Segmented wind turbine blade connection structure based on cementation connection and process method

Abstract

The invention discloses a sectional type wind turbine blade connecting structure based on cementation connection and a technological method, and aims to solve the technical problems in the manufacturing, transporting and mounting processes of large-scale wind turbine blades. The blade connecting structure comprises a main blade structure and a connecting pin component, wherein the main blade structure is connected by utilizing a gluing mode between a connecting pin and a pin hole. Due to the fact that the connecting pin is made of the material consistent with the blade structure, and the connecting pin and the blade are bonded in a segmented mode through the glue material consistent with the resin material in the blade composite material, it is guaranteed that the material performance and the mechanical performance of the connecting part and the blade main structure are consistent; and meanwhile, the design of the connecting pins can realize good load transmission between segmented parts. And a plurality of glue filling holes are formed in the connecting pin hole in advance, so that the good performance in the glue filling process and the resin curing process can be ensured. Effective connection of the sectional type wind turbine blades can be effectively achieved, and the requirement for long-term operation of a wind turbine unit is met.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, to the segmented design and connection technology of wind turbine blades, and particularly to a segmented blade connection structure and process method for wind turbines, which can effectively connect different structures of blades segmented along the spanwise direction by adhesive bonding and achieve safe and efficient operation. Background Technology

[0002] With the arrival of large-megawatt units come taller towers and longer blades. As the blade length increases, the difficulties in the production, transportation, and installation of large and super-large wind turbine blades also gradually increase.

[0003] First, the manufacturing requirements for large and super-large blades are much more stringent. Not only must the blades possess sufficient rigidity and strength to withstand strong winds, gravity, and centrifugal forces during rotation, but they also need high fatigue resistance and durability to ensure reliability during long-term operation. During manufacturing, glass fiber reinforced composite materials or carbon fiber composite materials are typically used. The processing and manufacturing processes for these materials are complex, especially in the production of super-large blades, where extremely high precision and process control are required.

[0004] Secondly, the transportation of ultra-large blades has become significantly more difficult. The length and weight of blades are constantly increasing, while the spatial constraints and route conditions during transportation remain largely unchanged. For some remote wind farms, especially in mountainous and hilly areas, existing transportation conditions are insufficient to meet the demands of transporting ultra-large blades. Conventional methods of transporting integral blades not only suffer from high costs and long transit times, but may also fail to reach their destination smoothly due to poor road conditions or insufficient turning radius.

[0005] To address the aforementioned issues, segmented blade design and manufacturing is an effective means to address the trend towards larger blades. Segmented blades involve manufacturing the entire blade structure as a single unit, dividing it into two or more separate components. This reduces the difficulties of blade manufacturing and transportation. After the blades are transported to the wind farm, they are assembled and the turbine begins operation. This requires segmented blades to have a robust segmented connection structure and connection method, enabling rapid and reliable installation at the wind farm. Segmented design not only reduces the manufacturing and transportation difficulties of ultra-large blades but also improves the efficiency of on-site installation at the wind farm.

[0006] Currently, there is some research on segmented blade connection methods and structures both domestically and internationally. However, structures effectively applicable to the segmented connection of large and ultra-large blades are still scarce. Existing connection solutions mainly focus on mechanical connections, such as bolts or rivets, but these methods have limitations in terms of load-bearing capacity, fatigue resistance, and installation efficiency. Furthermore, existing technologies often lack long-term reliable operational verification. In practical applications, due to environmental factors and material aging, fatigue damage may occur in the connection parts, thus affecting the safety and stability of the entire wind turbine unit.

