Partial Discharge Endurance of Epoxy / SiC Nanocomposite

Partial discharge (PD) endurance of epoxy/SiC nanocomposite was investigated in comparison with that of epoxy/silica (SiO₂) nanocomposite. Filler contents were 1 wt%, 2 wt%, 3 wt%, 4 wt% and 5 wt% in epoxy/silicon carbide (SiC) nanocomposite. Evaluation was made by erosion depth and eroded cross sectional area in its profile measured with the laser surface profilometory. It was confirmed that epoxy can be much improved in its PD erosion performance by adding SiC nano fillers to a similar degree as compared to SiO₂ nano fillers. Additionally, close inspection of the cone-shaped erosion profile clarifies that the shape of erosion profile is broader in epoxy/SiC nanocomposite than in epoxy/SiO₂ nanocomposite. This indicates that SiC fillers tend to remain less stuck on the surface after exposure to PDs than silica fillers. One of the authors has proposed that nanometric segmentation by inorganic nano-fillers is effective to increase PD resistance. It can be assured that such function is also operative in the case of SiC as nano-fillers.