Variable rotor speed wind turbine, wind park, method of transmitting electric power and method of servicing or inspecting a variable rotor speed wind turbine

• US 9,306,473 B2
• Filed: 07/01/2005
• Issued: 04/05/2016
• Est. Priority Date: 07/01/2005
• Status: Expired due to Fees

• Current Assignee: Vestas Wind Systems A/S
• Original Assignee: Vestas Wind Systems A/S
• Inventors: Kjaer, Philip Richard Jacobsen Carne, Helle, Lars
• Primary Examiner(s): Patel, Tulsidas C
• Assistant Examiner(s): MIKAILOFF, STEFAN
• Application Number:
  US11/993,512
• Publication Number:
  US 20090224607A1
• Time in Patent Office: 3,931 Days
• Field of Search: 290/44, 290/55
• US Class Current: 1/1
• CPC Class Codes: F03D 13/20 Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
• CPC Class Codes: F03D 9/255 connected to electrical distribution networks; Arrangements therefor
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/38 Arrangements for parallely feeding a single network by two or more generators, converters or transformers
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02M 1/325 with means for allowing continuous operation despite a fault, i.e. fault tolerant converters
• CPC Class Codes: H02M 5/458 using semiconductor devices only
• CPC Class Codes: H02M 7/493 the static converters being arranged for operation in parallel
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/728 Onshore wind turbines
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

The invention relates to a variable rotor speed wind turbine transmitting AC electric power to a utility grid. The wind turbine includes at least one AC generator and at least two power electronic converter units. Further, it includes means for transforming at least one nominal output value of the generator to at least one different nominal input value of the at least two power electronic converter units. The invention also relates to a wind park and a method of transmitting AC electric power to a utility grid from a variable rotor speed wind turbine as well as a method of servicing or inspecting a variable rotor speed wind turbine.

Claims

1. A variable rotor speed wind turbine transmitting electric AC power to a utility grid, the wind turbine comprising:

at least one AC generator;

a power converter comprising at least three power electronic converter units each configured to perform AC-DC-AC conversion;

at least one nominal output value transformer communicatively coupling the at least one AC generator and the power converter, and configured to transform at least one nominal output value of the at least one AC generator to at least one different nominal input value of the at least three power electronic converter units; and

at least one utility grid transformer coupled to the power converter, wherein the nominal output value transformer, the utility grid transformer and the power converter transform phases of the at least one AC generator to at least three phases of the utility grid,

wherein the nominal output value transformer, the utility grid transformer, and at least one of the power electronic converter units form a power module provided to the wind turbine, and wherein the power module is included in a common housing with one or more additional power modules corresponding to different wind turbines,

wherein an organization and location of the power electronic converter units enables redundancy in the wind turbine by N-1 operation.

2. The variable rotor speed wind turbine according to claim 1 wherein the at least one AC generator is a polyphase synchronous or asynchronous AC generator.

3. The variable rotor speed wind turbine according to claim 2 wherein the at least one AC generator is a synchronous generator magnetised electrically or by permanent magnets.

4. The variable rotor speed wind turbine according to claim 2 wherein the at least one AC generator is a low-speed, high pole-number synchronous generator.

5. The variable rotor speed wind turbine according to claim 1 wherein each of the power electronic converter units have a same nominal rating or are of a same type.

6. The variable rotor speed wind turbine according to claim 1 wherein the nominal output value transformer comprises a fixed transformation ratio.

7. The variable rotor speed wind turbine according to claim 1 wherein the nominal output value transformer transforms a nominal generator voltage and/or number of phases.

8. The variable rotor speed wind turbine according to claim 7 wherein the nominal output value transformer transforms a nominal voltage output value of the at least one AC generator to a different nominal voltage input value of the power converter.

9. The variable rotor speed wind turbine according to claim 8 wherein the nominal output value transformer transforms a high voltage to a lower voltage below 3300 volts.

10. The variable rotor speed wind turbine according to claim 9 wherein the high voltage is chosen between the values of:

3300, 4160, 6600, 10000, 11000 and 13200 volts, and the lower voltage is chosen between values of 690, 1000, 2200 and 3300 volts per power electronic converter unit.

11. The variable rotor speed wind turbine according to claim 1, wherein the nominal output value transformer transforms a number of phases of current or voltage of the at least one AC generator to a different number of phases of current or voltage of the power converter.

12. The variable rotor speed wind turbine according to claim 1 wherein the nominal output value transformer, the utility grid transformer and the power converter transform three phases of the at least one AC generator to at least three phases of the utility grid.

13. The variable rotor speed wind turbine according to claim 1 wherein the at least one utility grid transformer transforms an output voltage rating and/or a number of phases of the power converter to the utility grid.

14. The variable rotor speed wind turbine according to claim 1 wherein the at least one utility grid transformer steps up a nominal output voltage of the power converter.

15. The variable rotor speed wind turbine according to claim 1 wherein the at least one of the at least three power electronic converter units is located in a tower of the wind turbine at a lower part of the tower such as at or in proximity of the tower foundation.

