Streamer Currents, Emitted Lights and Energies into Dielectric Liquids Submitted to DC Stress

The present work is aimed at the survey of currents, emitted lights and energies associated to positive and negative streamers propagation in three dielectric liquids: mineral oil, tetra-ester and toluene in a point-plane electrode arrangement under High Voltage Direct Current (HVDC) stresses. The applied fields range between those corresponding to low energy level discharges till those relative to high energy arcing. The influence of the applied voltage level and the gap distance on the shape and magnitude of these characteristics are also investigated. The approach is also oriented towards the analysis of the frequency behavior and inter-correlation function between currents and corresponding emitted lights.