Sectional type blade of ultra-large wind wheel and connecting method of sectional type blade

Abstract

The invention provides an ultra-large wind wheel segmented blade and a connecting method thereof, the ultra-large wind wheel segmented blade comprises a first-stage segmented blade, the end of the first-stage segmented blade is connected with a second-stage segmented blade through a first-stage combined butt joint, the end of the second-stage segmented blade is connected with a third-stage segmented blade through a second-stage combined butt joint, and the third-stage segmented blade is connected with a second-stage combined butt joint. The end of the third-stage segmented blade is connected with a fourth-stage segmented blade through a third-stage combined butt joint; the first-stage segmented blade, the second-stage segmented blade, the third-stage segmented blade and the fourth-stage segmented blade respectively adopt a subdivision and combination structural form, and each segment of blade comprises a segmented blade segment A and a segmented blade segment B. The sectional type blade design is adopted, the blades are manufactured in a small module mode, production is completed in a factory with the standard size, and large-scale factory buildings and special equipment are not needed. Each section of the blade can be independently manufactured and tested in a factory, and the quality of each section is ensured.

Description

Technical Field

[0001] The present invention relates to the field of wind power generation equipment, and particularly to an extra-large wind turbine segmented blade and a connection method thereof. Background Art

[0002] With the continuous progress of wind power generation technology, the power of horizontal-axis wind turbines is also increasing continuously. In order to capture more wind energy, the blade length of wind turbines has also increased accordingly. Currently, 6-megawatt (MW) wind turbines have emerged on the market, and larger power 7MW to 12MW wind turbines are also in the research and development stage. The blade lengths of these high-power wind turbines are expected to be between 65 meters and 110 meters. However, the blade length has encountered unprecedented challenges in the manufacturing process and transportation process.

[0003] The difficulties in manufacturing mainly manifest in the following aspects: The mold manufacturing and material processing of ultra-long blades require extremely high precision and strength, which pose higher requirements on existing manufacturing equipment and technologies. Secondly, the longer the blade, the more complex the design and manufacturing of its internal structure, and it is necessary to ensure the stability and durability of the blade during long-term operation. In terms of transportation, the size and weight of ultra-long blades exceed the load-bearing capacity of conventional transportation tools, and special transportation methods and route planning are required. In addition, the blade is easily damaged during transportation, which may affect the performance and lifespan of the blade. Summary of the Invention

[0004] Modern wind turbines are developing towards the direction of large-scale, and the large-scale of the blade will bring a series of prominent problems such as manufacturing, transportation, installation, and maintenance. Developing segmented composite blades is exactly a goal pursued by people. In view of this, the present invention aims at a key problem of the docking joint of large segmented blades, and proposes an extra-large wind turbine segmented blade and a connection method thereof.

[0005] In order to achieve the above technical features, the object of the present invention is achieved as follows: An extra-large wind turbine segmented blade includes a first-stage segmented blade. The end of the first-stage segmented blade is connected to a second-stage segmented blade through a first-stage combined docking joint. The end of the second-stage segmented blade is connected to a third-stage segmented blade through a second-stage combined docking joint. The end of the third-stage segmented blade is connected to a fourth-stage segmented blade through a third-stage combined docking joint. The first-stage segmented blade, the second-stage segmented blade, the third-stage segmented blade, and the fourth-stage segmented blade all respectively adopt a split-combined structural form, and each blade segment contains a segmented blade A segment and a segmented blade B segment.

[0006] Preferably, the first-stage combined docking joint is formed by connecting two first joint unit modules with the same structure along the through-hole part in the middle of the first-stage joint unit rib plate. Each first joint unit module is composed of a first joint unit connecting column, a first left-side joint unit, a first right-side joint unit, and a first tightening bolt; The second-stage combined docking joint is formed by connecting two second joint unit modules with the same structure, one large and one small, along the through-hole part in the middle of the second-stage joint unit rib plate. The second joint unit module is composed of a second joint unit connecting column, a second left-side joint unit, a second right-side joint unit, and a second tightening bolt; The third-stage combined docking joint is formed by connecting a third joint unit module and a screw column along the through-hole part in the middle of the third-stage joint unit rib plate. The third joint unit module is composed of a third joint unit connecting column, a third left-side joint unit, a third right-side joint unit, and a third tightening bolt; The first joint unit module, the second joint unit module, and the third joint unit module have the same structure. Among them, the size of the third joint unit module is half of the size of the first joint unit module, the size of the small second joint unit module is the same as that of the third joint unit module, and the size of the large second joint unit module is the same as that of the first joint unit module.

