Method of manufacturing a wind turbine blade comprising a flexible glass membrane and related wind turbine blade

Abstract

The present disclosure relates to a method for manufacturing a wind turbine blade (22). The wind turbine blade (22) has a length in a longitudinal direction from a root end (217) to a tip end (215) and comprises a wind turbine blade shell (222) having an aerodynamic profile with a pressure side (224) and a suction side (226). One or more flexible glass membranes (51, 61) are arranged in the wind turbine blade (22). The present disclosure also relates to a wind turbine blade (22) comprising one or more flexible glass membranes (51, 61).

Description

Technical Field

[0001] This disclosure relates to wind turbine blades, and more specifically, to wind turbine blades comprising one or more flexible glass membranes. This disclosure further relates to methods for manufacturing wind turbine blades comprising flexible glass membranes. Background Technology

[0002] Modern wind turbines are commonly used to supply electricity to the power grid. This type of wind turbine generally consists of a tower and a rotor mounted on the tower. The rotor, typically including a hub and multiple blades, is configured to rotate under the influence of wind on the blades. This rotation generates torque, which is typically transmitted via the rotor shaft to a generator, either directly (“direct drive”) or through a gearbox. In this way, the generator produces electricity that can be supplied to the power grid.

[0003] The wind turbine hub can be rotatably connected to the front of the nacelle. The wind turbine hub can be connected to the rotor shaft, and the rotor shaft can be rotatably mounted in the nacelle using one or more rotor shaft bearings arranged in a frame within the nacelle. The nacelle is a shell arranged on top of the wind turbine tower, which may contain and protect the gearbox (if present) and generator (if not located outside the nacelle), as well as other components such as power converters and auxiliary systems, depending on the wind turbine.

[0004] Wind turbine blades extract kinetic energy from the wind and convert it into rotational kinetic energy. To extract even more energy from the wind, the length of blades in modern wind turbines is constantly increasing. As a result, higher physical loads are introduced into the blades and related components. Therefore, long blades need to remain structurally effective to withstand all loads while remaining as lightweight as possible to facilitate logistics and installation. Specifically, they need to withstand both extreme and fatigue loads while minimizing the weight and cost of the blades.

[0005] Wind turbine blades generally consist of a shell body with aerodynamic profiles having pressure and suction sides. The geometry of the aerodynamic profile is optimized to maximize the annual power generation of the wind turbine for a given wind speed distribution.

[0006] Different materials have been used in the manufacture of wind turbine blades. These materials need to combine necessary structural properties (e.g., high strength-to-weight ratio) with relatively low cost. Furthermore, the material used for the shell body needs to have the ability to be shaped into the airfoil shape required for sufficient aerodynamic performance. Fiber-reinforced polymers, such as glass fiber or carbon fiber reinforced materials, have typically been used. Therefore, the blade shell is usually manufactured by arranging glass and / or carbon fiber laminates in a mold. Resin is typically infused and subsequently cured to form a laminate, which constitutes the wind turbine blade shell. Alternatively, or in combination with the aforementioned resin infusion process, pre-impregnated fibers, i.e., prepreg composites, can also be used in the manufacture of wind turbine blades.

[0007] Wind turbine blade shells are typically relatively lightweight and structurally insufficient to withstand all bending moments and other loads acting on the blades during operation. To improve structural properties such as stiffness and strength, blades are often reinforced with structural members, such as one or more beam caps on the suction and pressure sides of the blade shell, with shear webs connecting them. Beam caps are also typically made using fiber-reinforced materials. Carbon fiber materials are often used for beam caps, especially due to their structural properties. In addition, in some cases, pultruded sheets are used to manufacture beam caps.

[0008] The fibers arranged in the fiber-reinforced composite that constitutes the laminated blade shell and structural reinforcing members are typically aligned according to a predetermined direction. In some cases, all fibers may be arranged in the same direction, i.e., unidirectional arrangement; while in others, the fibers may extend in two perpendicular directions, i.e., bidirectional arrangement. In still other examples, a triaxial arrangement may also be used. The orientation of the fibers can impose some limitations on the structural characteristics of the wind turbine blade. In particular, certain directions may be limited to withstand certain loads, but this may result in reduced strength in other directions.

[0009] Durability is another critical aspect to consider when designing and manufacturing wind turbine blades throughout their lifespan. Wind turbine blades, particularly the leading edge region, are known to be susceptible to erosion due to impacts from raindrops, hail, or particles. The tip region of the blade, in particular, is especially vulnerable to erosion due to its high linear velocity. Furthermore, the increased blade length in modern wind turbines, as already mentioned, leads to higher tip velocities, exacerbating erosion and increasing the rate of blade degradation. Specifically, offshore wind turbines, typically constrained by less noise, can be biased towards even higher tip velocities, thus increasing the erosion effect.

[0010] Eroded blades exhibit irregular surfaces, which can significantly impact the long-term structural stability of wind turbine blades and the airflow around them—that is, the aerodynamic behavior of the wind turbine blades. Therefore, roughened blades generate less lift and more drag for a given airflow, reducing the power produced by the wind turbine. Correspondingly, blades with eroded leading edges can cause a non-negligible reduction in annual power generation (AEP). These reductions may be exacerbated by the fact that the main contributions to the rotor blade aerodynamic efficiency come from the blade tip region and the mid-span portion of the blade (which is the most erosion-sensitive area due to the high speeds present).

[0011] To withstand high tip velocities and protect the leading edge from erosion, known solutions include using so-called leading-edge protection (LEP) systems to coat and / or cover the leading edge of wind turbine blades. Known methods of implementing such LEP systems include using tape or protective polymer-based coatings, such as paint, applied to the leading-edge area of ​​the wind turbine blade. In other cases, prefabricated protective covers are applied to the leading edge. In the latter case, polymer-based prefabricated protective covers have been commercially available for erosion prevention, while metal-based protective covers have been studied.

[0012] However, commonly recommended LEP systems exhibit certain shortcomings. In particular, tapes, polymer-based coatings, and / or polymer-based shields show only limited resistance to erosion when subjected to the high kinetic energy of airborne particles or raindrops, especially considering the high blade tip velocities experienced by very long blades, such as those used in offshore wind turbines. Therefore, wear of the polymer-based coatings or shields is observed. Furthermore, existing solutions for attaching and bonding the aforementioned polymer-based solutions are not durable enough, which can cause the LEP system to detach from the blade leading edge. Consequently, these solutions fail to provide effective erosion protection for the entire service life of the blade (e.g., at least 20 years), leading to frequent inspection, maintenance, and / or replacement operations. These maintenance operations are time-consuming, difficult, and therefore expensive. This is especially true for offshore wind turbines. Furthermore, the direct loss of power generation stems from the downtime associated with these maintenance operations, which also affects the annual power generation (AEP) of the wind turbine.

[0013] These also present certain drawbacks for metal-based LEP systems. In particular, the problems stem from the associated lightning protection, i.e., protecting wind turbine blades from lightning strikes. Therefore, the structural integrity of the blades can be compromised by the use of metal components in the LEP system. Furthermore, as described, wind turbine blades primarily consist of a shell formed from composite materials (e.g., glass fiber composites). Achieving a sufficiently strong bond between the metal LEP system and the composite material can be particularly difficult. The metal-to-composite interface bonding can degrade rapidly, causing the metal LEP to detach from the outer surface of the wind turbine blade. Additionally, metal-based LEP systems are susceptible to corrosion problems, especially when used in offshore environments, and can significantly increase the weight of the wind turbine blades.

[0014] This disclosure provides examples of methods for manufacturing wind turbine blades that at least partially overcome some of the shortcomings of existing wind turbine blades. Corresponding wind turbine blades are also provided by this disclosure. Summary of the Invention

[0015] In a first aspect, a method for manufacturing a wind turbine blade is provided. The wind turbine blade has a length in a longitudinal direction from its root end to its tip end and includes a wind turbine blade shell having an aerodynamic profile with a pressure side and a suction side. One or more flexible glass membranes are arranged in the wind turbine blade.

