Wind turbine blade and manufacturing method thereof

Abstract

The present invention discloses a wind turbine blade and a manufacturing method thereof. The wind turbine blade includes a blade root portion, the blade root portion is provided with a first embedded bolt sleeve assembly connected to a wheel hub, and the first embedded bolt sleeve assembly is distributed along the circumferential direction of the blade root portion, the side wall of the blade root portion is provided with a boss, and a second embedded bolt sleeve assembly connected to the wheel hub is arranged in the boss, the boss includes a first end portion and a second end portion opposite to each other, the threaded hole opening of the second embedded bolt sleeve assembly is located at the end face of the first end portion, and the thickness of the second end portion gradually decreases in a direction away from the first end portion. The boss provided with the second embedded bolt sleeve assembly in the present invention increases the number of bolts of the wind turbine blade, reduces the load of a single bolt in the blade root portion, and improves the safety of the use of the wind turbine blade. In addition, only adding the second embedded bolt sleeve assembly locally can effectively reduce the weight of the blade root portion and the weight of the entire machine head compared to adding a row of second embedded bolt sleeve assemblies in the entire circle design of the side wall of the blade root portion.

Description

Technical Field

[0001] The invention relates to a wind turbine blade and a manufacturing method thereof. Background Art

[0002] Embedded bolt sleeves are currently the most commonly used method in blade root connection design. As the design length of wind turbine blades becomes longer and longer, the blade root load becomes larger and larger, and the ultimate load and fatigue damage of the blade root bolts increase. Therefore, during the use of wind turbines, the bolts are prone to deformation and fracture, which in turn affects the safety of wind turbines. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defect that during the use of the wind turbine, the bolts connecting the wind turbine blades and the hub are easily deformed or broken due to excessive load, which affects the safety of the wind turbine, and provide a wind turbine blade and a manufacturing method thereof.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] The present invention provides a wind turbine blade, which includes a blade root portion, wherein the blade root portion is provided with a first embedded bolt sleeve assembly connected to a wheel hub, and the first embedded bolt sleeve assembly is distributed along the circumferential direction of the blade root portion, and the side wall of the blade root portion is provided with a boss, and a second embedded bolt sleeve assembly connected to the wheel hub is arranged in the boss, and the boss includes a first end portion and a second end portion opposite to each other, and a threaded hole opening of the second embedded bolt sleeve assembly is located on the end face of the first end portion, and a thickness of the second end portion gradually decreases in a direction away from the first end portion.

[0006] In the present scheme, the above-mentioned structural form is adopted. On the first hand, the number of bolts of the wind turbine blade is increased, the load of a single bolt in the blade root is reduced, the bearing capacity of the blade root is improved, deformation, breakage, etc. caused by excessive load on the bolts are avoided, and the safety of the use of the wind turbine blade is further increased; on the second hand, only the boss and the second embedded bolt sleeve assembly are added locally. Compared with adding a row of second embedded bolt sleeve assemblies in the entire circle of the inner wall or outer wall of the blade root, the weight of the blade root and the weight of the whole machine head can be effectively reduced, and the load of the whole machine can be reduced; on the third hand, the blade root pitch circle diameter can be reduced under the condition of a certain bolt bearing capacity, thereby reducing the size of the hub and the bearing connecting the hub and the blade root, and reducing the production cost of the whole machine; on the fourth hand, the thickness of the second end of the boss gradually decreases in the direction away from the first end, that is, the thickness of the boss close to the tip of the wind turbine blade gradually decreases, so as to reduce the gap between the boss and the blade root and enhance the overall strength of the wind turbine blade.

[0007] Preferably, the side end of the boss has a slope surface, and the slope surface extends from the inner wall surface of the boss toward the outer side of the side end of the boss to the inner wall surface of the blade root.

[0008] In this solution, the above-mentioned structural form is adopted, and a slope is set on the boss, so that the upper surface layer of the boss slowly transitions on both sides of the boss, avoiding the occurrence of wrinkles and reducing stress concentration.