[0007] Preferably, the first left-side joint unit and the first right-side joint unit are horizontally connected by the first-stage joint unit rib plate. Each of the first left-side joint unit and the first right-side joint unit has 6 round holes connected to 6 first joint unit connecting columns by bolts; the first joint unit connecting column is fixed to the first tightening bolt by a bolt and passes through the connecting square hole of the first-stage joint unit rib plate. Both ends of the first tightening bolt have helical threads with opposite rotation directions, so that each joint unit module conforms to the blade airfoil and is connected into an integral structure by 3 first tightening bolts with opposite left and right rotation directions; The second left-side joint unit and the second right-side joint unit are horizontally connected by the second-stage joint unit rib plate. Each of the second left-side joint unit and the second right-side joint unit has 6 round holes connected to 6 second joint unit connecting columns by bolts; the second joint unit connecting column is fixed to the second tightening bolt by a bolt and passes through the connecting square hole of the second-stage joint unit rib plate. Both ends of the second tightening bolt have helical threads with opposite rotation directions, so that each joint unit module conforms to the blade airfoil and is connected into an integral structure by 3 second tightening bolts with opposite left and right rotation directions; The third left joint unit and the third right joint unit are horizontally connected by the third-stage joint unit rib plate. Each of the third left joint unit and the third right joint unit has 6 round holes and is bolted to 6 third joint unit connecting columns. The third joint unit connecting columns are fixed to the third tightening bolts by bolts and pass through the connecting square holes of the third-stage joint unit rib plate. Both ends of the third tightening bolts have helical threads with opposite helix directions, so that each joint unit module conforms to the blade airfoil and is connected into an integral structure by 3 third tightening bolts with opposite left and right helix directions and the screw columns.

[0008] Preferably, the first joint unit connecting column is formed by an upper column, a bolt interface, a connecting arc, and a lower column. The connecting arc can rotate around the center point of the arc along the column direction between the upper column and the lower column on the corresponding side.

[0009] Preferably, the first left joint unit is composed of an upper round plate, an elastic support frame, and a lower round plate. 6 round through holes of the same size are opened on the upper round plate, and 3 strip through holes of the same size are opened on the lower round plate.

[0010] Preferably, the A section of the segmented blade includes the blade A sections that respectively constitute the first-stage segmented blade, the second-stage segmented blade, the third-stage segmented blade, and the fourth-stage segmented blade. The B section of the segmented blade includes the blade B sections that respectively constitute the first-stage segmented blade, the second-stage segmented blade, the third-stage segmented blade, and the fourth-stage segmented blade.

[0011] Preferably, each segmented blade of the blade A section and the blade B section is provided with a rib plate isolation compartment. An airbag is arranged in each central compartment, and the pipeline is buried into the through holes of each rib plate and connected to the airbag for later inflation and maintenance. When the wind speed is lower than the cut-in wind speed, the airbag is inflated by 30%. When the wind speed is between the cut-in wind speed and the rated wind speed, the airbag will slowly inflate and adjust the pressure with the increase of the wind speed. When the wind speed is between the rated wind speed and the cut-out wind speed, the airbag will slowly deflate with the increase of the wind speed. When the wind speed is higher than the cut-out wind speed, the airbag is completely deflated.

[0012] Preferably, through holes are opened on each of the first-stage joint unit rib plates, the second-stage joint unit rib plates, and the third-stage joint unit rib plates located on the blade section bearing frame, so that the first tightening bolt, the second tightening bolt, and the third tightening bolt are connected to the outside through the through holes, so as to control the rotation direction by inserting a hex wrench into the hex nuts of the first tightening bolt, the second tightening bolt, and the third tightening bolt through the through holes on the first-stage joint unit rib plates, the second-stage joint unit rib plates, and the third-stage joint unit rib plates.

[0013] On the other hand, the present invention provides a connection method for a segmented blade of an extra-large wind turbine, including the following installation steps: a) Factory prefabrication of segmented blades: The blade is designed into four segments, and each segment contains various components of segmented blade section A, segmented blade section B, and a combined docking joint; b) Installation of combined docking joints at all levels: Twist two first joint unit connecting columns in opposite directions into the central position of the first tightening bolt, combine three portions, then place the first tightening bolt of each portion at the through-hole on the rib plate of the first-level joint unit. After placement, reverse-adjust the 3 first tightening bolts so that the 6 first joint unit connecting columns correspond one by one to the 6 through-holes of the first right-side joint unit and the first left-side joint unit, and then weld them together; Splice two docking joints on the rib plate of the first-level joint unit of the combined docking joint to complete the assembly of the first-level combined docking joint; Complete the assembly of the second-level combined docking joint and the third-level combined docking joint in the same steps; c) Installation and connection of the blade as a whole including an airbag: Fill the airbag with inert gas helium, place the airbag in the rib plate gap between segmented blade section A and segmented blade section B, bury the pipeline into the through-hole of each rib plate and connect it to the airbag, and then paste sections A and B of each blade on-site, and use the blade outer shape female mold to complete the final aerodynamic shape forming of the blade; d) In step a), use the prefabricated first-level combined docking joint, second-level combined docking joint, and third-level combined docking joint to perform on-site pasting at the docking positions corresponding to the first-level segmented blade, second-level segmented blade, third-level segmented blade, and fourth-level segmented blade. Use a mold positioned by threaded steel to perform hole diameter positioning on each side of the docking joint, and then bury both sides of the docking joint into the corresponding blade through-holes; e) In step b), insert a hex wrench through the through-hole on the rib plate of the first-level joint unit into the hex nut of the first tightening bolt and rotate it to bend the six first joint unit connecting columns inward, so that the first left-side joint unit and the first right-side joint unit are bent and deformed under the tension of the six first joint unit connecting columns, and are stuck at the central through-hole of the segmented blade, so that the first-level combined docking joint connects the first-level segmented blade and the second-level segmented blade. Complete the connection of the second-level combined docking joint connecting the second-level segmented blade and the third-level segmented blade in the same steps; The third-level combined docking joint connects the third-level segmented blade and the fourth-level segmented blade.