[0016] According to this first aspect, a wind turbine blade comprising a flexible glass membrane is provided. The flexible glass membrane exhibits properties suitable for improving the performance of the wind turbine blade. Specifically, the flexible glass membrane exhibits electrical and mechanical properties sufficient to enhance the structural and durability characteristics of the wind turbine blade, as will be shown in more detail below. In some examples, the flexible glass may be based on borosilicate glass.

[0017] In one example, the wind turbine blade shell may define a leading edge, and the method may include a protective element arranged to cover at least a portion of the leading edge. The protective element may include at least one flexible glass membrane and may extend along at least a portion of the length of the wind turbine blade.

[0018] In this example, the mechanical flexibility and rigidity of the glass film are used to protect the leading edge region of the wind turbine blade, thus providing a highly corrosion-resistant leading edge protection system. As mentioned above, wind turbine blade manufacturers are increasingly concerned about the erosion of the blade leading edge. This is especially true as wind turbine blades become increasingly longer (leading to higher tip velocities, which increase damage caused by, for example, water droplets at the leading edge). Even though several leading edge protection (LEP) systems have been used in the past, they have exhibited certain limitations due to their limited abrasion resistance, their electrical behavior, and / or the need for frequent maintenance. In particular, the maintenance of leading edge protection systems can be particularly cumbersome in some applications, such as offshore wind turbines.

[0019] By using flexible glass membranes, a LEP (Low-Effect Power Generation) system can be provided that requires less maintenance and offers a longer service life, while enabling wind turbines to operate at higher terminal speeds, thus increasing power density. In effect, operating at higher terminal speeds allows the generator rotor to rotate at higher speeds, thereby increasing generator power. Flexible glass membranes exhibit very high hardness values ​​and are highly resistant to corrosion and abrasion because they can absorb kinetic energy from, for example, raindrops, thus increasing the durability of the protection system.

[0020] The corrosion protection provided by such glass membranes is comparable to that offered by some LEP systems that incorporate metallic materials. However, unlike metal shields, another advantage of glass membranes lies in their electrical insulation properties. In fact, the use of glass membranes does not interfere with existing lightning protection systems (LPS), thus avoiding undesirable effects during lightning strikes. Furthermore, flexible glass membranes are relatively lightweight, especially compared to metal-based LEP systems, so the overall weight of the blades does not increase significantly.

[0021] The flexibility of the glass membrane allows for a very small bending radius, which enables the glass membrane to conform to the curved shape of the blade shell along the length of the blade at the leading edge. In other words, the flexible glass membrane can be bent to the radius of the blade's leading edge. This flexibility provides different options for the application of the glass membrane, as will be described in detail below with reference to different examples of this disclosure.

[0022] In another aspect of this disclosure, the wind turbine blade shell may include a plurality of fiber stacks and at least one of the flexible glass films may be arranged together with the fiber stacks.

[0023] According to this example, another property of the flexible glass membrane can advantageously be utilized to further improve the characteristics of the wind turbine blade. In this case, the structural and mechanical properties of the glass membrane can be used to optimize the structural behavior of the blade, enabling it to withstand operating loads for a given acceptable weight and provide the desired mechanical properties while maintaining manufacturability. Methods involving the use of fibers (e.g., glass fibers or carbon fibers) to obtain fiber-reinforced polymers are well known. In such methods, fiber laminates are typically placed in a mold and infused with resin, which, upon curing, forms a blade shell or blade shell portion. Various variations of such manufacturing methods are well known to those skilled in the art, and therefore further details are not considered necessary.

[0024] Similarly, the ferrule cap or main laminate of a wind turbine blade can be manufactured in a similar manner. In such cases, carbon fiber is preferably used due to its mechanical properties. Alternatively, the ferrule cap can also be made using fibers pultruded from resin materials, as is known to those skilled in the art.

[0025] In any case, the arrangement of fibers used to manufacture the blade shell and / or beam cap (or any other laminate in a wind turbine blade) is at least partially defined by the orientation of the fibers. In practice, fibers can be arranged in a single direction, such as along the longitudinal axis of the wind turbine, in a so-called unidirectional arrangement, or in a bidirectional arrangement, in which fibers may be provided in a vertically oriented arrangement. Furthermore, arrangements involving more directions, such as triaxial arrangements, are also known. However, in all these cases, the resulting behavior and structural properties of the laminate are at least partially determined by the fiber orientation.

[0026] Flexible glass membranes are not like this. Therefore, flexible glass membranes exhibit isotropic mechanical and structural properties, meaning they do not have a preferred orientation. Thus, the combination of flexible glass membranes with fiber laminates allows for improved handling of the operating loads experienced by wind turbine blades. To this end, the method according to this example involves arranging several such flexible glass membranes in a manner integrated with currently existing laminates or panels.

[0027] The laminate can correspond to the blade shell and / or beam cap of a wind turbine blade. Furthermore, the quantity and location of the flexible glass membrane can be optimized to account for the magnitude and orientation of loads at different locations on the wind turbine blade. In practice, a non-uniform distribution of the flexible glass membrane can be provided; for example, a larger number of membranes can be placed in certain areas of the wind turbine blade.

[0028] In another aspect of the invention, a wind turbine blade is provided. The wind turbine blade has a length in the longitudinal direction from its root end to its tip end and includes a wind turbine blade shell having an aerodynamic profile with a pressure side and a suction side. The wind turbine blade includes one or more flexible glass membranes.

[0029] Based on this, wind turbine blades with improved structural and mechanical properties were obtained. Some advantages associated with using such glass membranes have already been described with reference to the methods for manufacturing such blades, and therefore will not be repeated here.

[0030] In an exemplary wind turbine blade, the wind turbine blade shell may define a leading edge, and the wind turbine blade may further include a protective element comprising a flexible glass membrane. The protective element may be configured to cover at least a portion of the leading edge and to extend along at least a portion of the length of the wind turbine blade, particularly for extending at least one-third of the length of the wind turbine blade.

[0031] According to this aspect, a blade with improved resistance to leading-edge erosion can be provided. Reduced maintenance and / or operation at higher speeds can be achieved, thus improving the overall performance of the resulting wind turbine. This aspect of the example has been addressed in the discussion of related methods, and therefore reference should be made to the preceding paragraphs. Furthermore, details and advantages of the wind turbine blade according to this aspect will be described in detail below with reference to specific examples.

[0032] In yet another example, a different wind turbine blade is provided. In this case, the wind turbine blade includes a blade shell with fiber layers and / or stacks. A flexible glass membrane is arranged below and / or above the fiber stacks. In particular, the flexible glass membrane may be arranged to form the outermost layer of the shell.

[0033] As explained by the associated method, wind turbine blades with flexible glass membranes integrated into a laminated structure can exhibit enhanced structural performance.

