Improvement of breakdown and flashover properties against thermal aging of oil paper insulation through addition of TiO ₂ nanoparticles

TiO2 nanoparticles can improve the electrical performance of oil paper insulation. In this study, 10 nm were prepared and dispersed into transformer oil, then immerse pressboards in it to obtain nanofluid impregnated (NP). Its thermal aging was accelerated together with reference sample at 130°C for 36 days. Analyzing acid value polymerization degree, surface topography, AC breakdown strength, flashover characteristics potential decay characteristics. It observed that reduce strength oil. However, degree appearance NP (OP) during did not differ significantly. During process, energy level pressboard traps shifted first towards shallow gradually deep. all stages, voltage always higher or close OP. The mechanism improving oil–paper insulation is discussed from perspective water molecules by-products adsorption introduction by nanoparticles.