Self-stabilized discharge filament in plane-parallel barrier discharge configuration: formation, breakdown mechanism, and memory effects

Abstract

Single self-stabilized discharge filaments were investigated in the plane-parallel electrode configuration. The barrier discharge was operated inside a gap of 3 mm shielded by glass plates to both electrodes, using helium-nitrogen mixtures and a square-wave feeding voltage at a frequency of 2 kHz. The combined application of electrical measurements, ICCD camera imaging, optical emission spectroscopy and surface charge diagnostics via the electro-optic Pockels effect allowed the correlation of the discharge development in the volume and on the dielectric surfaces. The formation criteria and existence regimes were found by systematic variation of the nitrogen admixture to helium, the total pressure and the feeding voltage amplitude. Single self-stabilized discharge filaments can be operated over a wide parameter range, foremost, by significant reduction of the voltage amplitude after the operation in the microdischarge regime. Here, the outstanding importance of the surface charge memory effect on the long-term stability was pointed out by the recalculated spatio-temporally resolved gap voltage. The optical emission revealed discharge characteristics that are partially reminiscent of both the glow-like barrier discharge and the microdischarge regime, such as a Townsend pre-phase, a fast cathode-directed ionization front during the breakdown and radially propagating surface discharges during the afterglow.

Review of surface transient charge measurement on solid insulating materials via the Pockels technique

“…It should be emphasised that transient charge plays a fundamental role in explaining the basic phenomena of volume or surface discharge. For instance, the spatially fixed re-ignition during consecutive discharge breakdowns is called 'memory effect', as discussed in Chapter 5, which is currently considered as a result of long-lifetime metastable species (bulk effect) and deposited surface charge (surface effect) [81]. Another case when the first stochastic discharge develops into a stable and repeatable mode after hundreds of continuous pulses is called 'accumulation effect', which is affected by the concentration of specific long-living species [82].…”

“…Surface charge memory effect plays an important role in the stabilisation of filamentary discharge [81]. It was observed by Wild et al that the charge reversal starts in the centre of a residual charge spot where the electric field is highest, and extends outwards gradually [63], as shown in Figure 10.…”

“…Pockels crystals, acting as the dielectric barriers, were inserted into DBD reactors to hold and detect the transferred charge. Usually, the optical reflecting measurement system is constructed as shown in Figure 9, with a metal mirror as the ground electrode and a transparent ITO layer as the high-voltage electrode [54,56,60,61,67,81]. Various dielectrics, such as borosilicate glass, mono-crystalline alumina, magnesia and PE film were attached on Pockels crystals to investigate influence of material properties on transient behaviour of surface charge in different modes [27,59].…”

“…Surface charge memory effect plays an important role in the stabilisation of filamentary discharge [81]. It was observed by Wild et al.…”

Very large-scale gap distances of atmospheric pressure dielectric barrier glow discharge using semiconductor materials

“…Hence, the current increases at a slower rate in the negative voltage phase. The time between points "1" and "2" or points "5" and "6" indicates the discharge-off phase, and Q decreases linearly with time, resulting from transporting in the outward direction and in the annular direction of the wall charge [42]. By increasing V a more, the current increases because of the more charge accumulating on the material surface.…”