AC and DC Electro-Thermal Aging Analysis of Polymeric Housed Surge Arresters

The study investigates the effects of long-term electro-thermal aging on polymer-housed metal oxide surge arresters, which are crucial for protecting electrical systems from voltage surges in both HVAC and HVDC networks. The present work mainly focuses on assessing the performance degradation and reliability of the surge arresters under simulated field conditions, including temperature variations and polarity reversals. The Arrester samples were subjected to AC and DC stress, with periodic polarity reversals in case of DC, at an elevated temperature of 60°C for 750 hrs. Leakage current measurements and hydrophobicity (wettability class) tests were conducted to evaluate the aging effects. The results indicated significant differences in leakage currents and hydrophobicity degradation between AC and DC stressed samples, with AC stressed samples showing higher leakage currents and more substantial loss of hydrophobicity.