地磁暴感应地电场的大地电性结构建模方法  

Earth Conductivity Modelling Technique for Calculating Geoelectric Field during Geomagnetic Storms

作　　者：王泽忠[1] 董博[1] 刘春明[2] 刘连光[2] 林晨翔 

机构地区：[1]华北电力大学高电压与电磁兼容北京市重点实验室,北京102206 [2]华北电力大学电气与电子工程学院,北京102206

出　　处：《科学技术与工程》2015年第13期72-76,共5页Science Technology and Engineering

摘　　要：探明磁暴期间地面感应电场的分布情形是正确计算地磁感应电流(GIC)和预测磁暴次生灾害影响的前提。根据电磁场唯一性定理,从求解磁暴感应地电场的角度出发,提出了一种复杂大地电导率结构的建模方法;该方法的特点是只建大地导体区模型,通过模型的边界条件反映地磁场的变化情况及感应地电流在地下的流通情形。采用有限元法求解了典型地电结构下的磁暴感应地电场,通过对比数值方法和解析方法求得的地面电场结果,验证了建模方法的可靠性。进一步采用该方法研究了无法解析求解的复杂地电结构的磁暴感应地电场问题,建模思路和方法为评估磁暴和GIC的管网效应提供了分析工具。Investigated the distribution of geoelectric field is the primary factor to evaluate the impact of geomag- netically indueed currents （GIC） during geomagnetic storms. Based on the uniqueness theorem in electromagnetic theory, a technique to model the Earth structure with complicated conductivity values is presented. The main fea- ture of this technique is that only the conductive Earth is needed to be modelled. The electromagnetic field and the induced currents in the Earth can be obtained by solving the governing equations under the suitable boundary condi- tions. After modelling one basle conductivity structure, results from the Finite Element Method （FEM） are com- pared with those from analytical method to test the reliability of the modelling technique. Furthermore, one compli- cated conductivity structure where the analytieal method cannot be applied is modelled and the electromagnetic fields are calculated. The presented technique can be seen as an effective tool to assess the GIC effect in power systems.

关 键 词：磁暴 地电场 地磁感应电流(GIC) 大地电性结构 有限元法 

分 类 号：TM715[电气工程—电力系统及自动化]