Wind turbine anti-icing protection

Abstract

A pitch-controlled wind turbine includes a tower, a nacelle mounted on the tower, a hub rotatably mounted on the nacelle, and at least three blades. The wind turbine includes at least three blade connection members, each extending between adjacent wind turbine blades. The wind turbine has at least three pretensioning members, each connected to one of the blade connection members and connected to the hub via a tensioning device. The tensioning device is configured to provide pretension in the blade connection member to which it is connected. An anti-icing system and / or a de-icing system is provided, including one or more heating elements for protecting one or more blades. One or more power supply paths for the anti-icing system or de-icing system are arranged between the hub and the heating elements along at least one of the blade connection members and pretensioning members.

Description

Technical Field

[0001] This invention relates to a pitch-controlled wind turbine with an anti-icing system and / or a de-icing system. Background Technology

[0002] Wind turbines are typically deployed in areas with low temperatures and severe weather conditions, which causes ice to form on the turbine blades.

[0003] The accumulation of ice on wind turbine blades presents several significant challenges. First, it increases the overall weight of the blades, potentially leading to imbalances and mechanical stress on critical components. Furthermore, icing on the blades impairs aerodynamic performance, which can result in reduced efficiency and costly maintenance. Additionally, ice ejection from the blades can cause structural damage, impacting the wind turbine's lifespan. This is particularly problematic in pitch-controlled wind turbines with blade load-sharing connection members, which include various additional components designed to support larger blades. These additional components can be susceptible to damage from increased mechanical stress and the impact of ice ejection.

[0004] Therefore, anti-icing systems designed to prevent icing and / or de-icing systems for removing accumulated ice are important for ensuring the reliable and continuous operation of wind turbines in cold climates. Summary of the Invention

[0005] A first aspect of the invention provides a pitch-controlled wind turbine, comprising a tower, a nacelle mounted on the tower, a hub rotatably mounted on the nacelle, and at least three wind turbine blades, wherein each wind turbine blade extends between a tip and a root end connected to the hub via a pitch mechanism; the wind turbine further comprises at least three blade connection members, each blade connection member extending from a connection point on one wind turbine blade toward a connection point on an adjacent wind turbine blade, wherein the connection point on a given wind turbine blade is arranged at a distance from the root end and a distance from the tip end of the wind turbine blade; to The system includes at least three pretensioning members, each connected to one of the blade connecting members and connected to the hub via a tensioning device, the tensioning device providing radial movement of the radially inner end of the pretensioning member relative to the axis of rotation of the hub due to the extension or retraction of the tensioning device, thereby providing pretension in the blade connecting member to which each pretensioning member is connected; and an anti-icing system and / or a de-icing system, comprising one or more heating elements for protecting one or more wind turbine blades, wherein one or more power supply paths for the anti-icing system or the de-icing system are arranged between the hub and the heating elements along at least one of the blade connecting members and the pretensioning members.

[0006] Providing anti-icing and / or de-icing systems can protect the blades of pitch-controlled wind turbines with blade load-sharing connection members from ice buildup. It should be understood that the term "ice" as used herein refers to frozen water, including, for example, ice, snow, sleet, hail, slush, etc.

[0007] Reducing or preventing ice buildup on blades helps avoid problems caused by ice buildup, such as increased mechanical stress on turbines, increased load on mechanical components and reduced blade aerodynamic efficiency, reduced power generation efficiency, potential damage from ice ejection, and increased downtime and maintenance.

[0008] Electric heating elements provide precise and controlled temperature rise to melt ice or prevent icing. They generate heat quickly and efficiently, rapidly melting ice and restoring the function of wind turbine components. Furthermore, the use of electric heating elements eliminates the need for manual or mechanical de-icing or ice prevention, which would be extremely complex given the typical size and location of wind turbines.

[0009] Blade connection components enable wind turbine blades to support each other. The significance of this is that the load on the wind turbine blades, especially the load in the edge direction and to some extent the load in the flapping direction, is "shared" between the wind turbine blades.

[0010] The connection point on the wind turbine blade can be arranged at a distance from the root end between 10% and 60% of the length of the wind turbine blade from the root end to the tip end, preferably at 50% of the radial inner side of the corresponding wind turbine blade length from the root end, and more preferably at 45% of the radial inner side of the corresponding wind turbine blade length from the root end.

[0011] Connection points on wind turbine blades can be located at positions where the thickness-chord ratio of the wind turbine blade is between 20% and 50%.

[0012] Each wind turbine blade may include an inner portion containing the root end and an outer portion containing the tip end. The inner and outer portions may be connected to each other at a separated position. The inner portion may be connected to the outer portion via a connector. The connector may include a connector. The connector may be at least partially covered by a fairing.

[0013] Connectors can be metal components, preferably cast or machined. Connectors can be composite components. Connectors can be co-cured or co-bonded components. Providing such connectors improves the ease of manufacturing and provides lightweight, high-strength connectors.

[0014] A connector can be coupled to transfer load between the spar cap portion of the inner section of the blade and the spar cap portion of the outer section of the blade. The connector can be arranged to transfer the load from the blade connecting member to the spar cap portion of the inner section of the blade. This can improve the load transfer efficiency of the turbine blade because the spar cap portion can be designed to withstand higher loads than the blade casing.

[0015] Each tensioning device may include an actuator having a first portion coupled to the hub and a second portion movable relative to the first portion and coupled to a corresponding pretensioning member.

[0016] Each wind turbine blade can be coupled to two blade connection members. Each of these two blade connection members can extend from a corresponding connection point of a blade.

[0017] Providing power source paths for anti-icing and / or de-icing systems along the blade connecting members and pretensioning members avoids the need for at least some power source paths to be routed inside the blade. Route power source paths inside the blade makes them difficult to maintain and access, and increases the need for or complexity of blade lightning protection. Furthermore, the blade's moment of mass can be higher because the power cables need to extend to the blade root. In contrast, providing such power source paths along the blade connecting members and pretensioning members provides easier access to the power source paths, allows for simpler maintenance, and reduces any downtime of the wind turbine should a problem occur. Lightning protection requirements for the blade can also be reduced, saving on blade manufacturing and operating costs and time.

[0018] In some arrangements, such as the power source routing described, radio frequency emissions from the interface connections between the blades and the nacelle can be reduced or eliminated.

[0019] In some configurations, lightning current transfer units (LCTUs) can be provided to transfer lightning current from the blade to the nacelle (i.e., to the ground via the tower) in the event of a lightning strike. Typically, the first LCTU is located between the blade and the hub, and the second LCTU is located between the hub and the nacelle.

[0020] The first LCTU is typically located at the blade root or on the outer surface facing the blade root. Therefore, the first LCTU is exposed to the environment, making it susceptible to wear and corrosion. The power source path layout described herein helps to direct lightning current from the blade to the hub via power source paths on the blade connection members and / or pre-tensioning members. In this way, the first LCTU can be bypassed or completely removed without adversely affecting the turbine's lightning protection.

[0021] The blade connection members and / or pretensioning members may include conductive materials. The conductive material may be a structural load-bearing conductive material. This structural load-bearing material can be used to support tensile loads in the blade connection members and / or pretensioning members. The conductive material may be, for example, steel or carbon (e.g., pultruded carbon). In addition to supporting structural loads, the conductive material can also be used to transmit power along the power source path between the hub and the heating element.

