基于矢量匹配法的复杂土壤环境下接地棒雷击暂态电路模型研究  

Lightning Transient Circuit Model of the Grounding Electrode Under Complex Soil Environment Based on Vector Fitting Method

作　　者：周玉娟[1] ZHOU Yujuan(Jiangsu Open University,Nanjing 210036,China)

机构地区：[1]江苏开放大学建筑工程学院,南京210036

出　　处：《电瓷避雷器》2022年第5期119-124,共6页Insulators and Surge Arresters

基　　金：江苏省高校自然科学研究重大项目(编号:18KJA470002);江苏省高校哲学社会科学研究项目(编号:2020SJA0778)。

摘　　要：复杂土壤环境下接地棒泄散雷电流环境复杂,需要建立合适接地棒暂态电路模型以进行有效仿真分析。本研究通过矢量匹配法结合最小二乘法求取海陆混合环境下接地棒暂态电路模型,利用EMTP软件计算接地棒雷击暂态电位抬升,最后分析土壤环境参数对暂态电位抬升的影响,讨论海洋环境对接地棒电路模型的临界影响距离。研究结果表明:上层土壤电阻率高于下层土壤电阻率环境中,接地棒雷击暂态电位抬升随着距海洋距离的增大而升高,但上层土壤电阻率高低于下层土壤电阻率时变化趋势恰恰相反;当接地棒距海洋环境距离超过15 m时,暂态电位抬升变化不明显,且15 m临界距离受雷电流波头时间影响不大;随着上层土壤厚度的增加,接地棒暂态电位抬升受上层土壤影响也不断增大。复杂土壤环境中当接地棒距海洋环境距离小于15 m时,必须予以考虑海洋对接地棒暂态电路模型的影响。The grounding electrode is faced with complex process when lightning current flows under complex soil environment such as ocean-land mixed environment, it is necessary to establish transient circuit of the grounding electrode for proper analysis. Exact transient circuit model of the grounding electrode in the presence of oceans was extracted by means of vector fitting method(VFM) in combining with leastsquare technique. Groundingpotential riseof the grounding electrode was calculated. Effect of soil parameters was analyzed and critical spacing was from the ocean-land interface discussed. Results show that: when the first layer soil resistivity is higher than the under layer, the ocean effect results in an increase of grounding potential rise of the grounding electrode, whereas for the lower first layer soil resistivitythe grounding potential rise is decreased. When the spacingfrom the ocean-land interface exceeds 15 m, the grounding potential rise shows no obvious change and this distance islittle affected by lightning current wave front time. With the increase of thickness of the first layer, its influence on grounding potential rise becomes more and more remarkable. When the spacing from the ocean-land interface is less than 15 m, the ocean-land mixed propagation path cannotbe disregarded.

关 键 词：复杂土壤环境 海陆混合 雷电 接地棒 暂态电路模型 矢量匹配法 

分 类 号：TM862[电气工程—高电压与绝缘技术]