[0014] Preferably, it includes the following maintenance steps: a) Insert a hex wrench through the through-hole on the rib plate of the first-stage joint unit into the hex nut of the first tightening bolt and rotate it to straighten the six first joint unit connecting columns from the bent state, so that the first right joint unit and the first left joint unit are straightened from the bent deformation state by the thrust of the six first joint unit connecting columns, and separate the first-stage segmented blade and the second-stage segmented blade by the first-stage combined docking joint stuck at the central through-hole of the segmented blade. Complete the separation of the second-stage segmented blade and the third-stage segmented blade by the second-stage combined docking joint in the same steps; separate the third-stage segmented blade and the fourth-stage segmented blade by the third-stage combined docking joint, and complete the subsequent maintenance of the first-stage combined docking joint, the second-stage combined docking joint, and the third-stage combined docking joint.

[0015] b) The rib plate at the docking part of the segmented blade and the joint unit is provided with a through-hole. Connect the air injection device to the pipeline through the through-hole, bury the pipeline in the through-holes of each rib plate and connect it to the airbag, and the air injection device inflates the airbag through the pipeline for maintenance.

[0016] The present invention has the following beneficial effects: 1. The present invention adopts a segmented blade design to manufacture the blades in smaller modules, enabling production to be completed in a factory with standard dimensions without the need for large-scale workshops and special equipment. Each segment of the blade can be independently manufactured and tested in the factory to ensure the quality of each part. In terms of transportation, the segmented blades can be disassembled into multiple smaller parts and transported to the installation site of the wind farm by conventional transportation tools. After arriving at the site, the engineering staff can accurately dock the various segments of the blade according to the design requirements to restore the complete blade structure. The completed docked blade is then installed with the main unit of the wind turbine, thus greatly simplifying the entire installation process.

[0017] 2. The present invention adopts a segmented blade design, which not only solves the processing and manufacturing problems of ultra-long blades, but also reduces transportation costs and risks, and improves the flexibility and efficiency of wind turbine installation. This design method provides new possibilities for the development of the wind power generation industry and helps to promote the further innovation and application of wind power generation technology.

[0018] 3. In the present invention, by providing an airbag, when the wind speed is lower than the cut-in wind speed, the airbag is inflated to 30% to maintain a certain pressure, so as to provide sufficient blade stiffness and maintain the shape and stability of the blade; when the wind speed is between the cut-in wind speed and the rated wind speed, the airbag is slowly inflated to adjust the pressure as the wind speed increases, optimizing the aerodynamic performance of the blade, improving the power generation efficiency, and ensuring that the blade maintains a good working state under changing wind speeds; when the wind speed is between the rated wind speed and the cut-out wind speed, the airbag is slowly deflated as the wind speed increases to reduce the blade stiffness, reduce the blade load and avoid excessive stress, enabling it to better withstand wind loads under extreme wind speeds; when the wind speed is higher than the cut-out wind speed, the airbag is completely deflated and the wind turbine will automatically stop running to prevent overload and potential damage.

[0019] 4. The introduction of the airbag in the present invention significantly reduces the weight of the blade. In the hollow part of the segmented blade, the airbag is filled with a light gas such as air or helium to reduce the weight of the entire blade structure. The lightweight not only helps to reduce the difficulty of transportation and installation, but also reduces the requirements of the wind turbine on the tower and foundation structure, thereby reducing the overall cost. Since the blade continuously bears cyclic loads during operation, this may cause fatigue cracks in metal components. By providing airbags at key positions, these cyclic loads can be effectively absorbed and dispersed, reducing the stress concentration in metal components and extending the service life of the blade. The design of the segmented blade makes the blade more flexible during the manufacturing process. The use of the airbag not only reduces the weight, but also increases the flexibility of the blade, making it more resistant to strong winds and extreme weather conditions. The reduced weight makes the repair and replacement work more convenient when the blade is damaged.

[0020] 5. The invention of the segmented wind turbine blade, through the design including an airbag, not only reduces the weight of the blade, alleviates metal fatigue, but also improves the durability and maintenance convenience of the blade, thus bringing economic benefits to the wind power industry, and the present invention can be used under various working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with the drawings and embodiments.

[0022] Figure 1 It is an exploded view of the segmented blade of the present invention.

[0023] Figure 2 It shows a more detailed exploded view of the segmented blade.

[0024] Figure 3 It is a schematic diagram of the first-stage combined docking joint of the present invention.

