Method for repairing pultrusion main beam of wind power blade and pultrusion main beam

Abstract

The invention relates to the field of wind power blades, and discloses a repairing method for a wind power blade pultrusion main beam and the pultrusion main beam, and the repairing method for the wind power blade pultrusion main beam comprises the steps that a main beam middleware of a wind power blade pultrusion main beam filling splicing piece assembly is obtained; and a reinforcing layer with the trend of gradually shrinking from the two ends in the stretching direction of the pultrusion main beam to the middle is laid to the main beam middleware in the stretching direction of the pultrusion main beam, the splicing piece assembly is completely covered, and a main beam repairing piece is obtained. The method is used for solving the problem that the strength is reduced after repairing, the reinforcing layer with the gradually-shrinking tendency at the two ends in the stretching direction of the pultrusion main beam is repaired on the splicing piece assembly, the end stress concentration of the repairing area in the stretching direction of the pultrusion main beam is reduced, the reinforcing layer with the gradually-shrinking end can release the end stress, and the repairing strength is improved.

Description

Technical Field

[0001] The present application belongs to the field of wind turbine blades, and in particular relates to a repair method for a pultruded main beam of a wind turbine blade and a pultruded main beam. Background Art

[0002] The pultruded main beam of a wind turbine blade is usually composed of multiple pultruded parts, which are arranged in a certain direction to form a pultruded sheet layer, thereby forming a main beam structure. The pultruded parts usually have a trapezoidal cross-section, and a guide channel is formed between two adjacent pultruded parts. This structure not only improves the structural strength of the main beam, but also enhances the bending and shear resistance of the wind turbine blade.

[0003] During the manufacturing process, the pultruded main beam may cause dry yarn defects due to poor infusion or damage due to transportation, and the pultruded main beam needs to be partially repaired. The existing repair methods cannot guarantee the strength and other performance of the pultruded main beam. Summary of the invention

[0004] The embodiments of the present application provide a repair method and a pultruded main beam of a wind turbine blade, which can ensure the strength of the pultruded main beam after repair.

[0005] In the first aspect, an embodiment of the present application provides a method for repairing a pultruded main beam of a wind turbine blade, comprising: obtaining a main beam middle piece of the wind turbine blade pultruded main beam filled with a splicing piece assembly; laying a reinforcement layer having a gradually shrinking trend toward the middle at both ends along the span of the pultruded main beam to the main beam middle piece along the span of the pultruded main beam, and completely covering the splicing piece assembly to obtain a main beam repair piece.

[0006] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, the reinforcing layer having a trend of gradually shrinking toward the middle along the two ends of the pultruded main beam in the span direction is laid to the main beam middle piece along the span direction of the pultruded main beam, and completely covers the splicing piece assembly, including: laying the first guide layer in the reinforcing layer to the main beam middle piece along the span direction of the pultruded main beam, and completely covering the splicing piece assembly; laying the reinforcing layer having a trend of gradually shrinking toward the middle along the two ends of the pultruded main beam in the reinforcing layer to the first guide layer along the span direction of the pultruded main beam, and covering the splicing piece assembly; laying the second guide layer in the reinforcing layer to the reinforcing layer along the span direction of the pultruded main beam, and connected to the first guide layer on both sides along the span direction of the pultruded main beam.

[0007] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, the reinforcing layer in the reinforcing layer having a trend of gradually shrinking toward the middle at both ends along the span direction of the pultruded main beam is laid along the span direction of the pultruded main beam to the first guide layer, and covers the splicing piece assembly, including: stacking multiple layers of uniaxial fiber layers along the thickness direction of the pultruded main beam, and arranging the multiple layers of uniaxial fiber layers along both ends along the span direction of the pultruded main beam with a trend of gradually shrinking toward the middle, to obtain the reinforcing layer in the reinforcing layer; laying the reinforcing layer along the span direction of the pultruded main beam to the first guide layer, and covering the splicing piece assembly.

[0008] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, the method of obtaining a main beam middle piece for filling the pultruded main beam of a wind turbine blade with a splicing piece assembly comprises: obtaining a defective groove having an increasing opening trend at both ends along the span direction of the pultruded main beam at a defective position of the wind turbine blade; and filling the splicing piece assembly into the defective groove to obtain the main beam middle piece.

[0009] According to the repair method for the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, a defective groove having an opening increasing trend at both ends along the span direction of the pultruded main beam is obtained at the defective position of the pultruded main beam of the wind turbine blade, comprising: cutting off at least one pultruded component at the defective position of the pultruded main beam of the wind turbine blade to remove the defective structure; and processing the cross-sectional surface of the pultruded component to obtain a defective groove having an opening increasing trend at both ends along the span direction of the pultruded main beam.

[0010] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, at least one pultruded component at a defective position of the pultruded main beam of the wind turbine blade is cut off to remove the defective structure, comprising: at the defective position of the pultruded main beam of the wind turbine blade, at least two pultruded components along the thickness direction of the pultruded main beam are respectively staggered and cut off along the span direction of the pultruded main beam to remove the defective structure.

[0011] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, at least one pultruded component at a defective position of the pultruded main beam of the wind turbine blade is cut off to remove the defective structure, including: cutting off the pultruded plate in at least one pultruded component at the defective position of the pultruded main beam of the wind turbine blade; cutting off the guide fiber layer in the pultruded component to remove the defective structure.

[0012] According to the repair method of the pultruded main beam of a wind turbine blade provided in an embodiment of the present application, the splicing piece assembly is filled into the defective groove to obtain a main beam middle piece, comprising: laying the third guide layer in the splicing piece assembly into the defective groove; laying the sheet group in the splicing piece assembly into the third guide layer to fill the defective groove to obtain the main beam middle piece.

[0013] According to the repair method of the wind turbine blade pultruded main beam provided by the embodiment of the present application, the sheet group in the splicing sheet assembly is laid on the third guide layer to fill the defective groove to obtain the main beam middle piece, including: laying the first sheet in the splicing sheet assembly on the third guide layer;

[0014] The fourth guide layer in the splicing piece assembly is laid on the first sheet; the second sheet in the splicing piece assembly is laid on the fourth guide layer to fill the defective groove and obtain the main beam middle piece.

[0015] In the second aspect, an embodiment of the present application also provides a pultruded main beam, comprising: a pultruded component stacked along the thickness direction of the pultruded main beam; a splicing sheet component arranged in the pultruded component; a reinforcement layer completely covering the splicing sheet assembly, and the reinforcement layer includes two ends along the span direction of the pultruded main beam that have a trend of gradually narrowing toward the middle.

