Surge arresters are critical assets in power transmission and distribution networks, providing protection against overvoltages caused by lightning strikes and switching operations. Their external insulation system—whether porcelain or polymeric—must maintain adequate dielectric strength under all environmental conditions. However, in regions characterized by high airborne pollution (industrial emissions, coastal salt fog, desert dust, or agricultural contaminants) combined with frequent and heavy rainfall, the external insulation of surge arresters faces a particularly severe threat: rain flashover.
Metal-oxide surge arresters (MOSAs) are critical assets in power transmission and distribution networks, providing primary protection against overvoltages caused by lightning strikes and switching operations. Their reliable operation directly influences system availability and equipment safety.
Zinc oxide surge arresters (MOA) are critical assets for overvoltage protection in power systems. However, moisture ingress due to sealing degradation remains the predominant cause of in-service failures. This article presents a systematic live diagnostic framework combining infrared thermography, resistive leakage current measurement, and online monitoring technologies, alongside a comprehensive sealing and moisture prevention strategy encompassing material selection, structural optimization, and operational maintenance.
Lightning strikes remain one of the primary causes of unscheduled outages in transmission networks worldwide. In Malaysia, Japan, and China, lightning accounts for the majority of line trips and equipment failures.
IntroductionComposite insulators, with silicone rubber (SIR) as the primary shed material, have been widely deployed in high-voltage transmission and substation applications due to their lightweight, excellent hydrophobicity, and superior pollution flashover performance.
Porcelain insulators remain a backbone of high-voltage transmission and distribution systems worldwide. Despite their reputation for long service life, aging populations—many now exceeding 30–40 years in service—present growing reliability challenges. This paper presents a comprehensive framework for assessing the remaining life of aged porcelain insulators and provides a decision-support methodology for batch replacement planning. The framework integrates multiple assessment approaches—including fuzzy evaluation, Bayesian probabilistic modeling, Weibull distribution-based failure analysis, and Cigré TB 306 guidelines—to deliver actionable insights for utility asset managers.
