Wind turbine blade

Patent metadata

Field	Value
Publication number	US-9970412-B2
Application number	US-201514667479-A
Country	US
Kind code	B2
Filing date	Mar 24, 2015
Priority date	Sep 26, 2012
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A wind turbine blade comprising a fairing with a rigid structural component ( 12 ) which forms the majority of the aerodynamic profile and a non-actively controllable elastically deformable trailing edge component ( 14 ) mounted on the structural component to complete the aerodynamic profile. The trailing edge component ( 14 ) is formed from a material having an elastic modulus in the range of 0.5 to 2.5 GPa such it will elastically buckle when loading on the trailing edge component exceeds a predetermined threshold. The structural component ( 12 ) comprises a unidirectional reinforcing layer adjacent to the trailing edge component with at least one layer of unidirectional fibers ( 26 ) extending in a substantially spanwise direction.

First claim

What is claimed is:

1. A wind turbine blade comprising a fairing having an aerodynamic profile, the fairing comprising:
a rigid structural component which forms the majority of the aerodynamic profile, the structural component comprising a trailing edge; and
a non-actively controllable elastically deformable trailing edge component mounted to the trailing edge of the structural component to complete the aerodynamic profile,
wherein the trailing edge component is formed from a material having an elastic modulus in the range of 0.5 to 2.5 GPa such that it elastically buckles when loading on the trailing edge component exceeds a predetermined threshold, and
wherein the structural component comprises a unidirectional reinforcing layer extending across the trailing edge from a suction side to a pressure side of the aerodynamic profile and adjacent to the trailing edge component, the unidirectional reinforcing layer comprising at least one layer of unidirectional fibres extending in a substantially spanwise direction, the trailing edge component extending in the spanwise direction beyond the spanwise extent of the unidirectional reinforcing layer.

2. The wind turbine blade of claim 1 , wherein the structural component further comprises an additional unidirectional reinforcing layer adjacent to its leading edge, the additional unidirectional reinforcing layer comprising at least one layer of unidirectional fibres extending in a substantially spanwise direction.

3. The wind turbine blade of claim 1 , wherein the structural component is formed from a fibre reinforced plastic and the unidirectional reinforcing layer and/or an additional unidirectional reinforcing layer is co-cured with the fibre reinforced plastic such that it is an integral part of the structural component.

4. The wind turbine blade of claim 1 , wherein the unidirectional reinforcing layer and/or an additional unidirectional reinforcing layer comprises a concentrated region of at least two layers of unidirectional fibres extending in a substantially spanwise direction.

5. The wind turbine blade according to claim 4 , wherein the concentrated region comprises at least one layer of multiaxial fibres.

6. The wind turbine blade of claim 5 , wherein a ratio of the layers of unidirectional fibres to multiaxial fibres in the concentrated region is at least 5:1.

7. The wind turbine blade of claim 4 , wherein the concentrated region extends along less than half of a span of the fairing.

8. The wind turbine blade of claim 1 , wherein the chordwise dimension of the trailing edge component increases in the spanwise direction towards the blade tip.

9. The wind turbine blade of claim 1 , wherein the structural component has a blunt trailing edge in the vicinity of the blade root and the trailing edge component is absent at this point.

10. The wind turbine blade of claim 1 , wherein the trailing edge component extends in the spanwise direction beyond the spanwise extent of an additional unidirectional reinforcing layer.

11. The wind turbine blade of claim 10 , wherein the trailing edge component extends beyond the spanwise extent of the unidirectional reinforcing layer and/or an additional unidirectional reinforcing layer towards the blade tip.

12. The wind turbine blade of claim 1 , wherein the trailing edge component is able to sustain elastically a strain of greater than 2%.

13. The wind turbine blade of claim 1 , wherein the trailing edge component is made from a material selected from a group including rubber, silicon, acetal, ABS, nylon, acrylic, PBT, PET, polypropylene, PU, TPO, and polyethylene.

14. The wind turbine blade of claim 1 , wherein the trailing edge component has a trailing edge tip thickness of less than 5 mm.

15. The wind turbine blade of claim 1 , wherein the chordwise dimension of the trailing edge component at its widest point represents less than 25% of the chord length of the aerodynamic profile.

16. The wind turbine blade of claim 1 , wherein the chordwise dimension of the trailing edge component is at its widest point inward of the blade tip and decreases from its widest point towards the blade tip.

17. The wind turbine blade of claim 1 , wherein the trailing edge of the aerodynamic profile at the blade tip is formed by the structural component, whereas the trailing edge component is absent at this point.

18. The wind turbine blade of claim 1 , wherein the trailing edge component comprises a unitary piece extending across at least 1 meter of the span of the fairing, preferably the unitary piece extends across at least 10 meters of the span of the fairing, more preferably the unitary piece extends across at least 20 meters of the span of the fairing.

19. The wind turbine blade of claim 1 , wherein the structural component has a closed cross-section.

20. The wind turbine blade of claim 19 , wherein an trailing edge end of the closed cross-section is defined by a structural wall on which the trailing edge component is mounted.

21. The wind turbine blade of claim 1 , wherein the trailing edge component is non-pivotally mounted on the structural component.

22. The wind turbine blade of claim 1 , wherein the trailing edge component is mounted on the structural component using a groove and boltrope arrangement.

23. The wind turbine blade of claim 1 , wherein the trailing edge is mounted on the structural component using a locking clip.

24. The wind turbine blade of claim 1 , wherein the aerodynamic profile formed by the structural component and the trailing edge component is continuous.

25. A method of preventing buckling of a trailing edge of a wind turbine blade having a fairing with an aerodynamic profile, the method comprising:
providing a rigid structural component that forms a majority of the aerodynamic profile, the structural component having a trailing edge;
mounting a non-actively controllable elastically deformable trailing edge component to the flat trailing edge of the structural component to complete the aerodynamic profile, the trailing edge component being formed from a material having an elastic modulus in the range of 0.5 to 2.5 GPa, the structural component having a unidirectional reinforcing layer extending across the trailing edge from a suction side to a pressure side of the aerodynamic profile and adjacent to the trailing edge component, the unidirectional reinforcing layer comprising at least one layer of unidirectional fibres extending in a substantially spanwise direction, the trailing edge component extending in the spanwise direction beyond the spanwise extent of the unidirectional reinforcing layer; and
allowing the trailing edge component to elastically buckle when loading on the trailing edge component exceeds a predetermined threshold.

26. The wind turbine blade of claim 1 , wherein the trailing edge of the structural component is flat.

27. The method of claim 25 , wherein the trailing edge of the structural component is flat.

Assignees

• Blade Dynamics Ltd

Inventors

• Hayden Paul
• Gutierrez Joaquin

Classifications

• F03D13/10

  Assembly of wind motors; Arrangements for erecting wind motors · CPC title

• F05B2240/311

  flexible or elastic · CPC title

• F03D1/0675 Primary

  of the blades · CPC title

• F01D5/28

  Selecting particular materials; {Particular measures relating thereto;} Measures against erosion or corrosion · CPC title

• F01D5/3092

  Protective layers between blade root and rotor disc surfaces, e.g. anti-friction layers (F01D5/288 takes precedence) · CPC title