[0016] According to the pultruded main beam of the embodiment of the present application, the reinforcement layer includes a first guide layer, a reinforcement layer and a second guide layer which are stacked in sequence along the thickness direction of the pultruded main beam, and the second guide layer covers both ends of the reinforcement layer along the span direction of the pultruded main beam and is connected to the first guide layer.

[0017] According to the pultruded main beam of the embodiment of the present application, the reinforcement layer includes a plurality of uniaxial fiber layers stacked along the thickness direction of the pultruded main beam, and the plurality of uniaxial fiber layers include inclined surfaces that gradually narrow toward the middle at both ends along the span direction of the pultruded main beam.

[0018] According to the pultruded main beam of the embodiment of the present application, the pultruded component includes a defect groove along the thickness direction of the pultruded main beam, the splicing piece component is arranged in the defect groove, and the defect groove includes a side wall with an opening increasing trend along the span direction of the pultruded main beam.

[0019] According to the pultruded main beam of the embodiment of the present application, the side wall of the defect groove includes a first wall segment and a second wall segment along the thickness direction of the pultruded main beam, and the first wall segment and the second wall segment are staggered along the span direction of the pultruded main beam.

[0020] According to the pultruded main beam of the embodiment of the present application, the splicing sheet assembly includes a third guide layer and a sheet group stacked along the thickness direction of the pultruded main beam, the third guide layer is arranged between the sheet group and the pultruded assembly, and the sheet group includes sheets stacked along the thickness direction of the pultruded main beam and a fourth guide layer arranged between the sheet layers.

[0021] The wind turbine blade pultruded main beam repair method and pultruded main beam of the embodiment of the present application are repaired on the splicing piece assembly by reinforcing layers with a gradual shrinkage trend at both ends of the pultruded main beam along the span direction, thereby reducing the stress concentration at the ends of the repair area along the span direction of the pultruded main beam. The gradually shrinking reinforcing layers at the ends can release the end stress and improve the repair strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 A schematic flow chart of a method for repairing a pultruded main beam of a wind turbine blade provided in some embodiments of the present application;

[0024] Figure 2 A cross-sectional view of a main beam middle member provided for some embodiments of the present application;

[0025] Figure 3 A cross-sectional view of a main beam repair part provided for some embodiments of the present application;

[0026] Figure 4 A schematic diagram of the layer structure of a reinforcement layer provided in some embodiments of the present application;

[0027] Figure 5 A partial stereoscopic view of a pultruded main beam of a wind turbine blade provided in some embodiments of the present application;

[0028] Figure 6 A partial cross-sectional view of a pultruded main beam of a wind turbine blade provided in some embodiments of the present application;

[0029] Figure 7 A cross-sectional view of a main beam repair part provided for other embodiments of the present application;

[0030] Figure 8 for Figure 7 Section view along AA direction;

[0031] Fig. 9 A partial stereoscopic view of a pultruded main beam of a wind turbine blade provided in some other embodiments of the present application;

[0032] Fig.10 A partial stereoscopic view of a pultruded main beam of a wind turbine blade provided in some other embodiments of the present application;

[0033] Fig.11 A partial cross-sectional schematic diagram of a pultruded main beam of a wind turbine blade provided in some other embodiments of the present application;

[0034] Fig.12A cross-sectional view of a main beam middle piece provided for some other embodiments of the present application;

[0035] Fig.13 for Fig.12 Cross-sectional view along BB direction.

[0036] Reference numerals:

[0037] 1: Main beam middle piece; 10: Pultruded main beam; 11: Pultruded assembly; 12: Pultruded plate; 13: Guide fiber layer; 14: First spacing; 2: Main beam repair piece;

[0038] 100: splicing sheet assembly; 110: sheet group; 111: third guide layer; 101: first sheet; 102: fourth guide layer; 103: second sheet; X: span direction of pultruded main beam; Y: chord direction of pultruded main beam; Z: thickness direction of pultruded main beam; 200: reinforcement layer; 203: first guide layer; 202: reinforcement layer; 201: second guide layer; 300: defect groove; 301: first wall segment; 302: second wall segment; 303: second spacing. DETAILED DESCRIPTION

[0039] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0040] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0041] The main beam of a wind turbine blade is an important component of the wind turbine blade. It mainly plays a supporting and load-bearing role. Its performance directly affects the strength, stiffness and stability of the wind turbine blade. At present, the main beam forming processes of wind turbine blades mainly include vacuum infusion forming process, prepreg forming process, pultrusion forming process, etc. Among them, the pultrusion forming process has a higher fault tolerance, resource utilization rate, fiber content and stronger structural performance compared with other processes. It has gradually developed into the mainstream forming process of the main beam of wind turbine blades.

[0042] Since the pultruded main beam has a high fiber content and a high specific modulus, it is easy to be damaged during the production or transportation of the pultruded main beam, for example, interlayer defects of the pultruded main beam caused by poor resin impregnation, namely dry yarn defects.

[0043] When repairing the damaged area of ​​the pultruded main beam, it is necessary to remove the structure of the damaged area of ​​the pultruded main beam, and fill the pit formed after the removal, and fill the pit with the pultruded sheet. However, the existing repair method cannot meet the strength of the local area of ​​the pultruded main beam after filling, thereby affecting the strength, shear resistance, bending resistance, etc. of the entire pultruded main beam.

[0044] In order to ensure the strength and other properties of the repaired pultruded main beam 10, the embodiment of the present application provides a repair method for the pultruded main beam 10 of a wind turbine blade, and the upper surface of the pultruded sheet used for repair is completely covered with a reinforcing layer 200, which can stabilize the pultruded sheet on the one hand, and connect the truncation formed when the damaged structure of the pultruded main beam 10 is removed on the other hand, thereby improving the integrity of the main beam. Completely covering the pultruded sheet can reduce the number of ends, thereby reducing the stress concentration position.

[0045] In order to further reduce the stress concentration problem at the end of the reinforcement layer 200, the end of the reinforcement layer 200 is tapered to release the end stress at the junction of the reinforcement layer 200 and the pultruded main beam 10, reduce stress concentration and stress accumulation, improve the strength of the repair area of ​​the pultruded main beam 10, and ensure the overall strength, shear resistance, bending resistance, etc. of the pultruded main beam 10.

[0046] The repair method of the wind turbine blade pultruded main beam 10 disclosed in the embodiment of the present application can be used for, but not limited to, any structural damage caused after the pultruded main beam 10 is formed, before transportation, after transportation, and during installation. The pultruded main beam 10 in the embodiment of the present application can be the main beam of a short blade, a long blade, a fixed pitch blade, a variable pitch blade, a glass fiber reinforced composite blade, a carbon fiber reinforced composite blade, and the like.

