Wind turbine blade

Abstract

The present application relates to a wind turbine blade. The wind turbine blade comprises two or more blade modules, reinforcing members, and an adhesive body. The blade modules are spliced in the length direction of the wind turbine blade. Each blade module comprises a load-carrying beam and a covering layer. The load-carrying beam comprises an abutting inclined surface and an abutting end surface which are connected. The covering layer covers the abutting inclined surface and the abutting end surface. The stiffness of the covering layer is less than the stiffness of the load-carrying beam. Any two adjacent blade modules are abutted against each other, and the corresponding abutting inclined surfaces overlap each other. The reinforcing members cover a gap formed by abutting of two adjacent load-carrying beams, and the reinforcing members connect the two adjacent load-carrying beams. The stiffness of the reinforcing members is less than the stiffness of the load-carrying beam. The covering layers corresponding to the abutting inclined surfaces of the two load-carrying beams are bonded to each other by means of the adhesive body, and the reinforcing members and the covering layers are bonded to each other by means of the adhesive body. The wind turbine blade provided by the present application is beneficial for reducing the possibility of cracking failure occurring between the two load-carrying beams due to stress concentration, thereby prolonging the service life of the wind turbine blade.

Description

Wind turbine blades

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese patent application 202411505274.6 entitled "Wind Turbine Blade", filed on October 25, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of wind power generation, and in particular to a wind turbine blade. Background Technology

[0004] As wind turbine blades become increasingly longer, the cost and difficulty of their transportation increase significantly. To reduce transportation difficulties and substantially save on transportation costs, segmented blades are the main development trend. The primary purpose of connecting segmented blades is to ensure the continuous and effective load transfer of load-bearing beams such as the main beam, secondary beam, or trailing edge beam. This connection is generally achieved through bonding, pinning, bolting, or other methods.

[0005] Referring to Figure 1, the prior art discloses a segmented blade, which includes a first blade segment and a second blade segment. The first blade segment and the second blade segment are spliced ​​along the length direction of the blade. The first blade segment includes a first beam segment. The first beam segment has a first mating inclined surface 1A and a first mating end face 1B. The second blade segment includes a second beam segment. The second beam segment has a second mating inclined surface 1C and a second mating end face 1D. When the first blade segment and the second blade segment are mated, the first mating inclined surface 1A and the second mating inclined surface 1C overlap and are bonded together.

[0006] However, as shown in Figure 2, the segmented blades described above have significant stress concentrations at both the first and second mating surfaces. This can easily lead to fatigue fracture at the connection between the first and second blade segments, thus affecting the service life of the segmented blades.

[0007] Summary of the Invention

[0008] This application provides a wind turbine blade that helps reduce the possibility of cracking failure due to stress concentration between two load-bearing beams and improves the service life of the wind turbine blade.

[0009] This application provides a wind turbine blade, which includes two or more blade modules, reinforcing members, and adhesive bodies.

[0010] Each blade module is spliced ​​along the length of the wind turbine blade. Each blade module includes a load-bearing beam and a cover layer. The load-bearing beam includes a connected docking ramp and a docking end face. The cover layer covers the docking ramp and the docking end face. The stiffness of the cover layer is less than that of the load-bearing beam. Any two adjacent blade modules are docked, and the docking ramps overlap each other.

[0011] The stiffener covers the gap formed by the butt joint of two adjacent load-bearing beams and connects the two adjacent load-bearing beams. The stiffener's stiffness is less than that of the load-bearing beam.

[0012] The cover layers corresponding to the mating slopes of the two load-bearing beams, as well as the reinforcement and cover layers, are bonded together by adhesives.

[0013] In the wind turbine blade of this embodiment, a covering layer is provided on the butt joint of the load-bearing beam. The covering layer covers the butt joint bevel and the butt joint end face. The stiffness of the covering layer is less than the stiffness of the load-bearing beam. The stiffness of the reinforcing member is less than the stiffness of the load-bearing beam. The covering layer can change the force transmission path. Therefore, the force transmission path between the two load-bearing beams includes load-bearing beam-covering layer-adhesive body-reinforcing member-adhesive body-covering layer-load-bearing beam, which can help disperse the force, reduce stress concentration at the apex of the load-bearing beam, reduce the possibility of cracking failure due to stress concentration between the butt joint end face and the adhesive body, and improve the service life of the wind turbine blade.

