Lightning protection assembly for maintenance of wind power blade

Abstract

The utility model relates to the technical field of wind power blade lightning protection, in particular to a lightning protection assembly for wind power blade maintenance, which comprises a repairing sheet, the repairing sheet is arranged on the outer side of a blade shell, one end of the repairing sheet is connected with a blade tip lightning arrester, and one end, far away from the blade tip lightning arrester, of the repairing sheet is connected with a problem lightning arrester. The repairing piece is arranged on the outer surface of the blade shell, a lightning protection system does not need to be repaired by entering the blade shell, the problem that the lightning protection system fails due to the fact that a lightning conductor in the blade is narrow in fracture space and personnel cannot enter the blade for maintenance is solved, operation difficulty and risks are reduced, operation is relatively simple, and maintenance efficiency is high.

Description

Technical Field

[0001] The utility model relates to the technical field of lightning protection for wind turbine blades, in particular to a lightning protection component for repairing wind turbine blades. Background Art

[0002] As an important component of wind power generation, wind turbine blades are mostly installed in open and high-rise areas. Their high position increases the probability of being struck by lightning. Wind turbine blades are all designed with lightning protection. The lightning protection design commonly used at present is in the form of internal lightning conductor + tip and blade body lightning rod. The internal lightning conductor usually uses aluminum wire and copper wire. With the development of large-scale wind turbines, the length of wind turbine blades is also constantly increasing, and the deformation of the blades is also getting larger and larger. The internal lightning conductor of the blade may break. If the break occurs at the tip of the blade, due to the small space, personnel cannot enter to work, and the lightning conductor cannot be repaired. If the lightning conductor is broken and cannot be repaired, it will no longer be able to conduct lightning, causing the entire lightning protection system to fail, which is a high risk. Therefore, it is necessary to find a device and method that can solve the problem of wind turbine blade lightning conductor being unable to be repaired.

[0003] Publication No.: CN114576108A A method for repairing the offset of the copper mesh for lightning protection of wind turbine blades is disclosed. The method achieves lightning protection and electrical conductivity in the area by adding a corrective copper mesh at the position where the structurally designed copper mesh is offset without destroying the structurally designed copper mesh. The method specifically includes the following eight steps: positioning the offset area of ​​the copper mesh and treating the outer surface; prefabrication and laying of the copper mesh connection assembly and the reinforcing copper mesh; laying of the corrective copper mesh; laying of surface felt or other fiberglass fabric on the outer surface of the copper mesh; arrangement of surface auxiliary materials, the infusion system, and the exhaust system; vacuum injection; surface treatment of the repair area and connection of the copper mesh connection assembly to the main lightning conductor of the blade. However, this application is intended to solve the problem of copper mesh offset during the production process of wind turbine blades containing carbon fiber beams. The existing lightning protection system structure cannot be used. The installation and fixation of the connection assembly is relatively complicated, and the narrow space at the blade tip makes it inconvenient for personnel to connect the copper mesh to the lightning conductor.

[0004] Therefore, it is necessary to find a lightning protection device that can be used to repair the broken lightning conductor at the tip of a large wind turbine blade, so as to solve the problem of lightning protection system failure caused by the narrow space at the blade tip and the inability of personnel to enter to repair the lightning conductor in the existing technology. Summary of the Invention

[0005] In view of this, the utility model aims to propose a lightning protection assembly for wind turbine blade maintenance to solve the problem of lightning protection system failure caused by the narrow space at the blade tip where personnel cannot enter to repair the lightning protection line.

[0006] Previously, most domestic wind turbine blades were under 90 meters in length, with the majority measuring 50-60 meters. The blade tip exhibited minimal deformation during operation, preventing lightning conductor breakage. However, with the development of my country's wind power industry, blade sizes have gradually increased, and fiberglass wind turbine blades exceeding 90 meters have now been produced and installed. Blades exceeding 90 meters in length are susceptible to lightning conductor breakage due to significant deformation at the blade tip during operation. However, most installed fiberglass wind turbine blades now utilize an internal lightning conductor combined with a blade body lightning arrester for lightning protection.

