The light and current pulse regimes in the DC prebreakdown processes of liquid dielectrics

DC prebreakdown current pulses with their associated integrated electrical charges and light emissions have been recorded in tetraester, transformer oil, and cyclohexane for point-plane electrode arrangements. kHz and MHz non-point polarity-dependent current and light pulses were observed. It was noted that, although there was general correlation between the two pulse systems (current and light), there were certain cases in which correlation was absent. The results obtained suggest that, although both electronic and gaseous processes occur complementarily in the prebreakdown chain, electronic activity is dominant.