[0014] In some feasible implementations, the cover layer comprises multiple layers stacked along the thickness direction of the cover layer.

[0015] The connection strength and load-bearing capacity of the covering layer, which includes multiple layers, can be improved.

[0016] In some feasible methods, the edges of each layer corresponding to the mating end face are staggered, and each layer has a protruding portion that extends beyond the mating end face along the length direction, with each protruding portion having a different length.

[0017] The edges of each layer corresponding to the mating end face are staggered to reduce the possibility of stress concentration in the edge area of ​​the cover layer, which helps to improve the load-bearing capacity of the cover layer.

[0018] In some feasible implementations, the cover layer is a single-layer structure, with each cover layer staggered at the edge corresponding to the mating end face, and the cover layer has an overhang that extends beyond the mating end face along the length direction, with each overhang having a different length.

[0019] The staggered arrangement of the edges of each cover layer and the mating end face helps to reduce the possibility of stress concentration in the edge area of ​​the cover layer and improves the load-bearing capacity of the cover layer.

[0020] In some feasible implementations, in two adjacent blade modules, the overhang of one blade module overlaps the cover layer of the other blade module, and the overhang covers the gap formed by the abutment of the two adjacent load-bearing beams.

[0021] The extended portion of the cover layer can be used in conjunction with the reinforcement to connect the two load-bearing beams, thereby improving the connection strength and load-bearing capacity of the two load-bearing beams. Simultaneously, the force transmission path between the two load-bearing beams can also include load-bearing beam-cover layer-adhesive body-cover layer-load-bearing beam, which increases the number of force transmission paths, helps disperse forces, and reduces the possibility of stress concentration in the load-bearing beams.

[0022] In some feasible implementations, a reinforcement covers the extended portion. The reinforcement can provide protection for the extended portion.

[0023] In some feasible implementations, the length of the portion extending closer to the reinforcing member is greater than the length of the portion extending further away from the reinforcing member.

[0024] Along the length of the wind turbine blade, the stiffness of the cover layer at the extended portion can gradually decrease, i.e., the change is slow rather than abrupt, which helps to further reduce the possibility of stress concentration at the edge of the cover layer.

[0025] In some feasible ways, the covering extends beyond the reinforcement along the length.

[0026] In the completed load-bearing beam, along the length direction, the stiffeners have a cover layer on both sides, which helps to ensure that a connection area is formed between the stiffener and the cover layer, thereby improving the connection strength and load-bearing capacity between the cover layer and the stiffener.

[0027] In some feasible ways, the elastic modulus of the covering layer is greater than or equal to 8 GPa and less than or equal to 20 GPa.

[0028] In some feasible embodiments, the cover layer includes a first fiber and a second fiber, the first fiber extending in a first direction and the second fiber extending in a second direction, the first direction being at an angle of 30° to 60° with respect to the length direction and the second direction being at an angle of 30° to 60° with respect to the length direction.

[0029] In some feasible ways, the adhesive material includes thermosetting adhesives or thermoplastic resins.

[0030] In some feasible ways, the reinforcement includes fiberglass fabric. Attached Figure Description

[0031] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0032] Figure 1 is a schematic diagram of a partial structure of a wind turbine blade in a related technology;

[0033] Figure 2 is a schematic diagram of the stress distribution at the joint end face of the segmented blade shown in Figure 1;

[0034] Figure 3 is a schematic diagram of the structure of a wind turbine generator set provided in some embodiments of this application;

[0035] Figure 4 is a schematic diagram of the structure of a wind turbine blade provided in some embodiments of this application;

[0036] Figure 5 is a partial cross-sectional view of a wind turbine blade provided in some embodiments of this application;

[0037] Figure 6 is a partial structural schematic diagram of the wind turbine blade of the relevant technology;

[0038] Figure 7 is a partial structural schematic diagram of the blade module provided in some embodiments of this application;

[0039] Figure 8 is a partial structural schematic diagram of a wind turbine blade provided in some embodiments of this application;

[0040] Figure 9 is a partial structural schematic diagram of a wind turbine blade provided in some embodiments of this application;

[0041] Figure 10 is a partial structural schematic diagram of the blade module provided in some embodiments of this application;

[0042] Figure 11 is a partial structural diagram of the cover layer provided in some embodiments of this application.