[0009] Preferably, a filling piece is provided between the blade root portion and the second end portion, the filling piece is used to fill the gap between the blade root portion and the second end portion, and the filling piece has an inclined surface flush with an end surface of the second end portion.

[0010] In this solution, the above-mentioned structural form is adopted, and the thickness of the blade root near the tip of the wind turbine blade gradually decreases. The filling piece can fill the decreasing thickness area of ​​the blade root, so that the inner surface of the blade root meets the requirement of flush placement of the boss.

[0011] Preferably, the blade root and the boss are fixed by means of structural adhesive.

[0012] In this solution, the above-mentioned structural form is adopted, and the boss is bonded to the side wall of the blade root using structural adhesive to form a local double-row bolt structure, which has a good fixing effect and the boss is not easy to fall off.

[0013] The present invention also provides a method for manufacturing a wind turbine blade, which is used to manufacture the wind turbine blade as described above, and the manufacturing method comprises the following steps:

[0014] S1. Modeling the wind turbine blade, and performing load analysis on the blade root of the wind turbine blade, and calculating the area of ​​the blade root with the largest load and the lowest safety;

[0015] S2. Calculating the number of the second embedded bolt sleeve assemblies required to be added according to the area, and obtaining a boss mold for manufacturing the boss according to the required number of the second embedded bolt sleeve assemblies and the inner wall radius of the blade root;

[0016] S3, forming the boss in the boss mold.

[0017] In the present solution, on the first hand, the boss provided with the second embedded bolt sleeve assembly can increase the number of bolts in the lowest safety area of ​​the blade root, reduce the load of a single bolt in this area, and increase the safety of the use of wind turbine blades; on the second hand, only locally adding the boss and the second embedded bolt sleeve assembly can effectively reduce the weight of the blade root and the weight of the whole machine head, thereby reducing the load of the whole machine, compared to adding a row of second embedded bolt sleeve assemblies to the entire circle of the inner wall or the outer wall of the blade root; on the third hand, under the condition of a certain bolt bearing capacity, the blade root pitch circle diameter can be reduced, thereby reducing the size of the hub and the bearing connecting the hub and the blade root, thereby reducing the cost of the whole machine.

[0018] Preferably, the manufacturing method further comprises the following steps:

[0019] S4. Laminating, pouring and curing are performed in the wind turbine blade mold to form a wind turbine blade that does not include the boss.

[0020] In this solution, the wind turbine blade is modeled, the root of the wind turbine blade is subjected to load analysis, and after calculating the area of ​​the blade root with the largest load and the lowest safety, the wind turbine blade is layered, poured, and cured in the wind turbine blade mold to form a wind turbine blade without a boss. This is to prevent the pre-manufactured wind turbine blade without a boss from being inconsistent with the wind turbine blade that needs to be subjected to load analysis, resulting in the need for rework and affecting the manufacturing progress.

[0021] Preferably, step S4 includes:

[0022] S41, placing the ply material of the wind turbine blade in the wind turbine blade mold;

[0023] S42, laying the first embedded bolt sleeve assembly;

[0024] S43, pouring resin and curing to form a wind turbine blade that does not include the boss.

[0025] Preferably, the manufacturing method further comprises the following steps:

[0026] S5. Fix the boss to the maximum load-bearing area in the blade root of the wind turbine blade that does not include the boss.

[0027] In this solution, the boss is installed at the root of the blade by structural adhesive to form a local double-row bolt structure, which enhances the bearing capacity of the wind turbine blade, has a good fixing effect, and the boss is not easy to fall off.

[0028] Preferably, before step S5, a filling piece is laid in the maximum loaded area so that the inner surface of the blade root meets the requirement of flush placement of the boss.

[0029] In this solution, laying the filling piece can fill the decreasing thickness area of ​​the blade root, so that the inner surface of the blade root meets the requirement of flush placement of the boss. In addition, the filling piece can fill the gap between the boss and the blade root, expand the installation surface of the boss, and greatly reduce the possibility of the boss falling off during the use of the wind turbine blade.

