220kV线路悬式绝缘子串异物临近放电机制研究  

Study on Discharge Mechanism of Suspension Insulator String of 220 kV AC Transmission Line with External Object Approaching

作　　者：黄道春[1] 余俊[1] 张宇[2] 张化昭 夏景欣[1] 况燕军 阮江军[1] 陈智[2] 

机构地区：[1]武汉大学电气工程学院,湖北省武汉市430072 [2]国网江西省电力科学研究院,江西省南昌市330000

出　　处：《中国电机工程学报》2014年第24期4161-4170,共10页Proceedings of the CSEE

基　　金：国网江西省电力公司科技项目(201150601);江西省科技计划项目(2011ZBBH80020)~~

摘　　要：为研究玻璃绝缘子串在鸟粪和鸟巢材料(异物)下落时的放电机制,用铁丝模拟异物进行了试验研究,首先开展了异物临近时间隙放电试验,基于对不同铁丝长度和空间布置时放电电压的测量和放电路径的观察,分析了放电机制。研究表明:当足够长的铁丝临近绝缘子串时,放电过程仅是铁丝上下两端空气间隙的击穿过程;当较短的铁丝临近时,放电过程为空气间隙击穿和绝缘子沿面放电的混合。然后开展了铁丝与金具电极间隙放电试验,基于对不同间隙长度下放电电压的测量,分析了间隙放电特性,研究表明铁丝–金具间隙与典型的棒–棒间隙击穿特性相似,理论计算中取平均击穿电压梯度为4.0 kV/cm。最后建立了实际线路和试验布置的三维有限元模型,研究异物临近对绝缘子串周围电位和电场分布的影响,将仿真计算得到的放电电压与实际试验电压进行对比,验证了试验结果的准确性。放电机制、试验和仿真结果可为输电线路杆塔涉鸟故障风险区域划定提供参考依据。To study the discharge mechanism when bird streamer or nest material（external object） drop near the glass insulator string, using iron wires to simulate bird streamer and nest material, experiments were carried out to investigate the discharge voltage and path of discharge when the length and horizontal distance of the iron wires vary. The results show that the discharge process of external object approaching insulator string can be divided into two catergries： when the long iron wire approaches the insulator string, it is air breakdown only; when the short iron wire approaches the insulator string, it is combination of surface discharge and air breakdown. Discharge experiments on the air gap between iron wire and fitting were carried out at the same time, the results show that the gap between iron wire and fitting can be regarded as typical rod-rod gap, and average breakdown voltage can be used in the simulation analysis. Simulation model is set up by using finite element method （FEM） to study the influence of the position of external object on electric field distribution; the theoretical discharge voltage obtained from simulation were compared with the results of experiments, the accuracy of the experimental results was validated. Discharge mechanism, experimental and simulation data can be a reference for the bird damage risk area determination of transmission line tower.

关 键 词：输电线路 悬式绝缘子串 放电机制 异物 鸟粪 鸟巢材料 有限元法 

分 类 号：TM852[电气工程—高电压与绝缘技术]