Patent ID: 8492928

Claim:
In an uninterruptible power supply (UPS) system, a front-end converter comprising: a boost circuit having first and second inputs; a positive output node, a negative output node, and a neutral output node; and first and second switches, the boost circuit including directional circuit components comprising first and second output diodes and first and second input diodes, with an anode of the first input diode and a cathode of the second input diode connected to the first input of the boost circuit and an anode of the second input diode connected to the second input of the boost circuit, wherein the directional circuit components are configured to rectify incoming alternating-current (AC) power to provide a positive voltage across a positive capacitor coupled between the positive output node and the neutral output node and to provide a negative voltage across a negative capacitor coupled between the negative output node and the neutral output node wherein the first and second inputs are each directly connected to at least one of the directional circuit components; and wherein an anode of the first output diode is connected to a cathode of the first input diode, a cathode of the second output diode is connected to the anode of the second input diode, the first switch is connected on one end between the first input diode and the first output diode and on another end to a neutral connection, and the second switch is connected on one end between the second output diode and the second input diode and on another end to the neutral connection; a single inductor coupled to the first input of the boost circuit; a first AC input and a neutral AC input together configured to receive alternating-current power; a battery having a negative port and a positive port; a first device coupled, disposed, and configured to selectively couple the single inductor to one of the first AC input or the positive port of the battery; a second device coupled, disposed, and configured to selectively couple the negative port of the battery to the second input of the boost circuit; a third device coupled to the anode of the first input diode and the cathode of the first input diode and configured to selectively bypass the first input diode; and a first controller coupled to the third device and configured to cause the third device to close to bypass the first input diode during an on-battery mode and to open during an online mode, wherein the single inductor is shared between the online mode of the converter and the on-battery mode of the converter and the battery is coupled through the single inductor to the first input of the boost circuit during the on-battery mode; and wherein the single inductor is an only inductor coupling the battery to the boost circuit.