Abstract：High soil resistance rate in the substation could result in high grounding resistivity. Conventional method to solve this problem such as enlarging the grounding grid area is hard to implement due to the high land acquisition cost. Hence, three methods to decrease the soil resistivity without redundant land are proposed. Double-layer ground grid method is used when the deeper soil obtains low soil resistivity; ion earthing electrode method is used for the region which has rather high soil resistivity; inclined electrode methodis suitable for the area with uniformly distributed soil and intermediate soil resistivity. These methods have been analyzed and proved to be effective in engineering practice.
2018, Vol. 19 
