一二次融合环网柜内置EVT的内锥套管局部放电分析  

Partial Discharge Analysis on Inner Cone Casing of Built-in EVT in Primary and Secondary Fusion Ring Cabinet

作　　者：李燕燕 郑晓果 LI Yanyan;ZHENG Xiaoguo(XJ Electric Co.,Ltd.,Xuchang 461000,China)

机构地区：[1]许继电气股份有限公司,河南许昌461000

出　　处：《电器与能效管理技术》2024年第10期31-35,共5页Electrical & Energy Management Technology

基　　金：国家电网有限公司科技项目(521997220031)。

摘　　要：为解决一二次融合环网柜内置电子式电压互感器(EVT)的内锥套管存在的局部放电问题,首先对其进行静电场分析,提取电场较为集中区域的电场分布;然后依据高电压电极均压技术及气-固复合绝缘理论,对EVT中心铜棒的结构和EVT端面形状及其与套管高压端面的配合间隙进行优化。优化后内置EVT的内锥套管三交界沿面最大场强由2.85 kV/mm降至1.75 kV/mm,套管端面最大场强由3.90 kV/mm降至2.35 kV/mm,理论上验证了所提方法的可行性。局部放电试验表明,优化后局部放电量由42.54 pC降为1.05 pC,证明了所提方法的实际可行性,为后续10 kV及更高电压等级的一二次融合相关组合绝缘结构的研发提供了有利指导。In order to solve the partial discharge problem of the EVT inner cone casing in the primary and secondary fusion ring cabinet,the electrostatic field analysis is carried out first to extract the electric field distribution in the area with relatively concentrated electric field.Then according to the high voltage electrode voltage sharing technology and the gas-solid composite insulation theory,the structure of the EVT center copper rod,the shape of the EVT end and the matching clearance with the high pressure end face of the casing are optimized.After optimization,the maximum field strength along the three interfaces of the EVT inner cone casing is reduced from 2.85 kV/mm to 1.75 kV/mm,and the maximum field strength at the end of the casing is reduced from 3.90 kV/mm to 2.35 kV/mm.The feasibility of the method is verified theoretically.The partial discharge test shows that the local discharge quantity is reduced from 42.54 pC to 1.05 pC after optimization,which proves the practical feasibility of the method,and provides a favorable guidance for the research and development of the composite insulation structure related to the quasi-primary and secondary fusion of 10 kV and higher voltage levels.

关 键 词：电子式电压互感器 内锥套管 局部放电 电场分析 绝缘结构 

分 类 号：TM64[电气工程—电力系统及自动化]