[0043] The accompanying drawings are not necessarily drawn to scale.

[0044] Explanation of reference numerals in the attached drawings: 10, wind turbine generator set; 20, wind turbine blade; 30, shell; 40, load-bearing beam; 41, mating ramp; 42, mating end face; 50, blade module; 60, reinforcing member; 70, adhesive body; 80, cover layer; 801, protruding part; 802, first fiber; 803, second fiber; 81, layer; X, length direction; Y1, first direction; Y2, second direction. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0047] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0048] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0049] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0050] In this application, "multiple" means two or more (including two).

[0051] Figure 3 schematically shows the structure of a wind turbine generator set 10. Referring to Figure 3, an embodiment of this application provides a wind turbine generator set 10. The wind turbine generator set 10 includes a tower, a nacelle, and a wind turbine. The nacelle is located at the top of the tower. The wind turbine includes a hub and wind turbine blades 20. The wind turbine blades 20 are connected to the hub. The hub is connected to the main shaft of the nacelle. The wind turbine blades 20 can generate torque under the action of wind. The wind turbine blades 20 and the hub drive the main shaft of the nacelle to rotate, thereby converting wind energy into mechanical energy. The main shaft of the nacelle can be connected to the rotor of a generator, thereby converting mechanical energy into electrical energy.

[0052] Figure 4 schematically shows the structure of the wind turbine blade 20. Figure 5 schematically shows a partial cross-sectional view of the wind turbine blade 20. Referring to Figures 4 and 5, an embodiment of this application provides a wind turbine blade 20. The wind turbine blade 20 includes a load-bearing beam 40 and a housing 30. The load-bearing beam 40 can be connected to the housing 30.

[0053] In the related art, Figure 6 schematically shows a partial structure of a wind turbine blade 20. Referring to Figure 6, when two load-bearing beams 40 are directly bonded together by an adhesive 70, stress concentration occurs at the two apex corners D1 and D2 of the mating end faces 42 of the load-bearing beams 40. This poses a possibility that the wind turbine blade 20 may crack at these apex corners during subsequent use. One approach is to use a separate reinforcing member 60 to connect the two load-bearing beams 40, thereby reducing stress concentration at apex corner D1. However, further research by the inventors revealed that due to the high stiffness of each of the two load-bearing beams 40, the force between the two directly bonded load-bearing beams 40 has a transmission path of load-bearing beam 40-adhesive 70-load-bearing beam 40, resulting in significant stress concentration still occurring at apex corner D2.

[0054] Figure 7 schematically shows a partial structure of the blade module 50. Figure 8 schematically shows a partial structure of the wind turbine blade 20. Referring to Figures 2, 7, and 8, an embodiment of this application provides a wind turbine blade 20, which includes two or more blade modules 50, a reinforcing member 60, and an adhesive body 70.

[0055] Each blade module 50 is spliced ​​along the length X of the wind turbine blade 20. Each blade module 50 includes a load-bearing beam 40 and a cover layer 80. The load-bearing beam 40 includes connected mating ramps 41 and mating end faces 42. The cover layer 80 covers the mating ramps 41 and mating end faces 42. The stiffness of the cover layer 80 is less than that of the load-bearing beam 40. Any two adjacent blade modules 50 are mated together, with the mating ramps 41 overlapping each other. A reinforcing member 60 covers the gap formed by the mating of two adjacent load-bearing beams 40 and connects the two adjacent load-bearing beams 40. The stiffness of the reinforcing member 60 is less than that of the load-bearing beam 40. The cover layers 80 corresponding to the mating ramps 41 of the two load-bearing beams 40, as well as the reinforcing member 60 and the cover layer 80, are bonded together by an adhesive 70.

[0056] In this embodiment, each blade module 50 can be manufactured individually and transported to the construction site using transportation equipment. Then, the blade modules 50 are connected to each other to form a complete wind turbine blade 20. Therefore, for wind turbine blades 20 with a length of 100 meters or more, this manufacturing method helps reduce transportation difficulty and costs.

[0057] After the load-bearing beam 40 is formed, a butt joint bevel 41 is cut at one end by machining, while the uncut and thickened area forms the butt joint end face 42. When the two blade modules 50 are docked, the load-bearing beams 40 of the two blade modules 50 can be docked with each other at the butt joint bevel 41, and the two load-bearing beams 40 are connected by the reinforcing member 60 and the adhesive body 70.