[0047] Figure 1 A schematic flow chart of a repair method for a wind turbine blade pultruded main beam 10 provided in some embodiments of the present application; Figure 2A cross-sectional view of a main beam middle member 1 provided for some embodiments of the present application; Figure 3 A cross-sectional view of a main beam repair component 2 provided in some embodiments of the present application.

[0048] like Figures 1 to 3 As shown, some embodiments of the present application provide a method for repairing a pultruded main beam 10 of a wind turbine blade, comprising steps S1 and S2.

[0049] S1: Obtaining the main beam middle piece 1 of the wind turbine blade pultruded main beam 10 filled with the splicing piece assembly 100.

[0050] S2: Lay the reinforcing layer 200 with a trend of gradually shrinking toward the middle at both ends of the pultruded main beam along the span direction X to the main beam middle piece 1 along the span direction X of the pultruded main beam, and completely cover the splicing piece assembly 100 to obtain the main beam repair part 2.

[0051] The splicing sheet assembly 100 is a plate-type structure made of the same or matching material as the material of the wind turbine blade pultruded main beam 10. The splicing sheet assembly 100 can be an integral plate structure, or a plate structure formed by a combination of multiple structures, for example, a plate structure formed by stacking up and down or splicing left and right. The material of the splicing sheet assembly 100 can include glass fiber reinforced composite materials or carbon fiber reinforced composite materials, which are formed by resin impregnation and curing. Its shape is based on the shape of the position to be filled, and its cross-section can be a rectangular, trapezoidal, or other structures.

[0052] The splicing piece assembly 100 is filled in the pultruded main beam 10 of the wind turbine blade, so that there is no obvious gap between the pultruded main beam 10 and the splicing piece assembly 100, and the pultruded main beam 10 and the splicing piece assembly 100 are in close contact or connection to form a whole. After the splicing piece assembly 100 is filled into the pultruded main beam 10, the surface of the splicing piece assembly 100 and the pultruded main beam 10 can be flush, or the splicing piece assembly 100 is lower than the surface of the pultruded main beam 10 in the thickness direction. In an optional embodiment of the present application, the splicing piece assembly 100 is flush with the surface of the pultruded main beam 10, which can ensure the flatness and smoothness of the surface of the main beam middle piece 1 and meet the strength requirements of the pultruded main beam 10.

[0053] The main beam middle piece 1 is an intermediate structure in the repair process of the pultruded main beam 10, and can only be used as a qualified pultruded main beam 10 after subsequent processing. For example, by laying a reinforcement layer 200 on the main beam middle piece 1, a main beam repair piece 2 is formed. The main beam middle piece 1 is obtained by filling the splicing piece assembly 100 in the pultruded main beam 10 of the wind turbine blade. The pultruded main beam 10 and the splicing piece assembly 100 can be connected by adhesive or resin curing to ensure the connection strength and stability between the pultruded main beam 10 and the splicing piece assembly 100.

[0054] The reinforcing layer 200 is a sheet structure formed of a fiber material with a certain thickness, so as to connect the surface of the cut-off area of ​​the pultruded main beam 10, so as to improve the integrity of the main beam middle piece 1 and improve the strength of the main beam middle piece 1. The reinforcing layer 200 can be a single-layer structure or a multi-layer composite structure, for example, one or more of a uniaxial fiber cloth or a biaxial fiber cloth. The reinforcing layer 200 is laid to the repair position of the main beam middle piece 1, and the reinforcing layer 200 and the main beam middle piece 1 can be bonded by adhesive or connected by resin nails, or formed into a stable whole by resin infusion and curing. In addition, the reinforcing layer 200 can be one or more, for example, multiple reinforcing layers 200 are continuously laid along the surface of the main beam middle piece 1. The thickness of the multiple reinforcing layers 200 can be the same or different, and the constituent materials of the multiple reinforcing layers 200 can be the same or different. For example, the thickness of the multiple reinforcing layers 200 is set in a gradient transition with thin sides and thick middle.

[0055] The span direction X of the pultruded main beam refers to the length direction of the pultruded main beam 10. The length direction of the pultruded main beam 10 is consistent with the length direction of the splicing sheet assembly 100. The reinforcing layer 200 is laid to the main beam middle piece 1 along the span direction X of the pultruded main beam. The length direction of the reinforcing layer 200 can be consistent with the span direction X of the pultruded main beam, or the fiber orientation of the reinforcing layer 200 is consistent with the span direction X of the pultruded main beam, so that the fiber orientation of the reinforcing layer 200 is consistent with the fiber orientation of the pultruded main beam 10. Multiple reinforcing layers 200 are laid to the main beam middle piece 1 along the span direction X of the pultruded main beam.

[0056] The two ends of the reinforcing layer 200 along the span direction X of the pultruded main beam refer to the two opposite end sides of the reinforcing layer 200 along the span direction X of the pultruded main beam. The reinforcing layer 200 is a sheet structure and includes two sets of opposite ends, one pair of which is arranged oppositely along the span direction X of the pultruded main beam, and the other pair is arranged oppositely along the chord direction Y of the pultruded main beam. The chord direction Y of the pultruded main beam is the width direction of the pultruded main beam 10, which is perpendicular to the span direction X of the pultruded main beam.

[0057] The two ends of the reinforcing layer 200 along the span direction X of the pultruded main beam have a tendency to gradually shrink toward the middle. The middle of the reinforcing layer 200 refers to the centerline position along the span direction X of the pultruded main beam. The ends tend to gradually shrink toward the middle, so that the ends of the reinforcing layer 200 are inclined, and the inclined surface makes the length of the reinforcing layer 200 away from the middle piece 1 of the main beam shorter than the length close to the middle piece 1 of the main beam.

[0058] The reinforcing layer 200 completely covers the splicing piece assembly 100 to form the main beam repair part 2, so that the orthographic projection of the reinforcing layer 200 on the main beam middle part 1 covers the orthographic projection of the splicing piece assembly 100 on the main beam middle part 1. Among them, the area of ​​the reinforcing layer 200 is larger than the area of ​​the splicing piece assembly 100. The reinforcing layer 200 can protect the splicing piece assembly 100, and at the same time, there is an overlap between the reinforcing layer 200 and the pultruded main beam 10. The peeling stress of the end of the reinforcing layer 200 can be reduced by about 25% compared with the method without the reinforcing layer 200, and the shear stress can be reduced by about 55% compared with the method without the reinforcing layer 200.

