变电站多层次复合接地的土壤高效降阻技术OA

This paper addresses grounding resistance reduction for substations located in areas with ultra-high soil resistivity,typical in hydropower plants.It systematically analyzes the technical challenges associated with grounding resistance reduction in substations where the soil resistivity is approximately 2 700 Ω·m.It proposes a soil-adapted high-efficiency resistance reduction technology,namely a multi-layer composite grounding system employing"deep wells+equipotential belts+ion electrodes+new resistance-reducing materials".According to theoretical calculation,the power frequency grounding resistance of the entire grounding grid of the substation can be reduced to 0.42 Ω,which is lower than the design requirement of 0.5 Ω for the grounding resistance of the grounding grid in hydropower plant substations.In practical application,the power frequency grounding resistance of the entire grounding grid of the substation is only 0.38 Ω,better than the expected effect of theoretical calculation.This proves that this resistance reduction technology has excellent application effect,which is sufficient to achieve high-standard resistance reduction targets and solve the problems encountered in the construction of high-standard grounding grids in high-resistivity soil environments.