Dielectric strength of triggered vacuum switches with six-gap electrode system

Switching conditions influence on dielectric strength of internal insulation of high-current triggered vacuum switches with a trapezoidal rod electrode system is investigated. Investigations were carried out for two switching modes. In the first mode electrode erosion occurs mainly in a vapour phase when the electrode's surface remains smooth enough after switching. In the other switching mode, drop phase of electrodes erosion prevailed and considerable electrode surface damage took place. It follows from experimental data statistical processing that breakdown voltage distribution is described satisfactorily with the Weibull distribution law. The influence of gap and electrode material on dielectric strength of triggered vacuum switches is considered.