Analysis and recurrence of lightning stroke accidents for three gorges 500-kV transmission lines

Lightning stoke has become the first environmental factor which influences the safety of 500-kV power grid in Three Gorges near area. To grasp the operation level of transmission lines, analyze and recur the lightning stroke accidents, and summarize the characters, are the bases of finding and guiding the effective lightning protection measures. In this paper, a method of recurrence for lightning stroke accidents of transmission lines was researched. Over 10 times of 500-kV lightning stroke accidents for about 15 lines in Three Gorges near area during the year of 2007~2009 were recurred and analyzed. Combined with the lightning detection information and simulated calculation, the range of lightning shielding incidence points were concluded. The conclusions and characteristics of accident recurrence and analysis would provide good references for the lightning protection performance improvement.