Analysis of lightning-induced current and voltages on 500 kV EHV double circuit transmission lines of type DL3/spl deg/ and DT 20/spl deg/ in lightning protection system

This paper presents a method to consider of the current and voltage induced on 500 kV EHV double circuit transmission lines of type DL3/spl deg/ and DT 20/spl deg/ in lightning protection system. These analyses are based on modeling lightning return stroke as well as on coupling the electromagnetic fields of the stroke channel to the line. The ground conductivity influences both the electric field as well as the coupling mechanism and hence the magnitude and wave shape of the induced voltage. The presence of other conductors affects the induced voltage of a conductor, the analysis of current and voltage induced on an overhead line by lightning strokes to nearby ground. The simulation results show that this study analyses for assuming ground as a perfect conductor and for the stabilization of estimating such lightning induced outages of a long distance power transmission system.