Patent ID: 7362206

Claim:
A variable transformer having a variable effective turns ratio comprising a high frequency matrix transformer comprising a plurality of transformer modules, each of the plurality of transformer modules having a respective transformer module primary winding, the high frequency matrix transformer having a matrix transformer primary winding comprising all of respective transformer module primary windings connected in series, each one of the plurality of transformer modules having a respective secondary winding having at least a respective start termination and a respective end termination, each one of the plurality of transformer modules having, respectively, a respective full-wave rectifier connected to the at least a respective start termination and a respective end termination of the respective secondary winding of the respective each one of the plurality of transformer modules, each of the respective full-wave rectifiers having a respective output termination, all of respective output terminations of the respective full wave rectifiers being connected in parallel as an output of the variable transformer, at least one of the plurality of transformer modules having an ac switch connected between the at least a respective start termination and the respective end termination to short-circuit the respective secondary winding of at least one of the plurality of transformer modules, and a controller for tuning on and off the ac switch and for turning off and on the respective full wave rectifiers of the at least one of the plurality of transformer modules so as to vary the effective turns ratio of the variable transformer.