CORONA TRANSMISSION-LINE ENERGIZED BY VERY SHORT PULSE VOLTAGES AS APPLIED IN ELECTROSTATIC PRECIPITATORS

The corona-producing characteristics of a corona wire energized by a very short pulse voltage superposed on a dc base voltage are investigated in consideration of its application in electrostatic precipitators. A 'formation region' of the pulse-induced negative corona is determined in terms of a V//B - V//P domain where V//B represents the dc base voltage and V//P the pulse peak voltage. A pulse voltage propagates in a form of a traveling wave along a transmission line out of an elongated corona wire and collection plates. It produces streamer coronas and loses its energy during propagation and finally becomes inactive so as not to produce coronas. As a result, the longitudinal distribution of the ionic current shows a decay towards the end of the line. An effective pulse energy, W//E is defined as the energy needed to produce uniform current distribution on all the collection plates. This value of W//E amounts to 0. 8 J for a 200-m corona line. A pulse peaking technique to squeeze more corona energy from the pulse after corona-induced deterioration is tested using partial and total reflections, and its effectiveness is confirmed. A matched feeder concept to allow uniform distribution of pulse power to a number of corona transmission lines is presented.