Wind-resistant reinforcing device for tower drum of wind driven generator

Abstract

The utility model relates to the field of wind driven generator tower drum reinforcement, and particularly discloses a wind-resistant reinforcement device of a wind driven generator tower drum, which comprises a first reinforcement shell and a second reinforcement shell which are arranged on the outer ring of the tower drum, and the first reinforcement shell and the second reinforcement shell are connected together through a connecting piece to form a tower drum reinforcement shell; a first connecting lug and a second connecting lug are fixed to the outer ring of the first reinforcing shell and the outer ring of the second reinforcing shell, and the first connecting lug is connected with a first foundation bolt through a long steel strand. The second connecting lug is connected with one end of the secondary long steel strand, the other end of the secondary long steel strand is connected with one end of the damper, the other end of the damper is connected with one end of the short steel strand, and the other end of the short steel strand is connected with the second foundation bolt.

Description

A wind-resistant reinforcement device for wind turbine towers Technical Field

[0001] This utility model relates to a wind-resistant reinforcement device for wind turbine towers and its application method, belonging to the field of engineering structure reinforcement. Background Technology

[0002] Wind turbines are crucial equipment for converting wind power into electricity, consisting of a generator head, tower, and foundation. However, strong winds and even typhoons frequently occur in some areas during the summer, causing serious casualties and economic losses; therefore, it is necessary to reinforce wind turbines.

[0003] Currently, there are three common reinforcement methods: the first method is to reinforce the foundation base of the wind turbine; the second method is to reinforce the wind turbine head; and the third method is to reinforce the tower of the wind power generation system.

[0004] The first reinforcement method has two main problems: First, while it can be used to reinforce the foundation before the wind turbine tower and generator head are installed, it becomes a large-scale and costly undertaking once the entire wind turbine system is installed and ready to withstand typhoons. Second, it is difficult to prevent the wind turbine tower from experiencing a three-stage failure under extreme wind conditions, leading to the reinforced generator head falling and breaking. Therefore, wind-resistant reinforcement of the wind turbine tower to ensure its stability and reliability during strong winds or typhoons is the prerequisite and foundation for ensuring the safe operation of the entire wind turbine system.

[0005] Currently, some reinforcement devices for strengthening towers are disclosed in existing patents, such as patents CN202210960585.6, CN 201620647765.9, and CN 201920120502.6. However, some of these reinforcement devices are too simple, relying solely on steel strands for reinforcement, which results in severe wind-induced vibration of the steel strands. Other reinforcement devices are designed to address wind-induced vibration of the steel strands in an overly complex manner, leading to high reinforcement costs. Summary of the Invention

[0006] The purpose of this invention is to solve the problems existing in the tower reinforcement device in the prior art, and to provide a new wind-resistant reinforcement device for wind turbine towers. The reinforcement device has a relatively simple structure and a good reinforcement effect.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0008] A wind-resistant reinforcement device for a wind turbine tower includes a first reinforcement shell and a second reinforcement shell disposed on the outer ring of the tower. The first reinforcement shell and the second reinforcement shell are connected together by a connector to form a tower reinforcement shell. A first connecting lug and a second connecting lug are fixed on the outer ring of the first reinforcement shell and the second reinforcement shell. The first connecting lug is connected to a first anchor bolt via a long steel strand. The second connecting lug is connected to one end of a secondary long steel strand, the other end of which is connected to one end of a damper. The other end of the damper is connected to one end of a short steel strand, and the other end of the short steel strand is connected to a second anchor bolt.

[0009] As a further technical solution, the long steel strands are arranged in pairs around the outer ring of the tower; the two pairs of long steel strands are symmetrically arranged with respect to the axial center plane of the tower.

[0010] As a further technical solution, one end of the long steel strand is connected to the first connecting ear through a set of spring buckles and compression anchors, and the other end is connected to the first anchor bolt through another set of spring buckles and compression anchors.

[0011] As a further technical solution, two of the reinforcement components consisting of the secondary long steel strand, the damper, and the short steel strand are arranged on the outer ring of the tower, and the two reinforcement components are symmetrically arranged with respect to the axial center plane of the tower.

[0012] As a further technical solution, one end of the secondary long steel strand is connected to the damper through a set of spring buckles and compression anchors, and the other end is connected to the second connecting ear through another set of spring buckles and compression anchors.

[0013] As a further technical solution, one end of the short steel strand is connected to the second anchor bolt through a set of spring clips and compression anchors, and the other end is connected to the damper through another set of spring clips and compression anchors.

[0014] As a further technical solution, both the first and second reinforcing shells are hollow semi-circular frustum structures, and the first and second reinforcing shells are connected by bolts.

[0015] As a further technical solution, the inner walls of the first and second reinforcing shells are provided with rubber pads, and the first and second reinforcing shells are made of stainless steel.