[0007] The reason why FRP composite wind turbine blades cannot use external lightning conductors is that when the lightning conductor is in the form of an external lightning conductor, the diameter of the lightning conductor is relatively thick, generally more than 50 square millimeters. When attached to the outside of the blade, it is easy to cause the blade to follow the shape poorly. At the same time, the linear speed of the blade tip can reach hundreds of meters per second during operation, and the shape-following problem will cause more serious consequences. If a metal mesh is used, the exposed metal is easy to cause lightning strikes, damage the lightning conductor, and require repeated repairs.

[0008] At the same time, when the lightning conductor breaks, it needs to be repaired. However, the diameter space at the tip of the blade is about 200-300mm, and people cannot enter.

[0009] In order to solve the problem of repairing the broken lightning conductors of existing fiberglass wind turbine blades, the present application restores conduction by setting a patch on the outer surface of the blade in the broken area. The main method includes confirming the location of the broken area of ​​the lightning conductor, pasting the patch on the outer side of the blade shell in the corresponding area, and detecting whether the conduction is restored. This method solves the problem of lightning protection system failure caused by the narrow space inside the blade where the lightning conductor is broken and personnel cannot enter for maintenance. It can more permanently ensure the lightning strike safety of the blade, has strong operability and high maintenance efficiency.

[0010] In this application, the patch is less than 1mm thick, which has minimal impact on the blade's shape for blades over 100 meters in length. To ensure the patch's conductivity, the inventors limited its cross-sectional area to no less than the conductive cross-sectional area of ​​the blade's lightning conductor. The width is generally between 100-300mm, ensuring the patch's conductivity. Furthermore, for large blades, the blade air receptor typically protrudes 30-50mm beyond the blade shell surface, with a diameter of 6-12mm.

[0011] The technical solution of the present utility model is implemented as follows: a lightning protection assembly for repairing wind turbine blades includes a patch, which is arranged on the outside of the blade shell, one end of the patch is connected to the blade tip lightning rod, and the end of the patch away from the blade tip lightning rod is connected to the problem lightning rod.

[0012] Furthermore, both ends of the patch are folded into a first connecting portion and a second connecting portion, respectively. The first connecting portion is used to connect to the blade tip lightning receptor, and the second connecting portion is used to connect to the problematic lightning receptor.

[0013] Furthermore, the connection surface area between the first connection portion and the blade tip lightning receptor and the connection surface area between the second connection portion and the problematic lightning receptor are not less than the longitudinal cross-sectional area of ​​the patch.

[0014] Furthermore, the patch and the blade tip lightning receptor are connected as well as the patch and the problematic lightning receptor by means of rivet connection or screw fastening.

[0015] Furthermore, the prefabricated part made of the patch is bonded to the blade shell by an adhesive, or the patch is directly bonded to the blade shell by the adhesive.

[0016] Furthermore, the preform of the patch is made by a vacuum infusion molding process.

[0017] Furthermore, the patch is bonded to the blade shell, and sealant is applied to the outer surface and edge of the patch to protect the transition.

[0018] Furthermore, the patch is a metal mesh or a metal foil, the thickness of the patch does not exceed 1 mm, and the width ranges from 100 to 300 mm.

[0019] Furthermore, the patch and the blade tip lightning receptor, and the patch and the problematic lightning receptor are connected via connectors.

[0020] Furthermore, the connecting member includes a connecting seat, a boss and a through hole, the connecting seat is a cylinder, the boss is arranged with one end of the connecting seat, the center lines of the connecting seat and the boss are coaxial, the connecting seat is used to connect the problematic lightning rod or the blade tip lightning rod, the boss is used to crimp the repair plate, and the through hole is arranged in the axial direction of the connecting seat and the boss.

[0021] Compared with the existing technology, the lightning protection assembly for wind turbine blade maintenance of the utility model has the following advantages:

[0022] 1. The utility model can restore the conductivity of the blade lightning protection system without entering the interior of the blade to repair the lightning protection wire, solving the problem of lightning protection system failure caused by the narrow space inside the blade where the lightning protection wire is broken and personnel cannot enter for maintenance, and can more permanently ensure the lightning strike safety of the blade; this maintenance method is relatively easy to operate, has strong operability, and high maintenance efficiency.

