CONDITION ASSESSMENT OF A FIELD-AGED 150 kV HTV SIR SUSPENSION INSULATOR FOLLOWING FLASHOVER

Condition assessment results are presented for a field-aged 150 kV HTV SIR suspension insulator following its flashover due to bird nesting activity. The insulator, equipped with arcing horns, was operated for 10 years in a coastal transmission network under heavy environmental pollution. In order to evaluate flashover effects on insulator housing, several macroscopic and microscopic diagnostic techniques were employed including visual inspection, hydrophobicity classification, Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) analysis. Arcing affected the morphological structure and elemental composition, thus also hydrophobicity of the housing surface in proximity to arcing horns. The protection offered by the arcing…