On the parameters for representing tower-footing electrodes in studies of the lightning performance of transmission lines

Abstract:
Different parameters used for representing tower-footing electrodes in studies of lightning performance of transmission lines were analysed and their values were calculated for usual arrangements of electrodes, in a wide range of soil resis-tivity and respective usual range of electrode lengths. The results showed the parameters values to be quite different and that using the impulse impedance determined from the low-frequency resistance and impulse coefficient is preferable.