摘要
绝缘子表面电荷积聚是导致其发生沿面闪络的一个重要原因,影响着电力系统的安全运行。为了研究交流电压下气体绝缘输电管道(gas-insulated transmission line,GIL)中支柱绝缘子表面电荷积聚特性,基于有源静电探头法,搭建了针对简化处理后的支柱绝缘子表面电位测量平台,利用COMSOL仿真和静电场数值计算的方法求取了其传递函数矩阵,实现了由测量电位到表面电荷的反演计算,并对反演算法的准确性进行了验证。同时结合交流电压截断相位的提取方法,获得了交流电场下绝缘子表面电荷的分布特点和电压相位之间的关系。结果显示:圆台绝缘子表面正极性和负极性电荷同时存在,在高压电极附近有一个电荷相对集中且密度较高的“电荷带”;在布置金属丝的情况下,表面金属丝两端会出现一个异极性电荷组成的“电荷对”。无论是“电荷带”还是“电荷对”的极性,都和电压截断时刻的相位有关,电荷密度同时受电压幅值和截断相位的影响。
Charge accumulation on the insulator surface is one of the main factors that lead to insulator flashover,which affects the stable operation of power systems.In order to study the characteristics of surface charge accumulation on spacer in gas-insulated transmission line(GIL)under AC voltage,we set up a surface potential measurement platform of the simplified post insulator based on the active electrostatic probe method.By the means of COMSOL simulation and static electric field calculation,the transfer function matrix of the truncated cone-type insulator was achieved,and the charge distribution was obtained by inverse calculation.The accuracy of the inversion algorithm was verified by comparing the preset charges and the result of calculation.At the same time,the relationship between voltage phase and charge distribution on the insulator surface was obtained by extracting the truncated phase of AC voltage.The results show that positive and negative charges co-exist on the insulator surface,and there is a denser’charge band’near the high-voltage electrode.When a wire is arranged on the insulator surface,a hetero-polar’charge pairs’appear at the ends of the wire.Both the polarity of’charge band’and’charge pairs’are related to the truncated phase of AC voltage,and the charge density is affected by the voltage amplitude and the truncated phase.
作者
李大雨
张贵新
王天宇
LI Dayu;ZHANG Guixin;WANG Tianyu(Department of Electrical Engineering,Tsinghua University,Beijing 100084,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2022年第4期1480-1488,共9页
High Voltage Engineering
基金
国家重点研发计划(2017YFB0902500)
国家电网公司科技项目(环保型管道输电关键技术)(2017YFB0902500)。
关键词
交流电压
圆台绝缘子
截断相位
电荷带
电荷对
AC voltage
truncated cone-type insulator
truncated phase
charge band
charge pairs