[0022] Advantageously, the blade connection components and / or pretensioning components provide multiple functions in supporting the blades and supplying power to the anti-icing and / or de-icing systems. This reduces the number of components required for the wind turbine, increases its simplicity, and facilitates easier maintenance.

[0023] The blade connection member and / or pretensioning member may include a structural load-bearing non-conductive material and a conductive material for transmitting power along the power source path between the hub and the heating element. The structural load-bearing non-conductive material may be used to support tensile loads in the blade connection member and / or pretensioning member. The non-conductive material may be, for example, ultra-high molecular weight polyethylene (UHMWPE).

[0024] Advantageously, the blade connection members and / or pretensioning members can provide the layout of the power source path between the heating elements in the hub and the blades without requiring their structural load-bearing materials to be made entirely of conductive materials. Non-conductive materials are generally lighter than conductive materials, thereby reducing the weight of the blade connection members and / or pretensioning members and thus reducing the mechanical load on the wind turbine, while conductive materials still facilitate the transfer of power to the blades via the blade connection members and / or pretensioning members.

[0025] Conductive materials can be embedded in the non-conductive materials of the corresponding blade connecting components or pre-tensioning components.

[0026] Embedding conductive materials within non-conductive materials protects the conductive materials from damage (e.g., from precipitation, debris, or dust), reducing the risk of damage to the conductive materials. The aerodynamic performance of blade connection components and / or pre-tensioning components incorporating conductive materials can be optimized. Furthermore, embedding conductive materials provides a convenient means of positioning and supporting the power source path relative to other components of the wind turbine, reducing the space and components required for anti-icing and / or de-icing systems. Specifically, the power source path can be provided without any additional support components. Instead, this function can be provided using pre-existing components (i.e., blade connection components or pre-tensioning components).

[0027] Conductive materials can be attached to the outer surface of the non-conductive material of the corresponding blade connecting component or pre-tensioning component.

[0028] Attaching conductive material in this manner provides a convenient means of positioning and supporting the power source path relative to other components of the wind turbine, reducing the space and components required for anti-icing and / or de-icing systems. Furthermore, by simply separating the conductive material from the outer surface of the non-conductive material, the conductive material can be easily accessed, removed, or replaced.

[0029] The conductive material is coupled to the corresponding blade connecting member or pretensioning member inside or outside the contour of the non-conductive material of the corresponding blade connecting member or pretensioning member.

[0030] It should be understood that the term "profile" refers to the profile defined by the core structural load-bearing element of the corresponding blade connection member or pretensioner member. In this way, the corresponding blade connection member or pretensioner member may have a recessed area defining a channel or hole, within which conductive material can be coupled (i.e., coupled within the profile). Alternatively, conductive material may be coupled to the outer surface (i.e., the outer profile) of the corresponding blade connection member or pretensioner member.

[0031] Coupled conductive materials in this way, a safe and convenient means of providing a power source path to wind turbine blades is provided, supported by the profile of the corresponding blade connection member or pretensioning member.

[0032] The blade connection members and / or pretensioning members with conductive material may further include a lightning protection system configured to isolate the conductive material from lightning strike attachment and to conduct lightning current.

[0033] A lightning protection system may include a conductive sheath or braided shield that is wound around at least a portion of the corresponding blade connection member or pre-tensioned member.

[0034] Advantageously, because the lightning protection system isolates the conductive materials from the lightning current, the risk of damage to the conductive materials due to lightning strikes is reduced. In this way, the maintenance requirements of the wind turbine are reduced.

[0035] Lightning protection systems may include metal mesh or metal layers. The metal mesh or metal layers may be arranged circumferentially around the conductive material of the blade connection members and / or pretensioning members.

[0036] When power is transmitted along the power source path between the hub and the heating element, the power source path can provide residual or inherent heat to protect the blade connecting members or pretensioning members from icing or to achieve de-icing (during operation of the heating elements in the blade, when power is supplied along the power source path). The secondary effect of resistance heating generated by transmitting power along the blade connecting members and pretensioning members to power the blade heating elements eliminates the need for separate dedicated electric heating elements to provide anti-icing or de-icing for the blade connecting members and pretensioning members.

[0037] Advantageously, the power source path can be used to prevent or remove icing from blade connection members and / or pretensioning members. In pitch-controlled wind turbines with load-sharing blade connection members, protecting the blade connection members or pretensioning members from icing is crucial. This inherent or residual heat reduces icing on the blade connection members or pretensioning members and / or improves de-icing without requiring any additional components, thus reducing the complexity of the wind turbine.

[0038] The anti-icing and / or de-icing system may include a power distribution system for distributing power to each wind turbine blade. The power distribution system may include a power distributor housed within the hub.

[0039] Placing the power distributor in the hub facilitates power distribution to each blade, eliminating the need for a separate power distributor on each blade. This reduces blade mass, thereby reducing rotor load, and makes maintenance or repair more accessible. Furthermore, it reduces the number of power distributors from three (one per blade) to one, simplifying blade design and manufacturing.

[0040] The anti-icing system and / or de-icing system may include one or more sensors in or above one or more blade connecting members or pretensioning members for detecting icing or conditions that are about to occur.

[0041] Installing sensors on the blade connecting members or pretensioning members can eliminate the need for sensors on the blades themselves to detect conditions related to blade icing. This can have significant advantages in reducing rotor mass, improving sensor accessibility for maintenance or repair, and reducing the need for blade lightning protection.

[0042] One or more sensors may be arranged in / on the hub, nacelle and / or blades to detect icing or conditions that may occur.

[0043] Anti-icing and / or de-icing systems may include one or more weather sensors (e.g., on the outside of a wind turbine) that can detect the condition of the turbine.

[0044] Providing sensors can improve control of anti-icing and / or de-icing systems and provide operators with up-to-date information on the condition of blade connection members or pre-tensioning members. The energy requirements of anti-icing and / or de-icing systems can be reduced because the systems operate only when needed (e.g., heating elements on the blades can be powered only when a predetermined amount of ice has accumulated, or when weather conditions indicate that ice will begin to accumulate), rather than operating continuously.

[0045] The sensor can be one or more of the following: accelerometer, temperature sensor, position sensor, load sensor, or strain sensor.

[0046] The sensor can be one or more of the following: liquid water content sensor, ice detection sensor, air pressure sensor, surface resistance or impedance sensor.

[0047] The one or more sensors may be provided at multiple locations along the length of the blade connecting member or pretensioning member.

[0048] The one or more sensors may be provided along substantially the entire length of the blade connecting member or pretensioning member.

[0049] Advantageously, the sensors can acquire the necessary data at multiple locations or along the entire length of the corresponding blade connecting member or pre-tensioning member, providing the operator with information about the member's status in various positions. In this way, the possibility of obtaining erroneous data is reduced, further preventing the anti-icing and / or de-icing systems from operating when not needed.

[0050] Providing multiple sensors improves the redundancy of the sensor arrangement because if one sensor fails, the others can still provide indications about the condition of the blade connection or pretensioning member. Multiple sensors also enable measurements, such as measuring the resonant frequency of the blade connection or pretensioning member; changes in the resonant frequency can indicate the degree of icing on the blade connection or pretensioning member.

