多层水平土壤地表电位分布的仿真分析  

Simulation and Analysis of Earth Surface Potential Distribution in Horizontal Multi-layer Soil

作　　者：潘卓洪[1] 张露[1] 刘虎 鲁海亮[1] 文习山[1] 

机构地区：[1]武汉大学电气工程学院,武汉430072 [2]湖北超高压输变电公司,宜昌443000

出　　处：《高电压技术》2012年第1期116-123,共8页High Voltage Engineering

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

摘　　要：直流输电入地电流可能在交流系统内分布,对变压器和电网安全运行造成一系列不良影响。地表电位(ESP)分布是直流分布的重要参数,为提高数值计算的精度,基于矩阵束方法提出了一种求解格林函数的高阶复镜像法。算例证明了接地标准软件CDEGS在求解奇异格林函数时存在缺陷,高阶复镜像法克服了过往方法的不足,可以精确求解任意参数多层水平土壤的格林函数,且更高的复镜像阶数虽然可以减少拟合误差,但对格林函数计算结果的偏差无明显影响。最后对比了双环直流接地极和点电流源关于ESP的差异,如果直流极离开变电站大于10倍直流极尺寸,则可以用点电流源代替具体的直流极来计算ESP。DC distribution in AC grid caused by earthing current of HVDC transmission impairs transformer and AC grid.Earth surface potential（ESP） is an important parameter of DC distribution.To improve accuracy of numerical method,we put forward a high-order complex image method to obtain Green＇s function solution based on matrix pencil method.Numerical examples showed that software CDEGS was defective when applied to singular Green＇s function.High-order complex image method was used to overcome this defect.Moreover,Green＇s function arbitrary parameter horizontal soil could be obtained by this method.Higher order could reduce approximation error but deviation of computational result was not significantly affected.Meanwhile,ESP of the double-cirque DC grounding electrode and the point current source was compared.If the distance of DC grounding electrode and substation is 10 times size of electrode,DC grounding electrode can be approximated to a point current.

关 键 词：多层水平土壤 地表电位(ESP) 格林函数 高压直流输电 高阶复镜象法 直流接地极 

分 类 号：TM862[电气工程—高电压与绝缘技术]