Breakdown properties on gas rail gap switch with operating voltage of ±100kV

Breakdown properties of a gas rail gap switch are presented in this paper. The switch is a three electrode, field-distortion-triggered design and incorporated with the low inductance capacitors. The influence of trigger pulse, working voltage, and gas species (N₂, and mixed gas of SF₆/Ar) on breakdown characteristics is demonstrated through experiments. The experimental results demonstrate that the self-breakdown voltage is proportional to the gas pressure for SF₆/Ar as well as N₂ and the triggering performance is much better with wider working voltage range, shorter breakdown delay and smaller jitter for SF₆/Ar compared with N₂. The reason of the gas species effect is explained by the electron collision ionization coefficient alpha. With different breakdown modes of the triggered gas gap taken into consideration, it is possible to interpret the phenomenon of the orderly variation of the triggered breakdown delay and jitter according to the charging voltage, as well as other novel phenomenon.