The Effects of Surge Arrester Location and Tower Footing Resistance on 230/63 kV Substation Under Lightning Overvoltage

Substations feed power to consumers through overhead transmission and distribution lines. A high voltage substation is an assemblage of electrical components including switchgear, busbar, transformers, etc. For protection of these equipment and stability purpose, overvoltage protection is very important. Lightning is one of the most serious causes of overvoltage. Occurring lightning surge near the substation can leads to severe harm to substation equipment and great outage in the network. The lightning wave arriving in substation can be influenced by factors such as substation structure, arresters location, the lightning waveform and location of lightning surge and tower footing resistance. The analysis of lightning stroke and its location, surge arresters role and influence of its position and tower footing resistance by EMTP-RV are the purposes of this paper. Simulation shows absence of surge arresters can be dangerous in few cases such as backflashover produced by first tower near the substation.