[0016] This utility model has the following beneficial effects:

[0017] (1) The wind turbine tower wind-resistant reinforcement device of this utility model targets the problem of wind turbine towers being prone to three-stage damage under extreme wind conditions. It uses the first reinforcement shell and the second reinforcement shell to surround and reinforce the parts of the wind turbine tower that are prone to damage. At the same time, steel strands are used to further fix the wind turbine tower and bear part of the wind load, reducing the wind resistance pressure on the wind turbine tower. In addition, the secondary long steel strands and short steel strands are used in conjunction with the damper to dissipate most of the energy generated by the wind load, avoiding the swaying of the wind turbine tower in the wind and the wind-induced vibration of the steel strands. This improves the stability and reliability of the wind turbine tower when extreme wind conditions occur, and ensures the safe operation of the entire wind turbine equipment.

[0018] (2) The wind turbine tower wind-resistant reinforcement device of this utility model is aimed at the wind turbines located in coastal areas that are subject to more severe corrosion, resulting in rust, cross-sectional weakening and strength reduction. It uses a first and second reinforced shell made of stainless steel to enclose the wind turbine tower for local protection. At the same time, rubber pads are embedded in the first and second reinforced shells and they are connected by fixing bolts. This not only ensures that the first and second reinforced shells are tightly fitted to the wind turbine tower, but also effectively prevents the surface of the wind turbine tower from directly contacting the humid air and corrosive media, avoiding more severe corrosion, improving the wind turbine's corrosion resistance, extending its service life and reducing operation and maintenance costs.

[0019] (3) In the wind turbine tower wind-resistant reinforcement device of this utility model, the first reinforcement shell and the second reinforcement shell are connected by fixing bolts, and the connecting lugs are connected to the first reinforcement shell and the second reinforcement shell by welding. The steel strands are connected to the connecting lugs, dampers and ground anchor bolts by spring buckles and compression anchors. The above connection processes are all conventional construction processes, the construction process is simple, and the connection is safe and reliable. In addition, the device is easy to install and disassemble, can be reused, and the damaged parts are easy to replace, making it economical and applicable. Attached Figure Description

[0020] Figure 1(a) and Figure 1(b) are schematic diagrams of the wind-resistant reinforcement device for wind turbine towers disclosed in this utility model before the first reinforcement shell and the second reinforcement shell are connected.

[0021] Figures 2(a) and 2(b) are exploded views of the first reinforcing shell in the wind-resistant reinforcement device for wind turbine towers disclosed in this utility model.

[0022] Figures 3(a) and 3(b) are schematic diagrams of the connection between the first and second reinforced shells; where Figure 3(a) is a top view and Figure 3(b) is a bottom view.

[0023] Figure 4 is a schematic diagram of the connection between the end of the steel strand and the spring clip.

[0024] Figure 5 is a partial enlarged view of the connection between the end of the steel strand and the spring clip.

[0025] Figure 6 is a schematic diagram of anchor bolts.

[0026] Figure 7 is a schematic diagram of the shape of a wind turbine blade.

[0027] Figure 8 is a schematic diagram of the wind-resistant reinforcement device for the wind turbine tower being installed on the wind turbine tower.

[0028] Figure 9 is a schematic diagram of the position of the wind load F on the wind turbine tower.

[0029] Figure 10 is a force analysis diagram of the connection lug on the center line of the outer side of the shell.

[0030] Figure 11 is a force analysis diagram at the anchor bolts.

[0031] In the diagram: 1-First reinforcing shell, 2-Second reinforcing shell, 31-Connecting ear, 32-Connecting ear, 33-Connecting ear, 34-Connecting ear, 35-Connecting ear, 36-Connecting ear, 37-Connecting ear, 38-Connecting ear, 39-Connecting ear, 310-Connecting ear, 311-Connecting ear, 312-Connecting ear, 41-Connecting hole, 42-Connecting hole, 43-Connecting hole, 44-Connecting hole, 45-Connecting hole, 46-Connecting hole, 47-Connecting hole, 48-Connecting hole, 49-Connecting hole, 410-Connecting hole, 411-Connecting hole, 412-Connecting hole, 51-Fixing bolt, 52-Fixing bolt, 53-Fixing bolt, 54 - Fixing bolt, 61- Fixing nut, 62- Fixing nut, 63- Fixing nut, 64- Fixing nut, 71- Rubber pad, 72- Rubber pad, 8- Damper, 9- Spring buckle, 10- Extrusion anchor, 111- Anchor bolt, 112- Anchor bolt, 113- Anchor bolt, 114- Anchor bolt, 121- Long steel strand, 122- Long steel strand, 123- Long steel strand, 124- Long steel strand, 131- Secondary long steel strand, 132- Secondary long steel strand, 133- Secondary long steel strand, 134- Secondary long steel strand, 141- Short steel strand, 142- Short steel strand, 143- Short steel strand, 144- Short steel strand. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the present utility model. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the present utility model.