[0025] Figure 4 It shows a more detailed schematic diagram of the connecting column.

[0026] Figure 5 The schematic diagram of the joint unit is shown in more detail.

[0027] Figure 6 This is the schematic diagram of the bending structure of the joint unit of the present invention. Specific embodiments

[0028] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0029] Embodiment 1: Refer to Figure 1-6 , a super-large wind turbine segmented blade, including a first-stage segmented blade 1. The end of the first-stage segmented blade 1 is connected to a second-stage segmented blade 3 through a first-stage combined docking joint 2. The end of the second-stage segmented blade 3 is connected to a third-stage segmented blade 5 through a second-stage combined docking joint 4. The end of the third-stage segmented blade 5 is connected to a fourth-stage segmented blade 7 through a third-stage combined docking joint 6. The first-stage segmented blade 1, the second-stage segmented blade 3, the third-stage segmented blade 5, and the fourth-stage segmented blade 7 all adopt a split-combined structural form. Each blade segment contains a segmented blade A segment and a segmented blade B segment. By adopting the above-mentioned segmented blade, the blade can be manufactured in smaller modules, realizing production in a factory with standard dimensions without the need for large-scale workshops and special equipment. Each segment of the blade can be independently manufactured and tested in the factory to ensure the quality of each part. In terms of transportation, the segmented blade can be disassembled into multiple smaller parts and transported to the installation site of the wind farm by conventional transportation tools. After arriving at the site, engineers can accurately dock the segments of the blade according to the design requirements to restore the complete blade structure. The completed docked blade is then installed with the main unit of the wind turbine, thus greatly simplifying the entire installation process.

[0030] Furthermore, the first-stage combined docking joint 2 is formed by connecting two first joint unit modules with the same structure along the through-hole part in the middle of the first-stage joint unit rib plate 2C. Each first joint unit module is composed of first joint unit connecting columns 2A, 2A', first left joint units 2B, 2B', first right joint units 2D, 2D' and first tightening bolts 2E, 2E'. The second-stage combined docking joint 4 is formed by connecting two second joint unit modules with the same structure, one large and one small, along the through-hole part in the middle of the second-stage joint unit rib plate 4C. The second joint unit module is composed of second joint unit connecting columns 4A, 4A', second left joint units 4B, 4B', second right joint units 4D, 4D' and second tightening bolts 4E, 4E'. The third-stage combined docking joint 6 is formed by connecting a third joint unit module and a screw column 6F along the through-hole part in the middle of the third-stage joint unit rib plate 6C. The third joint unit module is composed of a third joint unit connecting column 6A', a third left joint unit 6B', a third right joint unit 6D' and a third tightening bolt 6E'. The first joint unit module, the second joint unit module and the third joint unit module have the same structure. Among them, the size of the third joint unit module is half of the size of the first joint unit module, the size of the small second joint unit module is the same as that of the third joint unit module, and the size of the large second joint unit module is the same as that of the first joint unit module. Through the above docking joints, rapid docking between segmented blades can be achieved.

[0031] Furthermore, the first left joint units 2B, 2B' and the first right joint units 2D, 2D' are horizontally connected by the first-stage joint unit rib plates 2C. Each of the first left joint units 2B, 2B' and the first right joint units 2D, 2D' has 6 round holes and is connected to 6 first joint unit connecting columns 2A, 2A' by bolts. The first joint unit connecting columns 2A, 2A' are fixed to the first tightening bolts 2E, 2E' by bolts and pass through the connecting square holes of the first-stage joint unit rib plates 2C. The two ends of the first tightening bolts 2E, 2E' have helical threads with opposite helix directions, so that each joint unit module conforms to the blade airfoil, and they are connected into an integral structure by 3 first tightening bolts 2E, 2E' with opposite left and right helix directions. The second left joint units 4B, 4B' and the second right joint units 4D, 4D' are horizontally connected by the second-stage joint unit rib plates 4C. Each of the second left joint units 4B, 4B' and the second right joint units 4D, 4D' has 6 round holes and is connected to 6 second joint unit connecting columns 4A, 4A' by bolts. The second joint unit connecting columns 4A, 4A' are fixed to the second tightening bolts 4E, 4E' by bolts and pass through the connecting square holes of the second-stage joint unit rib plates 4C. The two ends of the second tightening bolts 4E, 4E' have helical threads with opposite helix directions, so that each joint unit module conforms to the blade airfoil, and they are connected into an integral structure by 3 second tightening bolts 4E, 4E' with opposite left and right helix directions. The third left joint unit 6B' and the third right joint unit 6D' are horizontally connected by the third-stage joint unit rib plates 6C. Each of the third left joint unit 6B' and the third right joint unit 6D' has 6 round holes and is connected to 6 third joint unit connecting columns 6A' by bolts. The third joint unit connecting columns 6A' are fixed to the third tightening bolt 6E' by bolts and pass through the connecting square holes of the third-stage joint unit rib plates 6C. The two ends of the third tightening bolt 6E' have helical threads with opposite helix directions, so that each joint unit module conforms to the blade airfoil, and they are connected into an integral structure by 3 third tightening bolts 6E' with opposite left and right helix directions and the screw column 6F. Through the above specific connection method, it is convenient for subsequent on-site assembly and docking of the blades, improving the assembly efficiency. Moreover, it is convenient for subsequent maintenance in case of damage.

