Some aspects of overhead transmission lines lightning performance estimation in engineering practice

Abstract

Summary The paper presents some aspects of overhead transmission lines (OHL) modeling for lightning overvoltages estimation in engineering practice. Different models of elements are compared, and sensitivity analysis is performed with the aim to investigate their influence to the OHL insulation stress due to lightning discharges. Elements are modeled according to international technical documents covering this field. Great influence of applied model of air flashover to the lightning current, sufficient to cause back flashover, is noticed. Calculation results obtained with different combinations of element models have been compared and large deviations are noticed. The models of elements for lightning overvoltages estimation should be carefully chosen to achieve reliable estimations. Constant resistance model of tower grounding and voltage-time curve model of air breakdown must be avoided in calculations, despite the fact that they are suggested in many technical documents dealing with lightning overvoltages at OHL. Copyright © 2015 John Wiley & Sons, Ltd.