Dielectric strength of two series connected vacuum interrupters

Statistical dielectric strength tests of high-voltage vacuum interrupters and series connected vacuum interrupters have been conducted. It has been shown that the experimental distribution of the vacuum interrupter breakdown voltage can be described quite well with the two-parameter Weilbull distribution. The experimental breakdown voltage distribution of the series connected vacuum interrupters has been compared with the calculated distribution functions. The calculations were based on the earlier proposed mathematical model of the series connected vacuum gaps breakdown. Experimentally established functions of the breakdown voltage distribution in each gap are used in this model. Also, the dielectric strength characteristics of series connected vacuum interrupters with of the unequal voltage division between them have been studied.