AC to DC power supply systems and methods

An AC to DC power supply system comprising:

• a three-phase transformer including a grid-connectable primary side with three windings and a secondary side;
• an active rectifier coupled to the primary side of the transformer, the active rectifier switchably connecting each of the three windings in series between a positive bus and a negative bus to alter a magnetic flux in a core of the transformer;
• a passive rectifier coupled to the secondary side of the transformer to rectify AC power to DC power at an output of the passive rectifier;
• and
• an isolating DC-to-DC converter coupled between the positive bus and the negative bus and the output of the passive rectifier, wherein the DC-to-DC converter is configured to feed power from the active rectifier to the output of the passive rectifier while galvanically isolating the active rectifier from the output of the passive rectifier.

A method for providing power to a load, the method comprising:

• coupling a transformer to a source of sinusoidal AC power and transforming voltage and current of the AC power with the transformer to produce transformed AC power on a secondary side of the transformer;
• switchably drawing power, simultaneously with the transforming, from each winding of the transformer to add a non-sinusoidal voltage to each primary winding of a primary side of the transformer, thereby inducing a non-sinusoidal voltage in the transformed AC power in each secondary winding of the secondary side of the transformer;
• rectifying the non-sinusoidal voltage in the transformed AC power to produce rectified DC power;
• applying the rectified DC power to a DC load;
• and
• feeding the drawn power from each primary winding to the DC load via a galvanically isolated coupling.