Probabilistic evaluation of lightning performance of overhead transmission lines, considering non-vertical strokes

This paper represents a developed procedure for the evaluation of flashover rates caused byboth lightning vertical and non-vertical strokes on transmission lines, using a monte carlo method. themain goal of this paper is to increase the accuracy flashover rates through the accurate modelling ofnetwork components, such as footing impedance, the transmission tower and chain of insulators, andalso simulation of lightning non-vertical strokes. modelling network components, statistical parametersrelated to lightning and a problem-solving algorithm are described. parametric studies using thisprocedure can also be performed to determine the sensitivity of the flashover rate with respect to someparameters of the return stroke and the transmission line. simulation results obtained using matlab andthe atp/emtp show that considering the lightning non-vertical instead of vertical strokes leads to a betterevaluation of the lightning performance of transmission lines.