[0051] The anti-icing or de-icing system may include a lightning protection system, which includes a lightning discharge filter system, preferably housed within the wheel hub. The lightning discharge filter system may, for example, include an inductor, an isolation transformer, and / or surge protection devices.

[0052] Placing the lightning discharge filter system in the hub rather than the blade provides easier access for maintenance, as the hub is more accessible than each blade. By removing the power supply lines for the blade heating elements from inside the blade and routing them via blade connecting members or pre-tensioning members, the need for lightning protection of the internal blade power supply lines can be eliminated.

[0053] The wind turbine may also include at least three pretensioning members, each pretensioning member being connected between a blade connection member and a hub, and each pretensioning member being arranged to provide pretension in the blade connection member to which it is connected.

[0054] Pretensioning members can be connected to common points or public areas located at or near the wheel hub.

[0055] The hub may include a hub member extending substantially along a direction defined by the hub's axis of rotation. A pretensioning member may be attached to the hub member.

[0056] The blade connection member and / or pretensioning member may include at least one bearing. The at least one bearing may be located at or towards the end of the respective blade connection member and / or pretensioning member. The bearing may be non-conductive. The power supply path may be decoupled from the respective blade connection member and / or pretensioning member to bypass the at least one bearing.

[0057] Each wind turbine blade may include a leading edge, a leading edge extension, and a blade shell, wherein the leading edge extension extends forward of the leading edge, and the connection point of the corresponding wind turbine blade is located forward of the leading edge on the leading edge extension, and each wind turbine blade may also include a corresponding fairing extending at least on the leading edge extension. The power supply path may be decoupled from the corresponding blade connection member within the fairing.

[0058] Advantageously, the power source path does not extend across the bearing, avoiding any power transmission across the bearing. Decoupling the power source path from the blade connection components within the fairing provides additional protection for the decoupled power source path (i.e., the fairing provides coverage and protection from environmental influences), reducing the risk of power source path damage and failure.

[0059] Wind turbines can be upwind wind turbines. Attached Figure Description

[0060] Embodiments of the present invention will now be described with reference to the accompanying drawings, in which: Figure 1 A front view of a wind turbine based on the first example is shown; Figure 2 A side view of a wind turbine is shown; Figure 3 The image shows a wind turbine blade; Figure 4 A portion of a wind turbine according to the second example is shown; Figure 5A An exploded view of the connection joint is shown; Figure 5B A detailed view of the connector used to connect the blade section is shown; Figure 5C The image shows a wind turbine blade with a fairing. Figure 6 A schematic diagram of a wind turbine according to the third example is shown; Figure 7 A cross-sectional view of an example blade connection member or pretensioning member is shown; Figure 8 A schematic diagram of an example blade connection member or pretensioning member with a sensor arrangement is shown; Figure 9 A schematic diagram of an example blade connection member or pretensioning member with an alternative sensor arrangement is shown; Figure 10 A schematic diagram of a wind turbine according to the fourth example is shown; Figure 11 A cross-sectional view of an example blade connection member or pretensioning member is shown; Figure 12 A schematic diagram of a wind turbine according to the fifth example is shown; Figure 13 A cross-sectional view of an example blade connection member or pretensioning member is shown; Figure 14 A cross-sectional view of an example blade connection member or pretensioning member is shown; Figure 15 A flowchart of the power distribution system in a wind turbine according to the sixth example is shown. Detailed Implementation

[0061] In this specification, terms such as leading edge, trailing edge, pressure surface, suction surface, thickness, and chord length are used. Although these terms are well known and readily understood by those skilled in the art, definitions are provided below to avoid ambiguity.

[0062] The term leading edge is used to refer to the blade edge that will be located at the front of the blade when the blade rotates in the normal direction of rotation of the wind turbine rotor.

[0063] The term trailing edge is used to refer to the edge of a wind turbine blade that is located at the rear of the blade when the blade rotates in the normal direction of rotation of the wind turbine rotor.

[0064] The chord length of a blade is the straight-line distance from the leading edge to the trailing edge in a given cross section perpendicular to the blade's span. The term chord direction is used to refer to the direction from the leading edge to the trailing edge or vice versa.

[0065] The pressure surface (or windward surface) of a wind turbine blade is the surface between the leading and trailing edges. When the blade is in use, the pressure on the pressure surface is higher than that on the suction surface of the blade.

[0066] The suction side (or leeward side) of a wind turbine blade is the surface between the leading and trailing edges. When the blade is in use, the pressure acting on the suction side will be lower than the pressure on the pressure side.

[0067] The thickness of a wind turbine blade is measured perpendicular to the blade chord length and is the maximum distance between the pressure and suction surfaces in a given cross section perpendicular to the blade span direction.

[0068] The term spanwise refers to the direction from the root tip to the tip tip of a wind turbine blade, or vice versa. When wind turbine blades are mounted on a wind turbine hub, the spanwise and radial directions will be essentially the same.

[0069] The term "outer side" refers to the radial direction from the blade hub towards the blade tip. The term "inner side" refers to the radial direction from the blade tip towards the hub.

[0070] A view perpendicular to both the spanwise and chordwise directions is called a planar shape view. This view is taken along the thickness dimension of the blade.

[0071] The term web or shear web is used to refer to the longitudinally, generally spanwise, reinforcing member of a blade that can transfer the load from one side of the windward and leeward sides of the blade to the other side.

[0072] Figure 1 and Figure 2 A pitch-controlled wind turbine 1 according to a first example is shown. Figure 1 This is the front view of wind turbine 1, and Figure 2 This is a side view of a wind turbine 1. The wind turbine 1 includes a tower 2 and a nacelle 3 mounted on the tower 2. A hub 4 is rotatably mounted on the nacelle 3 and carries three wind turbine blades 5 projecting outward from the nacelle 3. Although Figure 1 and Figure 2 The example wind turbine 1 shown has three blades 5, but it should be understood that other numbers of blades 5 are also possible.

[0073] When wind blows towards the wind turbine 1, the wind turbine blades 5 generate lift, which causes the generator (not shown) inside the nacelle 3 to generate electricity.

[0074] It should be understood that the wind turbine 1 depicted can be any suitable type of wind turbine 1. The wind turbine 1 shown is an upwind wind turbine, but it should be understood that the wind turbine 1 can be a downwind wind turbine. The wind turbine 1 can be an onshore wind turbine, such that the foundation is embedded in the ground, or the wind turbine 1 can be offshore installed, in which case the foundation will be provided by a suitable offshore platform.

[0075] Three blade connection members 6 interconnect adjacent wind turbine blades 5 between connection points 7a, 7b on the wind turbine blades. The connection members 6 are cables, such as metal (e.g., steel) or polymer (e.g., including ultra-high molecular weight polyethylene - UHMWPE) cables. In some examples, each wind turbine blade 5 is coupled to two blade connection members 6. Each pair of blade connection members 6 extends from a corresponding connection point 7a, 7b on one of the blades 5. Each blade connection member 6 can move independently at its corresponding first and second connection points 7a, 7b to which it is attached. Connection points 7a, 7b may include bearing structures (see...). Figure 5B ).

[0076] The pretensioning member 8 extends between each of the blade connecting members 6 and between common points or common areas (not shown) at or near the hub 4. Figure 1 and Figure 2 In the example shown, three pretensioning members 8 are provided, but it should be understood that more pretensioning members may be provided. The pretensioning members 8 extend to the hub 4. The pretensioning members 8 are configured to provide pretensioning in the blade connection member 6. The pretensioning members 8 are typically cables, such as metal or polymer cables.

