及其仿真方法,首先分析了残余电荷电压的几种影响因素;并在真型试验平台上开展了大量试验研究,对气体绝缘开关设备隔离开关分闸空载短母线所产生的触头间隙重复击穿过程进行了分析。基于试验结果,采用一元线性回归法得到触头间隙的击穿特性表达式,并在此基础上得到了残余电荷电压统计特性的仿真方法。结果表明,触头间隙正、负极性击穿电压之比约为1.3：1;正极性击穿电场强度在22~26 k V/mm之间。减小隔离开关开断速度,增大正、负极性击穿电压之差,降低SF6绝缘耐受强度都可以降低高幅值残余电荷电压的出现概率。

In order to understand the potential caused by trapped charge in ultra-high-voltage gas insulated switchgear（referred to as residual voltage） and its simulation method, we discussed the main factors influencing residual voltage. On the baisi of a large number of experiments on a full-scaletest platform, we analyzed the repetitive breakdown process between the contacts induced by disconnecting no-load short bus with gas insulated switchgear. Using the results, we deduced characteristic equations of the breakdown by the one-dimensional linear regression method, and then obtained a simulation method for obtaining the statistical properties of residual voltage. It is obtained that, for the gap between contacts, the ratio of positive breakdown voltage to negative one is about 1.3：1, and the positive breakdown electric field intensity varies from 22 k V/mm to 26 k V/mm. Furthermore, decelerating the switch-on/off of disconnector, increasing the difference between the positive and negative breakdown voltages, and reducing the SF6 insulation withstand voltage can all reduce the occurrence probability of high-amplitude residual voltages.