Based on the wind turbine icing observation records from November 2017 to February 2022 in a mountain wind farm in Hubei Province

and combined with high-precision meteorological reanalysis data

interpolation is carried out by comprehensively considering the terrain conditions of wind turbines

on the basis of the hourly meteorological data of each fan

the changes of the meteorological factors during the icing and melting stages are analyzed

and the critical values of the meteorological factors at the icing and melting stages are obtained. 1） during the icing stage of the fan

the air temperature decreased continuously

the relative humidity increased continuously

and the wind speed did not fluctuate too much before and after the icing stage. 2） during the icing stage of the fan

the air temperature rises continuously and reaches the peak at the time of ice melting; the relative humidity decreases continuously and reaches the lowest value at the time of ice melting; the wind speed remains stable and significantly decreases compared to the icing stage. 3） the critical meteorological conditions for the ice coating of the fan are that the air temperature at the height of the wheel hub is about 0-2 ℃

the wind speed is in the range of 4-6 m/s

there is little or no precipitation

and the relative humidity is over 95%; The critical meteorological conditions for ice melting of the fan are that the air temperature is above 4 ℃ at the height of the wheel hub

the wind speed is in the range of 2-4 m/s

and the relative humidity is less than 90%.