A Comparative Study of Energy Loss in Glass and Polymer Insulators: Influence of Environmental Conditions and Insulator Aging

Leakage current along high-voltage insulator surfaces is a factor contributing to power loss, particularly under polluted and humid environmental conditions. The two most often used materials in overhead transmission lines (OHTLs), glass and polymer insulators, are compared in this study for power losses due to leakage current (LC). Sensors installed on OHTLs were used to monitor leakage current and weather parameters in real time at two stations both located near highway roads, which exposed to similar environmental conditions. Each insulator string consisted of one insulator per string at the first station and seven insulators per string at the second station. Power losses were evaluated across all three phases for both materials. The results demonstrate that polymer insulators exhibit significantly lower power losses compared to glass insulators under similar environmental conditions. On average, polymer insulators reduced power loss by approximately 81% compared to glass insulators. Additionally, the form factor calculated was higher for polymer insulators (26.04) compared to glass insulators (4.78), indicating better insulation. Furthermore, high humidity and precipitation were found to cause more pronounced increases in LC for glass insulators, likely due to their hydrophilic surface properties, making polymer insulators a more efficient option for minimizing power loss in such environments.