Some Observations on the Character of Corona Discharges in Short Gap Spaces

Corona discharge results, obtained with a number of gases under atmospheric pressure using plane-parallel metallic and dielectric electrodes placed between 0.05 and 9.00 mm apart, are discussed. With short gap spacings, deviations from the pulse or spark-type discharge mechanism are observed to occur in particular when dielectric surfaces are involved; the deviations are characterized usually by the appearance of pseudoglow discharges, which exhibit properties that are common to both pulse and glow discharges. The practical significance of pseudoglow discharges in relation to corona measuring techniques, utilizing conventional pulse discharge detectors, are considered both on a short-and long-term test basis.