Statistics and Analysis of Lightning Flashovers of Transmission Lines during 2000~2007

In order to analyze the correlativity between the lightning flashover amount and the time factors, about 425 times lightning flashover on 187 lines in 10 power supply companies of 220 kV and 500 kV transmission lines during 2000~2007 are investigated in this paper. The correlativity between the lightning flashover amount and the time factors is analyzed. According to the lightning stroke accidents investigation records, the lightning flashover amount of transmission line increases from the year of 2000 to 2007. In each year lightning flashovers mostly happen in the month of June, July and August. Similarly in each day the flashover amount also varies with the time of day obviously. These lightning flashovers mainly occur during 14:00
_~
21:00 in the afternoon. The analysis results in this paper have a good agreement with the meteorological observations. And these results provide good reference for the lightning protection work in power system.