[0032] Furthermore, the first joint unit connecting column 2A is formed by connecting the upper column 2A1, the bolt interface 2A2, the connecting arc 2A3, and the lower column 2A4. The connecting arc 2A3 can rotate around the center point of the connecting arc 2A3 along the column direction between the upper column 2A1 and the lower column 2A4 on the corresponding side. Provide a pulling force to pull the two ends of the first left joint unit 2B and the first right joint unit 2D, causing them to deform and get stuck at the central through hole of the segmented blade.

[0033] Further, the first left joint unit 2B is composed of an upper circular plate 2B1, an elastic support frame 2B3, and a lower circular plate 2B5; six circular through-holes 2B2 of the same size are formed on the upper circular plate 2B1, and three strip-shaped through-holes 2B4 of the same size are formed on the lower circular plate 2B5.

[0034] Preferably, six circular through-holes 2B2 of the same size are formed on the upper circular plate 2B1, which are designed by omitting the left and right points among the eight points where the circular plate is evenly stressed, so as to achieve the optimal stress and the longest distance between the corresponding strip-shaped through-holes; three strip-shaped through-holes 2B4 of the same size are formed on the lower circular plate 2B5, the width of the through-holes is the same as that of the circular through-holes 2B2, and the length is the longest distance between the corresponding circular through-holes. The upper side column 2A1 of the connecting column 2A of the first joint unit can be connected to the circular through-holes 2B2 on the upper circular plate 2B1 through the strip-shaped through-holes 2B4, and the connecting arc 2A3 can be moved along the strip direction of the strip-shaped through-holes 2B4 to control the stretching of the elastic support frame 2B3.

[0035] Further, the segmented blade A section includes blade A sections 1A, 3A, 5A, and 7A that respectively form the first-stage segmented blade 1, the second-stage segmented blade 3, the third-stage segmented blade 5, and the fourth-stage segmented blade 7; the segmented blade B section includes blade B sections 1B, 3B, 5B, and 7B that respectively form the first-stage segmented blade 1, the second-stage segmented blade 3, the third-stage segmented blade 5, and the fourth-stage segmented blade 7.

[0036] Further, within each segmented blade of blade A segments 1A, 3A, 5A, and 7A and blade B segments 1B, 3B, 5B, and 7B, there are rib plates 3A2 to isolate compartments. An airbag 8 is provided in each central compartment. The pipeline is buried into the through-holes 3A1 of each rib plate 3A2 and connected to the airbag 8 for later inflation and maintenance. When the wind speed is lower than the cut-in wind speed, the airbag is inflated to 30%. When the wind speed is between the cut-in wind speed and the rated wind speed, the airbag 8 will slowly inflate and adjust the pressure as the wind speed increases. When the wind speed is between the rated wind speed and the cut-out wind speed, the airbag 8 slowly deflates as the wind speed increases. When the wind speed is higher than the cut-out wind speed, the airbag 8 is completely deflated. The introduction of the above airbag 8 significantly reduces the weight of the blade. In the hollow part of the segmented blade, the airbag is filled with a light gas, such as air or helium, to reduce the weight of the entire blade structure. Lightweight not only helps reduce the difficulty of transportation and installation but also reduces the requirements of the wind turbine on the tower and foundation structure, thus reducing the overall cost. Since the blade continuously bears cyclic loads during operation, this may cause fatigue cracks in metal components. By setting airbags at key positions, these cyclic loads can be effectively absorbed and dispersed, reducing the stress concentration of metal components and extending the service life of the blade. The design of the segmented blade makes the blade more flexible during the manufacturing process. The use of airbags not only reduces the weight but also increases the flexibility of the blade, making it more resistant to strong winds and extreme weather conditions. The reduced weight makes the maintenance and replacement work more convenient when the blade is damaged.

[0037] Further, through-holes are provided on each first-stage joint unit rib plate 2C, second-stage joint unit rib plate 4C, and third-stage joint unit rib plate 6C of the blade cross-section load-bearing frame, so that the first tightening bolts 2E, 2E', second tightening bolts 4E, 4E', and third tightening bolts 6E' are connected to the outside through the through-holes, so as to control the rotation direction by inserting a hex wrench into the hex nuts of the first tightening bolts 2E, 2E', second tightening bolts 4E, 4E', and third tightening bolts 6E' through the through-holes on the first-stage joint unit rib plate 2C, second-stage joint unit rib plate 4C, and third-stage joint unit rib plate 6C.

