Three-Dimensional Electro-Thermal Analysis of a New Type Current Transformer Design for Power Distribution Networks

In recent years, the new type design of current transformer with bushing structure has been widely used in distribution network system due to its advantages miniaturization, high mechanical strength, maintenance-free, safety and environmental protection. The internal temperature field is an important characteristic parameter characterize thermal insulation aging performance transformer, mainly derived from joule heat generated by primary side guide rod after flowing through current. Since electric environment a transient changes slowly time as steady under actual conditions, it more complex necessary study electrothermal coupling (CT). this paper, 3D simulation model for based on electric-thermal established using finite element method (FEM) software. Considering that conduction process CT conduction, convection radiation, three different kinds boundary conditions such solid transfer condition, condition surface radiation are applied CT. Through created above, rise characteristics gradient inner conductor current, ambient temperatures core diameters studied. Meanwhile, hottest maximum difference calculated. According this, position weak determined. research results can provide reference factory production transformer.