[0007] In summary, as wind turbine generators develop towards larger and ultra-larger sizes, segmented blade design is increasingly becoming a crucial technical means to solve manufacturing, transportation, and installation challenges. However, existing segmented blade connection structures and methods still present numerous problems, particularly regarding the long-term reliability, mechanical performance matching, and environmental adaptability of large blades, requiring further technological innovation. Therefore, designing a segmented blade connection structure that meets the structural requirements of ultra-large blades, ensures long-term reliable operation, and facilitates rapid on-site installation is a pressing technical problem for the wind power industry. Summary of the Invention

[0008] (I) Purpose of the Invention

[0009] In response to the increasing difficulties in blade production, transportation, and installation caused by the continuous increase in the size of large wind turbine blades, and the shortcomings of existing segmented blade connection structures in terms of applicability, reliability, and long-term operational verification, this invention aims to provide a segmented wind turbine blade connection structure and process method based on adhesive bonding to solve at least one of the above-mentioned and other technical problems in the existing technology. By pre-fabricating connecting pin holes and glue injection holes on the mating end faces of the blade segments, the segmented blades are connected on-site using connecting pins, and finally achieving adhesive curing. This allows the segmented blades to achieve reliable connection quickly and effectively in the wind farm environment, ensuring that the connected blades have good mechanical properties and long-term operational stability.

[0010] (II) Technical Solution

[0011] To achieve the objective of this invention and solve its technical problems, the present invention adopts the following technical solution:

[0012] The first objective of this invention is to provide a segmented wind turbine blade connection structure based on adhesive bonding, used to realize the segmented manufacturing, transportation, and on-site assembly of wind turbine blades, ensuring rapid and reliable connection between blade segments, including a main blade structure and connecting pin components, wherein:

[0013] The main blade structure is divided into several blade segments arranged sequentially and connected sequentially by adhesive bonding along its length from the blade root to the blade tip. The span and position of each blade segment are determined according to the overall length of the main blade structure, the blade load distribution and / or transportation constraints.

[0014] Each blade segment has multiple prefabricated half pin holes that are open only on the end face side and extend axially on its docking end face. The prefabricated half pin holes on the docking end faces of two adjacent blade segments correspond one-to-one. After the prefabricated half pin holes on the docking end faces of two adjacent blade segments are docked one-to-one, several connecting pin holes that are distributed circumferentially and closed at both ends are formed.

[0015] Each of the aforementioned connecting pin holes accommodates and provides a connecting pin component. The connecting pin component is an axially extending columnar structure with a length equal to the sum of the depths of two interlocking prefabricated half-pin holes. Its outer diameter is adapted to the inner diameter of the pin hole. When in the installation state, one end of the connecting pin component is inserted into and fixed in one of the prefabricated half-pin holes of the connecting pin hole that is adapted to it, and the other end is inserted into and fixed in the other prefabricated half-pin hole of the connecting pin hole that is adapted to it, forming an interconnected integral structure.

[0016] Each blade segment has a pre-fabricated half-pin hole on its inner wall and the outer surface of the blade. Several axially distributed injection holes are provided between the inner wall and the outer surface of the blade and are connected to the inner cavity of the pin hole. After the connecting pin component is inserted into the inner cavity of the pin hole, the resin is injected into the gap between the inner wall of the pin hole and the connecting pin through each injection hole. After the resin is fully filled and cured, the adhesive connection between the connecting pin hole and the connecting pin component is achieved.

[0017] The second objective of this invention is to provide a segmented wind turbine blade connection process based on adhesive bonding, used to realize the segmented manufacturing, transportation, and on-site assembly of wind turbine blades, and to ensure rapid and reliable connection and long-term operational stability between blade segments through adhesive bonding, including:

[0018] SS1. Blade segment location determination: Based on the overall length of the wind turbine blade, structural strength requirements and / or transportation constraints, determine the blade segment location and load distribution at the segment, and divide the main blade structure into several sequentially arranged blade segments along its length from the blade root to the blade tip.

[0019] SS2. Design and fabrication of segmented connecting pin components: Based on the load distribution at the blade segment, analyze and determine the quantity, size, and arrangement parameters of the segmented connecting pin components to be used, so as to meet the loads borne by the blade during operation, and fabricate the corresponding segmented connecting pin components based on the analysis results.

[0020] SS3. Design and preparation of prefabricated semi-pin holes: Based on the determined number, size and arrangement parameters of the segmented connecting pin components, determine the number, size and spacing distribution of prefabricated semi-pin holes on the segmented mating end face of the blade. The prefabricated semi-pin holes are mainly distributed on the blade main beam part on the suction side and pressure side of the mating end face, and several glue injection holes are set on the side wall of each prefabricated semi-pin hole. The number of glue injection holes is adapted to the inner diameter of the pin hole and the resin flow path.

