The new three-dimensional structure of long grounding rod for large-scale substation

Abstract

Slanting Grounding Rod is a new three-dimensional structure of long grounding rod. In the paper it has been in-depth analysis from both effect of resistance reduction and design programs. Different from conventional Vertical Grounding Rod, there is an angle between grounding rod and ground's vertical direction. Therefore effectively solve the problem that both effect and cost of resistance reduction are not satisfied when conventional Vertical Grounding Rod is used in the soil of deep soil resistivity higher than surface soil resistivity. By numerical simulation, consider uniform soil, effect of resistance reduction of Slanting Grounding Rod is about 1.3 times as that of the same length Vertical Grounding Rod. Consider the double-layer soil of deep soil resistivity higher than surface soil resistivity, effect of resistance reduction of Slanting Grounding Rod is about 2 to 8 times as that of the same 60 m Vertical Grounding Rod. For large grounding grid, the time is higher. Installing Slanting Grounding Rod in the double-layer soil, the optimal angle design principle is that parts of Slanting Grounding Rod buried in the low resistance soil are as much as possible.