Corona-plasma triggered pseudospark discharges

This paper reports on a novel pseudospark triggering technique using a corona-plasma electrode to feed initial electrons into one of the pseudospark hollow electrodes. This corona-plasma trigger can be used either at the cathode or anode side of the pseudospark, and it can be connected as well to the high voltage electrode as to the grounded one. With this trigger scheme, a pseudospark switch working at pulse repetition frequencies (PRF) up to 100 Hz has been demonstrated in a continuous mode of operation, while PRF as high as 1 kHz has been achieved in a burst mode. The cumulative number of pseudospark discharges triggered with this technique is already above 5 * 10(7), and this corona-plasma triggered pseudospark is still in operation without performance degradation. The main advantage of this pseudospark triggering technique lies in its simultaneous simplicity and reliability allowing high repetition rate, long lifetime, and the complete absence of keep-alive electrode and standby power consumption.Pages: 330-33

Triggered breakdown in low-pressure hollow cathode (pseudospark) discharges

Triggered breakdown in hollow cathode discharges in geometries similar to those used for pseudospark switches and pseudospark pulsed electron beams has been investigated experimentally and with a two-dimensional model previously developed. A systematic study of the influence of the discharge conditions (applied voltage and pressure), geometry, and trigger conditions (trigger intensity and position) on the time to breakdown in helium is presented, and some data are also shown for argon. Excellent qualitative agreement is found between the model predictions and the experimental results. The relation between the time to breakdown and the geometrical distribution of injected charge is discussed, and the understanding gained from these model results is used to suggest guidelines for trigger optimization. Conditions wherein significant oscillations in the currenta "current quenching'' effectare observed in the prebreakdown current wave form are discussed.Pages: 77-8