[0021] SS4. Blade segment on-site connection: At the installation site, insert one end of the prepared connecting pin component into each of the pre-made half pin holes on the connecting end face of one blade segment in sequence. Then, align and connect the pre-made half pin holes on the connecting end face of the adjacent blade segment with each connecting pin component, so that the other end of each connecting pin component is inserted into each of the pre-made half pin holes on the connecting end face of the adjacent blade segment.

[0022] SS5. Resin Injection and Curing: After the mating end faces of each adjacent blade segment are tightly attached and reach the expected connection position, resin is injected into the gap between each connecting pin component and the connecting pin hole through the injection holes pre-set on the side wall of each pin hole. After the resin is filled, it is cured by controlling the temperature and time, and finally a firm bond is achieved between each connecting pin component and the connecting pin hole.

[0023] SS6. Blade Surface Treatment: After the resin has cured, the surface of the blades that have been joined is treated as necessary (such as grinding the glue inlet and applying surface paint) to ensure the flatness and appearance quality of the joint, while increasing its weather resistance and corrosion resistance to ensure the long-term stable operation of the blades.

[0024] (III) Technical Effects

[0025] Compared with the prior art, the design and process method of the segmented wind turbine blade connection structure based on adhesive bonding proposed in this invention have the following significant advantages:

[0026] (1) This invention enables rapid connection of segmented structures in wind farm environments. Compared to traditional mechanical connection methods, adhesive bonding can effectively improve the consistency of mechanical properties between blade segments, reduce stress concentration at the connection points, and avoid fatigue damage and loosening caused by mechanical connectors. This connection method can adapt to the complex loads that wind turbines bear during long-term operation, such as wind load, gravity, and centrifugal force, thereby improving the stability and service life of the entire blade structure.

[0027] (2) This invention can meet the requirements of reliable connection and safe operation of blades under long-term operating conditions. The combination of prefabricated semi-pin holes and connecting pin components ensures precise alignment and load transfer between blade segments. In particular, by providing glue-filling holes on the sidewalls of the pin holes, sufficient resin filling and curing can be achieved, thereby ensuring excellent shear resistance and fatigue resistance of the connection parts during long-term operation. This connection structure can adapt to various extreme conditions in wind farm environments, such as high wind speeds, low temperatures, and corrosive environments, ensuring stable operation of the blades even under harsh conditions. Furthermore, the resin material used in the adhesive connection has good corrosion resistance, weather resistance, and anti-aging properties, ensuring that the connection parts remain firmly fixed even after long-term exposure to the wind farm environment.

[0028] (3) By manufacturing the blades in segments along their length, this invention can significantly reduce the difficulties and limitations encountered in the manufacturing and transportation of ultra-large blades. The segmented blades can be transported to the wind farm using conventional transportation tools, avoiding the space constraints and high costs associated with transporting whole blades, thus improving the manufacturing and installation efficiency of wind turbine blades, and is particularly suitable for on-site assembly of ultra-large wind turbine generator sets. Attached Figure Description

[0029] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings, wherein:

[0030] Figure 1 The diagram shown is a schematic diagram of the segmented wind turbine blade connection structure based on adhesive bonding according to the present invention (without connecting pin components);

[0031] Figure 2 The diagram shows a segmented wind turbine blade connection structure based on adhesive bonding according to the present invention (with connecting pin components).

[0032] Figure 3 The diagram shows a flowchart of the segmented wind turbine blade connection method based on adhesive bonding according to the present invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1- Blade segment near the blade root, 2- Blade segment near the blade tip, 3- Pre-fabricated semi-pin hole of the blade segment near the blade root, 4- Pre-fabricated semi-pin hole of the blade segment near the blade tip, 5- Glue filling hole, 6- Connecting pin component. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. The described embodiments are some, but not all, of the embodiments of this invention. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0036] This invention aims to provide a segmented wind turbine blade connection structure and process based on adhesive bonding. By pre-fabricating connecting pin holes and glue injection holes on the mating end faces of the blade segments, and connecting the segmented blades on site using connecting pins, the adhesive bonding is finally achieved. This allows the segmented blades to achieve reliable connection quickly and effectively in the wind farm environment, ensuring that the connected blades have good mechanical properties and long-term operational stability.

