Research on Lightning Activity at High Altitude in Tibet

Tibet is in the southwest of Qinghai-Tibet Plateau, which owns expansive territory. As the transmission line between Tibet and Sichuan has been connected, the total number of important power transmission channel become larger, and lightning trip-out faults are more serious. Average altitude of Tibet is above 4000m, which cause different lightning activity in China. According to researching lightning Activity characteristic in Tibet, the basic lightning parameters can be got, which is very important for the designing and maintenance of the important transmission line. This passage count the lightning activity in Tibet from 2014 ~ 2018 year: firstly, by contrasting the total number of ground flash in each year, the strongest lightning activity happened in 2013 year, which is 0.229 times/(km
²
·a); Secondly, by contrasting the difference of lightning in different area, the strongest lightning Activity happened in Lhasa and Shan-nan; Thirdly, by researching the cumulative probability distribution of lightning current amplitude, the middle lightning current is about 29kA; At last, the lightning density distributing graph of 500kV transmission lines in Tibet were analysed, the higher area were Qusum county, Gyaca county, Chagyab county and Markam county.