Study On Fatigue Property Of High Voltage Cable Terminal

Electrical power has become widely used energy because it can transform all kinds of energy. The electric power load is extremely uneven in our country, so we need a wide range of high voltage transmission network for electricity transmission. Cable terminal is the weakness of high voltage electricity grid. The mechanical property, especially fatigue property of high voltage cable terminal is very important for the stability. In this paper, the fatigue property of high voltage cable terminal were studied by theoretical analysis, experimental testing and numerical methods. The main contents are as follows:The combined method of experimental test and numerical simulation of fatigue property was proposed, at the basic features of rubber prefabricated stress cone high voltage cable terminal structural.According to national standards, the tensile fatigue test of two materials made up rubber prefabricated stress cone of high voltage cable terminal that are electro-insulating rubber and semiconducting rubber was conducted. The fatigue property results of two materials were achieved and the basic fatigue parameter, S-N curve, was fitted.Three dimensional finite element analysis models of stress cone were established. The comparison results of finite element fatigue simulation analysis and experiments of rubber material indicated that using finite element method to simulate the fatigue property of rubber is reliable.Three dimensional finite element analysis models of high voltage cable terminal were established. High-voltage cable terminal is simulated using mechanical field finite element methods in initial installation condition while mechanical-electric-thermal field finite element methods in working condition.The comparison results of experimental test and finite element analysis show that finite element simulation is effective and accurate. Maximum value of high voltage cable terminal stress appear at the interface of the cable insulation.Combining the fatigue experiments, the fatigue simulation results show that cable insulation interface at junction of two materials should be most easily destroyed and high voltage cable terminal can fully meet the requirements of 50 years work time limit.The stress distribution and fatigue property of new hardware fittings of high voltage cable terminal is researched using theory calculation and finite element simulation. The comparison results are fitted well. The calculation and simulation results of the new hardware fittings of high voltage cable terminal show that it doesn't significantly affect the overall fatigue conclusions.