Comparison between Earthing System Designing Parameters for Different Types of Soil Resistivity Area and Minimization of Limitation

Shaktikant Patel, Anil Kumar Kori

Abstract: This paper presents the design of safe, reliable and effective earthing system designing for different types of soil resistivity area. Also present the calculation of parameters and comparison between their parameters. Know very well that substation soil resistivity is very important factor for earthing system designing. According to soil characteristics (soil resistivity, soil structure and soil model) designed the earthing system of AC substation. This paper mainly focuseson the soil resistivity. Earthing system provides the low resistance path for fault current therefore when designing earthing system it is advisible to locate the area with lowest soil resistivity in order to achieve the economical and effective earthing system. If any case low resistivity area is not available, can managed with other types of soil but for high resistivity soil area to attain low ground grid resistance may be difficult and costly. This paper also discuss about minimization of this difficulty without change the soil characteristic.

Keywords: Grid resistance, ground grid design, ground potential rise GPR, ground rod, Earth pit, soil resistivity, current division factor, step potential, touch potential