Induced voltage on an overhead wire associated with inclined return-stroke channel-model experiment on finitely conductive ground

Abstract

Experiments on the lightning-induced voltage waveforms on an overhead wire influenced by an inclined return-stroke channel are carried out outdoors with a reduced-scale model. The measured voltages are compared with those calculated by solving the Telegrapher's equation in combination with numerical calculation of electric fields associated with return-stroke currents, and the validity of the calculations is verified. The effect of the ground conductivity on the lightning-induced voltage waveform is studied based on numerical calculations and is found to be dependent on the position of the return-stroke channel relative to the overhead wire. When a return stroke hits the ground close to the end of the overhead wire, the influence of the ground conductivity on the induced voltage waveform is significant irrespective of the inclination or the direction of the lightning channel. The degree of the influence is dependent on the inclination and the direction of the channel when a return stroke hits the ground on the side of the overhead wire.