Electro-Thermal Coupling Analysis of OIP Capacitor Bushing Insulation Modified by Nano-TiO2

With the rapid development of high-voltage transmission engineering technology, oil-immersed paper (OIP) capacitor bushings, as one of the main components in the transmission system, are facing unprecedented challenges for the composite insulation reliability. At present, the optimization designing of bushing insulation performance is mainly focusing on the new material and structure. However, there are few reports on the application of nano-modified technology for the transformer bushing. In this paper, the oil-immersed paper modified by nano-TiO2 particles with different mass fractions were prepared, relative permittivity of samples was measured at various temperatures, and electro-thermal coupling model of OIP capacitor bushing was established. The experimental results show that nanoparticles can reduce the relative permittivity of the samples, and the using of oil-impregnated paper modified by nanoparticles can reduce the electric field strength outside the bushing core and the electric field strength variance of the bushing.