Analysis and Test of Insulation Terminal Defects in Electrical Strength Test of Model Cable

When the model cable is used for electrical strength test, the handling of the terminal is a difficult point. Improper handling can easily cause the breakdown of the internal cable of the terminal, leading to unsuccessful testing. In this paper, with the help of COMSOL finite element analysis software, a simulation analysis of several defects commonly encountered in the terminal processing of the electrical strength test of the model cable, Including the electric field distribution at defects on the surface of the cable insulation under the oil terminal and water terminal, such as: scratches, bumps, external shielding fractures, copper chips, etc. The results show that the oil terminal can effectively weaken the field strength distortion caused by scratches on the insulation surface and copper chips, and reduce the overall field strength in the model cable insulation inside the terminal, but it will increase the field strength distortion at the fracture of the external screen. which is the main reason for the breakdown. The water terminal can effectively weaken the field strength distortion at the fracture of the external screen, but it will increase the field strength distortion caused by the scratches on the insulation surface and copper chips. The internal defects of the model cable insulation are the main reason for the breakdown. The influence of the bumps under the two terminals is not obvious. This research provides a guiding basis for the terminal processing methods of using model cables for electrical strength testing in the future.