Time-evolution phenomena of electrical tree partial discharges in Magnesia, Silica and Alumina epoxy nanocomposites

Resistance to electrical tree-induced degradation is one of the common ways of characterising solid dielectrics. This paper presents experimentally obtained distinct time-evolution patterns of electrical tree partial discharges (PDs) in epoxy nanocomposites of Magnesia, Silica and Alumina. Plots of the electrical tree PD magnitudes recorded every second from inception to complete failure show that the PD magnitudes in the nanodielectric epoxy are generally smaller than in neat epoxy. Furthermore the PD magnitudes and phase-resolved-patterns (PDPRP) in the nanodielectric epoxy evolve through distinct classes as the trees propagate to complete failure. The experimental findings confirm existing knowledge and give new insights into the understanding of electrical treeing phenomena in nanodielectrics.