[0077] The pretensioning member 8 is coupled or connected to the hub 4 via a corresponding tensioning device 9. Each tensioning device 9 provides radial movement of the radially inner end of the pretensioning member 8 relative to the axis of rotation of the hub due to the extension or retraction of the tensioning device 9. Each pretensioning member 8 thereby provides pretension in the blade connecting member 6 to which it is connected.

[0078] Although not shown, the tensioning device 9 may include an actuator having a first portion coupled to the hub 4 and a second portion movable relative to the first portion and coupled to a corresponding pre-tensioning member 8. The tensioning device 9 extends and retracts by the movement of the second portion relative to the first portion. The extension and retraction of the tensioning device 9 changes the tension in the pre-tensioning member 8. The actuator may be a linear actuator, a rotary actuator, etc.

[0079] The wind turbine blade 5 has a root end 11 near the hub 4, which is adapted to be connected to the hub 4, for example, via a pitch mechanism. The wind turbine blade 5 has a tip end 12 away from the hub 4. The blade 5 includes a leading edge 13 and a trailing edge 14 extending between the respective root end 11 and tip end 12. The blade 5 includes a suction side 15 and a pressure side 16 (see...). Figure 3 The thickness of blade 5 extends between the suction side 15 and the pressure side 16.

[0080] Connection points 7a and 7b are located between the root end 11 and the tip end 12 of the respective blade 5 (i.e., at a distance from the root end 11 and at a distance from the tip end 12). Connection points 7a and 7b can be located between 10% and 60% of the radial length of the wind turbine blade 5 from the root end 11 to the tip end 12, but preferably radially inward at 50% of the radial length of the wind turbine blade 5 from the root end 11 to the tip end 12, more preferably radially inward at 45% of the radial length of the wind turbine blade 5 from the root end 11 to the tip end 12, for example, approximately 30-40%. It should be understood that connection points 7a and 7b can be adjacent to each other. Alternatively, connection points 7a and 7b can be spaced apart from each other.

[0081] The wind turbine 1 includes an anti-icing system and / or a de-icing system 17. For clarity, the anti-icing system and / or de-icing system 17 is not described in detail. Figure 1 and Figure 2 As shown in the diagram. An anti-icing system and / or de-icing system 17 is configured to protect one or more wind turbine blades 5. The anti-icing system can be configured to prevent or reduce ice accumulation on a given wind turbine blade 5. The de-icing system can be configured to remove ice accumulated on a given wind turbine blade 5. Preventing or reducing ice accumulation on the wind turbine blade 5 avoids an increase in mechanical stress acting on the wind turbine 1 and prevents a decrease in power generation efficiency. It should be understood that the term "ice" as used herein refers to frozen water, including, for example, ice, snow, sleet, hail, slush, etc.

[0082] Figure 3 An example wind turbine blade 5 is shown. The thickness dimension of the blade 5 extends between the suction side 15 and the pressure side 16. Each blade 5 may have a cross-section with a substantially circular profile near the root tip 11. The blade 5 may transition from a circular profile to an airfoil profile as it moves outward from the root tip 11. The blade 5 may include a "shoulder" 22 outside the root tip 11, which is the widest portion of the blade with the maximum chord length. The blade 5 may have an airfoil profile with a gradually decreasing thickness in the outer portion of the blade. The gradually decreasing thickness may extend from the shoulder 22 to the tip 12.

[0083] Each blade 5 can be a split blade formed by an inner blade portion 23 and an outer blade portion 24 coupled together. Each blade portion 23, 24 has a blade shell 53, which defines corresponding leading edges 42a, 42b, trailing edges 43a, 43b, suction sides 44a, 44b, and pressure sides 46a, 46b.

[0084] The inner portion 23 and the outer portion 24 of each blade 5 can be connected at a joint indicated by the connecting line 40. The connecting line 40 between the inner and outer blade portions 23 and 24 can be spanwise separated and tangential. The inner portion 23 of the blade extends from the blade root 11 to the connecting line 40. The outer portion 24 of the blade extends from the blade connecting line 40 to the blade tip 12.

[0085] The connection joint can include any form of connection, such as a bolted connection. The connection joint can be at least partially covered by the fairing 20 (see Figure 5). For split blades, the fairing 20 can span the gap between the two connected blade sections 23, 24.

[0086] It should be understood that the blade 5 may have any number of blade portions 23, 24, with corresponding connecting joints between them. Alternatively, the blade 5 may not be a split blade, but may extend continuously from the root end 11 to the tip end 12 without any connecting joints.

[0087] like Figure 3 As shown, the anti-icing system and / or de-icing system 17 includes one or more heating elements 18 for protecting the wind turbine blades 5. The heating elements 18 are electrically powered and may be, for example, wire heating elements (e.g., nickel-chromium wire), tubular heaters, infrared heating elements, etc. The heating elements 18 are configured to melt ice and / or prevent ice accumulation on the surface 10 of the wind turbine blades 5 (e.g., by heating the outer surface 10 of the blades 5 to a temperature that reduces or prevents ice formation and / or accumulation). The electrically powered heating elements 18 provide precise, efficient, and controlled temperature rise to melt ice, evaporate water, and / or prevent icing.

[0088] The heating element 18 may be embedded, attached, or otherwise fixed or coupled to the corresponding blade 5 (e.g., attached to the outer surface 10 of the blade 5 or at least partially embedded within the blade 5). It should be understood that any number of heating elements 18 may be provided at different locations along the length of the blade 5, or heating elements 18 may be provided spanning most of the length of the blade 5.

[0089] One or more power source paths (or power transmission paths) 28 are provided for the anti-icing system and / or de-icing system 17 (e.g., for supplying power to the blade heating element 18). In addition to "sharing" the load among the wind turbine blades 5, the connecting member 6 and / or pretensioning member 8 also help supply power to the anti-icing system and / or de-icing system 17. Specifically, the one or more power source paths 28 are arranged along at least one of the blade connecting member 6 and pretensioning member 8 between the hub 4 and the heating element 18.

[0090] The power source path 28 is arranged between the heating elements 18 on the hub 4 and the blades 5 via the pre-tensioning member 8 and the blade connecting member 5, for example... Figure 4 As shown. For example, power source path 28 can be routed from hub 4 to all pretensioning members 8 and all blade connecting members 6 (e.g., to supply power to the heating element 18 on each blade 5). It should be understood that power source path 28 can be routed along any number of blade connecting members 6 and / or pretensioning members 8.

[0091] The power supply path 28, laid along the blade connecting member 6 and the pretensioning member 8, avoids the need for the power cable to extend significantly inside the blade 5, where maintenance and access are difficult. The blade connecting member 6 and the pretensioning member 8 provide a more accessible and maintainable power supply path.

[0092] In some arrangements, a Lightning Current Transfer Unit (LCTU) may be provided to transfer lightning current from blade 5 to nacelle 3 (i.e., to the ground via tower 4) in the event of a lightning strike on blade 5. Typically, a first LCTU is disposed between blade 5 and hub 4, and a second LCTU is disposed between hub 4 and nacelle 3. The first LCTU may include, for example, a blade strip that can be mounted to the blade root, a lightning ring, blade component contact devices, and nacelle-side contact devices mounted to the nacelle and adapted to provide lightning current transfer from the lightning ring.