[0038] Embodiment 2: A connection method for a super-large wind turbine segmented blade, including the following installation steps: a) Factory prefabrication of segmented blades: The blade is designed into four segments, each containing the components of segmented blade A segment, segmented blade B segment, and combined docking joints; b) Install combined butt joints at all levels: Twist two first joint unit connecting columns 2A in opposite directions and screw them into the central position of the first tightening bolt 2E, combine three sets, then place the first tightening bolt 2E of each set at the through holes on the rib plate 2C of the first-stage joint unit. After placing, reverse-adjust 3 first tightening bolts 2E so that the 6 first joint unit connecting columns 2A correspond one by one to the 6 through holes of the first right-side joint unit 2D and the first left-side joint unit 2B, and then weld them together; splice two butt joints on the rib plate 2C of the first-stage joint unit of the combined butt joint to complete the assembly of the first-stage combined butt joint 2; complete the assembly of the second-stage combined butt joint 4 and the third-stage combined butt joint 6 in the same steps; c) Install and connect the overall blade including the airbag: Fill the airbag 8 with inert gas helium, place the airbag 8 in the rib plate gap between the segmented blade A section and the segmented blade B section, bury the pipeline into the through holes of each rib plate and connect it to the airbag 8, and then paste the A section and B section of each blade on-site, and use the blade outer shape female mold to complete the final aerodynamic shape forming of the blade; d) In step a), use the prefabricated first-stage combined butt joint 2, second-stage combined butt joint 4, and third-stage combined butt joint 6 to paste on-site at the docking positions corresponding to the first-stage segmented blade 1, second-stage segmented blade 3, third-stage segmented blade 5, and fourth-stage segmented blade 7. Use a mold positioned by threaded steel to position the hole diameter on each side of the butt joint, and then bury both sides of the butt joint into the corresponding blade through holes; e) In step b), insert a hexagonal wrench through the through hole on the rib plate 2C of the first-stage joint unit to the hexagonal nut of the first tightening bolt 2E and rotate it to bend the six first joint unit connecting columns 2A inward, so that the first left-side joint unit 2B and the first right-side joint unit 2D are bent and deformed under the tension of the six first joint unit connecting columns 2A and are stuck at the central through hole of the segmented blade, so that the first-stage combined butt joint 2 connects the first-stage segmented blade 1 and the second-stage segmented blade 3. Complete the connection of the second-stage combined butt joint 4 to the second-stage segmented blade 3 and the third-stage segmented blade 5 in the same steps; the third-stage combined butt joint 6 connects the third-stage segmented blade 5 and the fourth-stage segmented blade 7.

[0039] Example 3: When damage occurs at the joint part and repair is needed, the repair can be conveniently achieved, and the specific repair steps are as follows: a) Insert the hexagon wrench through the through-hole on the rib plate 2C of the first-stage joint unit into the hexagon nut of the first tightening bolt 2E and rotate it to straighten the six first joint unit connecting columns 2A from the bent state, so that the first right joint unit 2D and the first left joint unit 2B are straightened by the thrust of the six first joint unit connecting columns 2A from the bent and deformed state, and the first-stage combined docking joint 2 stuck at the central through-hole of the segmented blade separates the first-stage segmented blade 1 and the second-stage segmented blade 3. The same steps are used to complete the separation of the second-stage combined docking joint 4 from the second-stage segmented blade 3 and the third-stage segmented blade 5; the third-stage combined docking joint 6 separates the third-stage segmented blade 5 and the fourth-stage segmented blade 7, and the subsequent maintenance of the first-stage combined docking joint 2, the second-stage combined docking joint 4, and the third-stage combined docking joint 6 is completed.

[0040] b) The rib plate 3A2 at the docking part of the segmented blade and the joint unit is provided with a through-hole 3A1. Connect the air injection device to the pipeline through the through-hole 3A1, bury the pipeline in the through-hole 3A1 of each rib plate and connect it to the airbag 8, and the air injection device inflates the airbag 8 through the pipeline for maintenance.

Claims

1. A super-large wind turbine segmented blade, characterized in that: It includes a first-stage segmented blade (1). The end of the first-stage segmented blade (1) is connected to a second-stage segmented blade (3) through a first-stage combined docking joint (2). The end of the second-stage segmented blade (3) is connected to a third-stage segmented blade (5) through a second-stage combined docking joint (4). The end of the third-stage segmented blade (5) is connected to a fourth-stage segmented blade (7) through a third-stage combined docking joint (6). The first-stage segmented blade (1), the second-stage segmented blade (3), the third-stage segmented blade (5), and the fourth-stage segmented blade (7) all adopt a split-combined structural form. Each blade segment contains a segmented blade A segment and a segmented blade B segment.

