Observation of Polymeric Insulator Deterioration Due to Local Arc Discharges

Silicone rubber, commonly used as the housing material for polymer insulators, undergoes surface degradation, such as erosion, when exposed to local arc discharges. Investigating the progression of this degradation is crucial for understanding the aging characteristics of polymer insulators and evaluating their remaining service life. In this study, we conducted a saltwater dripping test to efficiently induce local arc discharges by dripping saltwater onto polymer insulators under alternating current voltage. We observed significant surface degradation phenomena, including surface roughening and erosion. These observations are essential for understanding the aging process of polymer insulators and for developing methods to evaluate their remaining service life.