[0030] Preferably, step S3 includes:

[0031] S31, laying glass fiber cloth in the boss mold;

[0032] S32, laying the second embedded bolt sleeve assembly in the boss mold, and placing a wedge block on both sides of the second embedded bolt sleeve respectively;

[0033] S33, pouring resin and curing to form the boss.

[0034] In this solution, a second embedded bolt sleeve assembly is laid in the mold to form a boss, and the wedge block makes the two ends of the boss have a slope extending from the inner wall of the boss toward the outer side of the side end of the boss to the inner wall of the blade root, so that the upper glass fiber cloth in the boss slowly transitions on both sides of the boss, avoiding the occurrence of wrinkles and reducing stress concentration.

[0035] The positive and progressive effect of the present invention is that the boss provided with the second embedded bolt sleeve assembly in the present invention increases the number of bolts of the wind turbine blade, reduces the load of a single bolt in the blade root, avoids deformation, breakage, etc. caused by excessive load on the bolt, and thus increases the safety of the use of the wind turbine blade. In addition, only adding the boss and the second embedded bolt sleeve assembly locally can effectively reduce the weight of the blade root and the weight of the whole machine head, and reduce the load of the whole machine, compared with adding a row of second embedded bolt sleeve assemblies to the entire circle of the inner wall or outer wall of the blade root. And under the condition of a certain bolt bearing capacity, the pitch circle diameter of the blade root can be reduced, thereby reducing the size of the hub and the bearing connecting the hub and the blade root, and reducing the cost of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of a wind turbine blade according to a preferred embodiment of the present invention.

[0037] Figure 2 This is a schematic structural diagram of a wind turbine blade at another angle according to a preferred embodiment of the present invention.

[0038] Figure 3 This is a schematic structural diagram of a wind turbine blade at another angle according to a preferred embodiment of the present invention.

[0039] Figure 4 It is a schematic structural diagram of a boss according to a preferred embodiment of the present invention.

[0040] Figure 5The figure is a flow chart of a method for manufacturing a wind turbine blade according to a preferred embodiment of the present invention.

[0041] Description of reference numerals:

[0042] Leaf root 1

[0043] The first embedded bolt sleeve assembly 11

[0044] Boss 2

[0045] The second embedded bolt sleeve assembly 21

[0046] Slope 22

[0047] Wedge block 23

[0048] Filler 3 DETAILED DESCRIPTION

[0049] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the following examples.

[0050] An embodiment of the present invention provides a wind turbine blade, such as Figure 1 , Figure 2 and Figure 3 As shown. The wind turbine blade includes a blade root 1, and the blade root 1 is provided with a first embedded bolt sleeve assembly 11 connected to the hub, and the first embedded bolt sleeve assembly 11 is distributed along the circumferential direction of the blade root 1, and the blade root 1 is installed on the wind turbine through the first embedded bolt sleeve assembly 11. The side wall of the blade root 1 is provided with a boss 2, and the boss 2 can be arranged on the inner side wall or outer side wall of the blade root 1. The boss 2 is provided with a second embedded bolt sleeve assembly 21 connected to the hub, and the wind turbine blade is installed on the hub, and the second embedded bolt sleeve assembly 21 is added locally on the outer side or inner wall of the blade root 1. Among them, the second embedded bolt sleeve assembly 21 is arranged correspondingly to the first embedded bolt sleeve assembly 11, or the second embedded bolt sleeve assembly 21 is arranged alternately with the first embedded bolt sleeve assembly 11. The boss 2 includes a first end and a second end opposite to each other, and the threaded hole opening of the second embedded bolt sleeve assembly 21 is located on the end face of the first end, and the thickness of the second end gradually decreases in the direction away from the first end.

