An Analytical Approach to Assess the Influence of Shield Wires in Improving the Lightning Performance Due to Indirect Strokes

Abstract

The lightning performance of an overhead line due to indirect strokes is a measure of its ability to resist to surges produced by nearby lightning. The estimation of the lightning performance generally requires a huge number of calculations requiring computationally intensive simulations. In this paper, we present an approach that uses analytical expressions, leading to a very significant reduction of the required computer resources. By this analytical approach, we investigate the lightning performance under different line arrangements; the study is also devoted to assessing the improvement that can be obtained by addition of underbuilt shield wires to arrangements in which only upper shield wires are typically used: it is shown that such a measure can lead to significant enhancements in terms of lightning performance.