[0034] It is worth noting that flexible glass films can be manufactured as single-layer or multi-layer films. In the latter case, a flexible glass film may comprise multiple layers bonded together by, for example, an adhesive. A multi-layer arrangement may be preferred for the manufacturing process of the glass film itself and / or for providing the glass film with specific properties (such as a specific bending radius or UV resistance). However, throughout this disclosure, both flexible glass films comprising a single layer and flexible glass films comprising multiple layers will simply be referred to as flexible glass films. In some examples, multiple such glass films may be employed, each comprising a single-layer or multi-layer internal arrangement. Attached Figure Description

[0035] The following description, with reference to the accompanying drawings, will illustrate a non-limiting example of this disclosure, in which: Figure 1 A perspective view of a wind turbine based on an example is shown; Figure 2 A detailed interior view of the nacelle of a wind turbine, based on an example, is shown. Figure 3A wind turbine blade assembly is schematically shown according to an example; Figure 4 The internal structure of an example of a wind turbine blade is schematically shown; Figure 5 An example of a protective element comprising a flat, flexible glass film is shown schematically; Figure 6 An example of a protective element comprising a pre-formed flexible glass film is schematically shown; Figure 7 A schematic cross-sectional view of an example wind turbine blade including protective elements is shown; Figures 8A-8C An example of a method for manufacturing a relatively rigid protective element is schematically shown, along with a cross-sectional view of a wind turbine including such a protective element. Figure 9 The illustration schematically shows the leading edge region of a wind turbine blade, which includes a sealant at the interface between the protective element and the blade shell surface, according to an example. Figure 10 An example of a protective element including a narrowed end is shown schematically; Figure 11 The steps in a method for manufacturing a wind turbine blade shell comprising one or more flexible glass membranes are illustrated schematically according to an example. Detailed Implementation

[0036] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. The various examples are provided by way of explanation only and are not intended to be limiting. Indeed, it will be apparent to those skilled in the art that various modifications and variations may be made to this disclosure. For example, features shown or described in part as one embodiment may be used with another embodiment to produce yet another embodiment. Therefore, it is intended that this disclosure cover such modifications and variations within the scope of the appended claims and their equivalents.

[0037] Figure 1This is a perspective view of an example wind turbine 10. In this example, the wind turbine 10 is a horizontal axis wind turbine. Alternatively, the wind turbine 10 may be a vertical axis wind turbine. In this example, the wind turbine 10 includes a tower 15 extending from a support system 14 on the ground 12, a nacelle 16 mounted on the tower 15, and a rotor 18 coupled to the nacelle 16. The rotor 18 includes a rotatable hub 20 and at least one rotor blade 22 coupled to and extending outward from the hub 20. In this example, the rotor 18 has three rotor blades 22. In an alternative embodiment, the rotor 18 includes more or fewer than three rotor blades 22. The tower 15 may be made of tubular steel to define a cavity between the support system 14 and the nacelle 16. Figure 1 (Not shown in the image). In an alternative embodiment, tower 15 is any suitable type of tower with any suitable height. According to one alternative, the tower can be a hybrid tower, comprising sections made of concrete and sections made of tubular steel. The tower can also be a partial or full lattice tower.

[0038] Rotor blades 22 are spaced around hub 20 to facilitate rotation of rotor 18 so that kinetic energy can be converted from wind into usable mechanical energy and subsequently into electrical energy. Rotor blades 22 are coupled to hub 20 by connecting blade root portions 24 to multiple load transfer regions 26. Load transfer regions 26 may have hub load transfer regions and blade load transfer regions (neither of which are located in the hub load transfer region 26). Figure 1 (As shown in the image). The load induced on the rotor blades 22 is transferred to the hub 20 via the load transfer area 26.

[0039] In the example, rotor blade 22 may have a length ranging from about 15 meters (m) to about 90 meters (m) or greater. Rotor blade 22 may have any suitable length that enables wind turbine 10 to function as described herein. For example, non-limiting examples of blade length include 20 meters or less, 37 meters, 48.7 meters, 50.2 meters, 52.2 meters, or lengths greater than 91 meters or even greater than 100 meters. When wind strikes rotor blade 22 from wind direction 28, rotor 18 rotates about rotor axis 30. As rotor blade 22 rotates and is subjected to centrifugal force, rotor blade 22 is also subjected to various forces and torques. Therefore, rotor blade 22 may deflect and / or rotate from a neutral or undeflected position to a deflected position.

[0040] Furthermore, the pitch angle of the rotor blade 22, i.e., the angle that determines the orientation of the rotor blade 22 relative to the wind direction, can be changed by the pitch system 32 to control the load and power generated by the wind turbine 10 by adjusting the angular position of at least one rotor blade 22 relative to the wind vector. The pitch axis 34 of the rotor blade 22 is shown. During the operation of the wind turbine 10, the pitch system 32 can specifically change the pitch angle of the rotor blade 22 to reduce the angle of attack of the rotor blade (partially), which is beneficial for reducing the speed and / or beneficial for the stall of the rotor 18.

[0041] In this example, the blade pitch of each rotor blade 22 is individually controlled by the wind turbine controller 36 or by the pitch control system 80. Alternatively, the blade pitch of all rotor blades 22 can be simultaneously controlled by the control system.

[0042] Furthermore, in this example, when the wind direction 28 changes, the yaw direction of the nacelle 16 can be rotated about the yaw axis 38 to position the rotor blades 22 relative to the wind direction 28.

[0043] In this example, the wind turbine controller 36 is shown as centralized within the nacelle 16; however, the wind turbine controller 36 can be a distributed system located at various points on the wind turbine 10, on the support system 14, within the wind farm, and / or at a remote control center. The wind turbine controller 36 includes a processor 40 configured to perform the methods and / or steps described herein. Furthermore, many other components described herein include processors.

[0044] As used herein, the term "processor" is not limited to integrated circuits referred to in the art as computers, but broadly refers to controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application-specific integrated circuits (ASICs), and other programmable circuits, and these terms are used interchangeably herein. It should be understood that processors and / or control systems may also include memory, input channels, and / or output channels.

[0045] Figure 2This is an enlarged cross-sectional view of a portion of a wind turbine 10. In this example, the wind turbine 10 includes a nacelle 16 and a rotor 18 rotatably coupled to the nacelle 16. More specifically, the hub 20 of the rotor 18 is rotatably coupled to a generator 42 located within the nacelle 16 via a main shaft 44, a gearbox 46, a high-speed shaft 48, and a coupling 50. In this example, the main shaft 44 is at least partially coaxial with the longitudinal axis (not shown) of the nacelle 16. The rotation of the main shaft 44 drives the gearbox 46, which in turn drives the high-speed shaft 48 by converting the relatively slow rotational motion of the rotor 18 and the main shaft 44 into a relatively fast rotational motion of the high-speed shaft 48. The high-speed shaft 48 is connected to the generator 42 by means of the coupling 50 for generating electrical energy. Furthermore, a transformer 90 and / or suitable electronic equipment, switches, and / or inverters may be arranged in the nacelle 16 to convert electrical energy generated by the generator 42 at voltages ranging from, for example, 400V to 1000V into electrical energy at medium voltages (e.g., 10-35kV). The offshore wind turbine may, for example, have a generator voltage between 650V and 3500V, while the transformer voltage may, for example, be between 30kV and 70kV. The electrical energy is conducted from the nacelle 16 to the tower 15 via power cables.

[0046] The gearbox 46, generator 42, and transformer 90 may be supported by the main support structure frame of the nacelle 16 (optionally embodied as main frame 52). The gearbox 46 may include a gearbox housing connected to the main frame 52 via one or more torque arms 103. In this example, the nacelle 16 also includes a main front support bearing 60 and a main rear support bearing 62. Furthermore, the generator 42 may be mounted to the main frame 52 via decoupling support devices 54, particularly to prevent vibrations of the generator 42 from being introduced into the main frame 52 and thus becoming a source of noise emission.

[0047] Optionally, the main frame 52 is configured to bear the weight of the components of the nacelle 16 and the rotor 18, as well as the total loads caused by wind and rotational loads, and further introduce these loads into the tower 15 of the wind turbine 10. The rotor shaft 44, generator 42, gearbox 46, high-speed shaft 48, coupling 50, and any associated fastening, support, and / or fixing devices (including, but not limited to, the main frame 52, the front support bearing 60, and the rear support bearing 62) are sometimes referred to as the drivetrain 64.

