Effects Of Nano Particles On Tracking Failure Phenomenon Of Epoxy Nanocomposite Under DC Voltage

With the voltage levels increasing, more and more insulating material in highvoltage equipments suffer with tracking failure phenomenon. As a commonlyinsulating material, epoxy plays an important role in the insulation of electricalequipments. Once the tracking failure occurred on the surface of epoxy, it may leadsto short circuit, blackouts, fire, explosion accidents and other serious consequences.With the inorganic nanometer particles added in epoxy, the resistance to trackingfailure will change greatly. After modified by doping inorganic nanometer particles,the insulation of epoxy will change greatly. Therefore, the research on resistance totracking failure of epoxy nanocomposites has a very important significance for thepractical application.Epoxy/MgO and Epoxy/Al₂O₃made in our laboratory was employed as the testsample in this paper. Based on the needle-board electrode, with the NH4Cl electrolyteto simulate the filthy environment on epoxy surface，the tracking failure phenomenonunder dc voltage condition was investigated. The main achievements are as follows:（1） By the study of discharge light distribution on the sample surface and changein the number of drops, it found nano-size MgO particles can slow down the processof tracking failure. Nano-size MgO particles can also reduce the area of trackingfailure and weight loss. The influence of nano-size MgO particles on dischargecurrent was studied by using a recursive plot analysis and fractal dimension method.Results showed that the resistance to tracking failure of the epoxy was improved bynano-size MgO particles, especially the5wt%mass fraction has the best results.（2） The influence of Al₂O₃nanoparticles on the resistance to tracking failure ofepoxy was studied. It found that Al₂O₃nanoparticles can slow down the process oftracking failure. And Al₂O₃nanoparticles can also reduce the area of tracking failureand weight loss. By the study of discharge light distribution on the sample surfaceand the number of drops, it found Al₂O₃nanoparticles can slow down the process oftracking failure. Al₂O₃nanoparticles particles can also reduce the area of trackingfailure and weight loss. By using a recursive plot analysis and fractal dimensionmethod, the influence of Al₂O₃nanoparticles on the regularity features of discharge was studied. Results showed that the Al₂O₃nanoparticles can improve resistance totracking failure of the nanofilled epoxy, especially the5wt%has the best results.