16. The variable rotor speed wind turbine according to claim 1 wherein each of the at least three power electronic converter units includes switchgear including a first switchgear in a connection before each of the at least three power electronic converter units and a second switchgear in a connection after each of the at least three power electronic converter units.

17. The variable rotor speed wind turbine according to claim 16 wherein the power module includes the at least three power electronic converter units and the switchgear.

18. The variable rotor speed wind turbine according to claim 1 wherein the number of power electronic converter units is between 3 and 10 parallel units.

19. The variable rotor speed wind turbine according to claim 1, wherein the variable rotor speed wind turbine is located in a wind park comprising a plurality of wind turbines.

20. The variable rotor speed wind turbine according to claim 1, wherein at least one of the power electronic converter units is located at a foundation of a tower of the wind turbine.

21. The variable rotor speed wind turbine according to claim 1, wherein the power module is provided within a separate enclosure to the wind turbine.

22. The variable rotor speed wind turbine according to claim 1, wherein each additional power module corresponds to a respective wind turbine.

23. The variable rotor speed wind turbine according to claim 1 wherein the at least three power electronic converter units of the power converter are included in the power module.

24. A method of transmitting electric power to an AC utility grid from a variable rotor speed wind turbine, the method comprising:

generating AC power with at least one AC generator;

transforming at least one nominal output value of the at least one AC generator to at least one different nominal input value of a power converter with at least one nominal output value transformer communicatively coupling the at least one AC generator and the power converter;

converting the power to the AC utility grid with the power converter, the power converter comprising at least three power electronic converter units each configured to perform AC-DC-AC conversion; and

transforming at least one value of the power converter to at least one different input value of the AC utility grid with at least one utility grid transformer coupled to the power converter, wherein the nominal output value transformer, the utility grid transformer, and the power converter transform phases of the at least one AC generator to at least three phases of the utility grid,

wherein the nominal output value transformer, the utility grid transformer, and at least one of the power electronic converter units form a power module provided to the wind turbine, and wherein the power module is included in a common housing with one or more additional power modules corresponding to different wind turbines, and

wherein an organization and location of the power electronic converter units enables redundancy in the wind turbine by N-1 operation.

25. The method of transmitting electric power to an AC utility grid according to claim 24, where the at least three power electronic converter units are connected or disconnected from the nominal output value transformer using switchgear coupled to the at least three power electronic converter units.

26. The method of transmitting electric power to an AC utility grid according to claim 25, wherein the switchgear disconnects one of the at least three power electronic converter units, wherein one or more of the at least three power electronic converter units that are not disconnected are controlled to a value close to a nominal power rating of the at least three power electronic converter units.

27. The method of claim 24 wherein the at least three power electronic converter units of the power converter are included in the power module.

28. A method of servicing or inspecting a variable rotor speed wind turbine transmitting electric AC power to a utility grid, the method comprising:

transforming at least one nominal output value of at least one AC generator to at least one different nominal input value of a power converter, the power converter comprising at least three power electronic converter units each configured to perform AC-DC-AC conversion, with at least one nominal output value transformer communicatively coupling the at least one AC generator and the power converter;

transforming at least one nominal value of the power converter with at least one utility grid transformer coupled to the power converter, wherein the nominal output value transformer, the utility grid transformer, and the power converter transform phases of the at least one AC generator to at least three phases of the utility grid;

disconnecting one of the at least three power electronic converter units under servicing or inspection of the unit from the nominal output value and utility grid transformers using a switchgear; and

operating, after disconnecting the one power electronic converter unit, the remaining power electronic converter units of the wind turbine in N-1 operation,

wherein the nominal output value transformer, the utility grid transformer, and at least one of the power electronic converter units form a power module provided to the wind turbine, and wherein the power module is included in a common housing with one or more additional power modules corresponding to different wind turbines.

29. A variable rotor speed wind turbine for transmitting electric AC power to a utility grid, the wind turbine comprising:

at least one AC generator;

a power converter comprising at least three power electronic converter units each configured to perform AC-DC-AC conversion, wherein each of the power electronic converter units comprises a rectifier and an inverter;

at least one nominal output value transformer communicatively coupling the at least one AC generator and the power converter, and configured to transform a high voltage output from the at least one AC generator to a lower voltage input to the power converter that is below 3300 volts; and

at least one utility grid transformer coupled to the power converter and configured to transform a low voltage to a higher voltage above 3300 volts, wherein the at least one nominal output value transformer, the at least one utility grid transformer and the power converter transform phases of the at least one AC generator to at least three phases of the utility grid,

wherein the nominal output value transformer, the utility grid transformer, and at least one of the power electronic converter units form a power module provided to the wind turbine, and wherein the power module is included in a common housing with one or more additional power modules corresponding to different wind turbines,

wherein the power converter comprises a plurality of rectifiers and a plurality of inverters, wherein an organization and location of the plurality of rectifiers and the plurality of inverters enable redundancy in the wind turbine by N-1 operation.

30. The variable rotor speed wind turbine according to claim 29, wherein at least one of the power electronic converter units is located at a foundation of a tower of the wind turbine.

31. The variable rotor speed wind turbine according to claim 29 wherein the at least three power electronic converter units of the power converter are included in the common housing.