Analisis Sistem Pentanahan Grid Gardu Induk pada Dua Lapis Tanah

Abstract

The substation is a terminal that connects the transmission lines and distribution lines. One of the security systems used in substations is using a safe and good grounding system. The substation grounding system is a system that connects conductors, equipment bodies and installations with the ground, where it is not uncommon for the grounding equipment to be planted in two or more layers of soil so that the fault currents generated can be channeled directly to earth to maintain the safety of power system equipment and human safety. located near the substation. The most commonly used grounding system at substations today is a combination of grid and rod. This study analyzes the two-layer earth grounding system at the Sarulla 2 x 250 MVA 275 Kv substation using the ASPIX 3.1 software and compares the existing design with the square grounding system model, then finds out the effect of the depth of grid planting and the distance between grid conductors. to touch voltage and actual step voltage, GPR and grounding resistance with the same distance between grid conductors based on IEEE std. 80-2013. The permissible touch voltage on the grounding system of this substation is 1403.4 V for a body weight of 50 Kg and 1899.4 V for a body weight of 70 Kg and the permitted step voltage is 5025.6 V for a body weight of 50 Kg and 6801.8 V for a body weight of 70 Kg. The actual touch voltage is 1069.2 V and the actual step voltage is 894.9 V with a total length of conductor used is 4320 m. The greater the distance between the conductors used, the value of the actual touch voltage and step voltage, GPR and grounding resistance will also be greater. The deeper the grid is buried underground, the smaller the touch voltage and actual step voltage, GPR and grounding resistance will be.