Breakdown characteristics of high pressure xenon lamps

Abstract

An investigation of the breakdown of high intensity discharge (HID) lamps filled with xenon at pressures from 0.1 to 5 bar is presented. Three power supplies were used in order to provide voltage rates of increase covering about four orders of magnitude from 5 mV ns−1 to 100 V ns−1, the latter being typical for electronic ballasts driving commercial HID lamps. Customized lamps ensure a volume breakdown between the tungsten tip electrodes of the lamp. Voltage and current waveforms were measured by means of electrical probes and the transient optical radiation was captured by a fast camera system. The breakdown voltage increases with growing pressure and voltage rate up to several 10 kV. Additional UV illumination decreases the breakdown voltage and reduces its mean variation. The experimental results were reproduced with good agreement by a fluid model taking into account the electron energy balance. The model shows an ionization front propagating towards the cathode. The front moves due to continuous field compression and relies on electron avalanches initiated by secondary electrons at the cathode.

Derivation of Moment Equations for the Theoretical Description of Electrons in Nonthermal Plasmas

“…Nonthermal plasmas are widely used in many technical applications including plasma display panels, energy saving lamps, devices for microbial decontamination and ozonizers [1][2][3][4]. They are characterized by low gas temperatures g in the range from 300 to 1000 K and comparatively high mean electron energies T e  between 1 and 10 eV, where 1 eV corresponds to temperature of 11605 K. Computer simulations of electric gas discharges producing nonthermal plasmas are used since many years to get a deeper understanding of fundamental processes and to improve technical devices [5][6][7][8][9][10]. In order to describe all phenomena taking place in the discharge mechanism, in principle, a mathematical model comprising the kinetic Boltzmann equation [11]       has to be solved in combination with Maxwell's equations for the electric field E and the magnetic field .…”

Facilitating breakdown in noble gases at near-atmospheric pressure using antennas

“…The respective relative influences of these properties grow with the pressure of the gas studied. This is why the breakdown process in lamps, especially mid-and high-pressure lamps, is still under investigation [1][2][3][4][5][6][7][8][9][10][11].…”

The Role of Metastables in the Formation of an Argon Discharge in a Two-Pin Geometry

“…These modeling efforts have described the ignition process in noble gas pressures ranging from 10 to 90 torr (13-120 mbar), where the discharge is glowlike and not constricted. Research in the field of high pressures of noble gases has been mainly experimental [4], [17]- [19], and it has been shown that, due to high voltages, the criterion for glow-tostreamer transition is fulfilled and that the discharges forming under these conditions are filamentary streamerlike ionizing channels. The experiments have also shown that the breakdown voltage rises with pressure and that the speed of propagation of the discharge rises with applied voltage and decreases with the increase in pressure.…”

“…Recently Wendt et al [19] qualitatively described the discharge in Xe at 0.1-5 bar at an electrode distance of 5 mm. The pulse rise rate was varied between 10 and 1000 V/ns.…”