[0023] 2. The utility model has a simple structure and is easy to process and install by setting the first connecting part and the second connecting part. It can effectively increase the contact area between the patch and the blade tip lightning rod and between the patch and the problem lightning rod, thereby ensuring the conductivity of the connection between the patch and the original lightning protection system.

[0024] 3. The utility model effectively increases the contact area between the patch and the blade tip lightning receptor, and between the patch and the problem lightning receptor by providing a connector, shortens the maintenance time, ensures the conductivity of the connection between the patch and the original lightning protection system, and improves the maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 A schematic diagram of repairing a lightning conductor break in a lightning protection system for wind turbine blades;

[0027] Figure 2 It is a form of bonding between the patch and the blade shell;

[0028] Figure 3 It is another form of bonding the patch to the blade shell;

[0029] Figure 4 Schematic diagram of the patch structure;

[0030] Figure 5 Schematic diagram of the connector structure.

[0031] Description of reference numerals:

[0032] 1. Blade shell; 2. Lightning conductor; 3. Blade body lightning rod; 4. Blade tip lightning rod; 5. Problem lightning rod; 6. Repair piece; 7. Fiberglass cloth; 8. Pad; 9. Adhesive; 10. Sealant; 11. First connecting part; 12. Second connecting part; 13. Connector; 1301. Connecting seat; 1302. Boss; 1303. Through hole. DETAILED DESCRIPTION

[0033] In order to make the technical means, objectives and effects of the present invention easier to understand, embodiments of the present invention are described in detail below with reference to specific drawings.

[0034] It should be noted that all directional and positional terms in this utility model, such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "inner," "outer," "top," "lower," "lateral," "longitudinal," "center," etc., are used only to explain the relative positional relationships and connections between components in a specific state. They are intended solely to facilitate the description of this utility model and do not require that this utility model must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., used in this utility model are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated.

[0035] In the description of this utility model, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections; they can refer to direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0036] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative use of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0037] The utility model discloses a lightning protection assembly for repairing wind turbine blades, comprising: a patch 6, the patch 6 being arranged on the outside of a blade shell 1, one end of the patch 6 being connected to a blade tip lightning receptor 4, and the end of the patch 6 away from the blade tip lightning receptor 4 being connected to a problem lightning receptor 5.

[0038] The repair piece 6 is arranged on the outside of the blade shell 1 and directly covers the area that needs repair. It can quickly and effectively repair the damaged lightning protection components, restore the integrity of the lightning protection system, reduce the downtime of the wind turbine blade, and ensure the conductivity of the lightning protection system.

[0039] This arrangement provides a repair piece 6 on the outer surface of the blade shell 1, eliminating the need to enter the interior of the blade shell 1 for repair, thereby reducing operational difficulty and risk. The operation is relatively simple, the maintenance efficiency is high, and the conductivity of the lightning conductor 2 can be effectively guaranteed. This more durably protects the lightning safety of the blade shell 1 and ensures that the lightning conductor 2 resumes normal function.

[0040] Specifically, the method for using the lightning protection assembly for wind turbine blade maintenance includes the following specific steps:

[0041] S1: Determine the fracture location of the lightning conductor 2 and the faulty lightning receptor 5 by measuring the resistance between the blade tip lightning receptor 4 and the blade body lightning receptor 3;

[0042] S2: After the fracture location area is determined, the outer surface coating of the blade shell 1 in this area is polished;

[0043] S3: After polishing and cleaning, install the patch 6. One end of the patch 6 in the longitudinal direction is connected to the blade tip lightning receptor 4, and the end of the patch 6 away from the blade tip lightning receptor 4 is connected to the problem lightning receptor 5.

[0044] S4: After the repair is completed, the surface coating of the blade shell 1 is restored;

[0045] S5: Measure the resistance from the blade tip lightning rod 4 to the blade root lightning conductor 2, and check the resistance value to determine whether the conduction is restored.