[0059] The reinforcing layer 200 is covered in the area of ​​the pultruded main beam 10 filled with the splicing sheet assembly 100 to improve the overall connectivity of the pultruded main beam 10. The two ends of the reinforcing layer 200 have a trend of tapering toward the middle to reduce the peeling stress and end stress concentration, thereby improving the strength, bending resistance, shear resistance and other properties of the main beam repair part 2.

[0060] Figure 4 Schematic diagram of the layer structure of the reinforcement layer 200 provided in some embodiments of the present application.

[0061] like Figure 4 As shown, in one embodiment of the present application, the above-mentioned step S2: laying the reinforcement layer 200 having a gradually shrinking trend toward the middle at both ends of the pultruded main beam along the span direction X to the main beam middle piece 1 along the span direction X of the pultruded main beam, and completely covering the splicing piece assembly 100, specifically includes steps S21 to S23.

[0062] S21: Lay the first guide layer 203 in the reinforcement layer 200 to the main beam middle piece 1 along the span direction X of the pultruded main beam, and completely cover the splicing sheet assembly 100 .

[0063] S22: Lay the reinforcing layer 202 with a trend of gradually shrinking toward the middle at both ends of the reinforcing layer 200 along the span direction X of the pultruded main beam to the first guide layer 203 along the span direction X of the pultruded main beam, and cover the splicing sheet assembly 100 .

[0064] S23: Lay the second guide layer 201 in the reinforcement layer 200 to the reinforcement layer 202 along the span direction X of the pultruded main beam, and connect it to the first guide layer 203 on both sides along the span direction X of the pultruded main beam.

[0065] The first guide layer 203 is a sheet structure of fiber material with a certain thickness, which has strong guide properties and can be used to improve the penetration effect of resin and other perfusion liquids. The first guide layer 203 can be a single-layer or multi-layer fiber structure. For example, the first guide layer 203 can be a biaxial fiber fabric with a surface weight of not less than 600g / m 2 .

[0066] The reinforcing layer 202 is a sheet structure of fiber material with a certain thickness, which has high axial strength and can withstand loads in a specific direction. The reinforcing layer 202 can be a single-layer or multi-layer fiber structure. For example, the reinforcing layer 202 can be a uniaxial fiber fabric. Due to the unidirectional arrangement of the fibers, the uniaxial fiber fabric can more accurately reinforce the structure in a directional manner. It can better resist loads and reduce the risk of deformation and damage to the main beam repair part 2. The uniaxial fiber fabric can be a low-thickness fabric with a surface weight of about 650g / m 2 When the reinforcing layer 202 is a multi-layer uniaxial fiber fabric, in order to reduce the stress concentration caused by the thickness difference, the multi-layer uniaxial fiber fabric can be increased or decreased according to the actual modulus requirements.

[0067] The second guide layer 201 is a sheet structure of fiber material with a certain thickness, which has strong guide characteristics and stress dispersion ability, and can improve the penetration effect and stress uniformity of the resin and other perfusion liquids. The second guide layer 201 can be a single-layer or multi-layer fiber structure. For example, the second guide layer 201 can be a biaxial fiber fabric with a surface weight of not less than 600g / m 2 .

[0068] The second guide layer 201 is connected to the first guide layer 203 on both sides along the span direction X of the pultruded main beam, so that the second guide layer 201 and the first guide layer 203 cover the reinforcement layer 202 along the span direction X of the pultruded main beam, so that the end of the reinforcement layer 202 along the span direction X of the pultruded main beam is covered by the second guide layer 201 or the first guide layer 203. The lengths of the first guide layer 203 and the second guide layer 201 along the span direction X of the pultruded main beam are both greater than the length of the reinforcement layer 202. The connection between the first guide layer 203 and the second guide layer 201 can be a direct connection or an indirect connection, for example, the second guide layer 201 is connected to the surface of the main beam middle piece 1, and the first guide layer 203 is connected to the surface of the main beam middle piece 1, so as to achieve an indirect connection between the first guide layer 203 and the second guide layer 201. Or, for another example, the second guide layer 201 extends from both ends of the laminating reinforcement layer 202 to the first guide layer 203 and is directly connected to the first guide layer 203 .

[0069] The first guide layer 203 is disposed between the reinforcement layer 202 and the splicing sheet assembly 100 to ensure dimensional deviation and bonding interface performance. The reinforcement layer 202 improves the load bearing capacity of the reinforcement layer 200. The second guide layer 201 covers the end of the reinforcement layer 202 to reduce the peeling stress of the reinforcement layer 202 and disperse the force.

[0070] In other embodiments of the present application, the first guide layer 203 , the reinforcement layer 202 , and the second guide layer 201 may be stacked and laid to form a reinforcement layer 200 , and then the reinforcement layer 200 may be laid to the main beam middle member 1 .

[0071] Furthermore, in another embodiment of the present application, step S2 includes steps S22 and S23, wherein the second guide layer 201 is connected to the main beam middle piece 1.

[0072] Continue to refer Figure 4 In some optional embodiments of the present application, the above-mentioned step S22: laying the reinforcing layer 202 having a trend of gradually shrinking toward the middle at both ends of the reinforcement layer 200 along the span direction X of the pultruded main beam along the span direction X of the pultruded main beam to the first guide layer 203, and covering the splicing sheet assembly 100, includes steps S221 and S222.

[0073] S221: stacking multiple uniaxial fiber layers along the thickness direction of the pultruded main beam 10, and arranging the multiple uniaxial fiber layers along both ends of the pultruded main beam in a gradually shrinking trend toward the middle in the span direction X to obtain the reinforcing layer 202 in the reinforcement layer 200.

[0074] S222 : Lay the reinforcement layer 202 along the span direction X of the pultruded main beam to the first guide layer 203 , and cover the splicing sheet assembly 100 .

[0075] The thickness direction of the pultruded main beam 10 is perpendicular to the span direction X of the pultruded main beam. The uniaxial fiber layer is obtained by cutting the above-mentioned uniaxial fiber fabric into appropriate sizes. The lengths of the multiple uniaxial fiber layers along the span direction X of the pultruded main beam are different. From the first guide layer 203 to the second guide layer 201, the length of the uniaxial fiber layer along the span direction X of the pultruded main beam is continuously shortened, thereby forming a gradual shrinking trend toward the middle.

[0076] In the embodiment of the present application, the length of the uniaxial fiber layer with the shortest length along the span direction X of the pultruded main beam in the reinforcement layer 202 may be greater than the length of the splicing sheet assembly 100 .

