Investigation on the Frequency Dependence of the Correlation Between Discharge Current and Gap Voltage in Helium Dielectric Barrier Discharges at Atmospheric Pressure

This article presents a systematic investigation on the frequency dependence of the discharge current $J_{g}$ versus the gap voltage $V_{g}$ in the atmospheric-pressure helium dielectric barrier discharges (DBDs) by means of numerical simulation based on a 1-D fluid model. The DBDs are excited by a sinusoidal voltage with frequencies from several tens of kHz to MHz. This article concludes the following. There is a characteristic frequency $f_{c}$ located in a range, smaller than the lower limit of which the $J_{g}$ – $V_{g}$ curve universally behaves as a pinched hysteresis loop, and higher than the upper limit of which it changes to a nonpinched one, and an estimation of $f_{c}$ has been given. Smaller than the lower limit of $f_{c}$ , in spite of its $J_{g}$ – $V_{g}$ pinched hysteresis loop, the discharge plasma part in the DBD cannot be described as a memristor, but exhibits a memory effect. With the increase in frequency, the $J_{g}$ – $V_{g}$ curves display two typical shapes similar to a hockey stick and a quasi-triangle, corresponding to a Townsend discharge and a glow discharge, respectively. Higher than the upper limit of $f_{c}$ , the $J_{g}$ – $V_{g}$ curve is no longer a pinched hysteresis loop, and its evolution with frequency is in a change between symmetry and asymmetry. These evolution behaviors of the $J_{g}$ – $V_{g}$ curves are mainly due to the charges remained in the gap when the frequency is higher.