Abstract:According to the spetio temporal distribution characteristics of the power equipment pollution flashover and the geographic features in Henan, duration of the contamination, temperature inversion near the ground surface, relative humidity and wind are firstly identified as import contributions to pollution flashover disaster. Then the composite thresholds of these factors are respectively assessed using the methods of spatio temporal matching, statistical analysis of threshold and model based on the flashover hazard data and meteorological observations. The comprehensive meteorological model for pollution flashover established here considers well the atmospheric conditions that breed the disaster, including high humidity, weak wind, less rain in the early period and stable atmospheric stratification near the surface. The model established here fits the relationship between the meteorological environmental conditions and the pollution flashover events well. The validation results indicate that the model can capture the disaster events with the false alarm rate less than 10%. The spatio temporal characteristics of the annual mean power flashover events calculated from the 30 year historical observations show high frequency over the northeast of Henan during wintertime. Thus, the findings in this paper would provide a scientific support for the early warning of power equipment pollution flashover in this region.