This study aims to develop a new type of environmentally friendly high thermal conductivity anti-corrosive coating for transformers. Graphene, carbon nanotube, carbon nano-horn and ultrafine graphite powder mixture are used to modify the thermal conductivity of the coating on the transformer surface. The thermal conductivity and microstructure of traditional solvent-based coatings, water-based epoxy zinc-rich coatings, and modified high thermal conductivity coatings are analyzed. Results show that the modified high thermal conductivity coating has the smallest thermal resistance (2.51℃/W) and the highest thermal conductivity (1.3460 W/(m·K)), indicating that its thermal conductivity is significantly better than those of the other two traditional coatings. This enhancement is mainly related to the optimization of the type of thermal conductivity and the improvement of coating density. After adding high thermal conductivity filler to the waterborne epoxy zinc-rich coating, a ballistic-diffusion scheme of heat transfer is formed. On the other hand, the added high thermal conductivity material fills the pores and cracks in the coating, which greatly improves the density of the coating and builds a heat transfer channel between transformer metal and external environment. The transformer temperature rise simulation experiment shows that the high thermal conductivity coating can reduce the top layer temperature rise of transformer oil by 1.67 K.

transformer  /  water-based epoxy zinc-rich coatings  /  high thermal conductivity materials