Wind power blade root pre-embedded structure with high bearing capacity and blade with wind power blade root pre-embedded structure

Abstract

The invention discloses a high-bearing-capacity wind power blade root pre-embedded structure and a blade thereof. The blade root pre-embedded structure comprises a pre-embedded bolt sleeve, a wedge-shaped strip, a foam strip and an omega-shaped clamp. The multiple embedded bolt sleeves are arranged along the blade root at intervals, a wedge-shaped strip is arranged between every two adjacent embedded bolt sleeves, and the tail ends of the embedded bolt sleeves are connected with foam strips after being sealed. The omega-shaped clamp is arranged between the embedded bolt sleeve and the wedge-shaped strip, an annular groove is formed in the outer surface of the embedded bolt sleeve, the omega-shaped clamp is clamped in the annular groove, and the two ends of the omega-shaped clamp are in lap joint with the wedge-shaped strip; after the omega-shaped clamp is adopted, yarn does not need to be wound on the surface of the embedded bolt sleeve any more, and the situation that cavities occur when the bolt sleeve is poured, and the interface bonding performance is greatly reduced is reduced. Therefore, the blade can adopt a smaller blade root pitch circle diameter under the condition of the same load, the sizes of platforms such as a hub and a variable pitch bearing of a unit are effectively reduced, and the comprehensive cost of the wind turbine generator is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of design and application of wind turbine blades, and in particular to a high-load-bearing wind turbine blade root pre-embedded structure and a blade thereof. Background Art

[0002] As an important new energy source, wind energy has been widely used and vigorously developed. Blades are important components of wind turbines. Usually, wind turbine blades are connected to the hub of the whole machine through the blade root connection area. In order to capture more wind energy and increase the power generation of wind turbines, the length of wind turbine blades has been increasing in recent years, and the load on the blade roots has also been increasing, which has put higher requirements on the connection strength between the root of the wind turbine blade and the hub.

[0003] In the prior art, there are usually two ways to connect the blade root to the whole machine pitch bearing: T-type punching type and pre-embedded blade root bolt sleeve type. As the length of the blade continues to increase, the bending moment on the blade root becomes larger and larger. The pre-embedded blade root bolt sleeve connection method is more commonly used in the industry, that is, before the blade is cast, a pre-embedded bolt sleeve is placed at the root of the blade mold, and a wedge-shaped strip is placed between the pre-embedded bolt sleeves for filling. After casting, the pre-embedded bolt sleeve and other glass fiber materials of the blade root are solidified and formed into one. This process method can arrange more connecting bolts at the blade root to ensure that the blade root connecting bolts have sufficient ultimate strength and fatigue strength.

[0004] In this type of embedded bolt sleeve molding process, the outer surface of the embedded bolt sleeve is often designed to be threaded or annular grooves, and the surface of the screw sleeve is often wrapped with yarn before the shell is poured to enhance the interface bonding performance between the embedded bolt sleeve and the wedge strip. However, even so, the contact surface between the screw sleeve and the wedge strip is still small. After the resin is poured, it is still easy to form resin-rich accumulation or pouring cavity around the embedded bolt sleeve. The resin-rich accumulation or pouring cavity will greatly reduce the interface adhesion. After the blade is loaded, the blade root is subjected to a large load, which may cause the embedded bolt sleeve to be pulled out from the root of the blade, causing the connection between the root of the blade and the hub to become loose or even fall off, thereby causing equipment damage or causing safety accidents. Therefore, how to improve the bonding performance of the interface between the embedded bolt sleeve and the fiberglass to improve product reliability is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a high-load-bearing capacity wind turbine blade root pre-embedded structure and a blade thereof, which can enhance the load-bearing capacity of the blade root by improving the wind turbine blade root pre-embedded structure.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect of the present invention, a high-load-bearing capacity wind turbine blade root embedded structure is provided, comprising an embedded bolt sleeve, a wedge strip, a foam strip and an Ω-shaped clip; a plurality of embedded bolt sleeves are arranged at intervals along the blade root, a wedge strip is arranged between two adjacent embedded bolt sleeves, and the ends of the embedded bolt sleeves are sealed and connected to the foam strip; the Ω-shaped clip is arranged between the embedded bolt sleeve and the wedge strip, an annular groove is arranged on the outer surface of the embedded bolt sleeve, the Ω-shaped clip is clamped in the annular groove, and the two ends of the Ω-shaped clip are overlapped on the wedge strip.

