Effect of two-layer soil model on the design of substation grounding system.

The substation grounding system is an important part of the electric power system as a part of the protection system to prevent equipment damage due to more severe fault currents by flowing fault currents to the ground. Therefore, the design of the substation grounding system must comply with the applicable standards. One thing that is very influential on the design of the substation is the soil type resistance where the substation stands. At a certain location, it is often found that several types of soil have different resistivity (non-uniform), namely the two-layer soil model. This paper discusses two methods used to determine the parameters of the two-layer soil resistivity, namely the Sunde graph method and modeling with the CYMGRD software. To determine the level of security in the design of substation grounding, the parameters used in this paper are the limit values of the step voltage and the touch voltage which have been tested in each case of the two-layer soil resistivity modeling. [ABSTRACT FROM AUTHOR]