Analysis of q-n and φ-q characteristics of partial discharge in several electrode systems

This paper describes some new aspects of the reration between partial discharge characteristics and several void model structures in terms of statistical features of partial discharge pulse magnitudes against applied voltage phase. Newly proposed parameters here are the skewness and kurtosis of a φ-q pattern (applied voltage phase versus cycle mean discharge magnitude) and have been found to represent the partial discharge characteristics of various kinds of void structures more destinctively than conventional partial discharge parameters such as maximum apparent discharge maginitude qmax and mean discharge current Iq do. Typical dependence of the skewness and the kurtosis on applied voltage in three kinds of IGI (Insulation-Gas-Insulation) void structures are discussed.