[0051] In this embodiment, the wind turbine blade adopts the above structure. On the one hand, the number of bolts of the wind turbine blade is increased, the load of a single bolt in the blade root 1 is reduced, the bearing capacity of the blade root is improved, and the bolts are prevented from being deformed or broken due to excessive load, thereby increasing the safety of the wind turbine blade. On the other hand, only the boss 2 and the second embedded bolt sleeve assembly 21 are locally added. Compared with adding a row of second embedded bolt sleeve assemblies 21 in the entire circle design of the inner wall or outer wall of the blade root 1, the weight of the blade root 1 and the weight of the whole machine head can be effectively reduced. Reduce the load of the whole machine; thirdly, by increasing the number of blade root bolts, the blade root pitch circle diameter can be reduced under the condition of a certain bolt load-bearing capacity, thereby reducing the size of the hub and the bearing connecting the hub to the blade root 1, and reducing the cost of the whole machine; fourthly, the thickness of the blade tip close to the wind turbine blade in the blade root 1 gradually decreases, and the thickness of the second end of the boss 2 gradually decreases in the direction away from the first end, that is, the thickness of the boss 2 close to the blade tip of the wind turbine blade gradually decreases, so as to reduce the gap between the boss 2 and the blade root 1 and enhance the overall strength of the wind turbine blade.

[0052] Preferably, the load analysis of the blade root 1 is performed through simulation calculation to find the bolt area with the largest load and the lowest safety. In this area, a boss 2 is added and a second embedded bolt sleeve assembly 21 is arranged in the boss 2, which greatly improves the load-bearing capacity of the blade root 1 and the safety of the blade root bolts, reduces the possibility of bolt breakage and deformation in the bolt area with the lowest safety, and further increases the safety of wind turbine blades.

[0053] like Figure 4 As shown, the side end of the boss 2 has a slope 22, and the slope 22 extends from the inner wall of the boss 2 to the outer side of the side end of the boss 2 to the inner wall of the blade root 1. The slope 22 is arranged on the boss 2 so that the upper surface of the boss 2 slowly transitions on both sides of the boss 2, thereby avoiding the occurrence of wrinkles and reducing stress concentration. Specifically, both sides of the boss 2 extend from the inner wall of the boss 2 to the outer side of the side end of the boss 2 to the inner wall of the blade root 1.

[0054] like Figure 4 As shown, a filler 3 is provided between the blade root 1 and the second end portion, and the filler 3 is used to fill the gap between the blade root 1 and the second end portion, and the filler 3 has an inclined surface flush with the end surface of the second end portion. The thickness of the blade root 1 near the tip of the wind turbine blade gradually decreases, and the filler 3 can fill the decreasing thickness area of ​​the blade root 1 and fill the gap between the boss 2 and the blade root 1, thereby expanding the mounting surface of the boss 2, greatly reducing the possibility of the boss 2 falling off during the use of the wind turbine blade, and making the inner surface of the blade root 1 meet the requirement of the boss 2 being placed flush.

[0055] The blade root 1 and the boss 2 are fixed by structural adhesive. The boss 2 is bonded to the side wall of the blade root 1 by structural adhesive to form a local double-row bolt structure, which has a good fixing effect and the boss 2 is not easy to fall off.

[0056] The embodiment of the present invention provides a method for manufacturing a wind turbine blade, which is used to manufacture a wind turbine blade as described in any of the above embodiments, such as Figure 5 As shown, the manufacturing method comprises the following steps:

[0057] S1. Modeling a wind turbine blade, and performing a load analysis on the blade root 1 of the wind turbine blade, and calculating the area of ​​the blade root 1 with the largest load and the lowest safety;

[0058] S2. Calculate the number of the second embedded bolt sleeve assemblies 21 required to be added according to the calculated area on the blade root 1 with the largest load and the lowest safety, and obtain a boss mold for manufacturing the boss 2 according to the required number of the second embedded bolt sleeve assemblies 21 and the inner wall radius of the blade root 1;

[0059] S3. Forming a boss 2 in a boss mold.