[0058] In this embodiment, the load-bearing beam 40 can be a main beam, a secondary beam, or a trailing edge beam. The load-bearing beam 40 can be formed by pultruded plates or injection-molded laminates, etc. In the fabric constituting the corresponding load-bearing beam 40, the proportion of unidirectional fibers extending along the length direction X exceeds 70%. The fibers in the load-bearing beam 40 may include carbon fibers.

[0059] In this embodiment, the stiffness of the cover layer 80 is less than that of the load-bearing beam 40, making the cover layer 80 more easily deformable relative to the load-bearing beam 40. Therefore, a load-bearing beam 40 can be connected and transitioned using a cover layer 80 with relatively low stiffness. Exemplarily, the cover layer 80 and the load-bearing beam 40 can be bonded together using an adhesive. Exemplarily, the cover layer 80 can be a fabric. For example, the cover layer 80 can include fiberglass. Exemplarily, after the load-bearing beam 40 has been machined, the cover layer 80 can be laid at the end of the load-bearing beam 40, covering the mating bevel 41 and the mating end face 42, and fixing the cover layer 80 to the load-bearing beam 40.

[0060] In this embodiment, the adhesive 70 can fill the gap formed by the butt joint of two adjacent load-bearing beams 40. The adhesive 70 can bond two load-bearing beams 40 with a cover layer 80 and a reinforcing member 60 to form an integral structure, thereby achieving a butt joint connection between the two load-bearing beams 40. Exemplarily, the material of the adhesive 70 includes thermosetting adhesive or thermoplastic resin.

[0061] In the wind turbine blade 20 of this embodiment, a cover layer 80 is provided on the butt joint of the bearing beam 40. The cover layer 80 covers the butt joint inclined surface 41 and the butt joint end face 42 on the butt joint. The stiffness of the cover layer 80 is less than the stiffness of the bearing beam 40. The stiffness of the reinforcing member 60 is less than the stiffness of the bearing beam 40. The cover layer 80 can change the force transmission path. Therefore, the force transmission path between the two bearing beams 40 can include bearing beam 40-cover layer 80-adhesive body 70-reinforcing member 60-adhesive body 70-cover layer 80-bearing beam 40, which can help to disperse the force, reduce the stress concentration at the apex D2 of the bearing beam 40, reduce the possibility of cracking failure due to stress concentration between the butt joint end face 42 and the adhesive body 70, and improve the service life of the wind turbine blade 20.

[0062] In some feasible implementations, as shown in Figure 7, the mating end face 42 is also referred to as the thickened surface. The slope of the mating end face 42 is greater than the slope of the corresponding lap slope. The thickness H of the mating end face 42 is greater than or equal to 0.1 mm and less than or equal to 0.6 mm. For example, the thickness H of the mating end face 42 is greater than or equal to 0.2 mm and less than or equal to 0.4 mm.

[0063] In some feasible implementations, Figure 9 schematically shows a partial structure of the wind turbine blade 20. Referring to Figure 9, the cover layer 80 can be a single-layer structure, i.e., the cover layer 80 comprises a single layer 81. Each cover layer 80 is offset from the edge corresponding to the mating end face 42. The cover layer 80 has a protruding portion 801 extending beyond the mating end face 42 along the length direction X. The lengths of the protruding portions 801 are different.

[0064] The staggered arrangement of the edges of each cover layer 80 and the mating end face 42 helps to reduce the possibility of stress concentration in the edge area of ​​the cover layer 80 and improves the load-bearing capacity of the cover layer 80.

[0065] Of the two protruding portions 801 at the mating end face 42 of the cover layer 80, the length of the protruding portion 801 closer to the reinforcing member 60 is greater than the length of the protruding portion 801 farther from the reinforcing member 60. In the longitudinal direction X of the wind turbine blade 20, the stiffness of the cover layer 80 at the protruding portion 801 can gradually decrease, i.e., the change is slow rather than abrupt, which helps to further reduce the possibility of stress concentration at the edge of the cover layer 80.

[0066] In some examples, the lengths of the extended portion 801 in the vertical direction shown in Figure 9 are 80 mm and 110 mm, respectively.

[0067] In some examples, the cover layer 80 can be a single-layer structure. The thickness of the cover layer 80 can be from 0.5 mm to 0.9 mm.