[0077] The strength of the reinforcing layer 202 is improved by arranging multiple uniaxial fiber layers, thereby improving the load resistance of the main beam repair part 2. The multiple uniaxial fiber layers are arranged along the two ends of the pultruded main beam in the direction X and gradually shrink toward the middle, thereby reducing the thickness mutation of the multiple uniaxial fiber layers and reducing the stress concentration at the end.

[0078] In other embodiments of the present application, multiple uniaxial fiber layers may be laid sequentially on the main beam middle piece 1 .

[0079] Figure 5 A partial stereoscopic view of a wind turbine blade pultruded main beam 10 provided in some embodiments of the present application; Figure 6 A partial cross-sectional view of a wind turbine blade pultruded main beam 10 provided in some embodiments of the present application; Figure 7 A cross-sectional view of a main beam repair member 2 provided for other embodiments of the present application; Figure 8 for Figure 7 Section view along AA.

[0080] like Figures 5 to 8 As shown, in some embodiments of the present application, the above step S1: obtaining the main beam middle piece 1 of the wind turbine blade pultruded main beam 10 filled with the splicing piece assembly 100 includes steps S11 and S12.

[0081] S11: At the defect position of the pultruded main beam 10 of the wind turbine blade, a defect groove 300 with an opening increasing trend at both ends along the span direction X of the pultruded main beam is obtained.

[0082] S12: Fill the defect groove 300 with the splicing piece assembly 100 to obtain the main beam middle piece 1.

[0083] The defective position refers to the area damaged by dry yarn defects or transport collisions, and the defective position is mainly formed on the upper and lower surfaces of the pultrusion main beam 10. The defective position can expand in one or more directions of the span direction, chord direction, and thickness direction of the pultrusion main beam 10.

[0084] The defective groove 300 is a concave structure formed by removing the structure at the defective position. The volume of the defective groove 300 is greater than the volume of the structure corresponding to the defective position. The defective groove 300 can be obtained by removing the structure at the defective position by a cutting tool, and can be obtained by cutting once or multiple times.

[0085] The pultruded main beam 10 is obtained by stacking a plurality of pultruded components 11. The pultruded components 11 are composite material plates manufactured by the pultrusion process, mainly including fibers and a resin matrix infiltrated between the fibers, such as glass fibers, carbon fibers and other materials with high strength and high modulus. The fibers can be arranged unidirectionally or approximately unidirectionally in the pultruded components 11. This makes the pultruded plate 12 have extremely high strength and rigidity in the fiber direction. For example, the tensile strength of the glass fiber pultruded component 11 in the fiber direction can reach hundreds of megapascals, which is much higher than that of traditional metal materials. The unidirectionally arranged fibers can effectively withstand the axial loads to which the pultruded component 11 is subjected during use, thereby improving the bearing capacity of the plate. The fiber content in the pultruded component 11 is relatively high, which can reach 60%-80%. The high fiber content makes the pultruded component 11 have excellent mechanical properties and dimensional stability. The resin matrix is ​​another important component of the pultruded plate 12, which bonds the fiber reinforcement materials together to form a whole. The resin matrix can include unsaturated polyester resin, vinyl ester resin, epoxy resin, etc.

[0086] like Figure 5 and Figure 6As shown, the pultruded component 11 is in the shape of a strip, the length direction of the pultruded component 11 is consistent with the span direction X of the pultruded main beam, and the width direction of the pultruded component 11 is consistent with the chord direction of the pultruded main beam 10. The defect groove 300 is formed on the pultruded component 11, and the structure at the defect position is removed in units of a single pultruded component 11, so that the width of the defect groove 300 along the chord direction of the pultruded main beam 10 is a multiple of the width of the pultruded component 11. The length of the defect groove 300 along the span direction of the pultruded main beam 10 is less than the length of the pultruded component 11.

[0087] The opening of the defective groove 300 along the span direction X of the pultruded main beam tends to increase, that is, the length of the side of the defective groove 300 facing away from the reinforcing layer 200 is shorter than the side close to the reinforcing layer 200. The side wall of the defective groove 300 along the span direction X of the pultruded main beam is an inclined surface, which can be a convex inclined surface, a concave inclined surface, a wavy inclined surface or a straight inclined surface. For example, the side wall of the defective groove 300 is a straight inclined surface, and the inclined surface angle range is between 1:100 and 1:200.

[0088] The splicing sheet assembly 100 is filled to the defective groove 300, such as Figure 7 and Figure 8 As shown, the end side of the splicing sheet component 100 matches the shape of the side wall of the defect groove 300. The thickness of the splicing sheet component 100 is a multiple of the thickness of the pultruded component 11.

[0089] By providing a defective groove 300 with an increasing trend on the pultruded main beam 10, the joint between the pultruded main beam 10 and the splicing sheet assembly 100 is made to fit in an inclined manner, so that there is no sudden change in stiffness at the joint, thereby reducing the end stress at the joint.

[0090] Fig. 9 A partial stereoscopic view of a wind turbine blade pultruded main beam 10 provided in some other embodiments of the present application; Fig.10 A partial stereoscopic view of a pultruded main beam 10 of a wind turbine blade provided in some other embodiments of the present application.

[0091] like Figure 5 , Fig. 9 and Fig.10 As shown, in a specific embodiment of the present application, step S11 in the above embodiment: obtaining a defective groove 300 with an increasing opening trend at both ends along the span direction X of the pultruded main beam 10 at the defect position of the wind turbine blade, includes steps S111 and S112.

[0092] S111: Cut off at least one pultruded component 11 at a defective position of the pultruded main beam 10 of the wind turbine blade to remove the defective structure.

[0093] S112: Process the cross-section of the pultruded component 11 to obtain defective grooves 300 with an increasing opening trend at both ends along the span direction X of the pultruded main beam.

[0094] At least one pultruded component 11 is cut off, and multiple pultruded components 11 can be cut off based on the range of the defect position to form defect grooves 300 of different sizes. For example, multiple pultruded components 11 along the chord direction Y of the pultruded main beam, and / or multiple pultruded components 11 along the thickness direction Z of the pultruded main beam are separated or cut off at the same time. Wherein, cutting refers to cutting along the cross section of a single pultruded component 11.

[0095] The defective structure is a pultruded component 11 that is damaged at a defective location.

[0096] A truncated pultruded component 11 will form two opposite truncated surfaces. The truncated surfaces of the pultruded component 11 are processed to make them smooth, burr-free, and reach a specified shape. For example, grinding, cutting, etc. For example, when the pultruded main beam 10 has multiple truncated surfaces, the multiple truncated surfaces are ground separately or simultaneously.