[0060] In this embodiment, according to the calculated area with the lowest safety on the blade root 1, the number of the second embedded bolt sleeve assemblies 21 to be added is calculated to obtain the boss mold and manufacture the boss 2, and the boss 2 provided with the second embedded bolt sleeve assembly 21 is used to be fixed in the area with the lowest safety on the blade root 1. In the first aspect, the boss provided with the second embedded bolt sleeve assembly 21 can increase the number of bolts in the area with the lowest safety in the blade root 1, reduce the load of a single bolt in the area, avoid deformation, breakage, etc. caused by excessive load on the bolt, and thus increase the safety of the use of the wind turbine blade. In the second aspect, only adding the boss 2 and the second embedded bolt sleeve assembly 21 locally can effectively reduce the weight of the blade root 1 and the weight of the whole machine head, and reduce the load of the whole machine, compared with adding a row of second embedded bolt sleeve assemblies 21 to the inner side wall or outer side wall of the blade root 1. In the third aspect, increasing the number of blade root bolts can reduce the blade root pitch circle diameter under the condition of a certain bolt bearing capacity, thereby reducing the size of the hub and the bearing connecting the hub and the blade root 1, and reducing the cost of the whole machine.

[0061] The method for manufacturing a wind turbine blade also includes the following steps: S4, performing layering, pouring, and curing in a wind turbine blade mold to form a wind turbine blade that does not include the boss 2. In the specific operation, the wind turbine blade is modeled, the blade root 1 of the wind turbine blade is subjected to load analysis, and after calculating the area of ​​the blade root 1 with the largest load and the lowest safety, layering, pouring, and curing are performed in the wind turbine blade mold to form a wind turbine blade that does not include the boss 2. This is to prevent the pre-manufactured wind turbine blade that does not include the boss 2 from being inconsistent with the wind turbine blade that needs to be subjected to load analysis, resulting in the need for rework, which affects the manufacturing progress.

[0062] Step S4 includes:

[0063] S41, placing a ply material of a wind turbine blade in a wind turbine blade mold;

[0064] S42, laying the first embedded bolt sleeve assemblies 11, placing prefabricated auxiliary materials between each first embedded bolt sleeve assembly 11, and the ends of the prefabricated auxiliary materials connected to the first embedded bolt sleeve assemblies 11 are arranged in an arc shape, that is, the first embedded bolt sleeve assemblies 11 are laid at intervals, and prefabricated auxiliary materials are laid between every two first embedded bolt sleeve assemblies 11 to fix the first embedded bolt sleeve assemblies 11;

[0065] S43 , pouring resin into the wind turbine blade mold, curing, and closing the mold to form a wind turbine blade without the boss 2 .

[0066] In this embodiment, the first embedded bolt sleeve assembly 11 is laid in the mold and a wind turbine blade without the boss 2 is formed, which is convenient for operation.

[0067] The method for manufacturing a wind turbine blade further includes the following steps: S5, fixing the boss 2 to the maximum load-bearing area in the blade root 1 of the wind turbine blade that does not include the boss 2. The boss 2 is installed on the blade root 1 by structural adhesive to form a local double-row bolt structure, thereby enhancing the load-bearing capacity of the wind turbine blade, achieving a good fixing effect, and preventing the boss 2 from falling off easily.

[0068] Before step S5, a filler is laid in the maximum load area of ​​the blade root 1, so that the inner surface of the blade root 1 meets the requirement of flush placement of the boss 2. Before installing the boss 2, a filler is laid in the maximum load area of ​​the blade root 1 of the already formed wind turbine blade that does not include the boss 2, so that the inner surface of the blade root 1 meets the requirement of flush placement of the boss 2. In addition, the filler 3 can fill the gap between the boss 2 and the blade root 1, expand the installation surface of the boss 2, and greatly reduce the possibility of the boss 2 falling off during the use of the wind turbine blade.

[0069] Of course, in other embodiments, the boss 2 may be first installed in the area of ​​the blade root 1 that is subject to the greatest load, and then the filling piece may be laid in the area of ​​the blade root 1 that is subject to the greatest load.