[0068] In some feasible implementations, Figure 10 schematically shows a partial structure of the blade module 50. Referring to Figure 10, the cover layer 80 may include multiple layers 81. The multiple layers 81 are stacked along the thickness direction of the cover layer 80. The connection strength and load-bearing capacity of the cover layer 80, including multiple layers 81, are improved.

[0069] Multiple layers 81 are sequentially laid on the load-bearing beam 40 to form a cover layer 80. In some examples, the multiple layers 81 may be fixedly connected to the load-bearing beam 40 using an adhesive. In some examples, each layer 81 may be a fabric layer. Each layer 81 may include glass fiber. The thickness of each layer 81 may be the same.

[0070] In some examples, the thickness of layer 81 can be from 0.43 mm to 0.55 mm.

[0071] In some examples, the edges of each layer 81 corresponding to the mating end face 42 are staggered to reduce the possibility of stress concentration in the edge region of the cover layer 80, thereby improving the load-bearing capacity of the cover layer 80. Each layer 81 has a protruding portion 801 extending beyond the mating end face 42 along the length direction X. The lengths of the protruding portions 801 are different.

[0072] For example, in any two adjacent layers 81, the length of the protruding portion 801 closer to the reinforcing member 60 is greater than the length of the protruding portion 801 farther from the reinforcing member 60. In the longitudinal direction X of the wind turbine blade 20, the stiffness of the cover layer 80 at the position of the protruding portion 801 can gradually decrease, that is, the change is slow rather than abrupt, which helps to further reduce the possibility of stress concentration at the edge of the cover layer 80.

[0073] For example, the cover layer 80 includes two layers 81. At positions corresponding to the mating end face 42, four layers 81 are stacked on top of each other. The lengths of the protruding portions 801 of the four layers 81 are different. From the vertical direction shown in FIG10, the lengths of the protruding portions 801 increase sequentially; that is, the closer to the reinforcing member 60, the longer the protruding portion 801. For example, from the vertical direction shown in FIG10, the lengths of the protruding portions 801 are 30 mm, 60 mm, 90 mm, and 120 mm, respectively.

[0074] In some feasible implementations, referring to Figure 9, in two adjacent blade modules 50, the overhang 801 of one blade module 50 overlaps the cover layer 80 of the other blade module 50. The overhang 801 covers the gap formed by the mating of two adjacent load-bearing beams 40.

[0075] The extended portion 801 of the cover layer 80 can cooperate with the reinforcing member 60 to connect the two load-bearing beams 40, thereby improving the connection strength and load-bearing capacity of the two load-bearing beams 40. Simultaneously, the force transmission path between the two load-bearing beams 40 can also include load-bearing beam 40-cover layer 80-adhesive 70-cover layer 80-load-bearing beam 40, which increases the number of force transmission paths, helps disperse forces, and reduces the possibility of stress concentration in the load-bearing beams 40.

[0076] In some possible implementations, as shown in Figure 9, the reinforcement 60 covers the protruding portion 801. The protruding portion 801 of the covering layer 80 is located below the reinforcement 60. The reinforcement 60 can protect the protruding portion 801.

[0077] The reinforcing member 60 can be a single-layer structure or a multi-layer structure. For example, the reinforcing member 60 can be a single-layer structure including one layer of fiberglass fabric, or a multi-layer structure including multiple layers of fiberglass fabric. For example, the proportion of fibers extending along the length direction X in the reinforcing member 60 is less than the proportion of fibers extending along the length direction X in the supporting beam 40. It should be noted that the fibers can extend and distribute in different directions; the proportion of fibers extending along the length direction X refers to the proportion of fibers extending along the length direction X to all fibers. For example, the reinforcing member 60 and the supporting beam 40 can be made of different materials.

[0078] In some feasible configurations, as shown in Figure 9, the cover layer 80 extends beyond the stiffener 60 along the length direction X. In the completed load-bearing beam 40, the stiffener 60 has cover layers 80 on both sides along the length direction X, which helps to ensure that a connection area is formed between the stiffener 60 as a whole and the cover layer 80, thereby improving the connection strength and load-bearing capacity between the cover layer 80 and the stiffener 60.

[0079] In some feasible implementations, the elastic modulus of the cover layer 80 is greater than or equal to 8 GPa and less than or equal to 20 GPa. The cover layer 80 and the load-bearing beam 40 can be made of different materials.

