Numerical Study on the Thermo-Electric Analysis of Carbonization in Epoxy Insulators

This study investigates the degradation of electrical insulation performance caused by carbonization in epoxy insulators used in high-voltage transmission systems. A numerical analysis was conducted using finite element analysis-based ANSYS Workbench and Q3D Extractor to evaluate changes in electric field intensity, current density, Joule heat, and charge density as the carbonized length increases. The results show that as carbonization progresses, the electric field intensity, current density, and Joule heat increase significantly, leading to a deterioration of insulation performance. When the carbonization length reaches 90 percent of the insulator, the electric field intensity sharply increases, indicating a critical degradation point. Complete carbonization penetrating the insulator results in insulation failure due to the formation of a conductive path, although dielectric breakdown does not occur under the rated operating voltage of 600V. These findings highlight the importance of early detection and monitoring of carbonization to prevent insulation failure in epoxy insulators.