Multiple energy storage device controller

• US 6,639,383 B2
• Filed: 07/19/2002
• Issued: 10/28/2003
• Est. Priority Date: 04/19/2001
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: American Power Conversion Corporation (Schneider Electric SE)
• Inventors: Hoff, C. Michael, Cohen, Daniel C., Nelson, James E., Hopkins, Philip C.
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US10/199,472
• Publication Number:
  US 20030052644A1
• Time in Patent Office: 466 Days
• Field of Search: 320/116, 320/118, 320/119, 320/121, 320/122, 320/127, 320/128, 320/135, 320/137
• US Class Current: 320/116
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems

Abstract

A system for controlling multiple energy storage devices in an uninterruptible power supply (UPS) system is provided. In one embodiment of the invention, the system generally includes a charger coupled to a direct current (DC) bus of the UPS system, and two or more energy storage circuits, each of which includes a power regulator coupled to the charger and coupled to the DC bus, at least one energy storage device coupled to the power regulator, and a processor coupled to the power regulator for controlling the charge and discharge of the at least one energy storage device. In another embodiment of the invention, digital communication between two or more controllers is accomplished over the DC bus through use of the Control Area Network (CAN) protocol.

Claims

1. An uninterruptible power supply system comprising:

an input for receiving power;

an output for providing power;

a direct current (DC) line coupled to the input;

an output circuit coupled to the DC line and the output;

a plurality of DC power sources coupled to the DC line;

a power controller coupled to at least a first DC power source of the DC power sources and configured to control at least one of amounts of charge power transferred from the DC line to the first DC power source and amounts of discharge power transferred from the first DC power source to the DC line.

2. The system of claim 1 wherein the power controller comprises a first power regulator and a first processor, the first power regulator being coupled between the DC line and the first DC power source and the first processor being coupled to the first power regulator.

3. The system of claim 2 wherein the power controller further comprises a second power regulator coupled between the DC line and the a second DC power source of the plurality of DC power sources.

4. The system of claim 3 wherein the power controller further includes a second processor coupled and configured to communicate with the first processor.

5. The system of claim 4 wherein the first processor and the second processor are capable of communication with each other via the DC line.

6. The system of claim 1 wherein the power controller is configured to control at least one of amounts of charge power transferred from the DC line to a second DC power source of the plurality of DC power sources and amounts of discharge power transferred from the second DC power source to the DC line, and wherein the power controller includes a central controller.

7. The system of claim 6 wherein the central controller is configured to cause the first DC power source to be charged faster than the second DC power source if the second DC power source has a higher capacity value than the first DC power source.

8. The system of claim 6 wherein the central controller is configured to cause the first DC power source to be discharged faster than the second DC power source if the second DC power source has a lower capacity value than the first DC power source.

9. An uninterruptible power supply (UPS) system comprising:

an input for receiving power;

an output for providing power;

a direct current (DC) line coupled to the input;

an output circuit coupled to the DC line and the output;

a plurality of DC power sources coupled to the DC line;

a plurality of power controllers coupled to the DC power sources and configured to control at least one of amounts of charge power transferred from the DC line to the DC power sources and amounts of discharge power transferred from the DC power sources to the DC line.

10. The system of claim 9 further comprising a plurality of separate modules, each module containing a power controller of the plurality of power controllers and a DC power source of the plurality of DC power sources.

11. The system of claim 10 wherein each power controller comprises a power regulator and a processor, the power regulator being coupled between the DC line and the respective DC power source and the processor being coupled to the power regulator.

12. The system of claim 11 wherein the processors are configured to communicate with each other via at least one of the DC line, a fiber-optic medium, wiring, and a wireless link.

13. The system of claim 12 further comprising a master power controller coupled to the plurality of power controllers and configured to control rates of charging and discharging of the DC power sources.

14. The system of claim 13 wherein the master power controller is configured to control a voltage on the DC line to be in one of a first range indicating that at least one of the DC power sources is charging, a second range indicating that at least one of the DC power sources is discharging, a third range indicating that the DC power sources are neither charging nor discharging, and a fourth range indicating availability of greater than capacity power.

15. The system of claim 12 wherein the master power controller is configured to cause a first DC power source from the plurality of DC power sources to be charged faster than a second DC power source of the plurality of DC power sources if the second DC power source has a higher capacity value than the first DC power source, and to cause the first DC power source to be discharged faster than the second DC power source if the second DC power source has a lower capacity value than the first DC power source.

16. The system of claim 11 wherein the processors are configured to communicate with each other using the Control Area Network protocol.

17. A method of operating an uninterruptible power supply system, the method comprising:

providing input power from an input stage coupled to an AC power source;

processing the input power in an output stage to provide an output power to an output;

controlling at least one of amounts of the input power provided to a first DC power source from a plurality of DC power sources for charging the firs tDC power source and amounts of DC power provided by the first DC power source to the output stage.

18. The method of claim 17 wherein the controlling is also performed for a second DC power source from the plurality of DC power sources to cause capacities of the first and second DC power sources to be substantially equal.

19. The method of claim 17 wherein the controlling controls power flow to charge the first DC power source faster than the second DC power source if the second DC power source has a higher capacity value than the first DC power source, and to discharge the first DC power source faster than the second DC power source if the second DC power source has a lower capacity value than the first DC power source.

20. The method of claim 19 wherein the controlling causes a voltage at an input to the output stage to be in one of a first range indicating that at least one of the DC power sources is charging, a second range indicating that at least one of the DC power sources is discharging, a third range indicating that the DC power sources are neither charging nor discharging, and a fourth range indicating availability of greater than capacity power.

21. The method of claim 19 further comprising monitoring status of the plurality of DC power sources and the controlling is performed based on information monitored from at least one of the DC power sources.