[0048] In some examples, the wind turbine can be a direct-drive wind turbine without gearbox 46. In a direct-drive wind turbine, generator 42 operates at the same speed as rotor 18. Therefore, it typically has a much larger diameter than a wind turbine with gearbox, or a generator in a wind turbine with gearbox 46 used to provide a similar amount of power.

[0049] The nacelle 16 may also include a yaw drive mechanism 56, which can be used to rotate the nacelle 16 and thus the rotor 18 about the yaw axis 38 to control the attitude of the rotor blades 22 relative to the wind direction 28. To properly position the nacelle 16 relative to wind direction 28, the nacelle 16 may also include at least one meteorological measurement system 58, which may include a wind vane and an anemometer. The meteorological measurement system 58 may provide information to the wind turbine controller 36, including wind direction 28 and / or wind speed. In this example, the pitch system 32 is at least partially arranged as a pitch assembly 66 in the hub 20. The pitch assembly 66 includes one or more pitch drive systems 68 and at least one sensor 70. Each pitch drive system 68 is coupled to a corresponding rotor blade 22. Figure 1 (As shown in the image) is used to modulate the pitch angle of the rotor blades 22 along the pitch axis 34. Figure 2 Only one of the three pitch drive systems 68 is shown in the image.

[0050] In this example, the pitch assembly 66 includes at least one pitch bearing 72, which is coupled to the hub 20 and the corresponding rotor blades 22. Figure 1 (As shown in the image) is used to rotate the corresponding rotor blades 22 about the pitch axis 34. The pitch drive system 68 includes a pitch drive motor 74, a pitch drive gearbox 76, and a pitch drive pinion 78. The pitch drive motor 74 is coupled to the pitch drive gearbox 76 such that the pitch drive motor 74 applies mechanical force to the pitch drive gearbox 76. The pitch drive gearbox 76 is coupled to the pitch drive pinion 78 such that the pitch drive pinion 78 is rotated by the pitch drive gearbox 76. The pitch bearing 72 is coupled to the pitch drive pinion 78 such that rotation of the pitch drive pinion 78 causes rotation of the pitch bearing 72.

[0051] The pitch drive system 68 is coupled to the wind turbine controller 36 for adjusting the pitch angle of the rotor blades 22 upon receiving one or more signals from the wind turbine controller 36. In this example, the pitch drive motor 74 is any suitable motor driven by an electric and / or hydraulic system that enables the pitch assembly 66 to function as described herein. Alternatively, the pitch assembly 66 may include any suitable structure, configuration, arrangement, and / or components, such as, but not limited to, hydraulic cylinders, springs, and / or servo mechanisms. In some embodiments, the pitch drive motor 74 is driven by energy extracted from the rotational inertia of the hub 20 and / or stored energy (not shown) in components that supply energy to the wind turbine 10.

[0052] The pitch assembly 66 may also include one or more pitch control systems 80 for controlling the pitch drive system 68 according to control signals from the wind turbine controller 36 under specific priority conditions and / or during rotor 18 overspeed. In this example, the pitch assembly 66 includes at least one pitch control system 80 communicatively coupled to a corresponding pitch drive system 68 for controlling the pitch drive system 68 independently of the wind turbine controller 36. In this example, the pitch control system 80 is coupled to the pitch drive system 68 and the sensor 70. During normal operation of the wind turbine 10, the wind turbine controller 36 can control the pitch drive system 68 to adjust the pitch angle of the rotor blades 22.

[0053] According to one embodiment, a power generator 84 (e.g., including batteries and capacitors) is arranged at or within hub 20 and coupled to sensor 70, pitch control system 80, and pitch drive system 68 to provide a power source to these components. In this example, power generator 84 provides a continuous power source to pitch assembly 66 during operation of wind turbine 10. In an alternative embodiment, power generator 84 provides power to pitch assembly 66 only during power loss events of wind turbine 10. Power loss events may include grid losses or voltage dips, electrical system failures of wind turbine 10, and / or failure of wind turbine controller 36. During power loss events, power generator 84 operates to provide electrical power to pitch assembly 66, enabling pitch assembly 66 to operate during power loss events.

[0054] In this example, the pitch drive system 68, sensor 70, pitch control system 80, cable, and power generator 84 are each positioned within a cavity 86 defined by the inner surface 88 of the hub 20. In an alternative embodiment, the components are positioned relative to the outer surface of the hub 20 and can be directly or indirectly coupled to the outer surface.

[0055] Figure 3 A wind turbine blade 22 according to an example is schematically shown. The wind turbine blade 22 extends longitudinally from a root end 217 to a trailing end 215. The wind turbine blade 22 includes a shell 222 having an outer surface defining a pressure surface and a suction surface, a leading edge 218 and a trailing edge 220, and a load-bearing structure extending longitudinally.

[0056] also, Figure 3 The wind turbine blade 22 shown in this example may include a plurality of protective elements 41 covering at least a portion of the leading edge 218 of the wind turbine blade 22. More specifically, in this example, three protective elements 41 are shown extending in the spanwise direction between a first side edge 411 and a second side edge 412. The protective elements 41 also define a first longitudinal extension edge 421 and a second longitudinal extension edge 422. Figure 3 Not visible in the middle; reference Figure 7 The protective element 41 may extend along at least a portion of the leading edge 218, such as 20-50% of the span of the leading edge 218 of the blade 22. Furthermore, as in... Figure 3 As shown, the protective element 41 may be arranged in the outermost portion of the wind turbine blade 22, that is, in the region of the wind turbine blade 22 that is longitudinally closer to the tip 215 of the wind turbine blade 22. In some cases, the protective element 41 may extend to the tip 215 of the blade, while in other cases, the second side edge 412 of the protective element 41 may be located, for example, a few millimeters or centimeters away from the tip 215.

[0057] In addition, Figure 3 The diagram also schematically shows the leading edge laminate 228 (see also...). Figure 4 Such a leading-edge laminate 228 may also be present in the wind turbine blade 22 and may include a fiber-reinforced laminate comprising multiple fiber stacks. The leading-edge laminate 228 may extend along the length of the leading edge 218 to structurally reinforce that region. In some examples, the leading-edge laminate 228 may extend along substantially the entire length of the blade 22. Although the leading-edge laminate 228 may be arranged to cover at least a portion of the leading edge 218, this element should not be confused with a LEP (Leading Edge Protection) system. Therefore, the purpose of the leading-edge laminate 228 is to structurally reinforce the blade 22 and not necessarily to prevent erosion of the blade shell 222 in the region of the leading edge 218.

[0058] Figure 4This is a schematic cross-sectional view illustrating an example of a wind turbine blade 22, such as a cross-sectional view of the airfoil region of the wind turbine blade 22. The wind turbine blade 22 includes a leading edge 218, a trailing edge 220, a pressure-side shell portion 224, a suction-side shell portion 226, a first beam cap 274, and a second beam cap 276. The wind turbine blade 22 includes a chord 238 between the leading edge 218 and the trailing edge 220. The wind turbine blade 22 includes one or more shear webs 242, such as a leading-edge shear web and a trailing-edge shear web. The shear web 242 may alternatively be a beam box with beam sides (such as trailing-edge beam sides and leading-edge beam sides). The beam caps 274, 276 extending within the blade 22 in a generally spanwise direction may comprise glass fiber, carbon fiber, or a hybrid arrangement of different fibers. The remainder of the shell portions 224, 226 may comprise glass fiber. Beam caps 274 and 276 can be part of the corresponding blade shell portion, either integrally formed therewith or adhered to the corresponding blade shell portion. Furthermore, each shell portion 224 and 226 may include one or more additional beam caps. In some examples, the pressure shell portion 224 and the suction shell portion 226 can be manufactured separately in a separate mold and subsequently bonded, for example, glued together. In other examples, the pressure shell portion 224 and the suction shell portion 226 can be manufactured together in a single mold. Furthermore, in Figure 4 In the example shown, blade 22 may also include a leading edge laminate 228 to structurally reinforce the leading edge 218 region of blade 22.