[0080] In some possible implementations, FIG11 schematically shows a partial structure of the cover layer 80. Referring to FIG11, the cover layer 80 includes a first fiber 802 and a second fiber 803. The first fiber 802 extends along a first direction Y1. The second fiber 803 extends along a second direction Y2. The first direction Y1 forms an angle of 30° to 60° with the length direction X. The second direction Y2 forms an angle of 30° to 60° with the length direction X.

[0081] In some examples, the angle between the first direction Y1 and the second direction Y2 is 90°. The angle between the first direction Y1 and the length direction X is 45°. The angle between the second direction Y2 and the length direction X is 45°.

[0082] In this embodiment, the process of setting the cover layer 80 on the surface of the load-bearing beam 40 can be performed using a vacuum-assisted injection molding process. After the cover layer 80 is laid on the load-bearing beam 40, molten adhesive resin is impregnated into the cover layer 80 using a vacuum-assisted injection molding process. After the adhesive resin cures, the cover layer 80 is fixedly connected to the load-bearing beam 40.

[0083] The process of applying the cover layer 80 to the surface of the load-bearing beam 40 can also be performed using a hand lay-up process. After the cover layer 80 is laid on the load-bearing beam 40, adhesive is applied to the cover layer 80 using a hand lay-up process. After the adhesive has cured, the cover layer 80 is fixedly attached to the load-bearing beam 40.

[0084] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A wind turbine blade, characterized in that, include: Two or more blade modules are spliced ​​together along the length of the wind turbine blade. Each blade module includes a load-bearing beam and a cover layer. The load-bearing beam includes a connected docking ramp and a docking end face. The cover layer covers the docking ramp and the docking end face. The stiffness of the cover layer is less than the stiffness of the load-bearing beam. Any two adjacent blade modules are docked together, and the docking ramps overlap each other. A reinforcing member covers the gap formed by the butt joint of two adjacent load-bearing beams, and the reinforcing member connects two adjacent load-bearing beams. The stiffness of the reinforcing member is less than the stiffness of the load-bearing beam. The adhesive is used to bond the cover layer to the mating slope of the two load-bearing beams, as well as the reinforcement and the cover layer.

2. The wind turbine blade according to claim 1, characterized in that, The cover layer includes multiple layers, which are stacked along the thickness direction of the cover layer.

3. The wind turbine blade according to claim 2, characterized in that, The edges of each layer corresponding to the mating end face are staggered, and each layer has a protruding portion that extends beyond the mating end face along the length direction, and the lengths of the protruding portions are different.

4. The wind turbine blade according to claim 1, characterized in that, The cover layer is a single-layer structure, and each cover layer is staggered at the edge corresponding to the mating end face. The cover layer has a protruding part that extends beyond the mating end face along the length direction, and the length of each protruding part is different.

5. The wind turbine blade according to claim 3 or 4, characterized in that, In two adjacent blade modules, the overhang in one blade module overlaps the cover layer of the other blade module, and the overhang covers the gap formed by the butt joint of the two adjacent load-bearing beams.

6. The wind turbine blade according to any one of claims 3 to 5, characterized in that, The reinforcing member covers the extended portion.

7. The wind turbine blade according to any one of claims 3 to 6, characterized in that, The length of the protruding portion near the reinforcing member is greater than the length of the protruding portion away from the reinforcing member.

8. The wind turbine blade according to any one of claims 1 to 7, characterized in that, Along the length direction, the covering layer extends beyond the reinforcement.

9. The wind turbine blade according to any one of claims 1 to 8, characterized in that, The elastic modulus of the covering layer is greater than or equal to 8 GPa and less than or equal to 20 GPa.

10. The wind turbine blade according to any one of claims 1 to 9, characterized in that, The covering layer includes a first fiber and a second fiber, the first fiber extending along a first direction and the second fiber extending along a second direction, the first direction and the length direction forming an angle of 30° to 60°, and the second direction and the length direction forming an angle of 30° to 60°.

11. The wind turbine blade according to any one of claims 1 to 10, characterized in that, The adhesive material includes thermosetting adhesives or thermoplastic resins.

12. The wind turbine blade according to any one of claims 1 to 11, characterized in that, The reinforcing element includes glass fiber fabric.

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