Experimental and Simulation Verification of the Effects of Different Metal Particle Impurities on the Electrical Properties of Alumina/Epoxy Composites for GIL Insulators

This paper studies how metal impurities in alumina fillers affect the electrical properties of epoxy/alumina composites, which are used for gas-insulated transmission line insulators. The paper prepares samples with aluminum, copper and iron particles, and measures their glass transition temperature, dielectric spectrum and temperature spectrum, power frequency breakdown strength and volume resistivity. It also uses COMSOL Multiphysics software and Latin hypercube sampling technique to model and simulate the dielectric constant and electric field distribution of the samples. The results show that metal impurities lower the volume resistivity and breakdown strength, increase the dielectric constant and loss, and distort the electric field of the composites. The simulation results match well with the experimental data. The paper offers theoretical and experimental guidance for improving the electrical properties of epoxy/alumina composites.