Low voltage ride through for wind turbine generators

• US 20040145188A1
• Filed: 01/24/2003
• Published: 07/29/2004
• Est. Priority Date: 01/24/2003
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Hoffmann, Till, Luetze, Henning, Buecker, Andreas, Hagedorn, Ralf, Janssen, Wilhelm
• Granted Patent: US 6,921,985 B2
• Time in Patent Office: Days
• US Class Current: 290/44
• CPC Class Codes: F03D 7/0224 Adjusting blade pitch
• CPC Class Codes: F03D 7/0284 in relation to the state of the electric grid
• CPC Class Codes: F05B 2270/10711 applying a low voltage ride through method
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/40 Synchronising a generator for connection to a network or to another generator
• CPC Class Codes: H02J 9/00 Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
• CPC Class Codes: H02P 2101/15 for wind-driven turbines
• CPC Class Codes: H02P 9/007 Control circuits for doubly fed generators
• CPC Class Codes: H02P 9/10 Control effected upon generator excitation circuit to reduce harmful effects of overloads or transients, e.g. sudden application of load, sudden removal of load, sudden change of load
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

A wind turbine. The wind turbine includes a blade pitch control system to vary a pitch of one or more blades and a turbine controller coupled with the blade pitch control system. A first power source is coupled with the turbine controller and with the blade pitch control system to provide power during a first mode of operation. Uninterruptible power supplies coupled to the turbine controller and with the blade pitch control system to provide power during a second mode of operation. The turbine controller detects a transition from the first mode of operation to the second mode of operation and causes the blade pitch control system to vary the pitch of the one or more blades in response to the transition.

Claims

1. A wind turbine generator comprising:

a blade pitch control system to vary a pitch of one or more blades;

a turbine controller coupled with the blade pitch control system;

a first power source coupled with the turbine controller and with the blade pitch control system to provide power during a first mode of operation; and

an uninterruptible power supply coupled to the turbine controller and with the blade pitch control system to provide power during a low voltage event;

wherein the turbine controller causes the blade pitch control system to vary the pitch of the one or more blades in response to the transition in response to detection of a transition from the first mode of operation.

2. The wind turbine generator of claim 1 wherein a low voltage event comprises a generator output voltage of less than 75% of a rated voltage for the generator.

3. The wind turbine generator of claim 2 wherein the low voltage event occurs for up to 3 seconds.

4. The wind turbine generator of claim 1 wherein a low voltage event comprises a generator output voltage of less than 50% of a rated voltage for the generator.

5. The wind turbine generator of claim 4 wherein the low voltage event occurs for up to 3 seconds.

6. The wind turbine generator of claim 1 wherein a low voltage event comprises a generator between 15% and 50% of a rated voltage for the generator.

7. The wind turbine generator of claim 6 wherein the low voltage event occurs for up to 3 seconds.

8. The wind turbine generator of claim 1 wherein the first power source comprises a generator.

9. The wind turbine generator of claim 8 further comprising a power converter coupled to a generator, the power converter comprising:

an inverter coupled to receive power from the generator;

a converter controller coupled with the inverter to monitor a current flow in the inverter;

a circuit coupled with the input of the inverter and with the converter controller, the circuit to shunt current from the inverter in response to a control signal from the converter controller.

10. The wind turbine generator of claim 9 wherein the circuit comprises a crowbar circuit.

11. The wind turbine generator of claim 9 wherein the converter controller is coupled to the first power source to receive power during the first mode of operation and to the uninterruptible power supply to receive power during the low voltage event.

12. The wind turbine generator of claim 1 wherein the uninterruptible power supply comprises a battery power supply.

13. The wind turbine generator of claim 1 wherein the uninterruptible power supply comprises a photovoltaic power supply.

14. The wind turbine generator of claim 1 wherein the uninterruptible power supply comprises one or more capacitors.

15. A wind turbine generator comprising:

a generator;

a power converter coupled with the generator, the power converter having an inverter coupled to receive power from the generator, a converter controller coupled with the inverter to monitor a current flow in the inverter, and a circuit coupled with the input of the inverter and with the converter controller to shunt current from the inverter and generator rotor in response to a control signal from the converter controller.

