The evaluation of restriking voltages

Considerable prominence has been given in recent Institution papers to the effects of restriking voltages on the performance of circuit breakers, but little guidance has been given to the general determination of these voltages. This paper deals with the approximate evaluation of restriking voltages by the use of equivalent circuits for transformers, generators, etc., and their combination and reduction to a number of standard circuits, the solutions for which are tabulated. The mathematical work involved in any given case has been reduced to routine evaluations. In particular, consideration has been confined to the interruption of 3-phase faults, but the principles can be applied to other types of faults, although these will not give higher voltages.