Effect of ZnO Nanofiller in the XLPE Matrix on Electrical Tree Characteristics

The effect of nanofillers on the electrical tree behavior of polymeric materials, such as epoxy resin and polyethylene, has been investigated. Thus, research on electrical tree behaviour is extended but limited only to pure crosslinked polyethylene (XLPE) cable. Electrical tree properties are yet to be explored under various types of nanofillers in XLPE. In this paper, the electrical tree characteristics of XLPE containing zinc oxide (ZnO) nanofiller was reported. The nanofiller concentrations in XLPE were varied to 0.5, 1.0, and 1.5 wt%. Needle-plane electrodes were employed with 2 mm gap between the electrodes. A digital camera and microscope system were used to observe the structure and growth of electrical tree in XLPE. The tree inception voltage (TIV) of XLPE increased with the addition of ZnO nanofiller. The propagation length of tree growth improved compared with the unfilled XLPE. The TIV for the samples with 0.5, 1.0, and 1.5 wt% ZnO nanofiller improved by 7.69%, 14.65%, and 7.16%, respectively, relative to the unfilled XLPE.