DC UPS architecture and solution

A method of supplying DC power to a load, the method comprising:

• receiving, by a first winding of a transformer in a first mode of operation, AC power from an AC power source;
• providing, by at least one second winding of a plurality of second windings of the transformer in the first mode of operation, a first portion of DC power derived from the AC power to at least one respective battery of a plurality of batteries coupled to the transformer;
• providing, by a third winding of the transformer in the first mode of operation, a second portion of the DC power derived from the AC power to an output;
• receiving, by one or more second windings of the plurality of second windings of the transformer in a second mode of operation, DC power from one or more respective batteries at least one battery of the plurality of batteries;
• and
• providing, by the third winding of the transformer in the second mode of operation, output power derived from the DC power to the output.

A DC power supply, the power supply comprising:

• a first input configured to be coupled to an AC power source;
• a plurality of second inputs, each second input being configured to be coupled to a respective battery of a plurality of batteries;
• an output;
• and
• means for providing, in a first mode of operation, a first winding of a transformer to generate, based on AC power received from the AC power source, a first voltage across each winding of a plurality of second windings of the transformer to charge at least one battery of the plurality of batteries, and a second voltage across a third winding of the transformer, and for controlling, in a second mode of operation, the plurality of second windings to generate, based on power received from the plurality of batteries, a third voltage across the third winding.