Ferroresonant three-phase constant AC voltage transformer arrangement with compensation for unbalanced loads

Claim 2

A ferroresonant three-phase constant AC voltage transformer comprising: three magnetically permeable transformer cores, a primary side winding and a secondary side winding formed on each of said transformer cores, three input terminals, three input means each of which can be in an inductive coupling and each of which provides an inductive reactance effectively in series with a corresponding one of said primary side windings to thereby form three primary phase winding units each in a predetermined connection pattern to the three input terminals, automatic voltage regulating means for controlling secondary side output voltages generated at the secondary side windings to a predetermined value, three compensating windings each formed so as to be inductively coupled with a corresponding one of said input means, and means for connecting said compensating windings to each other in series to form a series closed loop circuit.

Claim 3

The ferroresonant three-phase constant AC voltage transformer according to claim 1 wherein each said input means is realized with a reactor, and a turn ratio of a number of turns of a reactor to that of its corresponding compensating winding is substantially equal to such turn ratios for the other reactors and corresponding compensating windings.

Claim 4

The ferroresonant three-phase constant AC voltage transformer according to claim 1 wherein each said input means is realized by a magnetic shunt fixed on the corresponding transformer core with the corresponding compensating winding formed on that said magnetic shunt.

Claim 5

The ferroresonant three-phase constant AC voltage transformer comprising: three magnetically permeable transformer cores, first and second primary side windings and a secondary side winding formed on each of the transformer cores, two sets of three input terminals; six input means each of which can be in an inductive coupling and each of which provides an inductive reactance effectively in series with a corresponding one of said primary side windings to thereby form two sets of three primary phase winding units each, and with each such set in a predetermined connection pattern to a corresponding one of the two sets of three input terminals, automatic voltage regulating means for controlling secondary side output voltages generated at the secondary side windings to a predetermined value, six compensating windings each formed so as to be inductively coupled with a corresponding one of said input means, and means for connecting those said compensating windings corresponding to one of said two sets of primary phase winding units to each other in series to form a closed loop circuit, and means for connecting those said compensating windings corresponding to the other of said two sets of primary phase winding units to each other in series to form another closed loop circuit.

Claim 6

The ferroresonant three-phase constant AC voltage transformer comprising: three magnetically permeable transformer cores, first and second primary side windings and a secondary side winding formed on each of the transformer cores, two sets of three input terminals; six input means each of which can be in an inductive coupling and each of which provides an inductive reactance effectively in series with a corresponding one of said primary side windings to thereby form two sets of three primary phase winding units each, and with each such set in a predetermined connection pattern to a corresponding one of the two sets of three input terminals, automatic voltage regulating means for controlling secondary side output voltages generated at the secondary side windings to a predetermined value, six compensating windings each formed so as to be inductively coupled with a corresponding one of said input means, and means for connecting those said compensating windings corresponding to one of said two sets of primary phase winding units to each other in series to form a closed loop circuit, and means for connecting those said compensating windings corresponding to the other of said two sets of primary phase winding units to each other in series to form another closed loop circuit.

Claim 7

The ferroresonant three-phase constant AC voltage transformer according to claim 4 wherein each said input means is realized with a reactor, and a turn ratio of a number of turns of a reactor to that of its corresponding compensating winding is substantially equal to such turn ratios for the other reactors and corresponding compensating windings.

Claim 8

The ferroresonant three-phase constant AC voltage transformer according to claim 4 wherein each said input means is realized by a magnetic shunt fixed on the corresponding transformer core with the corresponding compensating winding formed on that said magnetic shunt.