UPS systems and methods using dual mode rectifier/inverter

A system comprising:

• a UPS comprising an AC input, an AC output, a first converter circuit having a first port configured to be coupled to the AC input, a second converter circuit having a first port configured to be coupled to the AC output and a DC bus coupling second ports of the first and second converter circuits;
• a first switch configured to couple and decouple the AC input to and from the AC output of the UPS;
• a second switch configured to couple and decouple an AC source to and from the AC input of the UPS;
• and
• a control circuit configured to control the UPS, the first switch and the second switch responsive to a state of the AC source, wherein the control circuit is configured provide a first mode of operation wherein the first switch is open, the second switch is closed and the first and second converter circuits respectively operate as a rectifier and inverter coupled between the AC input and the AC output and a second mode of operation wherein the first switch is closed, the second switch is open and the first and second converter circuits operate as parallel inverters coupled between the DC bus and the AC output.

A UPS system comprising:

• a plurality of UPS module locations configured for installation of UPS modules;
• and
• at least one UPS module installed in at least one of the UPS module locations and comprising:
• an AC input;
• an AC output;
• a first converter circuit having a first port configured to be coupled to the AC input;
• a second converter circuit having a first port configured to be coupled to the AC output;
• a DC bus coupling second ports of the first and second converter circuits;
• and
• a first switch configured to couple and decouple the AC input to and from the AC output;
• a second switch having a first terminal coupled to the AC input;
• and
• a static switch configured to couple and decouple an AC source to and from a second terminal of the second switch of the at least one UPS module.