Estimation of Voltages and Currents Due to Lightning Strokes to Transmission Lines

This paper presents an improved equivalent circuit representation for the lightning stroke to estimate the magnitudes and waveshapes of currents and voltages through transmission system components due to lightning strokes. Results indicate that arrester currents can go as high as 130kA with a front time of the order of 15us, while the arrester potentials are substantially rectangular lasting anywhere upto 60 us. Transformer potentials are initially oscillatory exceeding the BIL. This could be dangerous. Thus, this work was successful in improving the equivalent circuit representation of the lightning stroke and highlighted interesting areas for further research