[0037] Example 1

[0038] As a specific example, such as Figure 1 , 2 As shown, the segmented wind turbine blade connection structure based on adhesive bonding according to an embodiment of the present invention includes a main blade structure and connecting pin components. The main blade structure is divided into several blade segments arranged sequentially and connected sequentially by adhesive bonding along its length from the blade root to the blade tip. The span and position of each blade segment are determined based on the overall length of the main blade structure, the blade load distribution, and / or transportation constraints. In this embodiment, the main blade structure is divided into two blade segments: blade segment 1 near the blade root and blade segment 2 near the blade tip. Each blade segment has multiple prefabricated semi-pin holes distributed circumferentially on its mating end face, open only on the end face side and extending axially. Specifically, blade segment 1 near the blade root has prefabricated semi-pin holes 3, and blade segment 2 near the blade tip has prefabricated semi-pin holes 4. The prefabricated semi-pin holes on the mating end faces of adjacent blade segments correspond one-to-one, and after the prefabricated semi-pin holes on the mating end faces of adjacent blade segments are mated, several connecting pin holes distributed circumferentially and closed at both ends are formed.

[0039] Each connecting pin hole accommodates and houses a connecting pin component 6. The connecting pin component 6 is an axially extending columnar structure, the length of which is the sum of the depths of two mating prefabricated half-pin holes, and its outer diameter matches the inner diameter of the pin hole. In the installation state, one end of the connecting pin component 6 is inserted into and fixed in one of the prefabricated half-pin holes that matches it, and the other end is inserted into and fixed in the other prefabricated half-pin hole that matches it, forming an interconnected integral structure.

[0040] To ensure a strong connection, each blade segment 1 and 2 has prefabricated semi-pin holes 3 and 4 on its mating end face, each with several axially distributed injection holes 5 that communicate with the inner cavity of the pin hole between its inner wall and the outer surface of the blade. The injection holes 5 are used to inject resin into the gap between the inner wall of the pin hole and the connecting pin after the connecting pin component 6 is inserted into the inner cavity of the pin hole. After the resin is fully filled and cured, a bonded connection is achieved between the connecting pin hole and the connecting pin component 6.

[0041] In a preferred embodiment, the prefabricated semi-pin holes on each blade segment are distributed symmetrically on the blade main spar of the mating end face, on both the suction and pressure sides. This arrangement ensures that the connection structure can effectively withstand bending and / or torsional loads during blade operation. The number, size, and spacing of the prefabricated semi-pin holes are determined based on the load and stress distribution at different segments of the main blade structure. Specifically, the number and size of the prefabricated semi-pin holes on the mating end face near the blade root are greater than those near the blade tip, to accommodate the spanwise load distribution characteristics of the blade and ensure that each segment connection can withstand the corresponding load.

[0042] In a preferred embodiment, the material of the connecting pin component 6 matches the material of the main blade structure. Preferably, it is a composite material identical to the main blade structure or a metallic material with similar mechanical properties, such as glass fiber reinforced composite material or carbon fiber material. This ensures that the connecting part has consistent material and mechanical properties with the main blade structure, reducing stress concentration caused by differences in material properties and improving the overall structural reliability and durability. The size, quantity, and specific arrangement of the connecting pin component 6 are determined based on the load and stress distribution in different segments of the main blade structure.

[0043] In a preferred embodiment, the axial extension length of each prefabricated half pin hole 3, 4 is half the length of the connecting pin member 6, so that after the adjacent two blade segments 1, 2 are joined, half of the connecting pin member 6 is inserted into the prefabricated half pin hole of one blade segment, and the other half is inserted into the prefabricated half pin hole of another adjacent blade segment, so that the midpoint of the connecting pin member 6 is located between the joint end faces of the two blade segments 1, 2, thereby achieving a uniform load distribution.

