Abstract: A variable leakage transformer or a variable voltage transformer comprising a magnetic core with a main magnetic path and a sub-magnetic path, the main magnetic path having at least a common magnetic path with the sub-magnetic path, a primary winding wound on said common magnetic path of the core, a secondary winding wound on said main magnetic path of the core, and means for controlling the magnetic flux in said sub-magnetic path. By controlling the magnetic flux in the sub-magnetic path, the leakage of the flux induced by the primary winding from the main magnetic path to the sub-magnetic path can be controlled, thus the coupling between the primary and secondary windings, and conduction period in each cycle of the AC output voltage are controlled. The control of the conduction period in each cycle provides the control of the power transmitted from the primary winding to the secondary winding.

Abstract: A variable leakage transformer having a closed main magnetic path and a closed submagnetic path having a leg common with said main magnetic path. A primary winding is wound on said common leg, and a secondary winding is wound on said main magnetic path. The magnetic flux in the common leg is controlled by other control windings which are connected to a control DC power source. The primary winding has two portions, and one of them is closely coupled magnetically with the secondary winding in order to improve the output waveform. By controlling the magnetic flux in the sub-magnetic path, the leakage of the flux induced by the primary winding from the main magnetic path to the sub-magnetic path can be controlled; thus the coupling between the primary and the secondary winding, and conduction period in each cycle of the AC output voltage are controlled. The control of the conduction period in each cycle provides control of the power transmitted from the primary winding to the secondary winding.

Abstract: A variable leakage transformer or a variable voltage transformer comprising a magnetic core with a main magnetic path and a sub-magnetic path, the main magnetic path having at least a common magnetic path with the sub-magnetic path, a primary winding wound on said common magnetic path of the core, a secondary winding wound on said main magnetic path of the core, and means for controlling the magnetic flux in said sub-magnetic path. By controlling the magnetic flux in the sub-magnetic path, the leakage of the flux induced by the primary winding from the main magnetic path to the sub-magnetic path can be controlled, thus the coupling between the primary and secondary windings, and conduction period in each cycle of the AC output voltage are controlled. The control of the conduction period in each cycle provides the control of the power transmitted from the primary winding to the secondary winding.