FIELD: electricity.
SUBSTANCE: short circuit current is fixed at the input of feeding transformer and in outgoing lines; according to invention, short circuit current is simultaneously fixed at the input of feeding transformer and in outgoing lines; position of the switch of outgoing line in which short circuit occurred is controlled; voltage on section of buses of feeding transformer is controlled, and if short circuit current is present also at the input of feeding transformer, and in one of outgoing lines, and after it has been switched off with the protection, the switch of this line remained in switched on position; at that, there is no voltage on the section of buses of feeding transformer; there can be made the conclusion that short circuit occurred in outgoing line and its switch failed; in this case the automatic reclosure prohibition signal is supplied. In case of short circuit on buses of feeding transformer there simultaneously fixed is short circuit current at the input of feeding transformer and in outgoing lines; in case there is no short circuit current in outgoing lines, and in case there is short circuit current at the transformer input, there can be made the conclusion that short circuit occurred on buses of feeding transformer and the automatic reclosure prohibition signal is supplied. Thus, automatic reclosure prohibition signal is supplied only in case of short circuit on bus of double-transformer substation or in outgoing line in case of failure of its switch irrespective of short circuit kind (two- or three-phase).
EFFECT: improving the method accuracy by controlling short circuit current in outgoing lines, position of switches in outgoing line, current at the input of feeding transformer, availability of voltage at the input of feeding transformer, enlarging functional capabilities of the method, increasing life time of automatic reclosure switch, reducing the costs for its repair and service.
3 dwg
