Research on the Propagation Characteristics of High Frequency Partial Discharge Signal in Transformer

Abstract

Abstract In order to study the information contained in the high frequency partial discharge and the influence of transformer winding on the propagation of partial discharge signal, this paper injects high frequency small signals into the external leads, internal winding and enclosing screen of 110kV three-phase double-winding transformer to simulate the external discharge, inside and outside of the winding discharge to study the propagation characteristics of transformer partial discharge signal. The study shows that the partial discharge signal is coupled from one to others, and the signal can be detected at each detection end when partial discharge occurs; the partial discharge signal consists of high-frequency component and low-frequency component, the high-frequency component is mainly propagated through the capacitance between the windings, and the low-frequency component is mainly propagated through the windings; The polarity of the first wave of the time domain signal is different when the discharge of the internal winding of the transformer propagates to each detection point, the polarity of the first wave of the time domain signal is the same when the discharge of the outside winding propagates to each detection point. Among them, the discharge of the outside winding mainly propagates through the capacitor, and the low-frequency components of each detection terminal are seriously attenuated.