On the Role of Shield Wires in Mitigating Lightning-Induced Overvoltages in Overhead Lines - Part II: Simulation Results for Practical Configurations

Abstract

In the companion Part I, the theory relevant to the role of shield wires in mitigating lightning-induced overvoltages in overhead lines has been analyzed and clarified. A more consistent meaning has been assigned to the concept of Shielding Factor by introducing two innovations compared to the current literature: the first one concerning the distinction between <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">internal</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">external</i> parameters, and the other one concerning the point along the line where to assess the mitigation effect. Thanks to this new approach, uncertainties seen in the literature have been sorted out, and the Shielding Factor has been shown to be a parameter which can be precisely quantified. However, our new contribution was applied to a schematic (unrealistic) configuration: a line with a shield wire grounded at only one point. This Part II is precisely devoted to confirming the results obtained in Part I, by applying the proposed approach to more realistic and practical line configurations, namely a line with multi-grounded shield wire, and a line equipped with laterals too.