Improvement of breakdown strength by additives and curing conditions on XLPE insulation for power cable

In This work, dielectric strength of XLPE insulation with lamellar densities varied by means of additives and curing conditions was investigated. To increase lamellar density of XLPE insulating material, two kinds of additives were used and cooling rates were controlled as curing conditions. TEM and X-ray diffraction was used to investigate the degree of lamellar density varied by additives. For breakdown strength of XLPE insulation with additives and different cooling rates, the mold-type cable specimens were made and evaluated with Weibull plot parameter. From the results, it is observed that the additives improve the lamellar density. In addition, we found that the dielectric strength of samples manufactured under slow cooling rate is higher than rapid cooling one. TEM and XRD analysis showed that the density in the XLPE insulation at the interface significantly affects dielectric strength of XLPE insulation.