In this paper, the transmission line tower response and behaviour are described when a lightning stroke terminates on the tower apex. The accompanying overvoltages on different points on the tower and under different conditions are covered. The effect of different tower representation and modelling on the overvoltages produced and the tower travel time is also included. The effect of back flashover on a phase conductor terminated by a GIS for a simplified tower is also investigated.

Electrical power systems, Transmission line tower modelling, Lightning surges,
Gas Insulated Substation (GIS).