[0097] Fig.11 Schematic diagram of a partial cross section of a pultruded main beam 10 of a wind turbine blade provided in some other embodiments of the present application.

[0098] like Fig.10 and 11 As shown, in another specific embodiment of the present application, the above-mentioned step S111: cutting off at least one pultruded component 11 at the defective position of the pultruded main beam 10 of the wind turbine blade to remove the defective structure, includes: at the defective position of the pultruded main beam 10 of the wind turbine blade, at least two pultruded components 11 along the thickness direction of the pultruded main beam 10 are respectively cut off along the X-direction of the pultruded main beam span to remove the defective structure.

[0099] The misalignment along the span direction X of the pultruded main beam indicates that there is no continuity along a trend in the span direction X of the pultruded main beam. At least two pultruded components 11 are respectively misaligned and truncated along the span direction X of the pultruded main beam, indicating that there is a first spacing 14 between the cross-sections on one side of two adjacent pultruded components 11 along the span direction X of the pultruded main beam, and the first spacing 14 between the cross-sections on one side of different pultruded components 11 can be the same or different. For example, the length of the first spacing 14 is greater than 0.5 meters. There is a second spacing 303 between the cross-sections of the same layer, and the second spacing 303 of different layers is different. For example, the two pultruded components 11 at the defective position of the pultruded main beam 10 of the wind turbine blade are truncated, and the first layer of pultruded components 11 is placed above the second layer of pultruded components 11, and the second spacing 303 between the cross-sections of the first layer of pultruded components 11 is greater than the second spacing 303 between the cross-sections of the second layer of pultruded components 11.

[0100] By staggering and truncating the multi-layer pultruded components 11 along the X-direction of the pultruded main beam, it is convenient for layered processing to form independent processing units, reduce the uneven transition or gap between adjacent pultruded components 11, and reduce the formation of secondary defects during the resin infusion and curing process. In addition, the first spacing 14 formed by staggering facilitates the laying and overlapping of interlayer materials and improves the interlayer connection strength.

[0101] In addition, continue to refer to Figure 6 In an optional embodiment of the present application, the above step S111: cutting off at least one pultruded component 11 at a defective position of the pultruded main beam 10 of the wind turbine blade to remove the defective structure includes S1111 and S1112.

[0102] S1111: Cut off the pultruded plate 12 in at least one pultruded component 11 at the defective position of the pultruded main beam 10 of the wind turbine blade.

[0103] S1112: Cut off the guide fiber layer 13 in the pultruded component 11 to remove the defective structure.

[0104] The pultruded component 11 includes a stacked pultruded plate 12 and a guide fiber layer 13. The pultruded plate 12 can be preformed by stacking multiple layers of fiber cloth and resin curing. The guide fiber layer 13 can include a material with high strength and high modulus such as glass fiber and carbon fiber to improve the resin infusion and guide effect of the pultruded component 11.

[0105] For example, when only one pultruded component 11 of one layer is removed, the pultruded plate 12 of the layer and the guide fiber layer 13 below the pultruded plate 12 need to be cut off and removed to ensure the connection strength between the upper and lower adjacent pultruded components 11 during the subsequent resin infusion and curing.

[0106] Fig.12 A cross-sectional view of a main beam middle member 1 provided in some other embodiments of the present application; Fig.13 for Fig.12 Cross-sectional view along BB direction.

[0107] refer to Figure 7 , Fig.12 and Fig.13 The above step S12: filling the splicing piece assembly 100 into the defective groove 300 to obtain the main beam middle piece 1 includes steps S121 and S122.

[0108] S121 : Laying the third guide layer 111 in the splicing sheet assembly 100 to the defective groove 300 .

[0109] S122: Laying the sheet group 110 in the splicing sheet assembly 100 to the third guide layer 111 to fill the defective groove 300 and obtain the main beam middle piece 1.

[0110] The third guide layer 111 can have the same structure as the first guide layer 203, which is a sheet structure of fiber material with a certain thickness, has strong guide properties, and can be used to improve the penetration effect of resin and other perfusion liquids. The third guide layer 111 can be a single-layer or multi-layer fiber structure. For example, the third guide layer 111 can be a biaxial fiber fabric with a surface weight of not less than 600g / m 2 .

[0111] The third guide layer 111 is laid to the defective groove 300, which means that the third guide layer 111 is laid along the side wall and bottom of the defective groove 300. It can also be that one third guide layer 111 completely lays the defective groove 300, or it can be that multiple third guide layers 111 are laid continuously. Multiple third guide layers 111 can all be laid along the span direction X of the pultruded main beam, and multiple third guide layers 111 can have overlapping parts. The third guide layer 111 extends from the defective groove 300 at both ends along the span direction X of the pultruded main beam by a length of not less than 50 mm, and is adhered to the surface of the pultruded main beam 10. The third guide layer 111 can be bonded to the defective groove 300 by adhesive so that the third guide layer 111 is adhered to the defective groove 300.

[0112] The sheet group 110 is composed of one or more sheet groups 110, and the multiple sheets can be arranged horizontally or stacked up and down. The sheet can have the same structure as the pultruded plate 12, and is prefabricated by stacking multiple layers of fiber cloth and curing resin.

[0113] The sheet group 110 is laid to the third guide layer 111 to fill the defective groove 300. The thickness of the sheets in the sheet group 110 is consistent with the thickness of the pultruded plate 12 of the pultruded component 11. For example, when the groove depth of the curved groove is twice the thickness of the pultruded plate 12, two sheets are required in the depth direction. When the groove width of the defective groove 300 is twice the thickness of the pultruded plate 12, two sheets are required in the width direction. The length and shape of each sheet match the defective groove 300.

[0114] The penetration effect of subsequent resin infusion is improved by laying the third guide layer 111 in the defective groove 300. The sheet group 110 fills the defective groove 300 to make the surface of the main beam middle member 1 smoother and reduce the concentrated stress at the joint.

[0115] Continue to refer Fig.12 and Fig.13 In some specific embodiments of the present application, the above step S122: laying the sheet group 110 in the splicing sheet assembly 100 to the third guide layer 111 to fill the defective groove 300 to obtain the main beam middle piece 1, includes steps S1221 to S1223.

[0116] S1221 : Laying the first sheet 101 in the splicing sheet assembly 100 to the third guide layer 111 .

[0117] S1222 : Laying the fourth guide layer 102 in the splicing sheet assembly 100 onto the first sheet 101 .

