Influence of SiO2 and ZrO2 Nanocomposite on the AC Breakdown Strength of Cross-linked Polyethylene (XLPE)

Evolution of high voltage (HV) cables has increased significantly over the last decade due to emerging of HVDC applications. Thus, polymer nanocomposites become one of the main research areas for exploring the potential of insulating materials in terms of dielectric strength enhancement. This is due to many convincing results of nanocomposites capabilities reported by researchers. For this, this work explores the influence of Silicone Dioxide (SiO2) and Zirconium Oxide (ZrO2) on the dielectric strength of Cross-linked Polyethylene (XLPE). The mixture between the filler and the base polymer is one of the major factors for improving the characteristic of the nanocomposites. The unfilled XLPE and nano-filled (1wt%, 3wt%, 5wt% and 10wt%) XLPE are prepared from powder to pallets using extrusion and crosslinking processes. These methods have been used to prepare nanocomposite samples into thin layers of 1mm. The samples are tested under AC breakdown performance of unfilled and nano-filled XLPE according to ASTM D149 standard. The results observed an improvement of breakdown performance at the low usage of nanofillers. A comparison based on SiO2 and ZrO2 has shown different behaviours. Therefore, this study investigates the effect of these nanofillers on the performance of nanocomposites under both AC performance.