DEVICE FOR VOLTAGE RECOVERY AND BALANCING AT CORE BREAK Russian patent published in 2015 - IPC H02J9/00 H02J9/06 H02M5/14 

FIELD: electricity.

SUBSTANCE: device comprises cable clamps A, B, C, three direct-current relays for phase control, each of them containing a power supply source consisting of a single-phase double-winding transformer, a single-phase bridge rectifier, a capacitive filter and direct-current magnet containing an in-series connected additional resistor and a winding placed at the magnet core, at that the above resistor is shunted by a capacitor, moreover each relay is equipped with one opening contact and closing contacts, which control thyristor keys with three phase recovering capacitors and three phase-shifting chokes, and three output clamps. Primary windings of the above transformers are coupled to linear voltage of the respective phases while secondary windings are connected to diagonal lines of own rectifiers. Positive outputs of the rectifiers are connected to positive outputs of the capacitive filters, shunt capacitor and additional resistor while negative outputs are connected to negative outputs of the capacitive filters and free ends of the magnet windings. The thyristor keys with the phase recovering capacitors are connected in parallel to the above transformers while the thyristor keys with the phase shifting capacitors are connected in series between the cable clamps and the respective output clamps. All the thyristor keys are identical and each of them contains three parallel circuits: the first and the third circuit are formed with thyristors of direct and reverse connection, and the second circuit is formed with an in-series connected diode of direct connection, a contact group, a resistor and a diode of reverse connection; at that the contact group of the thyristor keys includes an in-series connected closing contact of a lagging phase and an opening contact of the respective phase, the contact group of the second circuit of shunting thyristor keys is formed with the closing contact of the lagging phase.

EFFECT: potential setting of the required time for voltage recovery.

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