Improvement of Semicon-interface of an XLPE Power Cable with Interface Diffusion Method

Abstract

An Improvement Method of breakdown strength at the interface between an insulation layer and a semiconducting layer in a XLPE power cable was proposed. The Method was named as “Interface Diffusion Method” and is based on an additive mixed into semicon layer of an XLPE power cable. The authors found that tha additive diffused into insulation layer during cross-linking proces in XLPE cable manufacturing and the additive improves the lamellar orientation at the interface and forms a Diffusion layer the additive at the interface resulting increase of the breakdown strength. The method was applied to an XLPE power cable with 9mm insulation with successful results. The cable passed withstand voltage test and a long-term insulation performance test as 154kV cable. In addition to these cable test, material analysis was done on the interface region of the cable such as TEM analysis and FT-IR analysis. The material analysis showed that lamellar orientation in the XLPE at the interface was improved and diffusion layer of the additive was formed as expected.