UPS systems and methods using dual mode rectifier/inverter

Patent metadata

Field	Value
Publication number	US-9806561-B2
Application number	US-201313935533-A
Country	US
Kind code	B2
Filing date	Jul 4, 2013
Priority date	Jul 4, 2013
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

An uninterruptible power supply (UPS system) includes a first converter circuit, a second converter circuit and a DC bus coupled to the first and second converter circuits. The system further includes a control circuit configured to control the first and second converter circuits and to selectively couple the first and second converter circuits to an AC source and a load to provide a first mode of operation wherein the first and second converter circuits respectively operate as a rectifier and an inverter to serve the load from the AC source and a second mode of operation wherein the first and second converter circuits operate as parallel inverters to serve the load from the DC bus. The control circuit may be configured to couple the AC source to the load to bypass the first and second converter circuits in a third mode of operation.

First claim

That which is claimed:

1. An uninterruptible power supply (UPS) system comprising:
a plurality of UPS module locations; and
a UPS module installed in one of the UPS module locations and comprising:
a first converter circuit;
a second converter circuit;
a DC bus that couples the first and second converter circuits to one another; and
a control circuit configured to control the first and second converter circuits and to selectively couple the first and second converter circuits to an AC source and a load to provide a first mode of operation wherein the first and second converter circuits respectively operate as a rectifier and an inverter to serve the load from the AC source and a second mode of operation wherein the first and second converter circuits operate as parallel inverters to serve the load from the DC bus that couples the first and second converter circuits to one another, wherein the control circuit comprises:
a first switch configured to couple and decouple a first port of the first converter circuit to and from the AC source; and
a second switch configured to couple and decouple the first port of the first converter circuit to and from the load.

2. The system of claim 1 , wherein the control circuit is configured to couple the AC source to the load to bypass the first and second converter circuits in a third mode of operation.

3. The system of claim 2 , wherein the control circuit transitions between the first and third modes based on a voltage of the AC source.

4. The system of claim 3 , wherein the control circuit transitions to the first mode responsive to the voltage of the AC source deviating outside of a predetermined range.

5. The system of claim 4 , wherein the control circuit maintains a voltage at the load within the predetermined range when operating in the first mode.

6. The system of claim 4 , wherein the control circuit prioritizes conversion efficiency over maintenance of a nominal voltage at the load when operating in the first mode.

7. The system of claim 1 , wherein the control circuit is configured to close the first switch and open the second switch to support the first mode of operation and wherein the control circuit is configured to open the first switch and close the second switch to support the second mode of operation.

8. The system of claim 7 , wherein the control circuit is configured to close the first and second switches to support a third mode of operation in which the AC source is coupled to the load via the first and second switches.

9. The system of claim 1 , further comprising a static switch configured to couple and decouple the AC source to and from the first switch.

10. 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.

11. The system of claim 10 , wherein the control circuit is configured to close the first switch to bypass the first and second converter circuits in a third mode of operation.

12. The system of claim 11 , wherein the control circuit is configured to transition between the first and third modes based on a voltage of the AC source.

13. The system of claim 11 , wherein the control circuit prioritizes conversion efficiency over voltage regulation when operating in the first mode.

14. 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.

15. The system of claim 14 , wherein the at least one UPS module is configured provide a first mode of operation wherein 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 and second converter circuits operate as parallel inverters coupled between the DC bus and the AC output.

16. The system of claim 15 , wherein the at least one UPS module is configured to close the first switch to bypass the first and second converter circuits in a third mode of operation.

17. The system of claim 16 , wherein the at least one UPS module transitions between the first and third modes based on a voltage of the AC source.

18. The system of claim 16 , wherein the at least one UPS module prioritizes conversion efficiency over voltage regulation when operating in the first mode.

19. The system of claim 14 , wherein the at least one UPS module further comprises a third switch configured to couple and decouple the first port of the second converter circuit to and from the AC output.

Assignees

• Eaton Corp

Inventors

• Navarro George Arthur

Classifications

• H02J9/061 Primary

  for DC powered loads · CPC title

• H02J9/00

  Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting · CPC title

• H02J9/04

  in which the distribution system is disconnected from the normal source and connected to a standby source · CPC title

• Y02P80/11

  Cross-Sectional Technologies · mapped topic

• Y10T307/615

  Cross-Sectional Technologies · mapped topic