[0046] Use a multimeter to measure the resistance between the blade tip lightning rod 4 and the blade body lightning rod 3, determine the approximate area where the lightning rod 2 is broken and the problem lightning rod 5, determine the area to be repaired based on the measurement results, and mark it, polish the outer surface of the blade shell 1 in the marked area, remove the surface coating, and ensure that the surface is clean and flat, and bond the prefabricated patch 6 to the designated position of the blade shell 1 with adhesive 9, ensuring that one end of the patch 6 is connected to the blade tip lightning rod 4 and the other end is connected to the problem lightning rod 5. Rivets or screws can be used to fix the patch 6 to the blade tip lightning rod 4 and the blade body lightning rod 3, apply sealant 10 on the outer surface and edge of the patch 6 for protection, and ensure that the surface is flat and waterproof. Finally, measure the resistance from the blade tip lightning rod 4 to the blade root lightning rod 2 to confirm whether the conduction is restored.

[0047] This lightning conductor repair method sets a patch 6 on the outer surface of the blade shell 1, and there is no need to enter the interior of the blade shell 1 for repair, which reduces the difficulty and risk of operation. The operation is relatively simple, does not require complex equipment, and has high maintenance efficiency. Only simple tools and materials are needed to complete the repair. The cost is low and the processing is convenient. It can effectively ensure the conductivity of the lightning conductor 2, more durably protect the lightning safety of the blade shell 1, and ensure that the lightning conductor 2 resumes normal function.

[0048] Specifically, in step S1, by measuring the resistance between the blade tip lightning rod 4 and multiple blade body lightning rods 3 respectively, when the resistance value measured from a blade body lightning rod 3 to the blade tip lightning rod 4 is infinite, the area is the broken position area of ​​the lightning conductor 2, and the blade body lightning rod 3 is the problematic lightning rod 5.

[0049] Use a resistance measuring instrument to measure the resistance value between the blade tip lightning rod 4 and each blade body lightning rod 3. When the measured value is infinite or much higher than the normal value, it means that the section of lightning rod 2 has been broken or there is a poor contact problem. It can be preliminarily determined that the lightning rod 2 at the location of the blade body lightning rod 3 is broken. Combined with the actual blade structure and the layout of the lightning rod 2, the specific area of ​​the fracture can be further narrowed down. The blade body lightning rod 3 is the problematic lightning rod 5.

[0050] This setting can quickly determine the approximate position of the lightning conductor 2 through simple resistance measurement, thereby providing a clear direction for subsequent inspection and repair work. The specific size of the resistance value can help accurately judge the specific situation of the lightning conductor 2 without causing any damage to the blade shell 1 structure. The operation is relatively simple and fast, and the measurement cost is low.

[0051] Preferably, the resistance value is measured using a digital multimeter.

[0052] This setting uses a digital multimeter to measure the resistance value. The operation is simple and quick, requiring low operating skills. It can quickly obtain data, and the resistance value is accurate and reliable, which helps to determine the health of the lightning conductor 2.

[0053] Specifically, in step S3, the patch 6 may be a metal mesh or a metal foil, the thickness of the patch 6 does not exceed 1 mm, and the width ranges from 100 to 300 mm.

[0054] Setting the patch 6 as a metal mesh or metal foil can ensure that the patch 6 has good conductivity and mechanical strength; the thickness of the patch 6 does not exceed 1 mm, which can ensure that the patch 6 has sufficient conductivity and better fits the surface of the blade shell 1 after bonding, without forming obvious protrusions or depressions, maintaining the original curved shape of the blade shell 1, and not significantly changing the aerodynamic characteristics of the blade shell 1; the width range of the patch 6 is 100-300 mm, so that the patch 6 has a sufficient cross-sectional area, which helps to ensure the conductivity of the patch 6.

[0055] This arrangement can ensure that the patch 6 has excellent electrical conductivity and high mechanical strength, maintains long-term stability in harsh environments, ensures the safe operation of the wind turbine blade lightning protection system, and further improves the reliability and service life of the wind turbine blade.

[0056] Preferably, the thickness of the patch 6 is 0.3 mm.

[0057] The thickness of 0.3 mm enables the patch 6 to better fit the blade surface without forming obvious protrusions or depressions, maintaining the original curved shape of the blade, and not significantly changing the aerodynamic characteristics of the blade shell 1, thereby reducing wind resistance and maintaining the efficiency of the blade.

[0058] This setting can keep the surface of the blade shell 1 smooth, reduce wind resistance, improve the aerodynamic performance of the blade shell 1, reduce wind noise, and make the installation of the repair piece 6 easier, especially for blade surfaces with larger curvatures, ensuring that the repair piece 6 fits tightly to the blade surface and maintains beauty.

