Dielectric Barrier Corona Discharge Anomaly by Ionic Wind under Unipolar Voltage Excitation

TL;DR

This study investigates the unusual back discharge movement in dielectric barrier corona discharges under unipolar voltage, using ionic wind modeling and experiments to analyze its behavior and effects on partial discharge patterns.

Contribution

It provides a theoretical and experimental analysis of back discharge phenomena under unipolar voltage, revealing polarity-dependent behaviors and the influence of dielectric and geometric parameters.

Findings

Back discharge can be activated at low voltages.

Polarity significantly affects discharge patterns.

Dielectric thickness influences PD amplitude.

Abstract

An anomalous back discharge movement phenomenon is induced by a set of dielectric barrier corona discharges (DBCD) at unipolar half-sine voltage waveforms, where the back discharge has a time delay that relates to the applied voltage level. An ionic wind model is employed to analyze the physical behavior. Theoretical explanation and quantitative analysis are presented in this study based on abundant experimental results of 5 typical insulating materials and a FEP insulating cable. A numerical model is derived, which indicates that the back discharge can be activated under a relatively low potential voltage level in this study. The results highlight that the back discharge movement phenomenon behaves distinctly under half-sine voltage with negative polarity, yielding a significantly different partial discharge (PD) pattern with positive polarity. Besides, PD amplitude dependent on dielectric thickness is demonstrated by plotting in phase resolved partial discharge (PRPD) pattern. Furthermore, comparative experiments are conducted with respect to the variation of air gap length and dielectric geometry, manifesting different influences on PD amplitude.