[Paper Review] Dielectric Barrier Corona Discharge Anomaly by Ionic Wind under Unipolar Voltage Excitation

Gan fu|arXiv (Cornell University)|Mar 4, 2026

High voltage insulation and dielectric phenomena0 citations

TL;DR

This paper investigates an anomalous back-discharge movement in dielectric barrier corona discharges under unipolar half-sine voltages, explained with an ionic-wind model and corroborated by experiments on multiple insulators and a FEP cable. It presents a numerical model and PRPD analyses showing how surface charges, material properties, air gaps, and geometry influence PD patterns.

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.

Motivation & Objective

• Investigate anomalous back-discharge movement during relaxation in DBCD under negative unipolar half-sine excitation.
• Understand the role of ionic wind and surface charge dynamics on PD patterns across materials and geometries.
• Quantify how insulation thickness, air gap, material resistivity, and geometry affect back-discharge amplitude and position.

Proposed method

• Use unipolar half-sine voltage waveforms with a 90 ms relaxation period to study back-discharge movement.
• Employ time-resolved PD measurements with MATLAB processing and PSA-based PRPD visualization.
• Test six insulation materials (PTFE, PE, PC, PVC, pressboard, and FEP cable) in needle-plane and needle-cable geometries.
• Develop a numerical model for the needle-plane geometry incorporating ionic wind effects and surface-charge dynamics.
• Analyze PD patterns across three back-discharge stages (S1, S2, S3) at chosen trigger voltages (7.6, 10, 13.6 kV).
• Apply Peek’s inception voltage and Kaptsov’s hypothesis to frame corona initiation in the model.

Experimental results

Research questions

• RQ1 How does ionic wind influence the distribution and movement of back-discharge clusters during the relaxation period under negative unipolar half-sine excitation?
• RQ2 How do insulation thickness, air gap length, material resistivity, and geometry affect PD amplitude and back-discharge position?
• RQ3 Why is back-discharge movement markedly different under negative versus positive half-sine excitation?
• RQ4 What are the relationships between applied voltage level, surface potential, and back-discharge amplitude across materials?
• RQ5 Can a predictive model reproduce PRPD patterns and back-discharge stages observed experimentally?

Key findings

• Back-discharge clusters move across the relaxation period with increasing voltage under negative half-sine excitation, eventually disappearing at higher voltages.
• Average PD amplitude decreases with higher voltage due to stronger ionic wind reducing surface charge density.
• Materials with higher surface resistivity show lower back-discharge amplitudes, indicating surface-charge dynamics dominate pattern formation.
• Thinner insulation requires lower trigger voltages for each back-discharge stage due to changes in net electric field and surface potential.
• Air-gap length governs Ionic-wind propagation; larger gaps raise trigger voltages and generally reduce PD amplitude; very small gaps suppress back-discharge in favor of streamer discharge.
• Needle-cable geometry yields similar PD distribution trends but at higher required voltages due to reduced active surface.”
• Pressboard shows no back discharge under the study conditions due to higher conductivity and charge dissipation, illustrating material-dependent dominance of charge mechanisms.