[0070] Step S3 includes:

[0071] S31, laying glass fiber cloth in the boss mold, that is, laying upper glass fiber cloth and lower glass fiber cloth in the boss mold;

[0072] S32, laying the second embedded bolt sleeve assembly 21 in the boss mold, laying the second embedded bolt sleeve assembly 21 between the upper fiberglass cloth and the lower fiberglass cloth, laying prefabricated auxiliary materials between every two second embedded bolt sleeve assemblies 21 to fix the second embedded bolt sleeve assembly 21, and placing a wedge block 23 on both sides of the second embedded bolt sleeve respectively;

[0073] S33, pouring resin and curing to form boss 2.

[0074] In this embodiment, the second embedded bolt sleeve assembly 21 is laid in the mold to form a boss, and the tip of the wedge block 23 faces the outside of the boss mold, providing chamfering of the edge of the boss 2, so that both ends of the boss 2 have a slope 22 extending from the inner wall of the boss 2 to the outer side of the side end of the boss 2 to the inner wall of the blade root 1, so that the upper glass fiber cloth in the boss 2 slowly transitions on both sides of the boss 2 to avoid wrinkles and reduce stress concentration. Among them, the wedge block is a triangular cross-section pultrusion elongation condition, which can be a unidirectional glass fiber reinforced resin composite material.

[0075] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A wind turbine blade, comprising a blade root, wherein the blade root is provided with a first embedded bolt sleeve assembly connected to a hub, and the first embedded bolt sleeve assembly is distributed along the circumferential direction of the blade root, characterized in that: The side wall of the blade root is provided with a boss, a second embedded bolt sleeve assembly connected to the wheel hub is arranged in the boss, the boss includes a first end and a second end opposite to each other, the threaded hole opening of the second embedded bolt sleeve assembly is located on the end surface of the first end, and the thickness of the second end gradually decreases in a direction away from the first end; A filling piece is provided between the blade root portion and the second end portion, and the filling piece is used to fill a gap between the blade root portion and the second end portion. The filling piece has an inclined surface that is flush with an end surface of the second end portion.

2. The wind turbine blade according to claim 1, characterized in that: The side end of the boss has a slope surface, and the slope surface extends from the inner wall surface of the boss toward the outer side of the side end of the boss to the inner wall surface of the blade root.

3. The wind turbine blade according to claim 1, characterized in that: The blade root and the boss are fixed by structural adhesive.

4. A method for manufacturing a wind turbine blade, characterized in that: It is used to manufacture the wind turbine blade according to any one of claims 1 to 3, and the manufacturing method comprises the following steps: S1. Modeling the wind turbine blade, and performing load analysis on the blade root of the wind turbine blade, and calculating the area of ​​the blade root with the largest load and the lowest safety; S2. Calculating the number of the second embedded bolt sleeve assemblies required to be added according to the area, and obtaining a boss mold for manufacturing the boss according to the required number of the second embedded bolt sleeve assemblies and the inner wall radius of the blade root; S3, forming the boss in the boss mold.

5. The method for manufacturing a wind turbine blade according to claim 4, characterized in that: The manufacturing method further comprises the following steps: S4. Laminating, pouring and curing are performed in the wind turbine blade mold to form a wind turbine blade that does not include the boss.

6. The method for manufacturing a wind turbine blade according to claim 5, characterized in that: Step S4 includes: S41, placing the ply material of the wind turbine blade in the wind turbine blade mold; S42, laying the first embedded bolt sleeve assembly; S43, pouring resin and curing to form a wind turbine blade that does not include the boss.

7. The method for manufacturing a wind turbine blade according to claim 6, characterized in that: The manufacturing method further comprises the following steps: S5. Fix the boss to the maximum load-bearing area in the blade root of the wind turbine blade that does not include the boss.

8. The method for manufacturing a wind turbine blade according to claim 7, characterized in that: Before step S5, a filling piece is laid in the maximum loaded area so that the inner surface of the blade root meets the requirement of flush placement of the boss.

9. The method for manufacturing a wind turbine blade according to claim 4, characterized in that: Step S3 includes: S31, laying glass fiber cloth in the boss mold; S32, laying the second embedded bolt sleeve assembly in the boss mold, and placing a wedge block on both sides of the second embedded bolt sleeve respectively; S33, pouring resin and curing to form the boss.

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