[0059] Figure 5 An example of a protective element 41 for the leading edge 218 of a wind turbine blade 22 is provided. In this example, the protective element 41 may comprise a substantially planar or flat flexible glass membrane 51. The flexible glass membrane is a thin film with a thickness as low as 50 μm, which allows it to be flexible while retaining glass properties. A method of arranging the protective element 41 may include attaching the flat flexible glass membrane 51 to the outer surface of the wind turbine blade shell 222, covering at least a portion of the leading edge 218, such that the flexible glass membrane 51 conforms to the shape of the wind turbine blade shell 222 at the leading edge 218. In other words, the flat flexible glass membrane 51 may initially be provided in a substantially planar or flat manner, and due to its flexibility, it can be adapted to the shape of the wind turbine blade shell 222 for attachment to the outer surface of the wind turbine blade shell 222 in the region of the leading edge 218.

[0060] More specifically, the initially flat flexible glass membrane 51 can conform to the U-shaped bend defined in the leading edge 218 by the pressure side 224 and suction side 226 of the blade shell 222. Therefore, using such a flat flexible glass membrane 51 results in effective protection of the leading edge 218 from corrosion due to the rigidity characteristics of the membrane. Furthermore, the flat flexible glass membrane 51 can have a thickness in the range of 50 μm or higher, which allows for a reduced bending radius, thus facilitating conforming to the shape of the leading edge 218 region.

[0061] In a variation of this example, instead of a single flat flexible glass membrane 51, multiple flat flexible glass membranes 51 may be provided. In such a case, the flat flexible glass membranes 51 may be pre-bonded, for example, they may be adhered to each other. Subsequently, the provided pre-bonded flat flexible glass membranes 51 may be attached as a single unit to the wind turbine blade housing 222 in a single manufacturing step.

[0062] In an alternative variant, a first flat flexible glass membrane 51 may be attached to the outer surface of the wind turbine blade housing 222, and a subsequent flat flexible glass membrane 51 may be bonded to the attached first flat flexible glass membrane 51. This process can then be repeated in later manufacturing steps for additional flat flexible glass membranes 51.

[0063] In one example, the flat flexible glass membrane 51 can be provided in multiple pieces. The length of the provided pieces can range from 200 mm to 3 meters or more. Specifically, the provided pieces can have a length of about 1 m. Thus, in different variations, a single flat flexible glass membrane 51 can be arranged to protect at least a portion of the leading edge 218, or multiple pieces can be arranged individually along the longitudinal direction of the wind turbine blade 22 to cover at least a portion of the leading edge 218.

[0064] In another example of this disclosure, arranging the protective element 41 may include attaching a preformed member to the outer surface of the wind turbine blade shell 222, covering at least a portion of the leading edge 218. The preformed member may include one or more flexible glass films 51, 61. Thus, instead of an initially flat flexible glass film 51, a member with a pre-existing curvature can be provided and attached to the wind turbine blade shell 222. More specifically, the protective member may be manufactured in such a way that a curvature substantially matches the curvature of the blade shell 222 in the region of the leading edge 218 of the wind turbine blade 22. This facilitates the attachment of the protective element to the blade shell 222 of the wind turbine blade 22.

[0065] Figure 6An example of a system and method for arranging a protective element 41 covering at least a portion of a leading edge 218 is shown, wherein the protective element 41 includes a preformed member. In this example, the preformed member includes a flexible preformed member comprising one or more preformed flexible glass films 61. In different variations of this example, the preformed glass film member may comprise a single preformed flexible glass film 61 or multiple preformed flexible glass films 61. In the latter case, the multiple preformed flexible glass films 61 may be pre-bonded, i.e., they may be bonded to each other in a manner similar to that explained for the reference flat flexible glass film 51 before being attached to the leading edge 218.

[0066] Using a pre-formed flexible glass membrane 61 reduces stress in the glass membrane during handling and bonding to the blade shell 222. More specifically, the pre-formed flexible glass membrane 61 can be pre-formed during its manufacturing process to facilitate subsequent operations. Thus, the pre-formed flexible glass membrane 61 can be pre-formed with a U-shaped bend. In any case, the pre-formed flexible glass membrane 61 can still retain its flexibility to adapt to and conform to the curvature of the leading edge 218. In other words, even though the pre-formed flexible glass membrane 61 may have a certain curvature, it can maintain its flexibility such that during attachment it conforms to the curvature of the leading edge 218 in a similar manner to that explained by the reference initially flat flexible glass membrane 51.

[0067] In one example, the preformed flexible glass membrane 61 can be provided in multiple pieces. The length of the provided pieces can range from 200 mm to 3 meters or more. Specifically, the provided pieces can have a length of about 1 m. Each piece can be preformed with a bend to fit a specific section along the length of the leading edge 218 of the blade 22. Thus, in different variations, a single piece of preformed flexible glass membrane 61 can be arranged to protect at least a portion of the leading edge 218, or multiple pieces can be individually arranged longitudinally along the wind turbine blade 22 to cover at least a portion of the leading edge 218.

[0068] Figure 7 The blade housing 222 is schematically shown, with a protective element 41 covering at least a portion of the leading edge 218. Therefore, in this example, the protective element 41 can be as shown in... Figure 5 The flat flexible glass film 51 shown or as in Figure 6 The preformed flexible glass membrane 61 shown. The protective element 41 can be attached to the blade shell 222 in the region of the leading edge 218 and can extend along the leading edge 218 for a certain length, as shown in... Figure 3 As schematically shown. Furthermore, the protective element 41 may extend only in a certain area of ​​the leading edge 218 region, such that a first longitudinal extension edge 421 and a second longitudinal extension edge 422 may be defined respectively on the suction side and the pressure side.

[0069] In cases where a flat flexible glass membrane 51 is included, attaching the flat flexible glass membrane 51 to the outer surface of the wind turbine blade housing 222 may include bonding the initially flat flexible glass membrane 51 with an adhesive 53, specifically including an adhesive in a liquid state, a pressure-sensitive adhesive, or a hot melt adhesive.

[0070] During the attachment process, the flat flexible glass membrane 51 can deform to fit the curvature of the blade shell 222 in the region of the leading edge 218. To ensure proper fixation, tools can be used to hold the flexible glass membrane 51 in place, i.e., in close contact with the adhesive 53 on the surface of the blade shell 222. This is especially true when using a liquid adhesive.

[0071] Similarly, if still Figure 7 As shown, attaching a preformed component may include attaching a flexible preformed component, such as a preformed flexible glass film 61, to an adhesive 53, specifically an adhesive 53 comprising an adhesive, a pressure-sensitive adhesive, or a hot melt adhesive in a liquid state.

[0072] In the examples disclosed herein, different types of adhesives may be used. Therefore, adhesives in a liquid state, such as two- or three-component adhesive materials, may be used. The adhesive may be applied to the outer surface of the blade housing 222 in the region of the leading edge 218, i.e., in the attachment region, and / or to the surface of the flexible glass films 51, 61 to be bonded to the blade housing 222, i.e., the surfaces of the flexible glass films 51, 61 facing the wind turbine blade 22 at the time of attachment. In other examples, pressure-sensitive adhesives (PSA) may be used. In this case, single or double-sided PSA may be used. In still some examples, adhesive tape (single or double-sided) or self-adhesive tape (also single or double-sided) may be used as adhesive 53.

[0073] In some examples, the surface of the blade shell 222, particularly in the region of the leading edge 218, may be coated and / or painted before the adhesive 53 is applied to attach the flexible glass membranes 51, 61. In other examples, such a coating and / or paint may not be present and the adhesive may be applied to the fiber-reinforced composite.