[0118] S1223: Lay the second sheet 103 in the splicing sheet assembly 100 on the fourth guide layer 102 to fill the defective groove 300 and obtain the main beam middle piece 1.

[0119] The fourth guide layer 102 can have the same structure as the first guide layer 203, which is a sheet structure of fiber material with a certain thickness, has strong guide properties, and can be used to improve the penetration effect of resin and other perfusion liquids. The third guide layer 111 can be a single-layer or multi-layer fiber structure. For example, the third guide layer 111 can be a biaxial fiber fabric with a surface weight of not less than 600g / m 2 .

[0120] like Fig.11 As shown, the corresponding defective groove 300 has a groove depth of twice that of the pultruded component 11 along the thickness direction of the pultruded main beam 10, and the defective groove 300 includes a first groove formed on the first layer pultruded component 11 and a second groove formed on the second layer pultruded component 11, the first groove and the second groove are connected, and the side walls of the first groove and the second groove are displaced along the span direction of the pultruded main beam 10 to form a first spacing 14. The thickness of the first sheet 101 is equal to the thickness of the pultruded plate 12 in the first layer pultruded component 11, the first sheet 101 fills the first groove, and the fourth guide layer 102 is laid on the first sheet 101, completely covering the first sheet 101. The thickness of the second sheet 103 is equal to the thickness of the pultruded plate 12 in the second layer pultruded component 11, the second sheet 103 fills the second groove, and completely covers the first sheet 101 and the first spacing 14 formed by the dislocation.

[0121] The second sheet 103 is covered with a reinforcing layer 200, and both ends of the shortest uniaxial fiber layer in the reinforcement layer 202 of the reinforcing layer 200 along the span direction of the pultruded main beam 10 are at least 50 mm longer than the longest part of the second sheet 103. The first guide layer 203 in the reinforcing layer 200 covers the third guide layer 111.

[0122] The defect grooves 300 of multiple layers of thickness are laid out through multiple layers of sheets to reduce the probability of secondary defects and improve the repair effect. The fourth guide layer 102 is arranged between the sheet layers to improve the resin penetration effect and ensure the overall strength of the sheet group 110 and the connection strength between the sheet group 110 and the pultrusion assembly 11.

[0123] Continue to refer Figure 3The embodiment of the present application also provides a pultruded main beam 10, including: a pultruded component 11 stacked along the thickness direction Z of the pultruded main beam; a splicing piece component 100, which is arranged in the pultruded component 11; a reinforcement layer 200, which completely covers the splicing piece component 100, and the reinforcement layer 200 includes two ends that have a trend of gradually shrinking toward the middle along the span direction X of the pultruded main beam.

[0124] The reinforcing layer 200 is covered in the area of ​​the pultruded main beam 10 filled with the splicing sheet assembly 100 to improve the overall connectivity of the pultruded main beam 10. The two ends of the reinforcing layer 200 have a trend of tapering toward the middle to reduce the peeling stress and end stress concentration, thereby improving the strength, bending resistance, shear resistance and other properties of the main beam repair part 2.

[0125] Continue to refer Figure 4 In one embodiment of the present application, the reinforcement layer 200 includes a first guide layer 203, a reinforcement layer 202 and a second guide layer 201 which are stacked in sequence along the thickness direction Z of the pultruded main beam. The second guide layer 201 covers both ends of the reinforcement layer 202 along the span direction X of the pultruded main beam and is connected to the first guide layer 203.

[0126] The first guide layer 203 is disposed between the reinforcement layer 202 and the splicing sheet assembly 100 to ensure dimensional deviation and bonding interface performance. The reinforcement layer 202 improves the load bearing capacity of the reinforcement layer 200. The second guide layer 201 covers the end of the reinforcement layer 202 to reduce the peeling stress of the reinforcement layer 202 and disperse the force.

[0127] In another embodiment of the present application, the reinforcing layer 202 includes multiple uniaxial fiber layers stacked along the thickness direction Z of the pultruded main beam, and the multiple uniaxial fiber layers include inclined surfaces that gradually taper toward the middle at both ends along the span direction X of the pultruded main beam.

[0128] The strength of the reinforcing layer 202 is improved by arranging multiple uniaxial fiber layers, thereby improving the load resistance of the main beam repair part 2. The multiple uniaxial fiber layers are arranged along the two ends of the pultruded main beam in the direction X and gradually shrink toward the middle, thereby reducing the thickness mutation of the multiple uniaxial fiber layers and reducing the stress concentration at the end.

[0129] Continue to refer Figure 6 In other embodiments of the present application, the pultruded component 11 includes a defect groove 300 along the thickness direction Z of the pultruded main beam, the splicing sheet component 100 is arranged in the defect groove 300, and the defect groove 300 includes a side wall with an opening increasing trend along the span direction X of the pultruded main beam.

[0130] By providing a defective groove 300 with an increasing trend on the pultruded main beam 10, the joint between the pultruded main beam 10 and the splicing sheet assembly 100 is made to fit in an inclined manner, so that there is no sudden change in stiffness at the joint, thereby reducing the end stress at the joint.

[0131] Continue to refer Fig.11 In a specific embodiment of the present application, the side wall of the defect groove 300 includes a first wall segment 12 and a second wall segment 13 along the thickness direction Z of the pultruded main beam, and the first wall segment 301 and the second wall segment 302 are staggered along the span direction X of the pultruded main beam.

[0132] The first wall section 301 and the second wall section 302 are formed by staggering the multi-layer pultruded components 11 along the span direction X of the pultruded main beam, which is convenient for layered processing, forming an independent processing unit, reducing the uneven transition or gap between adjacent pultruded components 11, and reducing the formation of secondary defects during the resin infusion and curing process. In addition, the staggered first spacing 14 facilitates the laying and overlapping of interlayer materials and improves the interlayer connection strength.

[0133] The first wall segment 301 and the second wall segment 302 may have the same inclination angle, or may have different inclination angles.

[0134] Continue to refer Fig.12 In another specific embodiment of the present application, the splicing sheet assembly 100 includes a third guide layer 111 and a sheet group 110 stacked along the thickness direction Z of the pultruded main beam, the third guide layer 111 is arranged between the sheet group 110 and the pultruded assembly 11, and the sheet group 110 includes sheets stacked along the thickness direction Z of the pultruded main beam and a fourth guide layer 102 arranged between the sheet layers.

[0135] The defect grooves 300 of multiple layers of thickness are laid out through multiple layers of sheets to reduce the probability of secondary defects and improve the repair effect. The fourth guide layer 102 is arranged between the sheet layers to improve the resin penetration effect and ensure the overall strength of the sheet group 110 and the connection strength between the sheet group 110 and the pultrusion assembly 11.

