Experimental determination of dielectric barrier discharge capacitance

Abstract

The determination of electrical parameters (such as instantaneous power, transferred charge, and gas gap voltage) in dielectric barrier discharge (DBD) reactors relies on estimates of key capacitance values. In the classic large-scale sinusoidal-voltage driven DBD, also known as silent or ozonizer discharge, capacitance values can be determined from charge-voltage (Q-V) plot, also called Lissajous figure. For miniature laboratory reactors driven by fast pulsed voltage waveforms with sub-microsecond rise time, the capacitance of the dielectric barriers cannot be evaluated from a single Q-V plot because of the limited applicability of the classical theory. Theoretical determination can be problematic due to electrode edge effects, especially in the case of asymmetrical electrodes. The lack of reliable capacitance estimates leads to a "capacitance bottleneck" that obstructs the determination of other DBD electrical parameters in fast-pulsed reactors. It is suggested to obtain capacitance of dielectric barriers from a plot of the maximal charge versus maximal voltage amplitude (Q(max) - V(max) plot) in a manner analogous to the classical approach. The method is examined using measurements of current and voltage waveforms of a coaxial DBD reactor in argon at 100 mbar driven by square voltage pulses with a rise time of 20 ns and with different voltage amplitudes up to 10 kV. Additionally, the applicability of the method has been shown for the data reported in literature measured at 1 bar of nitrogen-oxygen gas mixtures and xenon.

Performance evaluation of non-thermal plasma on particulate matter, ozone and CO2 correlation for diesel exhaust emission reduction

“…In order to extract and analyse important electrical properties such as power consumption of the DBD reactor, the V-Q Lissajous method as a standard process for diagnostics of DBD systems has been used [29,30]. To measure Q, an auxiliary capacitor is placed in series with the DBD.…”

Energy of Reactions in Atmospheric‐Pressure Plasma Polymerization with Inert Carrier Gas

“…Now, in the case of AP discharges, particularly for PP reactions, neither of these generally apply: First, AP PP processes necessarily use a flow of carrier gas, wherein that of the monomer is generally highly diluted (typically in the parts per thousand, ‰, range); regarding power measurements in AP plasmas, the present authors have strong reasons to believe that such measurements are far from being simple, certainly not those involving AP DBDs. For example, many workers use Q – V plots , also known as Lissajous figures; first introduced by Manley in 1943, this technique is now known to require considerable caution. …”

Energetics of Reactions in a Dielectric Barrier Discharge with Argon Carrier Gas: III Esters

“…In preceding articles, we reported that several groups attempted to apply the W / FM concept to AP PP, using values of W determined from Lissajous figures or related techniques . This entails at least two difficulties: (i) accurate power measurements in DBD plasmas are error‐prone; (ii) even if W is determined with care, it includes both the carrier gas and the monomer. We showed that this can lead to a multifold overestimate of W / FM , hence to erroneous conclusions .…”