[0008] In some embodiments of the present invention, the Ω-shaped clamp includes a circular arc segment in the middle and non-circular arc segments at both ends, the cross-section of the circular arc segment is trapezoidal, the non-circular arc segment is a plane, and the non-circular arc segment overlaps the wedge strip.

[0009] In some embodiments of the present invention, the wedge-shaped bar is a waist-shaped wedge-shaped bar, and segmented grooves are provided on the upper and lower surfaces of the wedge-shaped bar, and the non-circular arc segments at both ends of the Ω-shaped clip are placed in the segmented grooves.

[0010] In some embodiments of the present invention, the diameter of the Ω-shaped clip arc segment is larger than the diameter of the annular groove and smaller than the outer diameter of the embedded bolt sleeve.

[0011] In some embodiments of the present invention, the Ω-shaped clamps are designed as a single unit, and each of the Ω-shaped clamps connects an embedded bolt sleeve and wedge-shaped strips on both sides thereof.

[0012] In some embodiments of the present invention, the Ω-shaped clamps are designed in multiple combinations, and each of the Ω-shaped clamps connects multiple embedded bolt sleeves and wedge-shaped strips on both sides of each embedded bolt sleeve.

[0013] In some embodiments of the present invention, a plurality of annular grooves are provided along the axial direction of the embedded bolt sleeve, an Ω-shaped clip is installed on each annular groove, and the opening directions of adjacent Ω-shaped clips are opposite.

[0014] In some embodiments of the present invention, multiple annular grooves are arranged along the axial direction of the embedded bolt sleeve, and an Ω-shaped clip is installed on each annular groove. The opening directions of multiple Ω-shaped clips on the same embedded bolt sleeve are the same, and the opening directions of the Ω-shaped clips on adjacent embedded bolt sleeves are the same or opposite.

[0015] In some embodiments of the present invention, the surface of the Ω-shaped clamp is roughened.

[0016] In a second aspect of the present invention, a blade is provided, comprising the blade root pre-embedded structure described in the first aspect, and further comprising an upper cloth layer and a lower cloth layer, wherein the upper cloth layer is located above the blade root pre-embedded structure, and the lower cloth layer is located below the blade root pre-embedded structure.

[0017] One or more technical solutions of the present invention have the following beneficial effects:

[0018] The present invention provides a novel wind turbine blade embedded root connection technology, and combines it with the blade root structure design to improve the bearing capacity of the blade root. It is mainly achieved by installing an Ω-shaped clip between the blade embedded bolt sleeve and the wedge strip. The Ω-shaped clips can be installed in groups of several, and the embedded bolt sleeve and the wedge strip are connected together in groups, which can greatly increase the contact area between the embedded bolt sleeve and the wedge strip. After the resin is vacuum injected, the embedded bolt sleeve, the Ω-shaped clip and the wedge strip are effectively integrated into one, which can greatly improve the upper limit of the tensile pull-out force that the root embedded bolt sleeve can withstand.

[0019] The high-load-bearing wind turbine blade root structure provided by the present invention adopts an Ω-shaped clamp and the embedded bolt sleeve surface no longer needs to be wrapped with yarn, which reduces the occurrence of cavities during the injection of the screw sleeve, which greatly reduces the interface bonding performance. As a result, the blade can adopt a smaller blade root pitch circle diameter under the same load condition, effectively reducing the platform size of the unit hub, pitch bearing, etc., and reducing the comprehensive cost of the wind turbine unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a high-load-bearing-capacity wind turbine blade root structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the assembly of the pre-embedded structure of the blade root of a wind turbine blade with high load-bearing capacity of the present invention;

[0022] Figure 3 It is a structural schematic diagram of the embedded bolt sleeve of the present invention;

[0023] Figure 4 It is a schematic structural diagram of a single Ω-shaped clip of the present invention;

[0024] Figure 5 It is a schematic diagram of assembling a single Ω-shaped clip and an embedded bolt sleeve of the present invention;