2. The super-large wind turbine segmented blade according to claim 1, wherein: The first-stage combined docking joint (2) is formed by connecting two first joint unit modules with the same structure along the through-hole part in the middle of the first-stage joint unit rib plate (2C). Each first joint unit module consists of first joint unit connecting columns (2A)(2A'), first left-side joint units (2B)(2B'), first right-side joint units (2D)(2D'), and first tightening bolts (2E)(2E'). The second-stage combined docking joint (4) is formed by connecting two second joint unit modules with the same structure, one large and one small, along the through-hole part in the middle of the second-stage joint unit rib plate (4C). The second joint unit module consists of second joint unit connecting columns (4A)(4A'), second left-side joint units (4B)(4B'), second right-side joint units (4D)(4D'), and second tightening bolts (4E)(4E'). The third-stage combined docking joint (6) is formed by connecting a third joint unit module and a screw column (6F) along the through-hole part in the middle of the third-stage joint unit rib plate (6C). The third joint unit module consists of a third joint unit connecting column (6A'), a third left-side joint unit (6B'), a third right-side joint unit (6D'), and a third tightening bolt (6E'). The first joint unit module, the second joint unit module, and the third joint unit module have the same structure. Among them, the size of the third joint unit module is half of the size of the first joint unit module. The size of the small second joint unit module is the same as that of the third joint unit module, and the size of the large second joint unit module is the same as that of the first joint unit module.

3. The super-large wind turbine segmented blade according to claim 2, wherein: The first left joint unit (2B) (2B') and the first right joint unit (2D) (2D') are horizontally connected by a first-stage joint unit rib plate (2C). Each of the first left joint unit (2B) (2B') and the first right joint unit (2D) (2D') has 6 round holes which are bolted to 6 first joint unit connecting columns (2A) (2A'). The first joint unit connecting columns (2A) (2A') are fixed to the first tightening bolts (2E) (2E') by bolts and pass through the connecting square holes of the first-stage joint unit rib plate (2C). The two ends of the first tightening bolts (2E) (2E') have helical threads with opposite helix directions, enabling each joint unit module to conform to the blade airfoil, and they are connected into an integral structure by 3 first tightening bolts (2E) (2E') with opposite left and right helix directions. The second left joint unit (4B) (4B') and the second right joint unit (4D) (4D') are horizontally connected by a second-stage joint unit rib plate (4C). Each of the second left joint unit (4B) (4B') and the second right joint unit (4D) (4D') has 6 round holes which are bolted to 6 second joint unit connecting columns (4A) (4A'). The second joint unit connecting columns (4A) (4A') are fixed to the second tightening bolts (4E) (4E') by bolts and pass through the connecting square holes of the second-stage joint unit rib plate (4C). The two ends of the second tightening bolts (4E) (4E') have helical threads with opposite helix directions, enabling each joint unit module to conform to the blade airfoil, and they are connected into an integral structure by 3 second tightening bolts (4E) (4E') with opposite left and right helix directions. The third left joint unit (6B') and the third right joint unit (6D') are horizontally connected by a third-stage joint unit rib plate (6C). Each of the third left joint unit (6B') and the third right joint unit (6D') has 6 round holes which are bolted to 6 third joint unit connecting columns (6A'). The third joint unit connecting columns (6A') are fixed to the third tightening bolts (6E') by bolts and pass through the connecting square holes of the third-stage joint unit rib plate (6C). The two ends of the third tightening bolts (6E') have helical threads with opposite helix directions, enabling each joint unit module to conform to the blade airfoil, and they are connected into an integral structure by 3 third tightening bolts (6E') with opposite left and right helix directions and a screw column (6F).

4. The super-large wind turbine segmented blade according to claim 2, wherein: The first joint unit connecting column (2A) is formed by connecting an upper column (2A1), a bolt interface (2A2), a connecting arc (2A3), and a lower column (2A4). The connecting arc (2A3) can rotate around the center point of the connecting arc (2A3) along the column direction between the corresponding upper column (2A1) and lower column (2A4).

5. The super-large wind turbine segmented blade according to claim 2, wherein: The first left joint unit (2B) is composed of an upper circular plate (2B1), an elastic support frame (2B3), and a lower circular plate (2B5); six circular through holes (2B2) of the same size are provided on the upper circular plate (2B1), and three strip-shaped through holes (2B4) of the same size are provided on the lower circular plate (2B5).

6. The super-large wind turbine segmented blade according to claim 1, characterized in that: The segmented blade A section includes blade A sections (1A), (3A), (5A), and (7A) that respectively constitute the first-stage segmented blade (1), the second-stage segmented blade (3), the third-stage segmented blade (5), and the fourth-stage segmented blade (7); The segmented blade B section includes blade B sections (1B), (3B), (5B), and (7B) that respectively constitute the first-stage segmented blade (1), the second-stage segmented blade (3), the third-stage segmented blade (5), and the fourth-stage segmented blade (7).

7. The super-large wind turbine segmented blade according to claim 6, wherein: Reinforcing plates (3A2) are provided inside each segmented blade of the blade A sections (1A), (3A), (5A), and (7A) and the blade B sections (1B), (3B), (5B), and (7B) to isolate compartments. An airbag (8) is provided in each central compartment, and the pipeline is buried into the through holes (3A1) of the reinforcing plates (3A2) and connected to the airbag (8) for later inflation and maintenance; When the wind speed is lower than the cut-in wind speed, the airbag is inflated by 30%; when the wind speed is between the cut-in wind speed and the rated wind speed, the airbag (8) slowly inflates and adjusts the pressure as the wind speed increases; when the wind speed is between the rated wind speed and the cut-out wind speed, the airbag (8) slowly deflates as the wind speed increases; when the wind speed is higher than the cut-out wind speed, the airbag (8) is completely deflated.

