Effects of lightning impulse front time on substation grounding system performance

Muhammad Adnan (Institute of High Voltage and Current, School of Electrical Engineering, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia)
Zulkurnain Adul Malek (Institute of High Voltage and Current, School of Electrical Engineering, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia)
Nur Syazwani Mohd Din
Muhammad Irfan Jambak (Department of Electrical Engineering, Faculty of Engineering, Universitas Sriwijaya Ogan Ilir 30662 Sumatera Selatan, Indonesia)
Zainuddin Nawawi (Department of Electrical Engineering, Faculty of Engineering, Universitas Sriwijaya Ogan Ilir 30662 Sumatera Selatan, Indonesia)
Muhammad Abu Bakar Sidik (Department of Electrical Engineering, Faculty of Engineering, Universitas Sriwijaya Ogan Ilir 30662 Sumatera Selatan, Indonesia)

Indonesian Journal of Electrical Engineering and Computer Science
Vol 20, No 2: November 2020

The role of the grounding system in the safety of the power system and protection of personnel is obvious during an unexpected short circuit or lightning discharge at the substation. The aim of this work is to analyze the effects of several parameters: lightning impulse front time, soil resistivity and types of grid materials on the grounding system of the Substation. The ground potential rise (GPR), touch voltage and step voltage of a 50 m x 60 m grounding grid buried at a depth of 0.5 m were computed using CDEGS when injected by impulse with different front times. Results show that the shorter the front time of lightning impulse waveform, the higher the value of GPR, touch voltage and step voltage. Meanwhile, when the value of soil resistivity is increased, the value of GPR, touch voltage and step voltage is also increased. Lastly, different types of grid conductor materials give different values of GPR, touch voltage and step voltage. However, it can be said that the differences are too small to be of any significance.