Effects of Preionization Assembly Structural Parameters on Triggering Performance of Multigap Gas Switch Gaps

Developing a gas switch with low jitter is crucial for the linear transformer driver (LTD) bricks and modules to be triggered in the proper sequence. Preionization is an effective approach to enhance the triggering performance of gas switches. This article focuses on a disk-shaped preionization assembly (DPA) and analyzes the impact of variations in the DPA structural parameters (gap spacing d and disk height h) as well as the trigger pulse polarity on the triggering characteristics of multigap gas switch gaps. To, respectively, investigate the influence of preionization on the different types of switch gaps, a two-gap gas switch (TGGS) consisting of one trigger gap and one self-breakdown gap is adopted. The trigger experiments for the separate preionization gap and the TGGS equipped with the DPA are conducted. The experimental results demonstrate that the breakdown delay of the preionization gap with large d exhibits the polarity effect. The polarity effect of the breakdown delay and jitter of the trigger and self-breakdown gaps are opposite. The changes of d and h have reversed influence on the breakdown properties of the two types of switch gaps. Because the self-breakdown gap has greater breakdown delay and jitter than the trigger gap, the overall performance of the TGGS is primarily determined by the former. Employing a DPA with larger h and moderate d and adopting a negative trigger pulse could reduce the trigger delay and jitter of the switch.