Synoptic Characteristics and Ice Prediction Model Test Based on an Ice Event of Ultra-High-Voltage Transmission Lines in the Northwest of Guangdong in 2022

This February 2022 is a very serious ice-covering of ultra-high voltage transmission lines in Guangdong area, with a maximum ice-covering thickness of 32.68 mm. In this paper, using ERA5 reanalysis information and ice-covering monitoring system information provided by the Southern Power Grid, we discuss the causes of this ice-covering in depth from the weather circulation situation, temperature and humidity vertical layer changes, and meteorological conditions, and compare and analysis the ice-covering forecast model prediction results with the actual ice-covering data. It is finally found that the effect of cold vortex in northeast region and western Pacific vice high makes the horizontal trough turn vertical, guiding cold air southward and converging with wet air in Guangdong, which is favorable for ice cover generation; the results of model comparison show that the temperature decreases rapidly from above 0 to below 0, which is easy to generate ice cover, and the model forecast results match with the actual ice cover process, and the error comes from the unstable forecast accuracy of meteorological elements temperature and wind speed.