[0033] The following description, in conjunction with Figures 1(a), 1(b), 2(a), 2(b), 3(a), 3(b), 4, 5, 6, 7, and 8, illustrates this embodiment. This embodiment describes a wind-resistant reinforcement device for a wind turbine tower, comprising a first reinforcement shell 1, a second reinforcement shell 2, four fixing bolts, four fixing nuts corresponding to the four fixing bolts, twelve steel strands, a damper, twenty-four spring clips, two rubber pads, and four anchor bolts.

[0034] The first reinforced shell 1 and the second reinforced shell 2 each have a connecting lug 31, a connecting lug 32, a connecting lug 33, a connecting lug 34, a connecting lug 35, a connecting lug 36, a connecting lug 37, and a connecting lug 38 welded to their four outer corners. Each of the eight connecting lugs has a connecting hole 41, a connecting hole 42, a connecting hole 43, a connecting hole 44, a connecting hole 45, a connecting hole 46, a connecting hole 47, and a connecting hole 48 symmetrically welded to the center of the outer busbar of the first reinforced shell 1 and the second reinforced shell 2. Each connecting lug is perpendicular to the outer surface of the shell and has a round hole 49, a round hole 410, a round hole 411, and a round hole 412 symmetrically welded to its center. The first reinforced shell 1 and the second reinforced shell 2 have the same shape and are each lined with a rubber pad 7. They are connected to form a closed hollow frustum structure by fixing bolts 5 and fixing nuts 6.

[0035] The wind-resistant reinforcement device for the wind turbine tower of this embodiment includes twelve steel strands, comprising four long steel strands (long steel strand 121, long steel strand 122, long steel strand 123, long steel strand 124), four medium-length steel strands (medium-length steel strand 131, medium-length steel strand 132, medium-length steel strand 133, medium-length steel strand 134), and four short steel strands (short steel strand 141, short steel strand 142, short steel strand 143, short steel strand 144). The long steel strands are arranged in pairs around the outer ring of the tower. The two pairs of long steel strands are symmetrically arranged with respect to the axial center plane of the tower. One end of each long steel strand is connected to a corresponding connecting lug through a set of spring buckles 9 and compression anchors 10, and the other end is connected to a corresponding anchor bolt through another set of spring buckles 9 and compression anchors 10. Furthermore, two reinforcement components consisting of the secondary long steel strand, damper 8, and short steel strand are installed on the outer ring of the tower, symmetrically arranged with respect to the axial center plane of the tower. One end of the secondary long steel strand is connected to the damper 8 via a set of spring clips 9 and compression anchors 10, and the other end is connected to the corresponding connecting lug via another set of spring clips and compression anchors. One end of the short steel strand is connected to the corresponding anchor bolt via a set of spring clips 9 and compression anchors 10, and the other end is connected to the damper 8 via another set of spring clips 9 and compression anchors 10.

[0036] The wind-resistant reinforcement device for the wind turbine tower in this embodiment has a first reinforcement shell 1 and a second reinforcement shell 2, both of which are hollow semi-circular frustum structures. The first reinforcement shell 1 and the second reinforcement shell 2 are made of 304 stainless steel and have a wall thickness of 12mm. The length of the busbar on the side of the first reinforcement shell 1 and the second reinforcement shell 2 is 1.5m.

[0037] Furthermore, in this embodiment of the wind turbine tower wind-resistant reinforcement device, the connecting ear 3 is made of 304 stainless steel, the side length of the connecting ear 3 is 55mm, the thickness of the connecting ear 3 is 15mm, and the diameter of the central circular hole 4 of the connecting ear 3 is 18mm.

[0038] Furthermore, in this embodiment, the wind-resistant reinforcement device for the wind turbine tower uses M16 hexagonal bolts for fixing bolt 5.

[0039] Furthermore, for the wind-resistant reinforcement device of the wind turbine tower, the fixing nut 6 is an M16 external hexagonal nut.

[0040] Furthermore, in the wind-resistant reinforcement device for the wind turbine tower of this embodiment, the rubber pad 7 is made of ethylene propylene rubber and the rubber pad thickness is 15mm.

