Lightning risk assessment and lightning protection design retrofit for a typical transmission line

Transmission lines traversing regions with complex climatic and topographical conditions are frequently subjected to lightning-induced trip-out faults, posing significant threats to the reliable and stable operation of power systems. Based on the computational parameters extracted through deep mining of lightning big data, this study conducts a lightning risk assessment for transmission lines and proposes corresponding lightning protection design modifications. The lightning protection level of a typical transmission line is evaluated, and a series of improvement measures—such as installing surge arresters, adjusting the shielding angle of overhead ground wires, reducing grounding resistance, and enhancing insulation levels—are proposed based on the assessment results. The effectiveness of the proposed protective measures is further validated through case studies on two representative high-risk towers, demonstrating that the developed computational framework can provide guidance for differentiated lightning protection design modifications of transmission lines.