16. The wind turbine generator of claim 15 wherein the circuit comprises a crowbar circuit.

17. The wind turbine generator of claim 15 wherein the converter controller is coupled to the generator to receive power during a first mode of operation and to an uninterruptible power supply to receive power during a low voltage event.

18. The wind turbine generator of claim 17 wherein the uninterruptible power supply comprises a battery power supply.

19. The wind turbine generator of claim 17 wherein the uninterruptible power supply comprises a photovoltaic power supply.

20. The wind turbine generator of claim 17 wherein the uninterruptible power supply comprises one or more capacitors.

21. The wind turbine generator of claim 17 further comprising:

a blade pitch control system to vary a pitch of one or more blades; and

a turbine controller coupled with the blade pitch control system, wherein the turbine controller detects a transition from the first mode of operation and causes the blade pitch control system to vary the pitch of the one or more blades in response to the transition.

22. The wind turbine generator of claim 17 wherein the second mode of operation comprises a low voltage event.

23. The wind turbine generator of claim 22 wherein a low voltage event comprises a generator output voltage of less than 75% of a rated voltage for the generator.

24. The wind turbine generator of claim 23 wherein the low voltage event occurs for up to 3 seconds.

25. The wind turbine generator of claim 22 wherein a low voltage event comprises a generator output voltage of less than 50% of a rated voltage for the generator.

26. The wind turbine generator of claim 25 wherein the low voltage event occurs for up to 3 seconds.

27. The wind turbine generator of claim 22 wherein a low voltage event comprises a generator between 15% and 50% of a rated voltage for the generator.

28. The wind turbine generator of claim 27 wherein the low voltage event occurs for up to 3 seconds.

29. A method comprising:

providing power to wind turbine components using a generator of the wind turbine;

detecting a low voltage event;

receiving power from an uninterruptible power supply to a first subset of wind turbine components, wherein the first subset of wind turbine components comprises a blade pitch controller to selectively power the blade pitch controller to maintain a rotor speed below a predetermined overspeed limit during the low voltage event; and

disconnecting a second subset of wind turbine components from the generator during the low voltage event.

30. The method of claim 29 wherein the uninterruptible power supply comprises a battery power supply.

31. The wind turbine generator of claim 29 wherein the uninterruptible power supply comprises a photovoltaic power supply.

32. The wind turbine generator of claim 29 wherein the uninterruptible power supply comprises one or more capacitors.

33. The method of claim 29 wherein a low voltage event comprises a generator output voltage of less than 75% of a rated voltage for the generator.

34. The method of claim 33 wherein the low voltage event occurs for up to 3 seconds.

35. The method of claim 29 wherein a low voltage event comprises a generator output voltage of less than 50% of a rated voltage for the generator.

36. The method of claim 35 wherein the low voltage event occurs for up to 3 seconds.

37. The method of claim 29 wherein a low voltage event comprises a generator between 15% and 50% of a rated voltage for the generator.

38. The method of claim 37 wherein the low voltage event occurs for up to 3 seconds.

39. An apparatus comprising:

means for providing power to wind turbine components using a generator of the wind turbine;

means for detecting a low voltage event;

means for providing power from an uninterruptible power supply to a first subset of wind turbine components, wherein the first subset of wind turbine components comprises a blade pitch controller to selectively power the blade pitch controller to maintain a rotor speed below a predetermined overspeed limit during the low voltage event; and

means for disconnecting a second subset of wind turbine components from the generator during the low voltage event.

40. The apparatus of claim 39 wherein a low voltage event comprises a generator output voltage of less than 75% of a rated voltage for the generator.

41. The apparatus of claim 40 wherein the low voltage event occurs for up to 3 seconds.

42. The apparatus of claim 39 wherein a low voltage event comprises a generator output voltage of less than 50% of a rated voltage for the generator.

43. The apparatus of claim 42 wherein the low voltage event occurs for up to 3 seconds.

44. The apparatus of claim 39 wherein a low voltage event comprises a generator between 15% and 50% of a rated voltage for the generator.

45. The apparatus of claim 44 wherein the low voltage event occurs for up to 3 seconds.