The Method of Circuit Breaker Interrupting Capacity Verification Considering Breaking Sequences

In view of the problem that only considers the total current of the short circuit point instead of the probable maximum short circuit current in breaking capacity checking practice of current circuit breaker, the influence of the breaking sequence of side circuit breakers and branch circuit breakers on the short-circuit current through the circuit breaker is analyzed, a new idea for the selection of the circuit breaker interrupting capacity is provided. Taking Tianyi Substation as an example, the maximum short-circuit current in the branch of the circuit breaker and the total current of the short-circuit point were calculated. The case study shows that the breaking capacity of the circuit breaker should not be checked by the total current of the short circuit because it needs higher breaking capacity of circuit breaker.