FIELD: electricity.
SUBSTANCE: invention is intended to control successful and unsuccessful automatic reclosure of circuit breakers and determining type of short circuit in the sectionalised line of ring network supplied by different buses of the two-transformer substation. Since the moment of fault current surge at the substation busses the countdown time is started as a period equal to delay in actuation of each circuit breaker installed in the sectionalised line; at that availability of fault current and moment of its disappearance is monitored in all line phases and if fault current disappears at the moment of the above delay time ending and if it passed through two phases then the tripped circuit breaker is set for two double-phase fault, and if it passed through three phases then tripped circuit breaker is set for two three-phase fault; since the moment of fault current surge the second countdown time is started as a period equal to automatic reclosure of the tripped circuit breaker, at that occurrence of the second current surge is monitored, and if it appears at the moment of the second delay time ending with a value bigger than the rated operating current and less then fault current and fault current passed through two phases then successful automatic reclosure of the tripped circuit breaker upon self-cleared double-phase fault is stated or successful automatic reclosure of the tripped circuit breaker upon self-cleared three-phase fault is state if fault current passed through three phases; and if at the moment of the delay time ending for the tripped circuit breaker the second surge of fault current occurs and fault current passes through two phases and upon delay time with acceleration it trips then conclusion is made about unsuccessful automatic reclosure of the tripped circuit breaker at double-phase fault or if fault current appears and passes through three phases and the circuit breaker trips upon delay time with acceleration then conclusion is made about unsuccessful automatic reclosure of the tripped circuit breaker at three-phase fault.
EFFECT: expanding functionality by receipt of information about successful and unsuccessful automatic reclosure of circuit breaker with determination of fault type in the sectionalised line of ring network.
9 dwg
