FIELD: electricity.
SUBSTANCE: invention is related to automatic equipment of electric mains and intended for control of a double-phase short-circuit and inhibition of the second cycle of automatic reclosing for the master circuit-breaker (MCB) in the line feeding the transformer substation. The technical result includes expansion of functionality by receipt of data on the double-phase short-circuit and inhibition of the second cycle of automatic reclosing for the MCB in the line. According to the invention since loss of the linear voltage at the transformer the first countdown is started, which is equal to the operation delay time of the in-line MCB protection, at that loss of two other linear voltages is controlled and when they are lost at the first countdown completion then the conclusion is made about cut-off of the MCB and since its cut-off moment the second countdown is started equal to the operation delay time of the first cycle of the MCB automatic reclosing, at that the linear voltage is controlled and when the two linear voltages appear when the second countdown is over and the first linear voltage does not appear then the conclusion is made about the second automatic reclosing in result of short-circuiting and since the moment of its actuation the third countdown is started, which is equal to the operation delay time the in-line MCB protection with acceleration, at that loss of two appeared voltages is controlled and when they are lost at the moment of the third countdown completion the conclusion is made about automatic reclosing of the MCB and a signal is sent to inhibit the second cycle of the MCB automatic reclosing in the line feeding the transformer substation.
EFFECT: while using the claimed method the data can be obtained on double-phase short-circuiting and inhibition of the second cycle of automatic reclosing for the MCB in the line feeding the transformer substation.
2 dwg
