1次触发闪电引起的地网地电位抬升观测及分析  

Observation and Analysis of Ground Grid Potential Rise by One Triggered Lightning Flash

作　　者：颜旭[1,2] 揣国权 王孝波[3] 李哲 杜赛 张义军 YAN Xu;CHUAI Guoquan;WANG Xiaobo;LI Zhe;DU Sai;ZHANG Yijun(Guangzhou Institute of Tropical and Marine Meteorology,CMA,Guangzhou 510080,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China;Guangzhou Meteorological Bureau,Guangzhou 511430,China;College of Electronic Engineering,Chengdu University of Information Technology,Chengdu 610225,China;Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences,Fudan University,Shanghai 200438,China)

机构地区：[1]中国气象局广州热带海洋气象研究所,广州510080 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081 [3]广州市气象局,广州511430 [4]成都信息工程大学电子工程学院,成都610225 [5]复旦大学大气与海洋科学系/大气科学研究院,上海200438

出　　处：《高电压技术》2020年第12期4120-4128,共9页High Voltage Engineering

基　　金：国家重点研发计划(2017YFC1501506);灾害天气国家重点实验室基金(2018LASW–B14)。

摘　　要：雷电流通过地网泄放时,会使地网上的电位显著升高,极具破坏性。因此,基于人工触发闪电技术,分析了触发闪电雷电流波形特征和对应的地电位抬升波形特征,并结合CST软件进行了仿真建模与观测数据进行对比分析。分析发现,4次回击过程引起的地电位抬升最大值可达-353.49 kV,平均值为-254.69 kV,电压波形半峰宽度明显大于对应过程的雷电流波形,约为后者的1.8倍;雷电流直击地网时,由于地网暂态效应作用,当回击电流较大时(-25.80 kA),冲击接地电阻偏小,其值约是工频接地电阻的86.5%;当回击电流较小时(-9.07 kA),冲击接地电阻偏大,其值约是工频接地电阻的1.4倍。通过Heidler函数和双指数函数可以较好地模拟雷电流波形,地电位抬升模拟结果显示,上升沿和峰值较为接近观测值,半峰宽度比实测值小,模型难以模拟自然过程的火花效应,是造成模拟与实测结果存在偏差的重要原因。The discharges of lightning current to ground through a grounding grid will result in significantly higher potential rise at the grounding grid, which is very destructive. Therefore, based on artificially triggered lightning technology, the characteristics of lightning current waveform and the corresponding ground potential rise(GPR) waveform at one triggered lightning flash was analyzed, moreover, a comparative analysis is conducted between simulation and observation in combination with the CST simulation software. The analyses reveal that the peak value of four return strokes with the GPR reaches-353.49 kV with an arithmetic mean value of-254.69 kV. The half-peak width of the GPR waveform is about 1.8 times the corresponding parameter of the current waveform. It can be also found that the impulse grounding resistance is about 86.5% of the low-frequency grounding resistance for larger currents such as-25.80 kA, and 1.4 times the low-frequency resistance for smaller currents such as-9.07 k A. The Heidler function and the double exponential function can be adopted to well simulate the lightning current waveform. The simulation results show that the peak value and the rise time of the simulated GPR waveform agree well with the observations, and the simulated half-peak width is smaller. The important reason of the inconsistency between the simulation results and the observations is that the model cannot simulate the soil ionization during the natural process.

关 键 词：人工触发闪电 回击电流 地网 地电位抬升 冲击接地电阻 

分 类 号：TM862[电气工程—高电压与绝缘技术]