| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage adjustment device for correcting an unbalanced voltage due to the imbalance of a single-phase load or a single-phase distributed type power supply in a three-phase power system.SOLUTION: A voltage adjustment device of the present invention is provided with a secondary winding having a plurality of taps in a two-phase excitation transformer configured with Y-connection in a three-phase power system and a first and a second on-load tap changer for changing the plurality of taps from one to another. A series transformer is provided in a phase having no secondary winding or one other phase, and the secondary winding of the excitation transformer is connected to the secondary winding of these series transformers via the first and the second on-load tap changers. In response to the state of imbalance in a line voltage, an unbalanced voltage occurring on a load side of the three-phase power system is corrected by changing over the first and the second on-load tap changers. Further, taps of a tertiary winding for collectively adjusting three-phase voltages are connected to the series transformers installed in each phase via a third on-load tap changer, whereby the three-phase voltages are adjusted. |
