土壤电离动态过程对接地装置冲击散流的影响分析  

Effect Analysis About Impulse-current Dispersal Regularity of Grounding Device Under Transient Ionization Phenomenon of Soil

作　　者：袁涛[1] 李景丽[1] 司马文霞[1] 杨庆[1] 孟宪丰[2] 田川[2] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]四川达州电业局,达州635000

出　　处：《高电压技术》2011年第7期1606-1613,共8页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724504)~~

摘　　要：准确地分析接地装置的冲击散流规律是接地优化设计和提高输电线路防雷性能的基础。为考虑雷电流经过接地装置散流时,由于土壤电离动态过程的存在,接地装置周围土壤在散流过程中呈现的非线性特性,及其对接地装置冲击散流规律的影响,通过模拟试验和仿真计算对这一过程及其影响进行了研究。提出了考虑土壤电离动态过程非线性的计算模型,并基于模拟试验和数值计算分析了不同结构接地装置泄放冲击电流时的散流规律,结合火花放电理论探讨了接地导体之间的屏蔽作用和土壤电离的物理过程及其对接地装置冲击特性的影响。结果表明土壤动态电离现象在冲击散流过程的影响不可忽视。When impulse current dissipates into earth through the grounding system, the impulse dispersal process is characterized with nonlinear feature as the result of the dynamic ionization of soil, which finally has a great effect on the dispersal regularity. Based on the experiment and simulation, the effect of the soil dynamic ionization on dispersal process of grounding devices was studie＆ A nonlinear computation model considering the soil dynamic ionization was presented. Based on the measurement and simulation results, the dispersal regularities of various grounding electrodes were analyzed. Moreover, the shielding effect between grounding electrodes, as well as the effect of soil i- onization process on lightning transient dispersal regularity, was discussed based on the spark discharge theorem. The results show that. the effect on impulse current disoersal caused by soil ionization is unignorable.

关 键 词：接地 冲击散流 土壤电离 火花放电 电流分布 暂态电阻 

分 类 号：TM862.3[电气工程—高电压与绝缘技术]