Detailed Explanation Of Insulator Knowledge--factors Of Pollution Flashover
1 Effect of altitude
Due to the low atmospheric pressure at high altitude, discharge is very likely to occur, and the arc is thicker. After the AC passes zero, the circuit is very likely to discharge, and the arc is easy to reignite and difficult to extinguish. Therefore, the insulation of power transmission and transformation equipment operating at high altitude and low air pressure should be strengthened. When calculating insulation coordination, its influence must be fully considered, and its pollution flashover voltage should be appropriately increased. Generally, when the altitude is above 3000 m, the pollution voltage value should be increased by about 25%.
2 high voltage standoff insulators Effect of ice and snow
high voltage epoxy Ice and snow have different effects on pollution flashover voltage. After experimental research by relevant scientific research departments, epoxy resin insulator When pollution first occurs and then ice forms, under the same salt density, its pollution flashover voltage can be increased regardless of whether it is in a frozen state or in a melted state. If the ice is fully melted, its withstand voltage remains unchanged. Normally, ice and snow are often contaminated in the air and then frozen on the high voltage epoxy resin, at which time the withstand voltage value is the lowest, and flashover accidents are very likely to occur. At present, countries around the world are paying close attention to the impact of high altitudes and heavy ice areas on the electrical strength of high voltage standoff, and are actively carrying out research.
3 Impact of acid rain and acid mist
Due to different geographical environments, atmospheric pollution causes acid rain and acid mist to exist in some areas to varying degrees. Since the conductivity of acidic pollutants increases with the decrease of pH value, the flashover voltage of insulators is greatly reduced. With the acceleration of industrialization, the situation of atmospheric pollution of power grids has become more severe, so it is necessary to improve environmental awareness, increase law enforcement efforts, and take technical measures to strengthen the management of power transmission and transformation equipment to avoid flashover accidents.