[0074] Furthermore, in the examples disclosed herein, when used in Figure 5-7In any of the examples shown, different additional materials may be provided between the laminate of the blade shell 222 and the flexible glass membranes 51, 61. While not limited to this, this is particularly true when the protective element 41 is arranged within a wind turbine blade 22 already in the field. Therefore, putty may be provided to rebuild eroded or damaged laminates of the blade shell 222 in the area of ​​the leading edge 218. As shown, this can be used when retrofitting or maintaining the wind turbine blade 22 in the field, and the putty can be used for structural or non-structural purposes. Furthermore, pore fillers may be used to obtain a smooth surface. Such pore fillers may be applied over previously arranged putty or directly onto the laminate of the blade shell 222. Liquid adhesives may also be used to rebuild the leading edge 218 of the blade shell 222.

[0075] Figures 8A-8C Another example of a system and method for manufacturing a protective element 41 for the leading edge 218 of a wind turbine 10 is schematically depicted. In this example, a preformed component is also provided by the method. In particular, in this case, the preformed component may include a prefabricated, relatively rigid component 71 having a curvature substantially matching the curvature of the wind turbine blade shell 222 in the region of the leading edge 218. The method may further include attaching the relatively rigid component 71 to the outer surface of the wind turbine blade shell 222, covering at least a portion of the leading edge 218. In this case, the prefabricated, relatively rigid component 71 can be understood as an erosion shield.

[0076] In this example, a flexible glass membrane can be incorporated into a relatively rigid component, which can act as a mechanical shield to protect the leading edge 218 of the wind turbine blade 22. A prefabricated, relatively rigid component 71 can be attached to the leading edge 218 of the wind turbine blade 22 during production. Alternatively, the relatively rigid component 71 can be attached to a wind turbine blade 22 already installed in the field.

[0077] As in Figure 8A As shown, the relatively rigid component 71 may include one or more flexible glass membranes 51, 61 and fiber stacks 101. Therefore, an initially flat flexible glass membrane 51 or a pre-formed flexible glass membrane 61 with a specific curvature may be used. A mold 81 may be used to manufacture the relatively rigid component 71 by placing the flexible glass membranes 51, 61 together with the fiber stacks 101 in the mold 81 and by co-infusing the flexible glass membranes 51, 61 and the fiber stacks 101 with resin. Regarding the fiber stacks 101, glass, carbon, or a mixture of glass and carbon fibers may be selected. Furthermore, resins with different chemical properties, such as polyester, epoxy, polyurethane, vinyl ester, thermoplastic resin, etc., may be used for the infusion process. After co-curing, the fiber stacks 101 and the flexible glass membranes 51, 61 may be solidified to form the relatively rigid component 71. In some examples, co-infusion and co-curing may include the use of a vacuum.

[0078] In other examples, the relatively rigid component 71 can be manufactured using pre-impregnated (prepreg) fibers, which can be arranged in a mold 81 and cured to form a fiber-reinforced composite, thus avoiding the need for a resin infusion process.

[0079] As in Figure 8A As shown, flexible glass membranes 51 and 61 can be first placed onto a molding surface defined by the cavity of mold 81, and fiber laminate 101 can then be arranged on top of the previously arranged flexible glass membranes 51 and 61. The molding surface of mold 81 can be configured to form the outer surface of a relatively rigid member 71, which is shaped in a manner substantially complementary to the surface of blade shell 222 in the region of leading edge 218. In this way, flexible glass membranes 51 and 61 can be held at one of the surfaces of the relatively rigid member 71 and more specifically at, as shown in Figure 8C The diagram shows a surface that can be configured to face the wind turbine blade 22 or the exterior. In a variant example, multiple flexible glass membranes 51, 61 can be arranged in a laminated configuration with a first flexible glass membrane 51, 61 forming the outer surface of a relatively rigid member 71. The flexible glass membranes 51, 61 can be bonded together and can be integrated with multiple fiber stacks 101.

[0080] The use of a relatively rigid component 71 provides increased mechanical stability and enhanced erosion protection. The mold 81 can be used in a shape that substantially matches the U-shaped bend of the leading edge 218 of the wind turbine blade 22 at the location where the relatively rigid component 71 is to be positioned. In other words, the inner surface of the relatively rigid component 71 can be substantially complementary to the attachment surface of the rotor blade shell 222. However, even though the relatively rigid component 71 can be substantially rigid and robust, it still retains a slight flexibility, allowing it to be adjusted to the precise geometry of the leading edge 218. In this way, tolerances in the manufacturing and assembly processes can be improved.

[0081] After the pre-formed and relatively rigid component 71 is manufactured, attachment to the blade shell 222 can be performed in the region of the leading edge 218 of the wind turbine blade 22. Specifically, attaching the relatively rigid component 71 may include, for example, bonding the relatively rigid component 71 with an adhesive 53 and / or securing the relatively rigid component 71 by mechanical interference using corresponding mechanical features in the relatively rigid component 71 and on the outer surface of the wind turbine blade shell 222. In examples including adhesive attachment, a liquid adhesive may be used. In examples including mechanical fixation, fastening devices may be provided in the region of the leading edge 218 of the wind turbine blade shell 222, which may be configured to engage with corresponding connection features in the relatively rigid component 71.

[0082] Another example of a method for manufacturing a wind turbine blade 22 with enhanced leading-edge protection may be provided for including a leading-edge laminate 228 (see...). Figure 3-4 The wind turbine blade 22 is structurally reinforced in the leading edge 218 of the wind turbine blade shell 222. Therefore, the leading edge laminate 228 can be formed by placing a fiber laminate over at least a portion of the area covering the leading edge 218. Arranging the protective element 41 may include providing at least one flexible glass membrane 51, 61 in combination with the fiber laminate and co-infusing the fiber laminate and the flexible glass membrane with resin to obtain a fiber-reinforced composite.

[0083] This method is particularly applicable during blade manufacturing. Therefore, it is common practice to provide a leading-edge laminate 228 to reinforce this region of the wind turbine blade 22. In some examples, the wind turbine blade 22 can be manufactured by creating two separate shells, namely a pressure-side shell and a suction-side shell, in a corresponding mold. These two shells are then bonded together at least along the trailing edge 220 and leading edge 218 of the wind turbine blade 22 to form the blade shell 222. After the two shells are bonded, a dedicated laminate can be provided in the region of the leading edge 218. In other examples, a single mold can be used to manufacture the complete blade shell 222 in a single step. In this case, the region corresponding to the leading edge 218 can also be reinforced with a dedicated laminate. To provide the leading-edge laminate 228, a plurality of fiber stacks or pads can be arranged on the wind turbine blade shell 222 along at least a portion of the region of the leading edge 218, either extending the entire length of the blade 22 or at selected longitudinal locations.

[0084] According to this example, one or more flexible glass membranes 51, 61 may be included concurrently with the leading edge laminate 228. Specifically, the flexible glass membranes 51, 61 may be added to the outer surface of the leading edge laminate 228 such that it faces the outside of the wind turbine blade 22 during operation. Advantageously, the flexible glass membranes 51, 61 may be co-infused with resin and co-cured with the fiber laminate for the leading edge laminate 228. This facilitates the manufacturing process by integrating the formation of the leading edge laminate 228 and the formation of the leading edge protection into a single manufacturing step. Furthermore, this method can also lead to enhanced mechanical integration of the leading edge protection system within the structure of the blade 22. In this example, the consolidation of the flexible glass membranes 51, 61 and the fiber laminate may or may not include the use of vacuum and / or pressure. Additionally, heat may be applied during the curing process of the material to improve the performance of the arrangement. Alternatively, curing at ambient temperature may also be used.

