Design of a Lightning Protection System for an Overhead 3 kV DC Electrified Railway Line: A Case Study from South Africa

A protection scheme is proposed for the 3 kV DC railway, in Kwa-Zulu Natal province, a region with high lightning occurrence density. The surge was sought by implementing three metal-oxide arresters and an overhead ground wire. purpose of these determined their location circuit points that are vulnerable to adverse effects: arrester installed protect insulators between lines supporting metallic mast, point contact stationary power supply wire train, apparatus associated running tracks (return rail). An isolated earthing system explored, effects impedances footing resistances discussed. voltage dropped across relevant components energy absorbed simulation software Simulink. These results compared railway outfitted designed mechanisms. Lightning currents injected into using Heidler function where parameters compliance standards. It observed mechanisms defend susceptible specified level. This demonstrates success design accordance levels (73.3 kV) equipment withstand capabilities (a basic insulation level 143 kV). offers margin 95%. largest percentage overshoot 39%, this value substantiated reflection phenomena.