Partial Discharge and Breakdown Strength Characteristics of Cross-Linked Polyethylene/SiO2 Nanocomposites

The partial discharge and dielectric breakdown strength characteristics are among the parameters measured for insulation development, especially for the power cable. Cross-linked polyethylene (XLPE) is a type of host polymer used widely to insulate the conductor part of the medium and high voltage cables. The resilience of the cable commonly depends on the performance of the polymer to insulate the conduction part efficiently. However, the dielectric performances of the XLPE degraded due to various aging factors. Adding the nanofillers into the XLPE matrix might enhance the dielectrics properties of the XLPE. In this study, silica (SiO2) nanofillers have been added into the XLPE matrix with various loadings to improve the partial discharge and dielectric breakdown strength. The loadings of the silica nanofillers were varied at 1, 3, and 5 wt% to identify the most effective nanofillers loading in improving XLPE nanocomposites' durability. The results show that XLPE nanocomposites with 1 wt% silica nanofillers obtained the lowest value of the maximum PD magnitude compared to other compositions. The dielectric breakdown strength of XLPE increased significantly as 1 wt% of silica nanofillers have dispersed. However, the trend was saturated when the nanofiller loading at 3 wt% and slightly decreased at 5 wt% of the nanofiller loading.