In view of the technical difficulties in verifying the breaking short-circuit current in the generator circuit breaker selection of large units

the outlet short-circuit current of large generating unit is calculated. In the calculation

there is a problem that the generator circuit breaker(GCB) cannot break the asymmetrical short-circuit of the power system. According to the results of the electric arc resistance test

the influence of the separation time of the dynamic and static contacts and the electric arc resistance on the ability of breaking the short-circuit current by GCB and the arc extinguishing performance are analyzed

which provided the basis for the equipment selection.