A new controlled constant-voltage transformer

A constant-voltage power device is developed which, while similar to the well-known ferroresonant regulator, overcomes many of its limitations. The new controlled constant-voltage transformer employs switching devices and a dc electrolytic capacitor rather than the saturating core and ac capacitor of the ferroresonant regulator. Since the output is controllable, a dc feedback loop may be used to remove the effects of frequency changes, varying loads, etc.