[0059] Specifically, in step S3, the connection between the patch 6 and the blade tip lightning receptor 4, and between the patch 6 and the problematic lightning receptor 5 can be achieved by rivet connection or screw fastening.

[0060] Whether using rivets or screws, both ensure a reliable conductive connection between patch 6 and blade tip lightning receptor 4, and between patch 6 and the problematic lightning receptor 5, ensuring smooth conduction of lightning current. Rivets offer excellent sealing and reliability, while screws provide removability and adjustability. By choosing the right connection method, the safe operation of the wind turbine blade lightning protection system can be ensured. Regular inspection and maintenance can further improve system reliability, minimize impacts on blade performance, and increase the reliability and service life of wind turbine blades.

[0061] This arrangement ensures a high connection strength between the patch 6 and the blade tip lightning receptor 4, and between the patch 6 and the problematic lightning receptor 5, enabling them to withstand high external loads, facilitating rapid installation on site, and providing high reliability.

[0062] Specifically, both ends of the patch 6 are folded into a first connecting portion 11 and a second connecting portion 12 , respectively. The first connecting portion 11 is used to connect to the blade tip lightning receptor 4 , and the second connecting portion 12 is used to connect to the problematic lightning receptor 5 .

[0063] The two ends of the patch 6 are folded into a first connecting portion 11 and a second connecting portion 12, respectively, to avoid excessive resistance caused by insufficient connection area between the patch 6 and the blade tip lightning receptor 4, and between the patch 6 and the problematic lightning receptor 5, which affects the reliable conductive connection between the patch 6 and the blade tip lightning receptor 4, and between the patch 6 and the problematic lightning receptor 5, thereby ensuring that the lightning current can be smoothly conducted.

[0064] This setting helps to ensure the conductivity between the patch 6 and the blade tip lightning rod 4, and between the patch 6 and the problem lightning rod 5, ensuring that the current can be effectively conducted. It has high connection strength, high reliability, and is convenient for on-site installation. Through reasonable design and connection methods, it can minimize the impact on blade performance and improve the reliability and service life of the wind turbine blade lightning protection system.

[0065] Preferably, the first connecting portion 11 and the second connecting portion 12 are triangular or semicircular.

[0066] Preferably, the first connecting portion 11 and the second connecting portion 12 may be preset holes or other forms of connecting components.

[0067] Specifically, the connection surface area between the first connection portion 11 and the blade tip lightning receptor 4 and the connection surface area between the second connection portion 12 and the problematic lightning receptor 5 are both no less than the longitudinal cross-sectional area of ​​the patch 6 .

[0068] The larger connection surface area can ensure good conductivity between the first connection part 11 and the blade tip lightning rod 4, and between the second connection part 12 and the problem lightning rod 5, so that the lightning current can be effectively conducted. At the same time, it ensures the stability of the connection, disperses stress, and reduces material fatigue and damage caused by stress concentration.

[0069] This setting can avoid the influence of large resistance caused by insufficient connection area on the conductive performance of the connection structure, and helps to ensure the reliable connection between the patch 6 and the lightning rod and the smooth conduction of the lightning current, while reducing failures caused by loose connections.

[0070] Specifically, the patch 6 and the blade tip lightning receptor 4 , as well as the patch 6 and the problematic lightning receptor 5 are connected via the connector 13 .

[0071] The connector 13 ensures a reliable electrical connection between the patch 6 and the blade tip lightning rod 4, and between the patch 6 and the problematic lightning rod 5, ensuring that the lightning current can be smoothly transmitted from the blade tip lightning rod 4 to the problematic lightning rod 5, and then transmitted to the ground through the lightning conductor 2, thereby preventing damage to the blades caused by lightning strikes.

[0072] This arrangement can quickly and conveniently connect the patch 6 to the blade tip lightning receptor 4 and the problem lightning receptor 5 through the connector 13, thereby reducing maintenance time, improving maintenance efficiency, and reducing maintenance costs.

