Multiple-spark discharge occurring between a charged conductive plate and a grounded sphere electrode

The characteristics of spark discharges occurring between a conductive square plate charged by induction charging and a grounded sphere electrode have been investigated experimentally for various plate sizes and charging voltages. The spark discharge having double or multiple peaks in the current waveform occurred from a positively charged plate with particular size and charging voltage. The double-spark discharge was reproducible. The peak values of both the first and the second peak significantly depended on the plate size and charging voltage. From the observations of the luminous aspects and the induction current due to the discharge event, it was found that the double-spark discharge would be caused by the incomplete first spark with relatively less conductive spark channel.