[0085] In some examples, the arrangement of the protective element 41 covering at least a portion of the leading edge 218 of the wind turbine blade 22 can be integrated with the manufacturing of the wind turbine blade shell 222, thus creating a so-called "in-mold" operation. In these examples, the method may include arranging one or more flexible glass membranes 51, 61 in a mold used to manufacture the wind turbine blade shell 222. Furthermore, a fiber laminate may be arranged in the mold used to manufacture the wind turbine blade shell 222. Subsequently, the fiber laminate and the flexible glass membrane may be infused with resin, and the resin may be cured to obtain a fiber-reinforced composite.

[0086] Such a co-infusion and co-curing process (which may or may not involve the application of vacuum) results in the placement of the protective element 41, i.e., the protective element 41 inserted into the blade housing 222. Therefore, improved mechanical and structural integration of the protective element 41 can be achieved, thereby improving lifespan performance and reducing the frequency of maintenance operations and / or the risk of detachment or dislodgement. As in the previous example, resins with different chemical properties, such as polyester, epoxy, polyurethane, etc., can be selected to directly integrate the flexible glass films 51, 61 onto the laminate or multiple laminates forming the wind turbine blade housing 222.

[0087] In examples including such an "in-mold" process, the flexible glass membranes 51 and 61 can be positioned to cover only portions of the mold surface corresponding to the area around the leading edge 218, and more specifically, to those sections around the leading edge 218 where the protective element 41 is intended to be placed. The flexible glass membranes 51 and 61 can be provided as a single piece or can be cut into multiple pieces. Specifically, the length of the provided pieces can range from 200 mm to 3 meters or more. More specifically, the provided pieces can have a length of about 1 m. Thus, in one variation of this disclosure, a single flexible glass membrane 51 or 61 can be placed in a corresponding portion of the mold surface. In other variations, multiple pieces can be individually arranged on the mold surface at selected locations corresponding to different positions along the length of the wind turbine blade 22.

[0088] Figure 9 An example of another aspect of this disclosure is provided. Thus, a method for arranging the protective element 41 can be provided, which may further include applying a sealant 55 at the edges of the protective element 41 to seal the joint between the protective element 41 and the wind turbine blade housing 222. Specifically, sealant 55 may be applied at all edges of the protective element 41 to seal all joints between the protective element 41 and the wind turbine blade housing 222. Applying such sealant 55 is consistent with the previously referenced... Figure 5-8 Any of the examples shown can be useful. Therefore, all examples including the attachment of the protective element 41 to the outer surface of the blade housing 222 can benefit from the use of such a sealant 55. In some examples, the sealant 55 may be provided as an adhesive material, which can be disposed at the corresponding edges, not only sealing the system but also further enhancing mechanical fixation.

[0089] Many other advantages can be associated with the use of sealant 55. On the one hand, sealant 55 helps prevent moisture intrusion and, more generally, the effects of environmental conditions. This improves the attachment of the protective element 41, thus reducing the risk of detachment and improving the operation and maintenance of the wind turbine 10. On the other hand, sealant 55 can be configured to achieve a smooth transition between the protective element 41 and the surface of the blade housing 222.

[0090] Figure 10 Another example is shown that allows for a smooth transition between the surfaces of the protective element 41 and the blade housing 222. In this example (which can also be referenced...), Figure 5-9 In any of the example combinations shown, the protective element 41 may be narrowed or chamfered in the chordal and / or length directions, thus allowing for extension along longitudinal edges 421, 422 and / or along side edges 411, 412 (see Figure 3 A smooth transition to the surface of the blade 22. A smooth transition can help improve the aerodynamic performance of the wind turbine blade 22. In addition, the chamfered transition can also avoid noise at the step between the protective element 41 and the surface of the blade shell 222.

[0091] The described example demonstrates a symmetrical arrangement of the protective element 41. In some alternative examples, the protective element 41 may be arranged asymmetrically relative to the leading edge 218, such that the extension of the protective element 41 extending from the leading edge 218 toward the suction side 226 may be larger than the extension of the protective element 41 extending from the leading edge 218 toward the pressure side 224. Therefore, even if a fairly smooth transition can be provided between the protective element 41 and the surface of the blade shell 222, the presence of even minor irregularities on the surface of the wind turbine blade 22 can cause some undesirable aerodynamic effects. Therefore, in order to better control the aerodynamic flow along the surface of the wind turbine blade 22, the precise design of the protective element 41 can provide efficient coverage of the relevant portion of the blade shell 222 in the region of the leading edge 218, while maintaining substantially unaffected aerodynamic performance.

[0092] like Figure 3As indicated in the present disclosure, one example may include a wind turbine blade 22, wherein the protective element 41 may comprise multiple portions distributed longitudinally along the wind turbine blade 22. Specifically, at least two of the multiple portions may have different characteristics, and more specifically, at least one portion arranged closer to the tip 215 of the wind turbine blade 22 may have a greater thickness than the other portions. Thus, by dividing the protective element 41 into multiple portions, optimized protection can be provided, achieving an optimal balance between leading-edge protection, weight, and cost. Specifically, some of the examples shown above may be combined in a single wind turbine blade 22 by using different solutions at different locations. Furthermore, different flexible glass films 51, 61 and / or different numbers of such flexible glass films 51, 61 may be provided at different locations. More specifically, thicker flexible glass films 51, 61 and / or a greater number of flexible glass films 51, 61 may be provided in the region of the wind turbine blade 22 where increased resistance to leading-edge erosion protection is required.

[0093] Furthermore, in the examples disclosed herein, the thickness of the protective element 41 may also be optimized based on environmental conditions (e.g., rainfall conditions) at the location where the wind turbine 10 is erected.

[0094] To better withstand environmental conditions and reduce maintenance costs during the service life of the wind turbine 10, flexible glass films 51 and 61 may be provided with ultraviolet (UV) protection to prevent degradation.

[0095] In addition to the wind turbine blade 22, a protective element 41 for the wind turbine blade 22 is also provided by this disclosure. The wind turbine blade 22 has a longitudinal length from the root end 217 to the tip end 215 and includes a wind turbine blade shell 222 having an aerodynamic profile with a pressure side 224 and a suction side 226 and defining a leading edge 218. The protective element 41 includes flexible glass membranes 51, 61 and is configured to cover at least a portion of the leading edge 218 of the wind turbine blade 22 and extend along at least a portion of the length of the wind turbine blade 22.

[0096] Several examples have been provided, including the use of flexible glass membranes 51 and 61 to protect the leading edge 218 of wind turbine blade 22. However, other uses are also intended for such flexible glass membranes 51 and 61. Therefore, flexible glass membranes 51 and 61 can be integrated into any laminate constituting the wind turbine blade 22, for example, as part of the wind turbine blade shell 222 or as part of the beam caps 274 and 276. In fact, the mechanical properties of the flexible glass membranes 51 and 61 are not oriented; that is, they are isotropic. This property can be used to complement or compensate for the orientation of commonly used fiber laminates (whose properties are determined by the orientation of the fibers).

[0097] Therefore, in one example of this disclosure, a wind turbine blade 22 is provided, wherein the wind turbine blade shell 222 includes a fiber-reinforced composite comprising a plurality of fiber stacks. During the manufacturing process, the fiber stacks may be infused with resin and subsequently cured. One or more flexible glass membranes 51, 61 may be placed together with the fiber stacks. Specifically, the flexible glass membranes 51, 61 may be placed below or above the fiber stacks. After resin infusion and curing (with or without vacuum consolidation), a composite component with optimized structural properties can be achieved.

