Study on the Dislocation Defects of the Stress Cone in 10kV Cable Joints Based on Electro-Thermo-Mechanical Multiphysics Coupled Fields

This study establishes 2D electro-thermal-mechanical finite element simulation coupling models to analyze six defect models under various stress cone installation conditions, ranging from insufficient to excessive installation. The results show that distortions in the electric field intensity, temperature field, and stress field occur between the fracture in the outer semiconducting layer and the inflection point of the stress cone. When the fracture in the outer semiconducting layer exceeds the inflection point of the stress cone, it leads to electric field concentration, causing minor discharge phenomena at the insulation interface. The maximum stress was observed at the inflection point of the stress cone under insufficient installation conditions. By identifying the critical zones for stress cone dislocation defects and understanding the interplay between the electric, thermal, and mechanical fields, this research provides valuable insights for designing more resilient cable joint installations and maintenance protocols.