Fractal model of lightning channel for simulating lightning strikes to transmission lines  

作　　者：HE JinLiang ZHANG XueWei DONG Lin ZENG Rong LIU ZeHong 

机构地区：[1]Department of Electrical Engineering,Tsinghua University,Beijing 100084,China [2]Department of UHV Construction,State Grid Corporation of China,Beijing 100031,China

出　　处：《Science China(Technological Sciences)》2009年第11期3135-3141,共7页中国科学（技术科学英文版）

基　　金：Supported by the National Nature Science Foundation of China (Grant No. 50737001);the National Basic Research Program of China ("973" Project) (Grant No. 2009CB724504)

摘　　要：How to accurately evaluate the direct-strike lightning protection is one of the key issues in the design of transmission lines. In this paper, three important issues in applying the fractal simulation to the lightning protection of transmission lines were discussed, including the criteria and implementation of upward leader inception, the connection with the magnitude of lightning current, and the calculation and control of fractal dimensions. Then we conducted the simulation iterately, leading to statistical results, which indicate that even if the transmission line satisfies the perfect shielding condition, shielding failure fault remains possible. Furthermore, we calculated the shielding failure fault rates of an EHV line with different ground obliquities and distribution of strike points over the interval between two neighboring towers along a UHV-DC line to find out the weak point of transmission-line lightning protection. This work provides a promising approach for improving the lightning protection property of transmission lines by optimizing the configuration of shielding wires and phase or pole conductors.How to accurately evaluate the direct-strike lightning protection is one of the key issues in the design of transmission lines. In this paper, three important issues in applying the fractal simulation to the lightning protection of transmission lines were discussed, including the criteria and implementation of upward leader inception, the connection with the magnitude of lightning current, and the calculation and control of fractal dimensions. Then we conducted the simulation iterately, leading to statistical results, which indicate that even if the transmission line satisfies the perfect shielding condition, shielding failure fault remains possible. Furthermore, we calculated the shielding failure fault rates of an EHV line with different ground obliquities and distribution of strike points over the interval between two neighboring towers along a UHV-DC line to find out the weak point of transmission-line lightning protection. This work provides a promising approach for improving the lightning protection property of transmission lines by optimizing the configuration of shielding wires and phase or pole conductors.

关 键 词：LIGHTNING SHIELDING failure transmission line FRACTAL theory dielectric BREAKDOWN MODEL electrogeometric MODEL 

分 类 号：TM862[电气工程—高电压与绝缘技术]