Induced field on an overhead line and LPS due to lightning

This paper presents the computational simulation results of transient current and voltage induced on an overhead line and on a lightning protection system from direct and indirect lightning return stroke using the time domain of G. P. Caixeta (2000) and the Agrawal et al. approach. Two cases were implemented here: (a) When lightning directly strikes the overhead line and the induced voltage and current at both systems (overhead line and LPS) are simulated; and (b) when lightning strikes 300 meters along the line and the induced voltage and current are also simulated. All processes involved in simulations are carried out using the TLM (transmission line matrix) technique in one dimension. The return stroke channel is simulated as a straight vertical line over a perfectly conducting ground plane, and described as a double-exponential function. The electric field due to transient current is calculated by the expressions in Cartesian coordinates, developed by G. P. Caixeta (2000), along the overhead lines and cables of the LPS. The coupling method is represented by sources distributed along the lines and cables M. Rubinstein et al., (1989) that is adapted by TLM technique. The results were compared with other works where the magnitude and the waveforms are in good agreement with each other.