X-ray triggered switching in SF/sub 6/ insulated spark gaps

Abstract

Several methods are being investigated for triggering low-jitter pressurized, SF/sub 6/-insulated spark gaps operating at 3 MV with the capability of switching hundreds of kiloamperes. One method, which is located external to the main current carrying plasma channel, uses pulsed x-rays to generate ionization within the working gas volume to initiate low jitter gas breakdown. In this paper, a model of gas breakdown with x-ray ionization is developed and results of two series of experiments are described. One experiment used 35 kV with a 1.83 mm gap and the other used 1 MV with a 7.62 cm gap. Both experiments used a 600 kV Febetron 706 flash x-ray source to demonstrate the feasibility of using pulsed x-rays as a means of triggering SF/sub 6/ insulated gaps with nanosecond jitter