[0098] The materials selected for the fiber laminates may depend on the components of the wind turbine blade 22. Therefore, glass fiber may be selected for the blade shell 222, while carbon fiber may be preferred for the beam caps 274, 276. In all cases, the laminate may comprise multiple fiber laminates or layers, for example, between five and fifty layers may be used. Depending on specific needs, one or more flexible glass membranes 51, 61 may be arranged with the layers. Furthermore, the flexible glass membranes 51, 61 may be arranged only at selected longitudinal locations on the wind turbine blade shell 222. Specifically, the flexible glass membranes 51, 61 may be arranged only at specific portions along the longitudinal direction of the wind turbine blade 22.

[0099] Figure 11 An example schematically illustrates the steps during the manufacture of a wind turbine blade shell 222, in which flexible glass membranes 51, 61 can be integrated into the wind turbine blade shell 222. In this example, a mold 91 may be provided. The mold 91 can be used to manufacture one of the blade shell halves, i.e., for the pressure side shell or the suction side shell. Figure 11 As shown, one or more flexible glass films 51, 61 can be placed on the inner surface of the mold 91. Subsequently, a fiber stack 104 can be disposed on top of the flexible glass films 51, 61. Therefore, the flexible glass films 51, 61 can be disposed together with the fiber stack 104.

[0100] Even though this example shows a single flexible glass membrane 51, 61 arranged together with the fiber stack 104, more flexible glass membranes 51, 61 can be provided. Furthermore, although in Figure 11 Not visible in the middle, different materials and combinations can be used at different locations along the length of mold 91. A resin infusion process can be performed after different layers are provided, as is well known to those skilled in the art. Subsequently, a curing step can be performed to obtain a fiber-reinforced composite to complete the blade shell. In another example (not shown in...) Figure 11 As shown in the figure, additional flexible glass films 51 and 61 can be arranged on the fiber stack 104, so that the flexible glass films 51 and 61 can be disposed on and below the fiber stack 104.

[0101] Figure 11An example is shown in which mold 91 is provided for the blade shell half. However, in other examples of this disclosure, molds intended for manufacturing the complete blade shell in a single step may also be used.

[0102] In yet another example, several flexible glass films 51, 61 may be stacked to form at least a portion of the structural beam caps 274, 276 of the wind turbine blade 22.

[0103] This written description uses examples to disclose the teachings, including preferred examples, and also enables any person skilled in the art to practice the teachings, including making and using any apparatus or system and performing any of the included methods. The patentable scope is defined by the claims and may include other examples that would occur to a person skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not substantially differ from the literal language of the claims. Additional embodiments and techniques can be constructed by a person skilled in the art by mixing and matching aspects from the various embodiments described, as well as other known equivalents for each such aspect, in accordance with the principles of this application. If reference numerals related to the drawings are placed in parentheses in the claims, they are used only to enhance the comprehensibility of the claims and should not be construed as limiting the scope of the claims.

Claims

1. A method for manufacturing a wind turbine blade (22), the wind turbine blade (22) having a length in a longitudinal direction from a root end (217) to a tip end (215) and including a wind turbine blade shell (222), the wind turbine blade shell (222) having an aerodynamic profile with a pressure side (224) and a suction side (226), wherein, One or more flexible glass membranes (51, 61) are arranged in the wind turbine blade (22).

2. The method according to claim 1, wherein, The wind turbine blade shell (222) defines a leading edge (218), and the method includes arranging a protective element (41) covering at least a portion of the leading edge (218), the protective element (41) including at least one of the flexible glass films (51, 61) and extending along at least a portion of the length of the wind turbine blade (22).

3. The method according to claim 2, wherein, Arranging the protective element (41) includes attaching a flat flexible glass film (51) to the outer surface of the wind turbine blade shell (222), covering at least a portion of the leading edge (218), such that the flexible glass film (51) conforms to the shape of the wind turbine blade shell (222) in the leading edge (218). Specifically, attaching the flexible glass film (51) to the outer surface of the wind turbine blade shell (222) includes bonding the flexible glass film (51) with an adhesive (53), more specifically including an adhesive (53) in a liquid state, a pressure-sensitive adhesive, or a hot melt adhesive.

4. The method according to claim 2 or 3, wherein, Arranging the protective element (41) includes attaching a preformed component to the outer surface of the wind turbine blade shell (222) to cover at least a portion of the leading edge (218), the preformed component comprising one or more of the flexible glass films (51, 61).

5. The method according to claim 4, wherein, The preformed component includes a flexible preformed component comprising one or more preformed flexible glass films (61), and further wherein attaching the preformed component comprises attaching the flexible preformed component using an adhesive (53), specifically using an adhesive (53) comprising an adhesive in a liquid state, a pressure-sensitive adhesive, or a hot melt adhesive.

6. The method according to claim 4 or 5, wherein, The preformed component includes a pre-fabricated relatively rigid component (71) having a curvature substantially matching the curvature of the wind turbine blade shell (222) in the leading edge (218), and further wherein attaching the preformed component includes attaching the relatively rigid component (71) to the outer surface of the wind turbine blade shell (222), covering at least a portion of the leading edge (218).

7. The method according to claim 6, wherein, The relatively rigid component (71) comprises one or more flexible glass films (51, 61) and fiber stacks (101), and further wherein the relatively rigid component (71) is manufactured using a mold (81) by placing the flexible glass films (51, 61) together with the fiber stacks (101) in the mold (81) and by co-infusing the flexible glass films (51, 61) and the fiber stacks (101) with resin.

8. The method according to any one of claims 2 to 7, wherein, The wind turbine blade (22) includes a leading edge laminate (228) to structurally reinforce the wind turbine blade shell (222) at the leading edge (218), the leading edge laminate (228) being formed by placing a fiber stack over a region covering at least a portion of the leading edge (218), and further wherein arranging the protective element (41) includes combining with the fiber stack to provide at least one flexible glass membrane (51, 61) and co-infusing the fiber stack and the flexible glass membrane (51, 61) with resin.

9. The method according to any one of claims 2 to 8, wherein, Arranging the protective element (41) includes: One or more flexible glass films (51, 61) are arranged in the mold used for manufacturing the wind turbine blade shell (222). Fiber laminates are arranged in a mold used for manufacturing the wind turbine blade shell (222). The fiber laminate and the flexible glass membrane (51, 61) are infused with resin, and The resin is cured.

10. The method according to any one of the preceding claims, wherein, The wind turbine blade shell (222) includes multiple fiber stacks and at least one of the flexible glass films (51, 61) is positioned below or above the fiber stacks.

11. The method according to claim 10, wherein, The flexible glass membrane (51, 61) is arranged only at selected longitudinal positions on the wind turbine blade shell (222), and specifically, the flexible glass membrane (51, 61) is arranged only at specific portions along the longitudinal direction of the wind turbine blade (22).

12. A wind turbine blade (22) having a length in the longitudinal direction from a root end (217) to a tip end (215) and comprising a wind turbine blade shell (222) having an aerodynamic profile with a pressure side (224) and a suction side (226), wherein, The wind turbine blade (22) includes one or more flexible glass membranes (51, 61).

13. The wind turbine blade (22) according to claim 12, wherein, The wind turbine blade shell (222) defines a leading edge (218), and the wind turbine blade (22) further includes a protective element (41) comprising at least one of the flexible glass films (51, 61), and further wherein the protective element (41) is configured to cover at least a portion of the leading edge (218) and to extend along at least a portion of the length of the wind turbine blade (22), specifically for extending at least one-third of the length of the wind turbine blade (22).

14. The wind turbine blade (22) according to claim 13, wherein, The protective element (41) includes a plurality of portions distributed along the longitudinal direction of the wind turbine blade (22), wherein at least two of the plurality of portions have different characteristics, and more specifically, wherein at least one portion arranged closer to the tip (215) of the wind turbine blade (22) has a greater thickness than the other portions.

15. The wind turbine blade (22) according to any one of claims 12 to 14, wherein, The blade shell (222) includes a fiber stack, and at least one of the flexible glass films (51, 61) is arranged together with the fiber stack.

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