INDUCED VOLTAGE ON AN OVERHEAD WIRE ASSOCIATED WITH INCLINED RETURN-STROKE CHANNEL MODEL EXPERIMENT ON FINITELY CONDUCTIVE GROUND

Experiments on the lightning-induced voltage waveforms on an overhead wire influenced by an inclined return stroke channel are carried out o utdoors with a reduced-scale model, The measured voltages are compared with those calculated by solving the Telegrapher's equation in combin ation with numerical calculation of electric fields associated with re turn-stroke currents, and the validity of the calculations is verified . The,effect of the ground conductivity on the lightning-induced volta ge 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 wife, the influence of the ground conductivity on the induced voltage waveform is significant irrespective of the inclin ation or the direction of the lightning channel. The degree of the inf luence is dependent on the Inclination and the direction of the channe l when a return stroke hits the ground on the side of the overhead wir e.