Deviation Analysis of Impulse Grounding Resistance Based on Impulse Coefficient

Abstract

Based on the impulse coefficient stipulated by the current national standards, this paper calculates the influence of impulse current amplitude, grounding device geometric size and soil resistivity on impulse ground resistance through simulation, and analyzes the reasons, and draws the following conclusions: the larger impulse current amplitude, the closer the impact coefficient is to the standard value; as the size of the grounding grid changes, the impact grounding resistance changes significantly, the larger the grounding grid, the longer the ray length and the smaller the impact resistance; as the soil resistivity increases, the same grounding grid under other conditions unchanged, the impact grounding resistance value will increase significantly, but the impact coefficient will decrease. When reducing the grounding resistance under the condition of high soil resistivity, we cannot blindly increase the size of the grounding body. Although the power frequency grounding resistance can be effectively reduced, the impact coefficient cannot be reduced to the standard requirements. The research has important guiding significance for the design of grounding devices for poles and towers in high soil resistivity areas.