[0093] The first LCTU is typically located at the root tip 11 of blade 5 or on the outer surface facing the root tip 11. Therefore, the first LCTU is exposed to the environment, making the unit susceptible to wear and corrosion. The arrangement of the power source path 28 (i.e., along the blade connecting member 6 and the pretensioning member 8) as described facilitates the diversion of lightning current from blade 5 to hub 4 via the power source path 28 on the blade connecting member 6 and the pretensioning member 8. In this way, the first LCTU can be bypassed or completely removed without adversely affecting the lightning protection of turbine 1.

[0094] When power is transmitted along the power source path 28 between the hub 4 and the heating element 18, the power source path 28 may additionally provide residual or inherent heat. In this way, the power source path 28 can protect the blade connection member 6 or the pretensioning member 8 from icing or achieve de-icing (i.e., during the operation of the heating element 18). When power is transmitted through the power source path 28, the power source path 28 can generate heat through resistance heating, for example by selecting a material that provides low resistance for the power source path 28, or by increasing the current flowing through the wires, or by any suitable means. Of course, the power source path 28 may be dedicated to providing power to the blade heating element 18 and may not provide any additional heating or anti-icing protection to the blade connection member 6 or the pretensioning member 8.

[0095] Configuring the power source path to provide residual or inherent heat during power transmission can be used to protect the blade connection member 6 and / or pretension member 8 from icing, as well as to protect the blade 5 without requiring any additional components.

[0096] The heating element 18 can be positioned on the outer portion of the blade 5, where anti-icing protection may be most needed due to the potential for icing at higher speeds. Advantageously, the blade connecting member 6 can be positioned further inside the rotor than the heating element 18, thus providing a convenient route for the power supply path 28 to the heating element 18. Of course, the blade heating element 18 can be additionally or alternatively positioned further inside the blade connecting member 6, in which case the power supply path 28 may be less direct when routed via the blade connecting member 6, but the advantage of avoiding routed power supply path 28 inside the blade 5 remains. In the case that the blade 5 is a split blade with a connecting joint, the connecting joint can facilitate a simple means of transferring power from the power supply path 28 on the blade connecting member 6 to the heating element 18. An example of this arrangement is shown in Figure 5. Of course, it should be understood that on blades 5 without a connecting joint, the connection point for attaching the blade connecting member 6 to the blade 5 will still have a suitable rigid structure through which the power supply path 28 can be configured to route to the heating element 18.

[0097] Figures 5A-5C An example wind turbine blade 5 with a fairing 20 is shown.

[0098] The blade portions 23 and 24 are coupled via a connection joint including a connector 47. The connector 47 connects the first blade end face 48 of the inner blade portion 23 to the second blade end face 27 of the outer blade portion 24. The connector 47 is adapted to transmit a load between the inner blade portion 23 and the outer blade portion 24.

[0099] The leading edge extension 49 may extend in front of the leading edge 13 of the blade 5. The leading edge extension 49 may be integrally formed with the connector 47; however, it should be understood that, in alternative examples, the leading edge extension 49 may be a separate component from the connector 47. The leading edge extension 49 may include connection points 7a, 7b attached to the connecting member 6. The first and second connection points 7a, 7b may be arranged in front of the leading edge 13 and adjacent to the pressure side 16, such as... Figure 5A As shown, this provides additional clearance for the connecting member 6 as the wind turbine blade 5 rotates around the nacelle 3 with the hub 4. Specifically, sufficient clearance can be provided between the connecting member 6 and the blade 5 when the blade 5 pitches between approximately -5 degrees and approximately +95 degrees. The connection points on the wind turbine blade 5 can be located at positions where the thickness-chord ratio of the wind turbine blade 5 is between 20% and 50%.

[0100] Connection points 7a and 7b allow the connecting member 6 a certain degree of freedom of movement at its respective connection points. Figure 5B In the example shown, connection points 7a and 7b allow each blade connection member 6 to rotate about the corresponding connection points 7a and 7b in two orthogonal rotational degrees of freedom. This allows each connection member 6 to move independently of each other, thereby reducing the constraints on the wind turbine 1.

[0101] The two orthogonal rotational degrees of freedom can be provided by a bearing structure, for example, Figure 5B As shown. In this example, the first rotational degree of freedom is provided by the pin 51 of the bearing structure, around which the corresponding blade connecting member 6 can rotate, and the second rotational degree of freedom is provided by the spherical sliding bearing 52 between the pin 51 and the corresponding connecting member 6. However, it should be understood that other bearing structures may also be applicable.

[0102] The blade connecting member 6 and the pretensioning member 8 may include a bearing 50 at or toward each end. The bearing 50 may define the end of the respective blade connecting member 6 or pretensioning member 8. In some arrangements, only one bearing 50 may be provided at or toward the end of the respective blade connecting member 6 or pretensioning member 8. It should be understood that the term "end" refers to the longitudinal end of the blade connecting member 6 or pretensioning member 8.

[0103] exist Figure 5B In this configuration, bearing 50 is arranged to assist in attaching connecting member 6 to bearing structure; for example, bearing 50 includes a bore for receiving a corresponding pin 51. Although not shown, bearing 50 may be configured to connect blade connecting member 6 to a corresponding pretensioning member 8, and pretensioning member 8 to a corresponding tensioning device 9.

[0104] Bearing 50 can be non-conductive (i.e., not electrically conductive). For example, bearing 50 can be formed of a non-conductive material. Figure 5B As shown, the power supply path 28 on the blade connecting member 6 does not extend beyond the bearing 50. The power supply path 28 is decoupled (or separated) from the blade connecting member 6 before reaching the bearing 50. The power supply path 28 can be diverted around the bearing 50, for example, to the electric heating element 18 on the blade 5. It should be understood that the power supply path 28 can be decoupled from the blade connecting member 6 and the pretensioning member 8 before each terminal so as to divert around the bearing 50 at each respective end.

[0105] Figure 5CA fairing 20 extending at least over the leading edge extension 49 is shown. As previously described, the wind turbine blade 5 may be split and includes a first blade portion 23 and a second blade portion 24 coupled together, for example via a connector 47 as described above. For split blades, the fairing 20 may extend over the leading edge extension 49 and the connector 47.

[0106] The power supply path 28 can be disposed along the blade connecting member 6 and disposed to the heating element 18 via the shroud 20. The shroud 20 may include an opening 21 for receiving the blade connecting member 6. The power supply path 28 may also be disposed through the opening 21 and then further guided from the shroud 20 to the heating element 18.

[0107] The power source path 28 can be decoupled from the blade connection member 6 within the fairing 20 (i.e., so as to be diverted around the bearing 50 within the fairing 20 and thus guided to the heating element 18 on the blade 5).

[0108] The blade connecting member 6 and the pretensioning member 8 can be configured in various ways to accommodate the power source path 28. Reference will now be made to... Figures 6 to 14 Examples of this configuration are discussed. It should be understood that these figures may represent blade connecting member 6 and / or pretensioning member 8.

