FIELD: electricity.
SUBSTANCE: as the first surge of short circuit current (SC) appears, the time of its passage is measured, this time is compared with the time of delays for actuation of all SCB protections actuation installed in lines that stretch from the substation buses, they monitor availability of SC current in all phases and if the SC current flows in two phases, and the time of its passage is equal to the time of delay of the protection actuation in one of the SCB, they establish occurrence of the double-phase SC and the disconnecting SCB, from the moment of disconnection of the SC current they start counting time of delay of automatic re-closing (ARC) plus the time of delay of protection actuation with acceleration of the disconnected SCB, and they monitor the moment of the repeated SC current surge appearance, its availability in all phases, and the moment of its diversion, and if upon completion of ARC delay time the SC current appears, flows in three phases and disconnects at the moment of completion of protection actuation delay time with acceleration, then a conclusion is made on repeated connection of the SCB to SC and transition of the double-phase SC into three-phase one in case of unsuccessful ARC of this circuit breaker. The proposed method makes it possible to produce information on transition of the double-phase SC into three-phase with unsuccessful ARC of the SCB in the radial line.
EFFECT: expansion of functional capabilities by production of information on transition of a double-phase short circuit into a three-phase one under unsuccessful automatic reclosing of a sectioning circuit breaker of a radial line.
2 dwg