[0073] Specifically, the connecting member 13 includes a connecting seat 1301, a boss 1302 and a through hole 1303. The connecting seat 1301 is a cylinder. The boss 1302 is arranged at one end of the connecting seat 1301. The center lines of the connecting seat 1301 and the boss 1302 are coaxial. The connecting seat 1301 is used to connect the problematic lightning rod 5 or the blade tip lightning rod 4. The boss 1302 is used to crimp the repair piece 6. The through hole 1303 is arranged in the axial direction of the connecting seat 1301 and the boss 1302.

[0074] The through hole 1303 is arranged in the axial direction of the connecting seat 1301 and the boss 1302, so that the connecting seat 1301 is a hollow cylindrical structure, which can be put on the problematic lightning rod 5 or the blade tip lightning rod 4 to ensure close contact and good electrical connection. The boss 1302 is used to crimp the repair piece 6, which expands the contact area between the connector 13 and the repair piece 6, ensuring a reliable connection between the repair piece 6 and the problematic lightning rod 5 or the blade tip lightning rod 4, and has a good conductive effect.

[0075] The arrangement has a simple structure, is easy to process, can improve maintenance efficiency and reliability, and has wide applicability.

[0076] Preferably, the connection between the connecting seat 1301 and the boss 1302 is smoothly transitioned.

[0077] The smooth transition connection can ensure that the conductive path between the connection base 1301 and the boss 1302 is smoother, thereby reducing resistance.

[0078] This setting can reduce energy loss during current transmission, improve conductivity, and ensure that lightning current can be quickly transmitted to the ground.

[0079] Preferably, the thickness of the boss 1302 does not exceed 2 mm.

[0080] The thickness of the boss 1302 does not exceed 2 mm, which can reduce its protruding portion on the blade surface, making installation and disassembly more convenient; the thinner boss 1302 can reduce the overall weight of the connector 13.

[0081] In the maintenance process, the smaller thickness of the boss 1302 can reduce interference with the blade surface, improve the efficiency of installation and disassembly, and reduce the weight to reduce the burden on the blade structure, thereby improving the operating efficiency and safety of the blade.

[0082] Specifically, the connecting piece 13 is connected to the problematic lightning receptor 5 by welding, riveting, screwing or threading.

[0083] Specifically, the through hole 1303 is connected to the problematic lightning receptor 5 by interference fit.

[0084] Specifically, in step S3 , the patch 6 can be made into a prefabricated part first, and then the prefabricated part is bonded to the blade shell 1 by the adhesive 9 , or the patch 6 can be directly bonded to the blade shell 1 by the adhesive 9 .

[0085] Whether using prefabricated parts or direct bonding, reliable conductive connections can be ensured between the patch 6 and the blade tip lightning receptor 4, and between the patch 6 and the problematic lightning receptor 5, ensuring smooth conduction of lightning current. Using prefabricated parts for repair can compensate for surface defects in the blade shell 1. By processing the surface defects of the blade shell 1 into a standard shape, the installation of prefabricated parts is facilitated, the repair efficiency is improved, and the impact of surface defects on the bonding effect of the patch 6 is reduced. Direct bonding can achieve rapid repairs, especially when there are no defects on the surface of the blade shell 1. The effect is obvious. Through bonding with adhesive 9, the connection strength between the patch 6 and the blade shell 1 is improved and can withstand external loads such as wind. Both prefabricated parts and direct bonding make the installation of the patch 6 easier, reduce the complexity of on-site operations, make the connection between the patch 6 and the blade shell 1 more stable, and reduce failures caused by loose connections.

[0086] This setting can ensure good conductivity between the repair piece 6 and the blade tip lightning rod 4, and between the repair piece 6 and the problem lightning rod 5. It can solve various surface conditions of the blade shell 1 during the actual repair process, improve mechanical strength, simplify the installation process, enhance durability, and is easy to inspect and maintain. Through reasonable design and connection methods, it can minimize the impact on blade performance and improve the reliability and service life of the wind turbine blade lightning protection system.

[0087] Specifically, the steps for making the patch 6 preform are as follows: first place the patch 6 on the mold, lay fiberglass cloth 7 on top of it, lay padding cloth 8 on both sides to ensure a smooth surface, establish a vacuum environment, perform resin infusion, heat and cure, and then demold to obtain the patch 6 preform.

