Dual boost converter for UPS system

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

• detecting a loss of input power from a primary power source;
• responsive to detecting the loss of the input power, generating, in a backup mode of operation, a negative DC output voltage using a backup power source through a first current path that includes a first diode coupled between the backup power source and a DC power bus;
• detecting a presence of the input power from the primary power source;
• and
• responsive to detecting the presence of the input power, generating, in a line mode of operation, the negative DC output voltage using the primary power source through a second current path that bypasses the first diode and includes a second diode coupled between the primary power source and the DC power bus.

A power converter, comprising:

• a first power input to receive AC input power;
• a second power input to receive backup power;
• a power output to provide output power derived from at least one of the AC input power and the backup power;
• a first diode and a second diode;
• and
• means for providing a negative DC output voltage to the power output through the first diode and the second diode using the backup power in a backup mode of operation, and providing the negative DC output voltage to the power output through the second diode using the AC input power in a line mode of operation.