Flashover Simulation in a 500 Kv Transmission Line Considering Propagation Time Between a Ground Wire and a Phase Conductor

The mutual surge impedance of an overhead line has been conventionally modeled by resistive coupling. The propagation time between conductors of a transmission line has not been considered in the conventional model of the mutual surge impedance. A tower model has been represented by highly accurate model using distributed-parameter lines. The surge propagation along the tower body and arm is considered for steep front lightning currents. As a result, the time difference between induced voltage due to the mutual surge impedance and surge along the tower is clearly observed. The propagation time of mutual surge impedance should be considered in accurate lightning surge analysis. This paper discusses a flashover in a 500 kV transmission line considering the propagation time between a ground wire and a phase conductor. The transmission line is assumed to be a semi-infinite length of line. The simulation method can be carried out using an electrical circuit theory.