Study on Inherent Dielectric Recovery Characteristics of Laser Triggered Vacuum Switch

As a promising pulsed power switch, the interruption performances of laser triggered vacuum switch (LTVS) is affected by the ablation of electrode and target, which is different from the traditional vacuum switch. To further improve the repetition frequency and breaking ability at high frequency of LTVS, the free dielectric recovery strength of LTVS is measured, that is, the dielectric recovery process without recovery voltage. Based on the detachable vacuum interrupter, the experimental platform of LTVS free dielectric recovery characteristics is built. By changing the current amplitude, frequency and electrode spacing, the curves of LTVS dielectric strength with time under different factors are compared, and the influence of various factors on free dielectric recovery strength of LTVS is discussed. The tested results show that the dielectric recovery strength of LTVS decreases with the increase of current amplitude and electrode spacing. With the change of frequency, the dielectric recovery strength at higher frequency is lower than that at lower frequency in the initial period of time, but then the dielectric strength recovers rapidly. All the above studies provide references for improving the repetitive interruption performances of LTVS.