山地地形对±1100 kV输电线路雷电屏蔽性能影响模型试验  

Model Test of the Effect of Mountain Terrain on Lightning Shielding Performance of±1100 kV Transmission Lines

作　　者：赵江涛 戴敏 陈伟 张韬[3] 邓冶强 王羽[3] ZHAO Jiangtao;DAI Min;CHEN Wei;ZHANG Tao;DENG Yeqiang;WANG Yu(State Grid Corporation of China,Beijing 100031,China;China Electric Power Research Institute,Wuhan 430074,China;School of Electrical Engineering and Automation,Wuhan University,Wuhan 430072,China)

机构地区：[1]国家电网有限公司,北京100031 [2]中国电力科学研究院有限公司,武汉430074 [3]武汉大学电气与自动化学院,武汉430072

出　　处：《高电压技术》2020年第9期3318-3324,共7页High Voltage Engineering

基　　金：国家重点研发计划(2016YFB0900800);国家电网公司科技项目(GY71-17-041)。

摘　　要：雷害是输电线路故障的主要原因之一,为研究平原与山地情况下±1100k V输电线路雷电屏蔽性能的差异性,开展了以±1100 kV特高压直流输电线路Z38102AL型铁塔为对象,模型比例为1:12.5且山地情况下雷电屏蔽模拟试验,采用负极性250/2500μs操作冲击电压波对模型线路进行放电并开展观测,统计分析了山地地形下放电路径、绕击概率与放电参数,并与平地地形试验及±800kV线路试验结果进行对比。研究结果表明:山地地形的地电位空间变化改变了空间电场,坡地对下行先导的吸引作用使得山区输电线路更易遭受绕击;±1100kV输电线路绕击概率的空间分布近似为抛物线;山地地面屏蔽效果较弱,与平地试验相比总绕击概率更大且放电分散性增加,在山坡影响下,暴露空间的增大与空间电场变化对绕击概率的影响要强于导线电压的极性效应,使得山地地形下正负极性导线绕击概率差异较小;与±800 kV试验结果相比,±1100 kV正负极性导线绕击概率差异更大,其正极性导线对负极性雷的吸引能力有更明显的提升作用。研究结果对不同地形条件下特高压输电线路的雷电防护设计具有一定的参考价值。Lightning damage is one of the main causes of transmission lines faults.In order to study the difference in lightning shielding performance of±1100 kV transmission lines in plain and mountainous areas,a Z38102 AL tower with the ratio of 1:12.5 of±1100 kV UHV transmission lines was used to carry out the lightning shielding simulation tests in mountainous areas.The negative switching impulse voltage with a waveform parameter of 250/2500μs was adopted,and the discharge path,discharge voltage,and discharge time under mountainous terrain were statistically analyzed.Moreover,the results with ground terrain test and±800 k V line test were compared.The results show that the spatial variation of ground potential in mountainous terrain changes the space electric field,and the attraction of the slope to the downward leader makes the transmission line in the mountain area more vulnerable to lightning.The spatial distribution of shielding failure probability of±1100 kV transmission line is approximately parabola,and the shielding effect of the mountainous terrain is weak compared with that of the flat test.The total shielding failure probability is higher and distribution of discharge is larger in mountainous area.It is concluded that,under the influence of mountain slopes,the increase of exposure space and the change of space electric field have a stronger effect on the shielding failure probability than the polarity effect of conductor voltage,which makes the difference of conductor polarity in mountainous terrain smaller.By comparing the results from±800 kV tests,it is found that the shielding failure probability difference between positive and negative conductor of±1100 kV line is more remarkable,and its positive conductor will enhance the attraction of negative polarity lightning more obviously.The results are valuable for the design of lighting protection of UHV transmission lines under different terrain conditions.

关 键 词：雷电屏蔽 特高压 山地地形 绕击 放电路径 放电参数 

分 类 号：TM863[电气工程—高电压与绝缘技术]