Improving the PRF of high pressure gas switches

Investigations into the repetitive operation of spark gaps has led to some degree of understanding of the nature of the recovery process and three distinct phases have been suggested: removal of charge carriers from the inter-electrode region, which takes a few tens of μs; recovery of the neutral gas density, which may take a few ms; and recovery of the ability of the switch to be overvolted above its DC breakdown level. The processes which govern this stage of recovery are unknown. In order to identify mechanisms which are responsible for recovery, two parallel experiments have been undertaken. The first involves the measurement of the neutral gas density after breakdown to determine its influence. The second is a double pulse experiment which probes the dielectric strength of the gas at various times after breakdown, to determine the voltage recovery rate