[0109] First refer to Figure 6 A schematic diagram of an example wind turbine 1 is shown. The wind turbine 1 can be substantially the same as previously described, therefore only the differences will be discussed in detail. In the schematic diagram, only one blade 5 is indicated, and only one blade connection member 6 and / or pretensioning member 8 is indicated. It should be understood that the same arrangement can be applied to any number of blades 5 and / or blade connection members 6 and / or pretensioning members 8 of the wind turbine 1.

[0110] The anti-icing system and / or de-icing system 17 includes a power distribution system 25 configured to distribute power to each wind turbine blade 5. The power distribution system 25 will refer to... Figure 15 This will be discussed in more detail. The power distribution system 25 includes a power distributor 26. The power distributor 26 may include power outlets, monitoring systems, security features, etc. Figure 6 In this configuration, the power distributor 26 is housed within the hub 4, but it should be understood that the power distributor 26 can be located in any suitable location. Positioning the power distributor within the hub 4 protects it from damage (e.g., from dust, debris, ice, etc.) and facilitates an efficient power path from the central location to each blade 5. Furthermore, the centralized power distributor 26 in the hub 4 eliminates the need for power distributors in the blades 5. This can potentially reduce blade mass, thereby reducing rotor load, improving the maintenance accessibility of the power distribution system 25, and reducing the need for or complexity of lightning protection for the blades 5.

[0111] Electricity can be transmitted from the power distributor 26 in the hub 4 to the corresponding blade 5 via a power source path 28 laid along the corresponding blade connecting member 6 and the pretensioning member 8. For example, the power source path 28 can extend from the power distributor 26 in the hub 4, along the pretensioning member 8, along the blade connecting member 6 and to the corresponding blade 5.

[0112] exist Figures 6 to 14 In this assembly, the blade connecting member 6 and / or the pretensioning member 8 includes a conductive material 29. The conductive material 29 can be any material suitable for transmitting electricity along the power source path 28 between the hub 4 and the heating element 18. The conductive material 29 can be any material or combination of materials capable of conducting electricity, such as copper, aluminum, steel, silver, gold, graphite, copper alloys, carbon fiber, carbon fiber reinforced composites, conductive polymers, tin, nickel, or combinations thereof. The conductive material 29 can provide the power source path 28 along the blade connecting member 6 and / or the pretensioning member 8.

[0113] exist Figure 6 In the example, conductive material 29 is a structural load-bearing conductive material. For example, the structural load-bearing conductive material can be metal. In this way, conductive material 29 can be used both to provide a power source path 28 between hub 4 and blade 5, and to provide the function of blade connection member 6 and / or pretensioning member 8 (i.e., supporting the load of adjacent blades 5). In this way, the number of components in wind turbine 1 is reduced because a single cable can provide at least a portion of the power source path 28 to heating element 18 and can provide load sharing between adjacent blades 5.

[0114] Figure 7 This is a cross-sectional view of the example blade connecting member 6 and / or pretensioning member 8, for example... Figure 6 The blade connecting member 6 and / or pretensioning member 8. In this example, the entire cable of the blade connecting member 6 and / or pretensioning member 8 is formed of conductive material 29. In this way, the entire blade connecting member 6 and / or pretensioning member 8 can provide a power source path 28. It should be understood that in some examples, other materials may also be present, such as a shell or sheath surrounding the conductive material 29, as corrosion protection, or as an isolator that divides the conductive material into multiple conductive paths, for example, for different electrical phases or electrical return paths.

[0115] Back Figure 6The blade connection member 6 and / or pretensioner member 8 may include a lightning protection system 30 configured to isolate the conductive material 29 from lightning current. The lightning protection system 30 may couple the blade connection member 6 and / or pretensioner member 8 to ground (e.g., via hub 4, through tower 2 and nacelle 3). The lightning protection system 30 may include a lightning arrester mounted to the blade connection member 6 and / or pretensioner member 8. The arrester may be electrically coupled to a lightning current path (e.g., via a conductive cable (not shown)) that directs the current to ground. In the illustrated example, the lightning arrester is a lightning antenna 31, but it could be a lightning rod, lightning array, etc. The lightning antenna 31 is arranged such that any incident lightning strike will adhere to the antenna 31, and the lightning current will flow to ground along the lightning current path. The lightning protection system 30 reduces the risk of damage to the blade connection member 6 and / or pretensioner member 8 from lightning strikes because the conductive material 29 is isolated from the lightning protection system 30. Therefore, the risk of damage to the blade connecting member 6 and / or the pretensioning member 8 is reduced, thereby reducing the risk of the power supply to the electric heating element 18 being cut off and reducing the risk of damage to the structural integrity of the blade connecting member 6 and / or the pretensioning member 8.

[0116] In some arrangements, the lightning protection system 30 includes a metal mesh or metal layer (not shown). The metal mesh or metal layer may be arranged circumferentially around the conductive material 29 of the blade connection member 6 and / or the pretensioning member 8.

[0117] exist Figure 6 In the figure, the lightning protection system 30 includes a lightning discharge filter system 32. The lightning discharge filter system 32 is configured to divert surges occurring during a lightning strike from critical components of the wind turbine 1, particularly from the blade connection members 6 and / or the pretensioning members 8. The lightning discharge filter system 32 includes a path to ground (e.g., a low-resistance path). It can be seen in the figure that the lightning discharge filter system 32 is housed within the hub 4, but it should be understood that the lightning discharge filter can be located in any suitable location. Housed in the hub 4, the lightning discharge filter system 32 is advantageous in protecting it from damage and failure. Furthermore, placing the lightning discharge filter system 32 in the hub 4 provides a centralized operating point for the system 32 within the wind turbine 1, facilitating easier access (e.g., for maintenance), and requiring only one lightning discharge filter system compared to arranging one in each blade.

[0118] The anti-icing system and / or de-icing system 17 may include one or more sensors 19. Sensors 19 may be disposed within or on one or more of the blade connection members 6 or pretensioning members 8. Sensors 19 may be disposed inside the respective blade connection member 6 or pretensioning member 8 (e.g., embedded in a cable) or on the outer surface 34 of the respective blade connection member 6 or pretensioning member 8. Sensors 19 are configured to detect icing or impending icing. Sensors 19 may provide information to an operator or control system (not shown) regarding the state of the respective blade connection member 6 or pretensioning member, which will provide information about the state of the blade surface 10. The anti-icing system and / or de-icing system 17 may be configured such that the electric heating element 18 operates only when the sensor 19 detects icing or impending icing. In this way, the energy demand of the anti-icing system and / or de-icing system 17 is reduced because one or more heating elements 18 operate only when needed. Sensors 19 may be accelerometers, temperature sensors, position sensors, load sensors, strain sensors, or combinations thereof. One or more sensors 19 may be disposed in / on the hub, nacelle, and / or blades for detecting icing or the condition of impending icing. Sensor 19 may be one or more of a liquid water content sensor, an ice detection sensor, an air pressure sensor, a surface resistance or impedance sensor.

[0119] In some examples, one or more sensors 19 are positioned away from the blade connection member 6 and the pretensioning member 8, for example, on a portion of the blade 5, on the nacelle 3, or on the hub 4. The anti-icing system and / or de-icing system 17 may include one or more weather sensors (e.g., external to the wind turbine 1) that can detect the condition of the turbine 1.

[0120] exist Figure 6 In this example, only one sensor 19 is set, but it should be understood that any number of sensors 19 can be set. Reference will be made later. Figure 8 and Figure 9 Let's have a discussion. Figure 8 and Figure 9 This is a schematic diagram of a blade connecting member 6 and / or a pretensioning member 8 with different sensor arrangements.