[0025] Figure 6 It is a schematic structural diagram of the combined Ω-shaped clip of the present invention;

[0026] Figure 7 It is a schematic diagram of assembling the combined Ω-shaped clip and the embedded bolt sleeve of the present invention;

[0027] Figure 8 It is a schematic diagram of the upper surface of the first arrangement mode when the Ω-shaped clip of the present invention is assembled;

[0028] Fig. 9 It is a schematic diagram of the lower surface of the first arrangement mode when the Ω-shaped clip of the present invention is assembled;

[0029] Fig.10A schematic diagram of the upper surface of the second arrangement mode of the Ω-shaped clip of the present invention when assembled;

[0030] Fig.11 It is a schematic diagram of the lower surface of the second arrangement mode when the Ω-shaped clip of the present invention is assembled.

[0031] In the figure: 1, upper cloth layer; 2, lower cloth layer; 3, embedded structure of blade root; 31, embedded bolt sleeve; 311, annular groove; 32, wedge strip; 33, Ω-shaped clip; 331, arc segment; 332, non-arc segment; 34, foam strip. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] Example 1

[0034] In a typical embodiment of the present invention, a high-load-bearing wind turbine blade root pre-embedded structure is proposed, such as Figure 1-4 As shown, it includes an embedded bolt sleeve 31, a wedge strip 32, a foam strip 34 and an Ω-shaped clip 33; a plurality of embedded bolt sleeves 31 are arranged at intervals along the blade root, a wedge strip 32 is arranged between two adjacent embedded bolt sleeves 31, and the ends of the embedded bolt sleeves 31 are sealed and connected to the foam strip 34; the Ω-shaped clip 33 is arranged between the embedded bolt sleeve 31 and the wedge strip 32, and an annular groove 311 is arranged on the outer surface of the embedded bolt sleeve 31, the Ω-shaped clip 33 is clamped in the annular groove 311, and the two ends of the Ω-shaped clip 33 are overlapped on the wedge strip 32.

[0035] like Figure 4 As shown, the Ω-shaped clip 33 includes a circular arc segment 331 in the middle and non-circular arc segments 332 at both ends. The cross section of the circular arc segment 331 is trapezoidal, and the non-circular arc segment 331 is a plane. The non-circular arc segment 331 overlaps the wedge strip.

[0036] Furthermore, the wedge-shaped strip 32 adopts a waist-shaped wedge-shaped strip, and segmented grooves are arranged on the upper surface and the lower surface of the wedge-shaped strip 32. The shape of the segmented groove matches the shape of the non-circular arc segments 332 at both ends of the Ω-shaped clip 33. The non-circular arc segments 332 at both ends of the Ω-shaped clip 33 are placed in the segmented grooves, and the mating surface can be designed to be a rough surface to increase the pull-out resistance.

[0037] In this embodiment, the diameter of the Ω-shaped clamp arc segment 331 is larger than the diameter of the annular groove 311 and smaller than the outer diameter of the embedded bolt sleeve 31. The cross-section of the arc segment 331 is trapezoidal, and the cross-sectional shape of the arc segment is designed to match the shape of the annular groove of the embedded bolt sleeve. When the embedded bolt sleeve is subjected to external pulling force, the Ω-shaped clamp can effectively connect it to the wedge bar.

[0038] like Figure 4 and Figure 5 As shown, the Ω-shaped clips 33 are designed as a single unit, and each of the Ω-shaped clips connects an embedded bolt sleeve 31 and wedge-shaped strips 32 on both sides thereof.

[0039] like Figure 6 and Figure 7 The Ω-shaped clip 33 adopts a plurality of combined designs, and each of the Ω-shaped clips 33 connects a plurality of embedded bolt sleeves 31 and wedge-shaped strips 32 on both sides of each embedded bolt sleeve, further increasing the tensile bearing capacity of the embedded blade root structure.

[0040] like Figure 8 and Fig. 9 As shown, a plurality of annular grooves are arranged along the axial direction of the embedded bolt sleeve, and an Ω-shaped clip is installed on each annular groove, and the opening directions of adjacent Ω-shaped clips are opposite so that the Ω-shaped clips can transmit force evenly.

