Evaluasi Tegangan Sentuh dan Tegangan Langkah Sistem Pentanahan GRID Akibat Perubahan Resistivitas Tanah pada PT. PLN (Persero) Gardu Induk 150 kV Selayang

Abstract

The grounding system is a conductor connection system that connects the electrical system, equipment body, and installation with the ground so that it can protect humans from electric shock and protect installation components from the dangers of abnormal voltage or current. Therefore, it is very necessary to carry out calculations that can see the extent of the touch stress and step stress. The grounding system most often used today in substations is a combination of grid and rod. This research will analyze the grounding system at the Selayang 150 kV substation using ETAP 19.0.1 software and compare the grounding system in dry and wet conditions with the same distance between grid conductors based on IEEE Std. 80-2013. Data for carrying out calculations was obtained from UPT (Transmission Implementation Unit) Medan as the implementer of the construction of the 150 kV substation in Selayang, North Sumatra. This thesis examines the touch voltage and step voltage at the Selayang 150 kV substation as changes in soil resistivity (dry ground conditions and wet ground conditions. From the results obtained for the actual touch voltage, the results were 1,214.6 V for dry ground conditions and 1,174.7 V wet ground conditions. Furthermore, the actual step voltage results were 1,657.6 V for dry ground conditions and 1,603.2 V for wet ground conditions. Judging from the comparison values above, the Selayang 150 kV substation grounding design meets the requirements, because it does not exceed the touch voltage. The permitted step voltage is 1,403.15 V for dry ground conditions and 1,402.96 V for wet ground conditions, and the permitted step voltage is 5,024.36 V for dry ground conditions and 5,023.6 V for wet ground conditions