模型比例对架空输电线路雷电屏蔽模拟试验的影响  

Effects of Model Scale on Lightning Shielding Simulation Test of Overhead Transmission Lines

作　　者：王羽[1] 文习山[1] 蓝磊[1] 安韵竹[1] 鲁海亮[1] 杨跃光[1] 

机构地区：[1]武汉大学电气工程学院,武汉430072

出　　处：《高电压技术》2013年第2期443-449,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724500)~~

摘　　要：为了研究模型比例对输电线路雷电屏蔽模拟试验的影响,采用操作冲击电压,分别对按1:80、1:40和1:25比例缩小的平原500kV典型线路模型进行了放电试验。根据试验数据,绘制出了空间落雷点的绕击率分布图,并采用面积法计算了3种情况下的绕击率,分别与采用规程法、电气几何模型(electrogeometric model,EGM)法、改进EGM法的计算结果进行了对比。结果表明:空间落雷点绕击的概率分布图与采用EGM法计算得到的绕击空间分布规律基本一致;采用高速摄影可以观测到当主放电击中避雷线(导线)时,避雷线(导线)上竞争失利的残余迎面流注。采用操作冲击电压进行了雷电屏蔽模拟试验,所得到的各比例模型下线路的总绕击率相差甚远,放电分散性明显;模型尺寸对试验结果的影响较大。In order to study the effects of model scale on lightning shielding performance of transmission lines in simulative experiments,we performed a series of discharge tests on typical scaled models of 500 kV transmission lines in plain terrain,in which switching impulses were adopted.The model scales were 1：80,1：40,and 1：25 to actual transmission lines.Based on the test results,the spatial distribution of shielding failure probability with switching impulse voltage was plotted,and the shielding failure probability was calculated by using the area method.Furthermore,the calculation results were compared with the results calculated with other methods,such as the method in the electric power industry guide,the electrogeometric model（EGM） method,and the improved EGM method.The comparison indicated that the distribution rule of the obtained shielding failure probability plot basically agreed with the calculation results from EGM model.Moreover,we observed the residue upward streamer incepted from the surface of conductors which was fail to hit and the primary discharge by using a high-speed camera.Lightning shielding simulative tests using switching impulses were also carried out on the 3 models,and the shielding failure probabilities of each model were quite different from each other,meanwhile the discharge haphazard was obvious.In general,the size of model had significant influence on the tests results.

关 键 词：模型比例 雷电屏蔽 模拟试验 绕击率 电气几何模型(EGM) 改进EGM 

分 类 号：TM863[电气工程—高电压与绝缘技术]