LEADING EDGE PROTECTION OF A WIND TURBINE BLADE

Abstract

The invention relates to a method of preparing a wind turbine blade with a leading edge protection. The method includes applying a first layer of paint on the surface portion comprising the part of the leading edge to be protected, applying a layer of a fibrous material on top of the first layer of paint, applying a second layer of paint on the layer of fibrous material, and allowing the applied leading edge protection to cure. The method may be performed as a part of the manufacture of the blade and/or as a post-processing step for example during repair on site. The proposed method results in an increased erosion resistance and improved protection against impacting particles. The invention further relates to a wind turbine blade comprising a leading edge protection established as mentioned above.

Claims

1. A method of preparing a wind turbine blade with a leading edge protection, the wind turbine blade extending a length between a root end and a tip end of the blade, and extending a width between a trailing edge and a leading edge, the wind turbine blade comprising an outer surface portion comprising at least a part of the leading edge, the method comprising: applying a first layer of paint on the surface portion of the blade, applying a layer of a fibrous material on top of the first layer of paint, applying a second layer of paint on the layer of fibrous material, allowing the applied leading edge protection to cure, and wherein the second layer of paint is applied to at least partially impregnate the layer of fibrous material.

2. (canceled)

3. A method of preparing a wind turbine blade according to claim 1, wherein the layer of fibrous material comprises a dry fibrous material.

4. A method of preparing a wind turbine blade according to claim 1, wherein the layer of fibrous material comprises a weave or a random fibre mat.

5. A method of preparing a wind turbine blade according to claim 1, wherein the fibrous material comprises fibres of at least one material belonging to the group of glass fibre, polyester, Kevlar, and nylon.

6. A method of preparing a wind turbine blade according to claim 1, wherein the first and second layers of paint are of the same material.

7. A method of preparing a wind turbine blade according to claim 1, wherein the paint is a coating comprising a two-component polyurethane coating, a three component polyurethane coating, an epoxy resin, or a polyester resin.

8. A method of preparing a wind turbine blade according to claim 1, the method further comprising applying alternatingly a further layer of fibrous material and a further layer of paint thereby laying up a plurality of layers of fibrous material with layers of paint in between.

9. A method of preparing a wind turbine blade according to claim 1, wherein the layers of paint are applied by rolling, brushing, or spraying.

10. A method of preparing a wind turbine blade according to claim 1, the method further comprising applying a peel ply as the outermost layer prior to curing, peeling off the peel ply after curing, and applying a layer of a paint as an outermost layer.

11. A method of preparing a wind turbine blade according claim 10, wherein the peel ply is applied to cover an edge of the outermost applied layer of fibrous material and is pressed into the uncured paint.

12. A method of preparing a wind turbine blade according to claim 1, wherein the method steps form part of a manufacture of the wind turbine blade.

13. A method of preparing a wind turbine blade according to claim 1, wherein the method steps are performed as post processing during repair or maintenance of the wind turbine blade.

14. A wind turbine blade extending a length between a root end and a tip end of the blade, and extending a width between a trailing edge and a leading edge, the wind turbine blade comprising an outer surface portion comprising at least a part of the leading edge, wherein the wind turbine blade further comprises a leading edge protection prepared according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In the following different embodiments of the invention will be described with reference to the drawings, wherein:

[0037] FIG. 1 shows a wind turbine,

[0038] FIG. 2 shows a wind turbine blade comprising a leading edge protection,

[0039] FIG. 3 illustrates a part of a wind turbine blade as seen in a cross-sectional view and comprising a leading edge protection according to embodiments of the invention, and

[0040] FIGS. 4A-C illustrate the method of preparing a blade with a leading edge protection according to embodiments of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0041] FIG. 1 shows a wind turbine 100 comprising a tower 101, a nacelle 102 at the tower top, the nacelle housing machine components, such as gearbox, generator etc. (not shown). At one end of the nacelle, a hub section 103 supports a plurality of wind turbine blades 110.

[0042] FIG. 2 shows a wind turbine blade 110 extending a length 201 between a root end 202 and a tip end 203 of the blade, and extending a width between a trailing edge 205 and a leading edge 206 as indicated by the arrow 204. An outer surface portion 210 of the wind turbine blade covers a part of the leading edge 206 and is provided with a leading edge protection according to the invention.

[0043] FIG. 3 illustrates a part of the wind turbine blade 101 as seen in a cross-sectional view and corresponding to the indicated profile 300 in FIG. 2. The outer or exterior surface portion 210 of the blade covers and extends across the leading edge 206 of the blade. The leading edge protection comprises a first layer of paint 301 applied to the surface portion 210, a layer of a fibrous material 302, and a further layer of a paint 303 applied on top of and impregnating and wetting out the fibrous material.

[0044] The successive steps in the application method are illustrated in FIG. 4A-C. In a first step illustrated in FIG. 4A, a first layer of paint 301 is applied to the surface portion 210 and such as to cover the leading edge. The paint may for example be applied by brush, roller or spray 401. Then (FIG. 4B) the layer of fibrous material 302 is applied on top of the paint 301. The fibrous layer may for example be a weave or mat, or may comprise fibres of for example glass fibre, nylon, Kevlar or polyester or combinations hereof. If desired, the fibrous layer 302 may be applied as multiple patches for example of more easily handled sizes or to better drape on the curved outer surface of the blade. The fibrous layer may be pressed slightly into the paint.

[0045] Then in a following step (FIG. 4C) is applied a second layer of paint 303 impregnating the fibrous layer 302. Again, the paint may for example be applied by brush, roller or spray 401 as convenient. Hereafter the leading edge protection can be left to cure.

[0046] A leading edge protection of even further increased thickness may be realized by the application of more layers of fibrous material with layers of paint in between, i.e. repeating the steps of FIGS. 4B and 4C a number of times such as to apply for example 2, 3, 4, 5, or 6 layers of fibrous material. The fibrous material in the different layers may be the same, partially the same or all different.

[0047] While preferred embodiments of the invention have been described, it should be understood that the invention is not so limited and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.