Reducing failure in power transition lines using a novel nano silica/silicone rubber hydrophobic coating of glass insulator

Abstract

Flashover failure is a significant issue that reduces the ability to insulate the glass insulators in power transition lines. The main reason is the surface contaminates, which increases the conductivity of the surface leading to flashover occurrence. A sol-gel method was used to create a hydrophobic surface on the high voltage glass insulator, preventing dusty or salty water droplets from adhering to its surface. The cold spraying technique was utilized to build up a thin nanocomposite hydrophobic layer on the glass insulator containing different percentages of nanosilica particles, such as 23%, 33%, and 44% with the potting compound silicone substrate. The wettability test, hardness, roughness and dielectric strength of the produced nanocomposite were investigated. Furthermore, the surface morphology of the prepared silicone rubber/nanosilica hydrophobic nanocomposite was occurred using the FESEM analysis. The findings show that silicone rubber/33% nanosilica exhibits the best hydrophobic behavior, with a contact angle is more than 133.3˚. Also, the change in dielectric strength was 16.4% when adding 33% percentage of the nanosilica. The flashover test was also performed, and it was discovered that the leak current between the coated and uncoated samples were differed significantly. Using a 60 kV voltage load, the leak current of the coated sample with a hydrophobic nanocomposite was decreased to 2.4 mA, whereas the untreated sample was 3.1 mA. These findings may assist to enhance the hybrid nanocomposite as hydrophobic surface made of silica nanoparticles/silicone base preventing contaminants from adhering on the insulating glass in high voltage power transition lines.