AC/DC converter circuit for common three-phase AC input voltages and method of operating such converter circuit

An AC/DC converter circuit for converting N>2 AC supply voltages into a DC voltage, the circuit comprising:

• N full bridge external converters, each of the N full bridge external converters comprising a first terminal configured to be connected to a separate one of the N>2 AC supply voltages and a second terminal, wherein the second terminals are coupled to each other;
• N intermediate converters, each of the N intermediate converters configured to receive an output of a different respective one of the N full bridge external converters at DC terminals of the intermediate converter;
• N transformers, each of the N transformers configured to receive an output of a different respective one of the N intermediate converters at a primary side of the transformer;
• N resonant circuits, each of the N resonant circuits disposed between a different respective one the N intermediate converters and a different respective one of the N transformers;
• and
• N internal rectifiers, each configured to be connected to a secondary side of a different respective one of said N transformers, wherein:
• each of the N internal rectifiers comprises first and second MOSFETs having source and drain terminals, the drain terminals of the N first MOSFETs are directly, electrically connected to a first node, the source terminals of the N second MOSFETs are directly, electrically connected to a second node, and a voltage potential developed between the first and second nodes constitutes the DC voltage, and
• for each of the N internal rectifiers, the source of the first MOSFET is directly, electrically connected to the drain of the second MOSFET and to the secondary side of a different respective one of said N transformers.