[0041] like Fig.10 and Fig.11 As shown, multiple annular grooves are arranged along the axial direction of the embedded bolt sleeve, and an Ω-shaped clip is installed on each annular groove. The opening directions of multiple Ω-shaped clips on the same embedded bolt sleeve are the same, and the opening directions of the Ω-shaped clips on adjacent embedded bolt sleeves are the same; of course, the opening directions of the Ω-shaped clips on adjacent embedded bolt sleeves are opposite.

[0042] In this embodiment, only some arrangements or installation forms are listed, and other connection devices or other installation arrangements to increase the bonding force between the embedded screw sleeve and the wedge strip can be expanded and applied in series.

[0043] In this embodiment, the surface of the Ω-shaped clip 33 is roughened, the roughened arc segment 331 cooperates with the annular groove 311 of the embedded bolt sleeve 31, and the roughened non-arc segment 332 cooperates with the upper and lower end surfaces of the wedge strip 32, which is beneficial to increase the interface bonding force while effectively combining the embedded bolt sleeve, the wedge strip and the upper and lower cloth layers into one, replacing the traditional thread sleeve winding process.

[0044] Example 2

[0045] In a typical embodiment of the present invention, a blade is proposed, comprising the blade root pre-embedded structure described in Example 1, and also comprising an upper cloth layer 1 and a lower cloth layer 2, wherein the upper cloth layer 1 is located above the blade root pre-embedded structure 3, and the lower cloth layer 2 is located below the blade root pre-embedded structure 3.

[0046] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A high-load-bearing wind turbine blade root pre-embedded structure, characterized in that: It includes an embedded bolt sleeve, a wedge strip, a foam strip and an Ω-shaped clip; a plurality of embedded bolt sleeves are arranged at intervals along the root of the blade, a wedge strip is arranged between two adjacent embedded bolt sleeves, and the ends of the embedded bolt sleeves are sealed and connected to the foam strip; the Ω-shaped clip is arranged between the embedded bolt sleeve and the wedge strip, an annular groove is arranged on the outer surface of the embedded bolt sleeve, the Ω-shaped clip is clamped in the annular groove, and the two ends of the Ω-shaped clip are overlapped on the wedge strip.

2. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: The Ω-shaped clip comprises a circular arc segment in the middle and non-circular arc segments at both ends. The cross section of the circular arc segment is a trapezoid, and the non-circular arc segment is a plane. The non-circular arc segment is overlapped on the wedge-shaped strip.

3. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 2, characterized in that: The wedge-shaped strip is a waist-shaped wedge-shaped strip, and segmented grooves are arranged on the upper surface and the lower surface of the wedge-shaped strip, and the non-circular arc segments at both ends of the Ω-shaped clip are placed in the segmented grooves.

4. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 2, characterized in that: The diameter of the Ω-shaped clamp arc segment is larger than the diameter of the annular groove and smaller than the outer diameter of the embedded bolt sleeve.

5. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: The Ω-shaped clamp adopts a single design, and each of the Ω-shaped clamps is connected to an embedded bolt sleeve and wedge-shaped strips on both sides thereof.

6. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: The Ω-shaped clamps are designed in multiple combinations, and each of the Ω-shaped clamps connects multiple embedded bolt sleeves and wedge-shaped strips on both sides of each embedded bolt sleeve.

7. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: A plurality of annular grooves are arranged along the axial direction of the embedded bolt sleeve, and an Ω-shaped clip is installed on each annular groove, and the opening directions of adjacent Ω-shaped clips are opposite.

8. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: The annular grooves are arranged in plurality along the axial direction of the embedded bolt sleeve, and an Ω-shaped clip is installed on each annular groove. The opening directions of the plurality of Ω-shaped clips on the same embedded bolt sleeve are the same, and the opening directions of the Ω-shaped clips on adjacent embedded bolt sleeves are the same or opposite.

9. The high-load-bearing capacity wind turbine blade root pre-embedded structure according to claim 1, characterized in that: The surface of the Ω-shaped clip is roughened.

10. A blade, comprising the blade root pre-embedded structure according to any one of claims 1 to 9, characterized in that: It also includes an upper fabric layer and a lower fabric layer, wherein the upper fabric layer is located above the blade root pre-embedded structure, and the lower fabric layer is located below the blade root pre-embedded structure.

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