[0136] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for repairing a wind turbine blade pultruded main beam, characterized in that: include: Obtaining a main beam middle piece of a wind turbine blade pultruded main beam filling splicing piece assembly; A reinforcement layer having a trend of gradually shrinking toward the middle at both ends along the span of the pultruded main beam is laid along the span of the pultruded main beam to the main beam middle piece and completely covers the splicing piece assembly to obtain a main beam repair piece.

2. The method for repairing a wind turbine blade pultruded main beam according to claim 1, characterized in that: The reinforcing layers having a trend of gradually shrinking toward the middle along the two ends of the pultruded main beam in the span direction are laid along the pultruded main beam to the main beam middle piece and completely cover the splicing sheet assembly, including: Laying the first guide layer in the reinforcement layer to the middle piece of the main beam along the span direction of the pultruded main beam and completely covering the splicing sheet assembly; Laying the reinforcing layers at both ends of the reinforcing layer along the span direction of the pultruded main beam and having a trend of gradually contracting toward the middle along the span direction of the pultruded main beam to the first guide layer and covering the splicing sheet assembly; The second guide layer in the reinforcement layer is laid to the reinforcement layer along the span direction of the pultruded main beam, and is connected to the first guide layer on both sides along the span direction of the pultruded main beam.

3. The method for repairing a wind turbine blade pultruded main beam according to claim 2, characterized in that: The reinforcing layer having a trend of gradually shrinking toward the middle at both ends of the reinforcing layer along the span direction of the pultruded main beam is laid along the span direction of the pultruded main beam to the first guide layer and covers the splicing sheet assembly, including: The multi-layer uniaxial fiber layer is stacked along the thickness direction of the pultruded main beam, and the multi-layer uniaxial fiber layer is arranged along both ends of the pultruded main beam in a gradually contracting trend toward the middle, so as to obtain the reinforcing layer in the reinforcing layer; The reinforcement layer is laid along the span direction of the pultruded main beam to the first guide layer and covers the splicing sheet assembly.

4. The method for repairing a wind turbine blade pultruded main beam according to claim 1, characterized in that: The main beam middle piece of the wind turbine blade pultruded main beam filling splicing piece assembly comprises: At the defect position of the pultruded main beam of the wind turbine blade, a defect groove having an opening increasing trend at both ends along the span direction of the pultruded main beam is obtained; Fill the defective groove with the splicing piece assembly to obtain the main beam middle piece.

5. The method for repairing a wind turbine blade pultruded main beam according to claim 4, characterized in that: The defective position of the pultruded main beam of the wind turbine blade is obtained to obtain a defective groove with an opening increasing trend at both ends along the span direction of the pultruded main beam, including: Cutting off at least one pultruded component at a defective position of the pultruded main beam of the wind turbine blade to remove the defective structure; The cross-section of the pultruded component is processed to obtain defective grooves with an increasing opening trend at both ends along the span direction of the pultruded main beam.

6. The method for repairing a wind turbine blade pultruded main beam according to claim 5, characterized in that: The method of cutting off at least one pultruded component at a defective position of the pultruded main beam of the wind turbine blade to remove the defective structure comprises: At the defective position of the pultruded main beam of the wind turbine blade, at least two pultruded components along the thickness direction of the pultruded main beam are staggered and cut off along the span direction of the pultruded main beam to remove the defective structure.

7. The method for repairing a wind turbine blade pultruded main beam according to claim 5, characterized in that: The method of cutting off at least one pultruded component at a defective position of the pultruded main beam of the wind turbine blade to remove the defective structure comprises: A pultruded plate in at least one pultruded assembly that cuts off a defective position of a pultruded main beam of a wind turbine blade; The guide fiber layer in the pultruded component is cut off to remove the defective structure.

8. The method for repairing a wind turbine blade pultruded main beam according to claim 4, characterized in that: The method of filling the defective groove with the splicing piece assembly to obtain the main beam middle piece comprises: Laying the third guide layer in the splicing sheet assembly to the defective groove; The sheet group in the splicing sheet assembly is laid on the third guide layer to fill the defective groove and obtain the main beam middle piece.

9. The method for repairing a wind turbine blade pultruded main beam according to claim 8, characterized in that: The step of laying the sheet group in the splicing sheet assembly to the third guide layer to fill the defective groove and obtain the main beam middle piece comprises: Laying the first sheet material in the splicing sheet assembly to the third guide layer; Laying the fourth guide layer in the splicing sheet assembly onto the first sheet; The second sheet material in the splicing sheet assembly is laid on the fourth guide layer to fill the defective groove and obtain the main beam middle piece.

10. A pultruded main beam, characterized in that: include: Pultruded components stacked in the thickness direction of the pultruded main beam; A splicing sheet assembly is disposed in the pultrusion assembly; The reinforcing layer completely covers the splicing sheet assembly, and the reinforcing layer includes two ends along the span direction of the pultruded main beam, which have a trend of gradually shrinking toward the middle.

11. The pultruded main beam according to claim 10, characterized in that: The reinforcing layer includes a first guide layer, a reinforcement layer and a second guide layer which are sequentially stacked along the thickness direction of the pultruded main beam, and the second guide layer covers both ends of the reinforcement layer along the span direction of the pultruded main beam and is connected to the first guide layer.

12. The pultruded main beam according to claim 11, characterized in that: The reinforcing layer comprises a plurality of uniaxial fiber layers stacked along the thickness direction of the pultruded main beam, and the plurality of uniaxial fiber layers comprise inclined surfaces which gradually contract toward the middle at both ends along the span direction of the pultruded main beam.

13. The pultruded main beam according to claim 10, characterized in that: The pultrusion component includes a defective groove along the thickness direction of the pultrusion main beam, the splicing piece component is arranged in the defective groove, and the defective groove includes a side wall with an opening increasing trend along the span direction of the pultrusion main beam.

14. The pultruded main beam according to claim 13, characterized in that: The side wall of the defective groove comprises a first wall segment and a second wall segment along the thickness direction of the pultruded main beam, and the first wall segment and the second wall segment are staggered along the span direction of the pultruded main beam.

15. The pultruded main beam according to claim 14, characterized in that: The splicing sheet assembly includes a third guide layer and a sheet group stacked along the thickness direction of the pultruded main beam, the third guide layer is arranged between the sheet group and the pultruded assembly, and the sheet group includes sheets stacked along the thickness direction of the pultruded main beam and a fourth guide layer arranged between the sheet layers.

Images