Evaluation of the effects of voids in electrical cables using COMSOL Multiphysics software

This work investigates the impact of voids in three-phase cables. Voids in cross-linked polyethylene (XLPE) insulated cables are identified as weak points, causing operational changes due to partial discharges. Changes in electric field strengths and current density were evaluated in cable models with Copper (Cu) and Aluminum (Al) cores, containing voids in both the insulating layer and the conductor. Therefore, we applied the COMSOL Multiphysics software based on the Finite Element Method (FEM), to carry out simulations with a voltage of 1 kV, frequency of 60 Hz with alternating current (AC), with a phase change of 120°, in the time domain. With the results, it was possible to obtain a comparative analysis with cables without voids. The study identified that voids generate intense and non-uniform electric fields, generating significant changes in the electric field and current density, offering essential information about the performance of cable systems in practical situations.