[0121] exist Figure 8 In the example shown, multiple sensors 19 are provided together with corresponding blade connecting members 6 or pretensioning members 8. In the illustrated example, multiple sensors 19 are provided at multiple locations along the length of the corresponding blade connecting member 6 or pretensioning member 8. Figure 8In this configuration, sensors 19 are evenly distributed along the entire length of the respective blade connection member 6 or pretensioning member 8. In some examples, the multiple sensors 19 may not be evenly distributed. Providing multiple sensors 19 along the length of the blade connection member 6 or pretensioning member 8 provides information about the state of the blade connection member 6 or pretensioning member 8 at various locations. This improves the ability of the anti-icing system and / or de-icing system 17 to operate only when needed, such as when conditions at the blade connection member 6 and / or pretensioning member 8 are sufficient to indicate that the heating element 18 in the blade may be required, thereby reducing the energy waste that might occur if the heating element 18 operates when icing is not a problem. Furthermore, multiple sensors 19 increase the redundancy of the anti-icing system and / or de-icing system 17, because if one sensor fails, information can still be obtained from the other sensors 19.

[0122] refer to Figure 9 Alternative examples of blade connecting member 6 or pretensioning member 8 are shown. In this example, a sensor 19 is provided extending substantially the entire length of the respective blade connecting member 6 or pretensioning member 8. In this way, information about icing can be obtained over the entire length of the respective blade connecting member 6 or pretensioning member 8. In some examples, multiple sensors 19 extending along the entire length of the blade connecting member 6 or pretensioning member 8 may be provided (e.g., to increase the redundancy of the sensor arrangement). Distributed sensors (i.e., as shown) can be implemented. Figure 8 The combination of the sensor 19 (shown) and a slender sensor (i.e., extending substantially the entire length of the corresponding blade connecting member 6 or pretensioning member 8). The sensor 19 may be disposed on the outer surface 20 of the blade connecting member 6 or pretensioning member 8, embedded in the outer surface 20, or a combination of both.

[0123] It should be understood that, regarding Figure 8 and Figure 9 The sensor arrangement described can be applied to any of the examples discussed in this article.

[0124] refer to Figures 10 to 14Alternative examples of wind turbine 1 and blade connection member 6 and / or pretensioning member 8 are shown. The wind turbine 1 and blade connection member 6 and / or pretensioning member 8 shown are similar to those previously described, so only the differences will be discussed in detail. In these examples, blade connection member 6 and / or pretensioning member 8 includes a structural load-bearing non-conductive material 33 and a conductive material 29 for transmitting electricity along the power source path 28 between hub 4 and heating element 18. In the figures, blade connection member 6 and / or pretensioning member 8 only includes structural load-bearing non-conductive material 33 and conductive material 29, but it should be understood that other materials may be present. The structural load-bearing non-conductive material 33 can be any material suitable for supporting the blades 5 relative to each other but not conductive, such as a polymer like ultra-high molecular weight polyethylene (UHMWPE). The conductive material 29 can be any material suitable for conducting electricity, as described above. These examples of blade connection member 6 and / or pretensioning member 8 can provide electricity between hub 4 and heating element 18 without being made entirely of conductive material. Non-conductive materials are generally lighter than conductive materials, thereby reducing the weight of the blade connection member 6 and / or the pretensioning member 8 and the rotor load on the turbine 1, while still facilitating the convenient layout of the power source path 28 via the blade connection member 6 and / or the pretensioning member 8.

[0125] exist Figure 10 and Figure 11 In this process, the conductive material 29 is embedded within the non-conductive material 33 of the corresponding blade connecting member 6 or pre-tensioning member 8. Figure 11 As can be seen from the cross-sectional view, the non-conductive material 33 surrounds the conductive material 29 (e.g., completely surrounds or encapsulates the conductive material 29, such that the power source path 28 is surrounded by the non-conductive material 33). In some examples, the conductive material 29 may only be partially encapsulated. Figure 10 and Figure 11 The arrangement protects the conductive material 29 and thus the power source path 28 from damage (e.g. from precipitation, dust, and debris) and supports the conductive material 29 relative to the blade connecting member 6 or the pre-tensioning member 8 to provide power to the heating element 18 without the need for additional components to provide support.

[0126] Figure 12 An alternative configuration is illustrated in the example. A conductive material is attached to the outer surface 34 of the non-conductive material 33 of the corresponding blade connecting member 6 or pre-tensioning member 8. The conductive material 29 can be attached to the outer surface 34 by any suitable means, such as mechanical connection, bonding, welding, clamping, wrapping around the non-conductive material (e.g., in a helical structure), or a combination thereof. Attaching the conductive material 29 to the outer surface 34 of the non-conductive material 33 provides convenient access to the conductive material 29.

[0127] Figure 13A cross-sectional view of the blade connecting member 6 and / or pretensioning member 8 is shown, wherein conductive material 29 is attached to the outer surface 34 of non-conductive material 33. In this example, the conductive material 29 is coupled to the blade connecting member 6 and / or pretensioning member 8 outside the contour of the respective blade connecting member 6 or pretensioning member 8. The term "contour" refers to the contour defined by the core element (i.e., cable or non-conductive material 33) of the blade connecting member 6 or pretensioning member 8. Figure 6 In this figure, conductive material 29 is coupled to the outside of the contour, i.e., coupled to the outer surface 34. In the figure, conductive material 29 is secured to the outer surface 34 by a braided (or woven) sleeve 35. The braided sleeve 35 can wrap the conductive material 29 over the non-conductive material 33 to secure the conductive material 29 relative to the non-conductive material 33. The braided sleeve 35 can be used in combination with any other securing device, or in some examples it may not be present.

[0128] exist Figure 14 In one example, the conductive material 29 is coupled to the blade connecting member 6 and / or the pretensioning member 8 within the contour of the respective blade connecting member 6 or pretensioning member 8. In this example, the blade connecting member 6 or the pretensioning member 8 includes a recessed region defining a channel 36 or an aperture. The channel 36 may be defined in a non-conductive material 33 (i.e., the outer surface 34 of the non-conductive material includes the recessed region). The conductive material 29 is received and supported in the channel 36 (i.e., supported by the non-conductive material 33). The conductive material 29 may be fixedly attached to the channel 36 (e.g., by any of the methods described above), and / or may be press-fitted into the channel 36. In some examples, a braided sleeve 35 may be additionally or alternatively provided to secure the conductive material 29 in the channel 36.

[0129] The anti-icing system and / or de-icing system 17 has been described as providing protection through various configurations of the blade connection member 6 and / or pretensioning member 8. It should be understood that any combination of the above examples can be implemented. For example, different blade connection members 6 and / or pretensioning members 8 in the wind turbine 1 may include any combination of the features of these examples.

