Diagnosis of multi-gap gas switch with optical fiber detectors

A set of fiber detector which consists of an optical fiber array detector and a solar-blind plug-in optical sensor was developed for multi-gap gas switch optical diagnosis. The detailed discharging process was monitored using the detector and the influence of trigger voltage, gas pressure and UV pre-ionizing on the performance of the switch was also analyzed. The timing precision of the fiber array detector is better than 0.6 ns, and its time response is 3.2 ns. The solar-blind sensor responds to light whose wavelength lies between 260 nm and 320 nm. The following results were obtained by the diagnostic system: the order of the gaps breakdown is 3rd-2nd-1st-4th-5th-6th, and statistic delay and over-voltage breakdown delay take the majority of the whole time delay. The jitter of the switch can be reduced by raising the trigger voltage, lowering the gas voltage and stabilizing the intensity of the ultraviolet light.