Safe operation of power transformer is seriously affected by the overheat defect of oil impregnated paper (OIP) bushing. In order to calculate the operating temperature of the OIP bushing accurately, the temperature correlation of the conductive parts in the OIP bushing is considered. A three-dimensional eddy current field finite element analysis model of the OIP bushing is established. The Joule heat losses of the conductive rod, flange, oil conservator and equalizing ball of the OIP bushing under different load currents are obtained. Considering the convection heat transfer and thermal radiation effects on the surface of the bushing porcelain, the losses are input into the two-dimensional temperature field analysis model of the OIP bushing as heat sources. The thermal field distributions of bushing under different load current conditions are calculated. Temperature rise prediction of the conductive rod in the OIP bushing is realized, which has reference significance for the safe operation of OIP bushing.

oil impregnated paper bushing, eddy-current field, thermal field, finite element method, temperature rise prediction