[0130] refer to Figure 15 An example power distribution system 25 is shown. As previously described, the power distribution system 25 includes a power distributor 26 located in the hub 4. The system 25 may also include a lightning discharge filter system 32 located in the hub 4. Power can be supplied to the power distributor 26 from various sources. Figure 15In this example, power 45 is supplied from a distributed control node 41 in the hub 4 to a power distributor 26. The distributed control node 41 can receive power from a generator in the nacelle 3 or from any source outside the hub 4. The distributed control node 41 can provide control signals 39 to the power distributor 26 regarding conditions at or near the blade 5. The distributed control node 41 can be configured to receive data from sensor 19 and, based on that data, issue control signals 39 to the power distributor 26. For example, if it is determined based on data from sensor 19 that ice may be accumulating on the blade 5, the distributed control node 41 can transmit control signals 39 to the distribution box to begin supplying power to the heating element 18 along the power source path 28 laid along the blade connecting member 6 and / or pre-tensioning member 8. The control signal 39 can also instruct the power distributor 26 to increase the power supplied to the heating element 18 (e.g., to increase the temperature generated by the heating element 18 at the blade surface 10).

[0131] The power distributor 26 can also be coupled to the lightning discharge filter system 32 within the hub 4. In this way, in the event of a lightning strike to the lightning arrester, the current 38 from the lightning strike is directed from the lightning arrester to the power distributor 26 (e.g., via the aforementioned power source path 28), and then to the lightning discharge filter system 32. The lightning discharge filter system 32 then directs the lightning current 37 to ground (e.g., via the nacelle 3 and tower 2) and protects the power supply to the blade heating elements 18. Positioning the power distributor 26, the lightning discharge filter system 32, and the distributed control node 41 within the hub 4 provides protection for these critical components and reduces the required electrical components (i.e., eliminating the need for separate distribution boxes and / or discharge filters on each blade connection member 6 and / or pretension member 8 or on each blade), thereby reducing the mechanical load on the wind turbine 1.

[0132] Although the invention has been described above with reference to one or more preferred embodiments, it should be understood that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

1. A pitch-controlled wind turbine (1) comprising a tower (2), a nacelle (3) mounted on the tower (2), a hub (4) rotatably mounted on the nacelle (3), and at least three wind turbine blades (5), wherein, Each wind turbine blade (5) extends between its tip (12) and its root (11) which is connected to the hub (4) via a pitch mechanism; The wind turbine (1) further includes at least three blade connection members (6), each blade connection member (6) extending from a connection point (7a, 7b) on a wind turbine blade (5) toward a connection point (7a, 7b) on an adjacent wind turbine blade (5), wherein the connection points (7a, 7b) on a given wind turbine blade (5) are arranged at a distance from the root end (11) and at a distance from the tip end (12) of the wind turbine blade (5); At least three pretensioning members (8), each pretensioning member (8) is connected to one of the blade connecting members (6) and connected to the hub (4) via a tensioning device (9), the tensioning device (9) providing radial movement of the radially inner end of the pretensioning member (8) relative to the axis of rotation of the hub (4) due to the extension or retraction of the tensioning device (9), thereby providing pretension in the blade connecting member (6) to which it is connected; and An anti-icing system and / or a de-icing system (17) includes one or more heating elements (18) for protecting one or more wind turbine blades (5). One or more power source paths (28) for the anti-icing system or de-icing system (17) are arranged between the hub (4) and the heating element (18) along at least one of the blade connecting member (6) and the pre-tensioning member (8).

2. The pitch-controlled wind turbine (1) according to claim 1, wherein, The blade connecting member (6) and / or the pretensioning member (8) include a conductive material (29), and the conductive material (29) is a structural load-bearing conductive material for transmitting power along the power source path (28) between the hub (4) and the heating element (18).

3. The pitch-controlled wind turbine (1) according to claim 1, wherein, The blade connecting member (6) and / or the pretensioning member (8) includes a structural load-bearing non-conductive material (33) and also includes a conductive material (29) for transmitting power along the power source path (28) between the hub (4) and the heating element (18).

4. The pitch-controlled wind turbine (1) according to claim 3, wherein, The conductive material (29) is embedded in the non-conductive material (33) of the corresponding blade connecting member (6) or pre-tensioning member (8).

5. The pitch-controlled wind turbine (1) according to claim 3, wherein, The conductive material (29) is attached to the outer surface (34) of the non-conductive material (33) of the corresponding blade connecting member (6) or pre-tensioning member (8).

6. The pitch-controlled wind turbine (1) according to claim 5, wherein, The conductive material (29) is coupled to the corresponding blade connecting member (6) or pretensioning member (8) inside or outside the contour of the non-conductive material (33) of the corresponding blade connecting member (6) or pretensioning member (8).

7. The pitch-controlled wind turbine (1) according to any one of claims 2 to 6, wherein, The blade connection member (6) and / or pretensioning member (8) having conductive material (29) also include a lightning protection system (30) configured to isolate the conductive material (39) from lightning current.

8. A pitch-controlled wind turbine (1) according to any one of the preceding claims, wherein, When power is transmitted along the power source path (28) between the hub (4) and the heating element (18), the power source path (28) provides residual or inherent heat to protect the blade connecting member (6) or the pretensioning member (8) from icing or to achieve de-icing (during the operation of the heating element (18)).

9. A pitch-controlled wind turbine (1) according to any one of the preceding claims, wherein, The anti-icing system or de-icing system (17) includes a power distribution system (25) for distributing power to each wind turbine blade (5), and wherein the power distribution system (25) includes a power distributor (26) housed in the hub (4).

10. A pitch-controlled wind turbine (1) according to any one of the preceding claims, wherein, The anti-icing system and / or de-icing system (17) includes one or more sensors (19) in or above one or more of the blade connection member (6) or pre-tensioning member (8) for detecting icing or conditions that are about to occur.

11. The pitch-controlled wind turbine (1) according to claim 10, wherein, The sensor (19) is one or more of the following: accelerometer, temperature sensor, position sensor, load sensor, liquid water content sensor, ice detection sensor, air pressure sensor, surface resistance or impedance sensor, or strain sensor.

12. The pitch-controlled wind turbine (1) according to claim 10 or 11, wherein, The one or more sensors (19) are provided at multiple locations along the length of the blade connecting member (6) or the pretensioning member (8), or the one or more sensors (19) are provided along substantially the entire length of the blade connecting member (6) or the pretensioning member (8).

13. A pitch-controlled wind turbine (1) according to any one of the preceding claims, wherein, The anti-icing system or de-icing system (17) includes a lightning protection system (30), which includes a lightning discharge filter system (32), preferably the lightning discharge filter system (32) is housed in the wheel hub (4).

14. A pitch-controlled wind turbine (1) according to any one of the preceding claims, wherein, The blade connecting member (6) and / or pretensioning member (8) includes at least one bearing (50) located at or toward the end of the respective blade connecting member (6) and / or pretensioning member (8), wherein the bearing (50) is non-conductive, and wherein the power source path (28) is decoupled from the respective blade connecting member (6) and / or pretensioning member (8) to be diverted around the at least one bearing (50).

15. The pitch-controlled wind turbine (1) according to claim 14, wherein, Each wind turbine blade (5) includes a leading edge (13), a leading edge extension (49), and a blade shell (53), wherein the leading edge extension (49) extends in front of the leading edge (13), and the connection points (7a, 7b) of the corresponding wind turbine blade (5) are located on the leading edge extension (49) in front of the leading edge (13), and each wind turbine blade (5) also includes a corresponding fairing (20) extending at least above the leading edge extension (49), wherein the power supply path (28) is decoupled from the corresponding blade connection member and diverted around the bearing (50) within the fairing (20).

Images