Tuning the potential distribution of AC cable terminals by stress cone of nonlinear conductivity material

High voltage cables now have been widely applied in electric power systems. A prefabricated rubber stress cone is the key part of high voltage cable terminal, and its property is the main factor in determining whether the high voltage cable operates safely. In this paper, the finite element numerical simulation is applied to analyze the distribution of electric field intensity. Instead of using materials with fixed conductivity, materials with nonlinear conductivity are used as the insulation material for rubber stress cones. The polymer composites with nonlinear conductivity that depends on applied electric fields can smartly smooth the nonuniform electric fields in insulation components of power systems through varied material parameters with the electric field. Combined with theoretical analysis, we can determine the parameters range of nonlinear conductivity materials. By comparing the electrical field distribution of different materials, it is found that nonlinear conductivity polymer composites can effectively improve the electric field at the rubber stress cone face and the junction of stress cone terminal, which is of significance in the development of higher voltage cable in the future.