Experimental Studies on Surface Discharge Dynamics and Decay under Different Voltage Waveforms and Electrode Shapes

Abstract: This paper studies the development and decay of surface discharge under various voltage waveforms and electrode shapes in air at atmospheric pressure. The electro-optical Pockels method is utilised to measure and quantify the distribution of surface charge. Charge is deposited on the surface of the Bismuth Silicon Oxide (BSO) sensing crystal from a high voltage needle or mushroom electrode. Sinusoidal, square pulse and ramp voltage waveforms of different polarities are generated in order to investigate the differences in the total surface charge, inception voltage and distribution pattern of positive and negative discharges. The total charge deposited can be found by integrating the post-processed charge density over the entire surface. This technique also enables the study of charge decay with time.