Analysis of an Actual Corrosion Damage Defect of Composite Insulator on 1000 kV Transmission Line
In order to analyze the cause of an actual corrosion damage defect of a composite insulator on a 1000 kV line,test analysis of the defective insulator was carried out by means of infrared test,dissection,hydrophobicity test,equiva-lent salt density test,permeability test and water diffusion test.The results show that heat can be generated at location of corrosion and that magnitude of the heat generated depends on corrosion severity and test location.The corrosion damage is caused by air gap at the shed-sheath interface of the composite insulator.The interfacial air gap at causes partial dis-charge under the effect of high field intensity,and long-term effect gradually leads to generation and expansion of the elec-trical corrosion area.Based on causes of corrosion and heating characteristics,suggestions for subsequent operation and maintenance measures are proposed.
composite insulatorcorrosion damageshedair gapoperation and maintenance suggestion