[0044] In a preferred embodiment, in the connection structure between the mating end faces of two adjacent blade segments, only one connecting pin member 6 is configured with a transition fit with the connecting pin hole to provide axial and radial positioning during the blade segment connection process. The remaining connecting pin members 6 are configured with a clearance fit with the connecting pin holes to ensure sufficient resin injection between the connecting pin members 6 and the connecting pin holes, ensuring uniform glue distribution and complete filling of the gaps, and forming a strong adhesive bond after curing.

[0045] In a preferred embodiment, the two ends of the connecting pin component 6 are provided with stress reduction structures. These structures are gradually increasing rounded transitions or tapered structures, which are used to reduce stress concentration at the connection between the connecting pin component 6 and the prefabricated half-pin hole, enhance the compressive strength and durability of the connecting structure, and guide the connecting pin component 6 to be smoothly inserted into the prefabricated half-pin hole during the installation process through the stress reduction structure.

[0046] In a preferred embodiment, the outer surface of the connecting pin member 6 and / or the inner wall of the pre-formed semi-pin hole are provided with a surface treatment structure to enhance the bonding strength. This surface treatment structure can be a spiral groove or annular groove distributed axially or circumferentially, or a roughened surface formed by machining, chemical etching, or other methods. This design increases the contact area between the outer surface of the connecting pin member 6 and / or the inner wall of the pre-formed semi-pin hole and the resin, improving the bonding strength, and also facilitating resin flow and distribution.

[0047] In a preferred embodiment, 3-8 injection holes 5 are provided on the inner wall of each pre-fabricated semi-pin hole, and the injection holes 5 are evenly distributed along the axial direction of the pre-fabricated semi-pin hole, with at least one injection hole 5 located in the middle of the pre-fabricated semi-pin hole. This arrangement ensures that the resin can evenly and fully fill the gap between the connecting pin member 6 and the pre-fabricated semi-pin hole. The diameter of each injection hole 5 is set to 2-5 mm to ensure the fluidity of the resin and the injection efficiency, and to facilitate sealing after injection.

[0048] The segmented wind turbine blade connection structure based on adhesive bonding described in this invention, through the ingenious design of prefabricated semi-pin holes, connecting pin components, and glue injection holes, enables the segmented manufacturing, transportation, and on-site assembly of wind turbine blades. This structure not only ensures rapid and reliable connection between blade segments but also improves the overall structural strength and durability. Reasonable material selection, stress reduction design, and surface treatment further enhance the performance of the connection structure. The flexible glue injection system design ensures bonding quality, thereby improving the reliability and service life of the entire blade structure.

[0049] Example 2

[0050] Based on Embodiment 1 above, Embodiment 2 takes a MW-class wind turbine blade as an example to further describe in detail the segmented wind turbine blade connection process method based on adhesive bonding of the present invention. This method not only realizes the segmented manufacturing, transportation and on-site assembly of wind turbine blades, but also ensures rapid and reliable connection between blade segments and long-term operational stability through adhesive bonding. Figure 3 As shown, the main implementation steps of this method are as follows:

[0051] SS1. Determining the position of blade segments

[0052] Based on the overall length of the wind turbine blade, structural strength requirements, and / or transportation constraints, this embodiment determines that the blade will be segmented at one-third of its length from the tip. Specifically, considering that the total length of the MW-class wind turbine blade is 75 meters and the maximum load length of the transport vehicle is 50 meters, the blade is divided into two sections: a 50-meter root section and a 25-meter tip section. When selecting the segmentation location, the mechanical properties of the blade must be fully considered, especially the bending moment, shear force, and torque loads it will experience during operation. By selecting a reasonable segmentation location, the transportation and on-site installation process after segmentation can be optimized while meeting the blade's strength and stiffness requirements.

[0053] SS2. Design and fabrication of segmented connecting pins

[0054] After the blade is segmented, the load at the segment is calculated using finite element analysis or other mechanical analysis methods. Based on the load distribution at the segment, the number, size, and arrangement parameters of the segmented connecting pin components are determined to meet the static and dynamic loads borne by the blade during operation. In this embodiment, considering load distribution and structural stability, three connecting pin components are respectively set on the pressure surface and suction surface of the blade main beam, and are evenly distributed at the main beam. The material of each connecting pin component is preferably made of glass fiber reinforced composite material, which has high specific strength and specific stiffness and can effectively withstand the cyclic loads and fatigue stresses generated during wind turbine operation. Furthermore, in the design, the two ends of the connecting pin are preferably provided with rounded transition sections or conical structures to reduce stress concentration, improve the reliability of the connecting pin in long-term operation, and facilitate installation.

