Effects of Nano- and Micro-Filler on Water Diffusion and Leakage Current of GRP Composites

摘要

Non-ceramic composite insulators (NCIs) based on glass fiber-reinforced polymer (GRP) rods have been widely used in transmission and distribution applications for several years worldwide. Their advantages over traditional porcelain insulators are numerous; yet, under certain in-service conditions, harsh environmental parameters such as high moisture contents, elevated temperatures, electrical fields, and acidic conditions can cause severe damage to the insulators and in particular to their core material. For instance, brittle fracture of the GRP rods can occur, leading to the failure of the insulators if either water or nitric acid is allowed to penetrate inside the units. The ingress of water into the composite rods can also alter the dielectric properties of the insulators making them less suitable for high-voltage insulation applications [1-3]. It is reported that electrical properties of GRP composites strongly depend on amount of moisture absorbed [4, 5]. Water absorption may also change the structure of epoxy-based composites leading to adverse impact on the mechanical, electrical, and thermal properties [6, 7].