[0088] The mechanical strength of the patch 6 is enhanced by the glass fiber cloth 7, ensuring the stability of the patch 6 under various weather conditions. The padding cloth 8 ensures the flatness of the surface, improves the surface quality of the patch 6, and reduces wind resistance. Through resin curing, the connection between the patch 6 and the glass fiber cloth 7 is more stable, reducing failures caused by loose connections. The production of prefabricated parts makes the installation of the patch 6 easier and reduces the complexity of on-site operations.

[0089] The prefabricated structure ensures that the patch 6 has good mechanical strength, electrical conductivity, and surface quality, making the connection between the patch 6 and the blade shell 1 more reliable. The prefabricated design not only simplifies the installation process and improves durability and adaptability, but is also cost-effective and easy to inspect and maintain.

[0090] Specifically, in step S3 , the width of the glass fiber cloth 7 is greater than the width of the repair piece 6 .

[0091] The width of the fiberglass cloth 7 is greater than that of the patch 6, ensuring adequate support at the edges of the patch 6 and improving its mechanical strength. The portion of the fiberglass cloth 7 that extends beyond the patch 6 provides additional tensile strength, preventing the patch 6 from tearing or breaking during use and ensuring a smoother surface during the resin curing process, reducing voids and bubbles.

[0092] This arrangement can significantly improve the mechanical strength and surface quality of the patch 6 by ensuring that the width of the glass fiber cloth 7 is greater than the width of the patch 6, making the connection between the patch 6 and the blade shell 1 more reliable.

[0093] Specifically, in step S3 , after the patch 6 is directly bonded to the blade shell 1 , a sealant 10 is applied to the outer surface and edge of the patch 6 to protect the transition.

[0094] The sealant 10 can prevent moisture from invading the gap between the patch 6 and the blade shell 1, avoid corrosion and oxidation, make the surface smoother, protect the patch 6 from environmental factors, extend the service life of the patch 6, enhance the impact resistance of the edge of the patch 6, and prevent the edge from being damaged.

[0095] This arrangement significantly improves the protective performance of the patch 6 by applying sealant 10 to the outer surface and edges of the patch 6, ensuring its durability and stability in harsh environments. The application of sealant 10 not only provides waterproofing and moisture resistance, but also improves surface quality and simplifies maintenance.

[0096] Specifically, in step S5, the resistance value between the blade tip lightning receptor 4 and the blade root lightning conductor 2 is not greater than 50 mΩ.

[0097] A resistance value of no more than 50 mΩ ensures the continuity of the conductive path from the blade tip lightning rod 4 to the blade root lightning conductor 2. The lightning current can be smoothly conducted from the blade tip to the ground, ensuring the effectiveness of the system. The low resistance value can reduce energy loss during current transmission and prevent heating and failure caused by excessive resistance.

[0098] This arrangement can significantly improve the conductivity, reliability and safety of the wind turbine blade lightning protection system by ensuring that the resistance value between the blade tip lightning receptor 4 and the blade root lightning conductor 2 is no more than 50 mΩ.

[0099] Example 1

[0100] like Figure 1 、 2As shown in FIG3 , the utility model proposes a method for repairing a lightning conductor 2 of a wind turbine blade, comprising a blade shell 1 , a lightning conductor 2 , a blade body lightning rod 3 , a blade tip lightning rod 4 , a patch 6 , a glass fiber cloth 7 , a padding cloth 8 , an adhesive 9 , and a sealant 10 .

[0101] The conduction is restored mainly by providing a repair piece 6 on the outer surface of the blade shell 1 in the fractured area.

[0102] The repair method of the lightning conductor 2 includes the following: 1. By measuring the resistance of the blade tip lightning rod 4 and the blade body lightning rod 3 respectively, the resistance value from the blade body lightning rod 3 to the blade root lightning rod 2 is measured to determine the broken location area of ​​the lightning conductor 2. 2. After the area is determined, the outer surface coating of the blade shell 1 in this area is polished, and after polishing and cleaning, the repair piece 6 is bonded. One end of the repair piece 6 in the length direction is directly connected to the blade tip lightning rod 4, and the other end is directly connected to the problem lightning rod 5. The connection form can be riveted or screwed. 3. After the repair is completed, restore the surface coating of this area of ​​the blade shell 1. 4. Measure the resistance from the blade tip lightning rod 4 to the blade root lightning rod 2, check the resistance value to determine whether the lightning protection system has restored conductivity.