[0055] Preferably, the outer surface of the connecting pin component undergoes special treatment, employing a combination of mechanical grinding and chemical etching to create a micron-level rough surface, thereby enhancing its adhesion strength to the resin. Simultaneously, spiral shallow grooves with a depth of 0.5 mm and a pitch of 10 mm are designed on the connecting pin surface. This design increases the surface area and facilitates resin flow and distribution.

[0056] SS3. Design and fabrication of prefabricated semi-pin holes

[0057] Based on the number, size, and arrangement parameters of the segmented connecting pin components determined in step SS2, the number, size, and spacing of the pre-reserved connecting pin holes at the blade segment locations are determined, and a grouting hole is provided in each pin hole. In this embodiment, three prefabricated semi-pin holes are respectively set on the pressure surface and suction surface at the blade main beam location, and are evenly distributed at the main beam location to ensure that the connection structure can withstand the complex loads during blade operation. To ensure that the resin can evenly fill each pin hole during the bonding process and form a strong bond, several grouting holes are reserved on the sidewall of each prefabricated semi-pin hole. In this embodiment, five grouting holes are provided in each prefabricated semi-pin hole, and the distribution of the grouting holes is evenly arranged along the axial direction of the pin hole to ensure that the resin can fully flow and fill the gap between the entire pin hole and the connecting pin component.

[0058] Preferably, the diameter of the potting hole is typically set to 2 to 5 mm, depending on the resin flowability and the size of the connecting pin. The location of the potting hole also needs to be optimized through mechanical analysis to ensure that the resin can be evenly distributed around the connecting pin during the curing process, avoiding poor adhesion or uneven curing.

[0059] SS4. Field connection of segmented blades

[0060] At the segmented blade installation site, the blade segments are joined together. First, one end of a prefabricated connecting pin component is inserted sequentially into a prefabricated half-pin hole on the mating end face of the blade segment closest to the blade root. During insertion, a specially designed guide tool is used to ensure the connecting pin is precisely aligned with the prefabricated half-pin hole. Then, a large lifting device is used to slowly move the blade segment closest to the blade tip into place, so that the prefabricated half-pin hole on its mating end face fits onto the inserted connecting pin component, achieving the connection between adjacent blade segments. During installation, to ensure the accuracy of the segmented blade joining, it is preferable to select at least one connecting pin with a transition fit between the pin and the half-pin hole to provide precise axial and radial positioning, while the remaining connecting pins have a clearance fit between them to allow for resin injection and flow.

[0061] SS5. Resin Injection and Curing

[0062] After adjacent sections of the blade are aligned and reach the intended connection position, resin is injected into the space between the connecting pin and the pin hole through the injection hole. After full curing, the segmented blades are connected. To ensure the resin fully fills the gap between the pin hole and the connecting pin component, this embodiment preferably uses vacuum-assisted injection technology. Before injection, the gap between the pin hole and the connecting pin is evacuated to remove air and potential impurities, and then the resin is injected under negative pressure. After resin injection, the curing stage begins. The resin curing process uses multi-stage temperature control. Initial curing is performed at room temperature to reduce shrinkage stress, and then the temperature is gradually increased to 60°C to 80°C for final curing. This curing process improves the mechanical strength and heat resistance of the resin, ensuring that the blades maintain good connection performance even under extreme temperatures. The resin used is a low-temperature curing epoxy resin, which has excellent moisture resistance and aging resistance, making it suitable for low-temperature and high-humidity conditions in wind farm environments. In addition, low-temperature curing epoxy resin generates less heat during the curing process, which can effectively avoid stress concentration problems caused by thermal expansion, thereby further improving the long-term operational reliability of the blades.

[0063] SS6. Blade Surface Treatment

[0064] After the resin has cured, the surface of the connected blades is treated, such as grinding the glue inlet and applying surface paint, to ensure the flatness, appearance quality and long-term stability of the connection.

