Natural Pollution Considerations in Designing Outdoor Composite Insulators

Insulators playa vital role in the outdoor terrestrial power grid. Their performance is adversely affected by pollution. The insulator surface contamination leads to pollution flashover, causing failure of the system. Composite insulators are used in outdoor power applications due to their hydrophobic surface. Pollution types are environmental (natural), artificial (unnatural), or a combination of both. The geometrical profile design is important to lessen the pollution effect. Hence, the design must be chosen carefully, so the insulator can cope with the dominant type of pollution in their service area without flashing over. Depending on the literature, this work focuses on investigating the effect of geometric profile design on the composite insulator performance under different natural pollution conditions. Accordingly, a particular composite insulator geometric profile is recommended for each type of natural pollution. The uniform flat shed profile is recommended for composite insulators serving in areas prone to solid natural pollution while the alternating inclined shed profile is recommended for liquid naturally polluted areas. Furthermore, the end fitting sealing design is studied via electric field distribution analysis, and recommendation is also given.