AC AND DC UNINTERRUPTIBLE ONLINE POWER SUPPLIES

• US 20090256422A1
• Filed: 02/18/2009
• Published: 10/15/2009
• Est. Priority Date: 04/11/2008
• Status: Active Grant

• Current Assignee: Vertiv Corporation (Vertiv Holdings Co.)
• Original Assignee: Liebert Corporation (Vertiv Holdings Co.)
• Inventors: Shelter, Russell E. JR., Taylor, Paul, Panfil, Peter A., Fox, Bret P.
• Granted Patent: US 8,203,235 B2
• Time in Patent Office: Days
• US Class Current: 307/23
• CPC Class Codes: H02J 9/062 for AC powered loads

Abstract

A power supply includes a rectifier that converts an alternating current input voltage to a first direct current voltage. An inverter that converts the first direct current voltage to an alternating current output voltage. A first set of output terminals that receives the alternating current output voltage. A second set of output terminals that receives the first direct current voltage. A charging circuit that charges a backup power source based on the first direct current voltage. The rectifier receives a second direct current voltage from the backup power source based on the power supply operating in a predetermined condition.

Claims

1. A power supply comprising:

a rectifier that converts an alternating current input voltage to a first direct current voltage;

an inverter that converts the first direct current voltage to an alternating current output voltage;

a first set of output terminals that receives the alternating current output voltage; and

a second set of output terminals that receives the first direct current voltage;

wherein the rectifier receives a second direct current voltage from a backup power source based on the power supply operating in a predetermined condition.

2. The power supply of claim 1 wherein the first set of output terminals supplies a first load with the alternating current output voltage, and

wherein the second set of output terminals supplies a second load with the first direct current output voltage.

3. The power supply of claim 1 wherein the rectifier receives the second direct current voltage when amplitude of the alternating current input voltage is less than a predetermined amplitude.

4. The power supply of claim 1 wherein the rectifier receives the second direct current voltage instead of the alternating current input voltage.

5. The power supply of claim 1 wherein the rectifier receives the second direct current voltage when amplitude of the alternating current input voltage is greater than a predetermined amplitude.

6. The power supply of claim 1 further comprising a direct current bus that is connected between the rectifier and the inverter,

wherein the second set of output terminals is connected to the direct current bus.

7. The power supply of claim 6 further comprising an interrupter that is connected to the second set of output terminals and limits current to a direct current load.

8. The power supply of claim 1 further comprising a bypass circuit that is connected between inputs of the rectifier and outputs of the inverter and that couples the alternating current input voltage to the first set of output terminals when in a bypass condition.

9. The power supply of claim 8 wherein the first set of output terminals receives the alternating current output voltage from the inverter when the bypass switch is in the bypass condition coupling the alternating current input voltage to the first set of output terminals.

10. The power supply of claim 8 further comprising a switch that prevents the alternating current input voltage from being received by the rectifier when the bypass circuit is in the bypass condition coupling the alternating current input voltage to the first set of output terminals.

11. The power supply of claim 1 wherein the rectifier limits current supplied to the inverter.

12. The power supply of claim 1 wherein the rectifier limits current supplied to the second set of output terminals.

13. The power supply of claim 1 wherein the inverter limits current supplied to the first set of output terminals.

14. The power supply of claim 1 further comprising a control module that monitors at least one of voltage, current and power of the first set of output terminals and the second set of output terminals,

wherein the control module signals the rectifier to limit current output of the rectifier based on the at least one of voltage, current and power of the first set of output terminals and the second set of output terminals.

15. The power supply of claim 1 further comprising a control module that monitors at least one of voltage, current and power of the first set of output terminals and the second set of output terminals,

wherein the control module signals the inverter to limit current output of the inverter based on the at least one of voltage, current and power of the first set of output terminals and the second set of output terminals.

16. The power supply of claim 1 wherein the rectifier is controlled to permit current to the second set of output terminals to increase when current to the first set of output terminals is less than a predetermined limit.

17. The power supply of claim 1 wherein at least one of the rectifier and the inverter are controlled to limit current to the first set of output terminals when current supplied to the first set of output terminals is greater than or equal to a predetermined limit.

