| Abstract:Based on the detailed information on transmission line lightning strike and meteorological elements data before transmission line lightning strikes from 1990 to 2017 in Shijiazhuang,utilized frequency,linear trend and fluctuation amplitude,the temporal and spatial distribution characteristics of transmission line lightning strikes,variation of timing wind,pressure,air humidity,air temperature and ground temperature before transmission line lightning strikes in 6 hours were analyzed.By defining the cumulative occurrence frequency of transmission line lightning strikes, the meteorological element characteristic index of the occurrence of transmission line lightning strikes was determined, and the accuracy of the prediction of the level of transmission line lightning strikes in 2018 was tested by comparing the EC numerical prediction with the automatic station live data.The results show that,transmission line lightning strikes had increased significantly in recent years,occurring from June to August with August mostly, occurring mainly from afternoon to night with 16-21 mostly.Transmission line lightning strikes mainly occurred in the western mountainous areas with being in Jingxing’s central area, which gradually decreased from northwest to southeast.On the whole,the maximum wind direction on the ground affected by the convergence of cyclones rotated anticlockwise from SE through NE to NW.When air pressure and relative humidity was rising, or when air temperature and surface temperature was dropping, lightning strikes on transmission lines occurred frequently and fluctuation amplitude was greater;when air pressure and relative humidity was dropping, or when air temperature and surface temperature was rising, the frequency of lightning strikes on the transmission line was less and fluctuation amplitude was smaller. The study can provide scientific reference for predicting and preventing local transmission line lightning strikes accurately. |
