Title: Impact of Shield Wire failure and Back flashover on String Insulator of a 132 KV Transmission line
Authors: Sunday Ugemuge Gabriel Ebiowei Moses
Volume: 9
Issue: 11
Pages: 60-66
Publication Date: 2025/11/28
Abstract:
The study examines how lightning stroke, particularly a 100-kA strike, generate over-voltages in a 132 kV transmission line, especially when the lightning directly hits a phase conductor or tower. These strikes create fast-front transient surges that travel along the line and can induce high voltages capable of causing insulator flashover or back flashover. Using the Electric Circuit Simulator (ECS), the research analyzes the behavior of these surges, the resulting tower-top voltages, and the critical conditions that lead to insulation failure. It also evaluates the role of tower footing resistance in dissipating lightning currents to ground under both direct and indirect strokes, and before and after shield wire failure.