Patent ID: 7830681

Claim:
A system comprising: a plurality of modular transformers each including a phase-shifted primary winding coupled to an input power source and a plurality of phase-shifted secondary windings each coupled to a power cell; a first phase output line having at least a first level power cell and a second level power cell, wherein a first one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell and a second plurality of the phase-shifted secondary windings coupled to the second level power cell; a second phase output line having at least a first level power cell and a second level power cell, wherein a second one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell and a second plurality of the phase-shifted secondary windings coupled to the second level power cell; and a third phase output line having at least a first level power cell and a second level power cell, wherein a third one of the modular transformers has a first plurality of the phase-shifted secondary windings coupled to the first level power cell, and a second plurality of the phase-shifted secondary windings coupled to the second level power cell.