18. The power supply of claim 1 wherein at least one of the rectifier and the inverter are controlled to permit current to the first set of terminals to increase when current supplied to the second set of terminals is less than a predetermined limit.

19. The power supply of claim 1 wherein the rectifier is controlled to limit current to the second set of terminals when current supplied to the second set of terminals is greater than or equal to a predetermined limit.

20. The power supply of claim 1 wherein at least one of the rectifier and the inverter are controlled to limit current to the first set of output terminals and the rectifier is controlled to limit current to the second set of output terminals when a sum of current supplied to the first set of output terminals and current supplied to the second set of output terminals is greater than a predetermined limit.

21. The power supply of claim 1 further comprising:

a first relay connected to the first set of output terminals;

a second relay connected to the second set of output terminals; and

a control module that selectively controls the first relay and the second relay to selectively provide current to at least one of the first set of output terminals and the second set of output terminals.

22. The power supply of claim 1 wherein the rectifier converts the alternating current input voltage to the first direct current voltage while converting the second direct current voltage to the first direct current voltage.

23. The power supply of claim 1 further comprising a charging circuit that charges the backup power source based on the first direct current voltage.

24. A method of operating a power supply comprising:

converting an alternating current input voltage to a first direct current voltage;

converting the first direct current voltage to an alternating current output voltage;

receiving the alternating current output voltage by a first set of output terminals;

receiving the first direct current voltage by a second set of output terminals; and

supplying a second direct current voltage from a backup power source to a rectifier based on the power supply operating in a predetermined condition.

25. The method of claim 24 further comprising:

supplying a first load with the alternating current output voltage; and

supplying a second load with the first direct current output voltage.

26. The method of claim 24 wherein the rectifier is supplied with the second direct current voltage when amplitude of the alternating current input voltage is less than a predetermined amplitude.

27. The method of claim 24 wherein the rectifier is supplied with the second direct current voltage instead of the alternating current input voltage.

28. The method of claim 24 wherein the rectifier is supplied with the second direct current voltage when amplitude of the alternating current input voltage is greater than a predetermined amplitude.

29. The method of claim 24 further comprising bypassing the rectifier and an inverter to supply the first set of output terminals with the alternating current input voltage.

30. The method of claim 29 further comprising preventing alternating current from being received by the rectifier when the first set of output terminals is supplied with the alternating current input voltage.

31. The method of claim 24 further comprising limiting current supplied to an inverter that converts the first direct current voltage to the alternating current output voltage.

32. The method of claim 24 further comprising limiting current supplied to the second set of output terminals.

33. The method of claim 24 further comprising limiting current supplied to the first set of output terminals.

34. The method of claim 24 further comprising:

monitoring at least one of voltage, current and power of the first set of output terminals and the second set of output terminals; and

signaling the rectifier to limit current output of the rectifier based on the at least one of voltage, current and power of the first set of output terminals and the second set of output terminals.

35. The method of claim 24 further comprising:

monitoring at least one of voltage, current and power of the first set of output terminals and the second set of output terminals; and

limiting current output of an inverter that converts the first direct current voltage to the alternating current output voltage based on the at least one of voltage, current and power of the first set of output terminals and the second set of output terminals.

36. The method of claim 24 further comprising permitting current to the second set of output terminals to increase when current to the first set of output terminals is less than a predetermined limit.

37. The method of claim 24 further comprising limiting current to the first set of output terminals when current supplied to the first set of output terminals is greater than or equal to a predetermined limit.

38. The method of claim 24 further comprising permitting current to the first set of terminals to increase when current supplied to the second set of terminals is less than a predetermined limit.

39. The method of claim 24 further comprising limiting current to the second set of terminals when current supplied to the second set of terminals is greater than or equal to a predetermined limit.

40. The method of claim 24 further comprising limiting current to the first set of output terminals and limiting current to the second set of output terminals when a sum of current supplied to the first set of output terminals and current supplied to the second set of output terminals is greater than a predetermined limit.

41. The method of claim 24 further comprising charging the backup power source based on the first direct current voltage.