Design and Modelling of Earthing System for EHV Substation on Non-Uniform Soil Using MiPower

In this paper, an earthing system is proposed for extra high voltage (EHV) substation on non-uniform soil. The main objective of the proposed model is to develop a secure earthing system that prioritizes safe and reliable operation, even when soil conditions are uncertain. This involves analyzing the non-uniform soil of the substation site using two-layer soil model to determine the soil resistivity. The resistivity data is then used to model and simulate the earthing system using MiPower software. The results of the simulations are analysed, and recommendations are made for the optimal earthing design.