[0103] The patch 6 can be a metal mesh or a metal foil.

[0104] One method of bonding patch 6 to blade shell 1 is as follows: 1. Patch 6 and fiberglass cloth 7 are prefabricated into one piece using resin infusion in a blade mold. The specific prefabrication steps are as follows: Place patch 6 on the mold, then lay fiberglass cloth 7 over patch 6. The width of fiberglass cloth 7 should be greater than that of patch 6. To ensure surface flatness, place some padding 8 on both sides of fiberglass cloth 7 during prefabrication. A vacuum is then established for resin infusion. After heating, curing, and demolding, the prefabricated patch 6 is obtained. 2. The prefabricated patch 6 is bonded to the outside of blade shell 1 using adhesive 9.

[0105] Another way to bond the patch 6 to the blade shell 1 is as follows: 1. Directly bond the patch 6 to the blade shell 1 using adhesive 9. 2. Then apply sealant 10 to the outer surface and edge of the patch 6 to protect the transition.

[0106] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A lightning protection assembly for wind turbine blade maintenance, characterized in that: The invention comprises a patch (6), wherein the patch (6) is arranged on the outside of the blade shell (1), one end of the patch (6) is connected to the blade tip lightning receptor (4), and the end of the patch (6) away from the blade tip lightning receptor (4) is connected to the problem lightning receptor (5).

2. The lightning protection assembly for wind turbine blade maintenance according to claim 1, characterized in that: The two ends of the patch (6) are folded into a first connecting portion (11) and a second connecting portion (12), respectively; the first connecting portion (11) is used to connect to the blade tip lightning receptor (4), and the second connecting portion (12) is used to connect to the problematic lightning receptor (5).

3. The lightning protection assembly for wind turbine blade maintenance according to claim 2, characterized in that: The connection surface area between the first connection portion (11) and the blade tip lightning receptor (4), and the connection surface area between the second connection portion (12) and the problematic lightning receptor (5) are both not less than the longitudinal cross-sectional area of ​​the patch (6).

4. The lightning protection assembly for wind turbine blade maintenance according to claim 1, characterized in that: The patch (6) and the blade tip lightning receptor (4), and the patch and the problematic lightning receptor (5) are connected by rivet riveting or screw fastening.

5. The lightning protection assembly for wind turbine blade maintenance according to claim 1, characterized in that: The preform made of the patch (6) is bonded to the blade shell (1) via an adhesive (9), or the patch (6) is directly bonded to the blade shell (1) via the adhesive (9).

6. The lightning protection assembly for wind turbine blade maintenance according to claim 5, characterized in that: The preform of the patch (6) is made by a vacuum infusion molding process.

7. The lightning protection assembly for wind turbine blade maintenance according to claim 5, characterized in that: The patch (6) is bonded to the blade shell (1), and a sealant (10) is applied to the outer surface and edge of the patch (6) to protect the transition.

8. The lightning protection assembly for wind turbine blade maintenance according to claim 1, characterized in that: The patch (6) is a metal mesh or a metal foil, the thickness of the patch (6) does not exceed 1 mm, and the width ranges from 100 to 300 mm.

9. The lightning protection assembly for wind turbine blade maintenance according to claim 1, characterized in that: The patch (6) and the blade tip lightning receptor (4), and the patch (6) and the problematic lightning receptor (5) are connected via a connector (13).

10. The lightning protection assembly for wind turbine blade maintenance according to claim 9, characterized in that: The connecting member (13) includes a connecting seat (1301), a boss (1302) and a through hole (1303); the connecting seat (1301) is a cylinder; the boss (1302) is arranged at one end of the connecting seat (1301); the center lines of the connecting seat (1301) and the boss (1302) are coaxial; the connecting seat (1301) is used to connect the problematic lightning receptor (5) or the blade tip lightning receptor (4); the boss (1302) is used to press the repair piece (6); and the through hole (1303) is arranged in the axial direction of the connecting seat (1301) and the boss (1302).

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