Influence of different oil-paper configurations on the electric field distribution simulation of the internal insulation of converter transformer

Abstract

Converter transformer is an important equipment in HVDC system and it is the key to the stable operation of the whole power transmission and distribution system. Unlike the traditional AC transformer, the oil-paper insulation of converter transformer will receive both AC and DC voltage. So the requirement for the structure design of oil-paper insulation system will be more stringent. It is of great engineering significance to study the electric field distribution of converter transformer and to study the influence of different oil-paper insulation configuration on the electric field distribution in the internal insulation of converter transformer. In this paper, first, an oil-paper insulation structure of converter transformer is established and electric field distribution under AC/DC composite voltage is studied. Then change the thickness and layers of pressboard, the distance of oil channel and the oil-paper ratio to get different oil-paper configurations. Use the simulation software to calculate the electric field distribution under the different oil-paper configurations. Finally, the influence of different oil-paper configuration on the electric field distribution of internal insulation structure of converter transformer is analysed which will provides significant reference for the internal insulation design of converter transformer.