Impulse Characteristics Of Grounding Electrode Under Lightning Current

The power system and buildings'lightning protection are very important, and the performance of the grounding system directly impact the effect of lightning protection'the study of the lighting impulse characteristics of grounding electrode has the very vital significance for better anti-thunder. This article uses ATP-EMTP and the FDTD simulation method to analyze the lighting impulse characteristics of grounding electrode under impulse current.In the first chapter, first of all, the basic concept and significance about grounding and impulse grounding are given, then this chapter analyses developing status of research impulse grounding and educes significance of this research from existent problem at present.The fundamental principium and research methods of impulse grounding system is analyzed detailed, and have carried on the introduction to the topic simulation tool.The impulse models of horizontal earth-termination electrode and vertical earth-termination electrode are established by using ATP-EMTP simulation method. The impact of length of the grounding electrode,soil receptivity and soil stratification to the grounding resistance are analyzed,and the phases'relationship of transient grounding resistance,impulse current and the incremental of electrode's voltage are studied,and analyzed the relationship between the maximum resistance from simulation and the resistance calculated by traditional method.Vertical earth-termination electrode and horizontal earth-termination electrode are studied using the FDTD simulation method. The distribution law of grounding electrode current density and electric field intensity is obtained. Then the article compared them with the conclusions which made by ATP-EMTP.In the end, by analyzing experimental results of ATP-EMTP and FDTD, some conclusions of lighting impulse characteristics of grounding electrode under lightning current are made.