DEVICE FOR REGULATING AND BALANCING VOLTAGE IN THREE-PHASE LINE WITH NEUTRAL BROUGHT OUT Russian patent published in 1994 - IPC

FIELD: electrical engineering. SUBSTANCE: device has booster transformer whose primary windings are connected in opposing zigzag and to line phases and its secondary windings are connected in series at break of phase conductors. Line voltage is measured and in case of unbalance voltage deviation from rated value δu and reverse and zero sequence factors are determined. At δu>0 or δu<0 new values of are determined on condition that maximum or minimum of phase voltages decreases or, respectively, increases by minimum regulation step. If new values are lower than original ones, voltage across faulty phase is reduced or, respectively, increased, by regulating booster transformer. Besides, booster transformer windings and core are checked for condition. EFFECT: improved reliability of voltage regulation. 2 dwg