8. The super-large wind turbine segmented blade according to claim 2, wherein: Through holes are provided on each of the first-stage joint unit reinforcing plates (2C), the second-stage joint unit reinforcing plates (4C), and the third-stage joint unit reinforcing plates (6C) of the blade cross-section load-bearing frame, so that the first tightening bolts (2E) (2E'), the second tightening bolts (4E) (4E'), and the third tightening bolts (6E') are connected to the outside through the through holes, so as to control the rotation direction by inserting a hexagonal wrench into the hexagonal nuts of the first tightening bolts (2E) (2E'), the second tightening bolts (4E) (4E'), and the third tightening bolts (6E') through the through holes on the first-stage joint unit reinforcing plates (2C), the second-stage joint unit reinforcing plates (4C), and the third-stage joint unit reinforcing plates (6C).

9. The connecting method of a super-large wind turbine segmented blade according to any one of claims 2-8, characterized in that, The following installation steps are included: a) Factory prefabrication of segmented blades: The blade is designed into four segments, and each segment contains the components of the segmented blade A section, the segmented blade B section, and the combined docking joint; b) Install combined docking joints at all levels: Screw two connecting columns (2A) of the first joint unit in opposite directions into the center position of the first tightening bolt (2E), combine three sets, then place the first tightening bolts (2E) of each set at the through holes on the rib plate (2C) of the first-stage joint unit. After placing, adjust the 3 first tightening bolts (2E) in the reverse direction so that the 6 connecting columns (2A) of the first joint unit correspond one by one to the 6 through holes of the first right-side joint unit (2D) and the first left-side joint unit (2B), and then weld them together; splice two docking joints on the rib plate (2C) of the first-stage joint unit of the combined docking joint to complete the assembly of the first-stage combined docking joint (2); complete the assembly of the second-stage combined docking joint (4) and the third-stage combined docking joint (6) in the same steps; c) Install the blade integral body including the airbag: Fill the airbag (8) with inert gas helium, place the airbag (8) in the rib plate gaps between the segmented blade A section and the segmented blade B section, bury the pipeline into the through holes of each rib plate and connect it to the airbag (8), and then paste the A section and B section of each blade on site, and use the female mold of the blade shape to complete the final aerodynamic shape forming of the blade; d) In step a), use the prefabricated first-stage combined docking joint (2), second-stage combined docking joint (4) and third-stage combined docking joint (6) to paste on site at the docking positions corresponding to the first-stage segmented blade (1), second-stage segmented blade (3), third-stage segmented blade (5) and fourth-stage segmented blade (7). Use a mold positioned by threaded steel to position the hole diameter on each side of the docking joint, and then bury both sides of the docking joint into the corresponding blade through holes; e) In step b), insert a hex wrench through the through hole on the rib plate (2C) of the first-stage joint unit to the hex nut of the first tightening bolt (2E) and rotate to bend the six connecting columns (2A) of the first joint unit inward, so that the first left-side joint unit (2B) and the first right-side joint unit (2D) are bent and deformed by the tensile force of the six connecting columns (2A) of the first joint unit, and are stuck at the central through hole of the segmented blade, so that the first-stage combined docking joint (2) connects the first-stage segmented blade (1) and the second-stage segmented blade (3). Complete the connection of the second-stage combined docking joint (4) between the second-stage segmented blade (3) and the third-stage segmented blade (5) in the same steps; the third-stage combined docking joint (6) connects the third-stage segmented blade (5) and the fourth-stage segmented blade (7).

10. The connection method of a super-large wind turbine segmented blade according to claim 9, characterized in that, The following maintenance steps are included: a) Insert a hex wrench through the through-hole on the rib plate (2C) of the first-stage joint unit into the hex nut of the first tightening bolt (2E) and rotate it to straighten the six first joint unit connecting columns (2A) from the bent state, so that the first right joint unit (2D) and the first left joint unit (2B) are straightened by the thrust of the six first joint unit connecting columns (2A) from the bent deformation state, and separate the first-stage segmented blade (1) and the second-stage segmented blade (3) from the first-stage combined docking joint (2) stuck at the central through-hole of the segmented blade. Complete the separation of the second-stage segmented blade (3) and the third-stage segmented blade (5) by the second-stage combined docking joint (4) in the same steps; separate the third-stage segmented blade (5) and the fourth-stage segmented blade (7) by the third-stage combined docking joint (6) to complete the subsequent maintenance of the first-stage combined docking joint (2), the second-stage combined docking joint (4) and the third-stage combined docking joint (6). b) The rib plate (3A2) at the docking part of the segmented blade and the joint unit is provided with a through-hole (3A1). Connect the air injection device to the pipeline through the through-hole (3A1), bury the pipeline into the through-holes (3A1) of each rib plate and connect it to the airbag (8), and inflate the airbag (8) through the pipeline by the air injection device for maintenance.

Images