Measurement and simulation of grounding resistance with two and four mesh grids

This paper presents the simulation and measurement of grounding resistance with two different mesh grids. Initially, soil resistances have been measured by F. Wenner four-pole equal method at the selected sites near the Power Station. Then soil resistivity has been calculated from the measured soil resistance. The root mean square errors between the measured and simulation soil resistivities are respectively found to be 3.77% and 4% for two and four mesh grids. The Fall-of-potential (FOP) method is used to measure the grounding resistance and the minimum values are found to be 100.3Ω and 96.8Ω respectively for two and four mesh grids. The measured results are then compared with the simulation results and are found to be in good agreement. In addition, ground potential rise (GPR), maximum permissible step and touch potentials have been calculated using CYME GRD simulation software.