[0065] Through the above steps, the design and process of the segmented wind turbine blade connection structure based on adhesive bonding of this invention have been realized. This method not only solves the technical challenges in the manufacturing, transportation, and installation of large wind turbine blades, but also ensures reliable connection and long-term stability between blade segments through innovative adhesive bonding technology, making it particularly suitable for the production and installation needs of large wind turbine blades. Practical application shows that wind turbine blades connected using this method have not exhibited any abnormalities at the connection points after long-term actual operation testing, fully demonstrating the effectiveness and reliability of this connection method.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A segmented wind turbine blade connection structure based on adhesive bonding, comprising a main blade structure and a connecting pin component, characterized in that: The main blade structure is divided into several blade segments arranged sequentially and connected sequentially by adhesive bonding along its length from the blade root to the blade tip. The span and position of each blade segment are determined according to the overall length of the main blade structure, the blade load distribution and / or transportation constraints. Each blade segment has multiple prefabricated half pin holes that are open only on the end face side and extend axially. The prefabricated half pin holes on the mating end faces of two adjacent blade segments correspond one-to-one. After the prefabricated half pin holes on the mating end faces of two adjacent blade segments are mated one-to-one, several connecting pin holes that are distributed circumferentially and closed at both ends are formed. Each of the aforementioned connecting pin holes accommodates and provides a connecting pin component. The connecting pin component is an axially extending columnar structure with a length equal to the sum of the depths of two interlocking prefabricated half-pin holes. Its outer diameter is adapted to the inner diameter of the pin hole. When in the installation state, one end of the connecting pin component is inserted into and fixed in one of the prefabricated half-pin holes of the connecting pin hole that is adapted to it, and the other end is inserted into and fixed in the other prefabricated half-pin hole of the connecting pin hole that is adapted to it, forming an interconnected integral structure. Each blade segment has a pre-fabricated half-pin hole on its inner wall and the outer surface of the blade. Several axially distributed injection holes are provided between the inner wall and the outer surface of the blade and communicate with the inner cavity of the pin hole. After the connecting pin component is inserted into the inner cavity of the pin hole, the resin is injected into the gap between the inner wall of the pin hole and the connecting pin through each injection hole. After the resin is fully filled and cured, the adhesive connection between the connecting pin hole and the connecting pin component is achieved.

2. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, Each prefabricated semi-pin hole on each blade segment is distributed on the blade main beam on the suction and pressure sides of the mating end face, and is symmetrically distributed on the main beam to ensure that the connection structure can effectively withstand the bending load and / or torsional load during the blade operation. The number, size and spacing of the prefabricated semi-pin holes are determined according to the load and stress distribution of the main blade structure in different segments. The number and size of the prefabricated semi-pin holes on the mating end face near the blade root are greater than those on the mating end face near the blade tip.

3. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, The material of the connecting pin component is matched with the material of the main blade structure to ensure that the connecting part and the main blade structure have consistent material and mechanical properties, and its size, quantity and specific arrangement position are determined according to the load and stress distribution of the main blade structure in different segments.

4. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, The axial extension length of each of the prefabricated half pin holes is half the length of the connecting pin member, so that after the adjacent two blade segments are docked, half of the connecting pin member is inserted into the prefabricated half pin hole of one blade segment, and the other half is inserted into the prefabricated half pin hole of another adjacent blade segment. The midpoint of the connecting pin member is located between the docking end faces of the two blade segments.

5. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, In the connection structure between the joint end faces of two adjacent blade segments, only one connecting pin component and the connecting pin hole are configured with a transition fit to provide axial and radial positioning during the blade segment connection process. The remaining connecting pin components and the connecting pin holes are configured with a clearance fit to ensure sufficient resin injection between the connecting pin components and the connecting pin holes.

6. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, The connecting pin component has stress-reducing structures at both ends. These structures are either gradually increasing rounded corners or tapered shapes, which are used to reduce stress concentration at the connection between the connecting pin component and the prefabricated half-pin hole, enhance the compressive strength and durability of the connecting structure, and guide the connecting pin component to be smoothly inserted into the prefabricated half-pin hole during installation.

7. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, The outer surface of the connecting pin component and / or the inner wall of the pre-made semi-pin hole are provided with a surface treatment structure to enhance the bonding strength. The surface treatment structure is a spiral groove or annular groove distributed along the axial or circumferential direction, or a roughened surface formed by mechanical processing or chemical etching, in order to increase the contact area between the outer surface of the connecting pin component and / or the inner wall of the pre-made semi-pin hole and the resin.

8. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, Each pre-cast half-pin hole has 3-8 glue-filling holes on its inner wall, and each glue-filling hole is evenly distributed along the axial direction of the pre-cast half-pin hole. At least one of the glue-filling holes is located in the middle of the pre-cast half-pin hole to ensure that the resin can evenly and fully fill the gap between the connecting pin component and the pre-cast half-pin hole. At the same time, the diameter of each glue-filling hole is set to 2-5mm to ensure the fluidity of the resin and the injection efficiency, and to facilitate sealing after the glue is injected.

9. A method for connecting segmented wind turbine blades based on adhesive bonding, characterized in that, The method is implemented through the following steps: SS1. Blade segment location determination: Based on the overall length of the wind turbine blade, structural strength requirements and / or transportation constraints, determine the blade segment location and load distribution at the segment, and divide the main blade structure into several sequentially arranged blade segments along its length from the blade root to the blade tip. SS2. Design and fabrication of segmented connecting pin components: Based on the load distribution at the blade segment, analyze and determine the quantity, size, and arrangement parameters of the segmented connecting pin components to be used, so as to meet the loads borne by the blade during operation, and fabricate the corresponding segmented connecting pin components based on the analysis results. SS3. Design and preparation of prefabricated semi-pin holes: Based on the determined number, size and arrangement parameters of the segmented connecting pin components, determine the number, size and spacing distribution of prefabricated semi-pin holes on the segmented mating end face of the blade. The prefabricated semi-pin holes are mainly distributed on the blade main beam part on the suction side and pressure side of the mating end face, and several glue injection holes are set on the side wall of each prefabricated semi-pin hole. The number of glue injection holes is adapted to the inner diameter of the pin hole and the resin flow path. SS4. Blade segment on-site connection: At the installation site, insert one end of the prepared connecting pin component into each of the pre-made half pin holes on the connecting end face of one blade segment in sequence. Then, align and connect the pre-made half pin holes on the connecting end face of the adjacent blade segment with each connecting pin component, so that the other end of each connecting pin component is inserted into each of the pre-made half pin holes on the connecting end face of the adjacent blade segment. SS5. Resin Injection and Curing: After the mating end faces of each adjacent blade segment are tightly attached and reach the expected connection position, resin is injected into the gap between each connecting pin component and the connecting pin hole through the injection holes pre-set on the side wall of each pin hole. After the resin is filled, it is cured by controlling the temperature and time, and finally a firm bond is achieved between each connecting pin component and the connecting pin hole. SS6. Blade Surface Treatment: After the resin has cured, the blades that have been joined are surface treated to ensure the flatness and appearance quality of the joint, and to increase their weather resistance and corrosion resistance.

10. The segmented wind turbine blade connection structure based on adhesive bonding according to claim 1, characterized in that, In step SS4 above, in the connection structure between the segmented mating end faces of two adjacent blades, only one connecting pin component has a transition fit with the pin hole to achieve positioning during the segmented connection process. The remaining connecting pin components have clearance fits with the pin holes to ensure sufficient resin injection between the connecting pin components and the pin holes. In step SS5 above, the resin injection process adopts vacuum-assisted injection technology. Before injection, the gap between the connecting pin component and the connecting pin hole is evacuated to remove air and potential impurities. Then, the resin is injected under negative pressure to ensure that the resin can uniformly and fully fill the gap between the pin hole and the connecting pin component. At the same time, the resin curing process is completed through multi-stage temperature control. First, preliminary curing is carried out at room temperature to reduce shrinkage stress. Then, the temperature is gradually increased to 60°C to 80°C for final curing, thereby improving the mechanical strength and heat resistance of the resin and ensuring that the blade can maintain good connection performance even under extreme temperatures.

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