摘要
变电站接地网的安全性问题已成为电力系统电磁兼容的重要研究课题之一。文中基于有限元方法,将接地网一维导体单元与三维土壤单元相耦合,并考虑导体阻抗的频变特性,研究变电站接地网的接地性能。与三维有限元的A-V方法相比,该文计算方法的计算量大大降低,同时可以考虑频率对接地网接地性能的影响。通过与矩量法和测量结果进行比较,验证了该计算方法的正确性和有效性。利用计算得到的接地网导体轴向电流和土壤泄漏分布电流,进一步计算了接地网产生的空间磁场强度。结果表明,文中方法与矩量法的计算结果略有差异,原因在于矩量法中未考虑土壤泄漏分布电流的影响,文中计算方法可以方便地应用于复合土壤结构的接地网的接地性能分析。
Safety analysis of the substation grounding grids is one of important subjects on electromagnetic compatibility （EMC） in power system. Based on finite element method （FEM） of 1D conductor element coupled with 3D soil element, we consider the frequency dependent characteristic of the conductor impedance to analyze the grounding performance of the substation grounding grids. Compared with A-V formulation of 3D FEM, the proposed method can save the CPU time considerably and take frequency into account during FEM modeling. Compared with method of moment （MoM） and the measured results, the presented method is proved to be correct and effective. Furthermore, we can calculate the H-field generated by the substation grounding grids with both currents in underground conductors and leakage currents flowing in the soil. The results show slight difference between FEM and MoM, which can be explained by the fact that the leakage currents in the soil are not considered for MoM. The proposed method can be conveniently applied for the grounding performance analysis of the grounding grids in complex soil. su
出处
《中国电机工程学报》
EI
CSCD
北大核心
2007年第6期62-66,共5页
Proceedings of the CSEE
基金
国家杰出青年科学基金项目(50325723)~~
关键词
变电站接地网
复合土壤
有限元方法
频变特性
bstation grounding grids
complex soil finite element method
frequency dependent characteristic