[0041] Furthermore, in this embodiment, the two reinforced outer shells of the wind-resistant reinforcement device are connected by bolts, facilitating rotation and adjustment around the wind turbine tower. Simultaneously, the steel strands are connected to the outer shells and anchor bolts via spring clips and compression anchors, making connection and disassembly convenient. Based on the predicted wind direction, the orientation of the wind-resistant reinforcement device is adjusted in advance, ensuring that the two sets of secondary long steel strands with dampers, the dampers, and the short steel strand devices are positioned optimally, allowing the dampers to function effectively. Therefore, when the wind turbine is affected by strong winds of different directions, two sets of dampers symmetrically arranged around the tower axis are sufficient to protect the wind turbine tower. In addition, considering cost, since dampers are expensive, installing four dampers in the wind-resistant reinforcement device would be costly. Therefore, in this embodiment, only two dampers are used.

[0042] The construction method for the wind-resistant reinforcement device for the wind turbine tower mentioned above includes the following steps:

[0043] Step 1: Based on the installation positions of the first reinforcing shell 1 and the second reinforcing shell 2 on the wind turbine tower, determine the inner diameters of the upper and lower bottom surfaces of the hollow frustum-shaped structure formed by the first reinforcing shell 1 and the second reinforcing shell 2 after they are joined together;

[0044] Step 2: Weld a connecting lug 31, a connecting lug 32, a connecting lug 33, a connecting lug 34, a connecting lug 35, a connecting lug 36, a connecting lug 37, and a connecting lug 38 perpendicular to the outer surface of the outer shell to the four corners of the outer side of the first reinforced shell 1 and the second reinforced shell 2, respectively; and drill a round hole 41, a round hole 42, a round hole 43, a round hole 44, a round hole 45, a round hole 46, a round hole 47, and a round hole 48 in the center of each connecting lug;

[0045] Step 3: Symmetrically weld connecting ears 39, 310, 311, and 312 at the center of the outer busbars of the first reinforced shell 1 and the second reinforced shell 2 respectively. Each connecting ear is perpendicular to the outer side of the shell and has a round hole 49, 410, 411, or 412 drilled in its center.

[0046] Step 4: Attach the two rubber pads 71 ​​and 72 to the inner walls of the first reinforced shell 1 and the second reinforced shell 2, respectively. The rubber pads are soft and elastic; attaching them to the inner walls of the shells allows for better contact between the wind-resistant reinforcement device and the wind turbine tower, enhancing the contact strength. Ethylene propylene rubber itself has good water resistance and acid and alkali resistance. Wrapped in these rubber pads, the wind turbine tower avoids direct contact with moisture in the air. Furthermore, wind turbines located in coastal areas are susceptible to acid and alkali corrosion; these ethylene propylene rubber pads can protect parts of the wind turbine tower from moisture and acid / alkali erosion.

[0047] Step 5: Install spring clips 9 at both ends of each of the twelve steel strands;

[0048] Step 6: Set up four fixing points on the ground with the wind turbine foundation base as the center and radius R. The included angle between the centers of each two adjacent fixing points is 90°. Set up one anchor bolt at each fixing point, for a total of four anchor bolts, namely anchor bolt 111, anchor bolt 112, anchor bolt 113, and anchor bolt 114.

[0049] In step one above, let the outer diameter of the bottom section of the wind turbine tower be *a*, the outer diameter of the top section be *b*, the height of the tower be *h*, and the angle between the side of the tower and the vertical direction be *[a]*. If the length of the side generatrix of the first reinforced shell 1 and the second reinforced shell 2 is h0, then the height of the upper edge of the first reinforced shell 1 and the second reinforced shell 2 from the bottom surface of the tower is h1. The height of the lower edge of the first reinforcing shell 1 and the second reinforcing shell 2 from the bottom surface of the tower is h2. The inner diameter of the bottom surface of the closed hollow frustum-shaped structure formed by the first reinforcing shell 1 and the second reinforcing shell 2 is r1. The inner diameter of the bottom surface of the closed hollow frustum-shaped structure formed by the first reinforcing shell 1 and the second reinforcing shell 2 is r2. ;

[0050] In step two, the weld is an equilateral fillet weld with a weld height of 8mm;

[0051] In step three, two connecting lugs 39, 310, 311, and 312 are symmetrically welded at the center positions of the outer busbars of the first reinforced shell 1 and the second reinforced shell 2, respectively. The welds are equilateral fillet welds with a height of 8 mm. The four connecting lugs 39, 310, 311, and 312 are perpendicular to the outer surface of the shell, and the centers of the contact surfaces between the four connecting lugs 39, 310, 311, and 312 and the shell are located at the trisection points of the centerline of the outer surface of the shell. The height of the center position of the outer busbar of the shell from the bottom surface of the tower is h3.

[0052] In step four, the adhesive used to attach the rubber pad 7 is a modified epoxy resin adhesive, and the surface area of ​​both sides of the rubber pad is the same as the surface area of ​​the inner wall of the first reinforcing shell 1 and the second reinforcing shell 2.

[0053] In step five, among the twelve steel strands, there are four long steel strands of equal length: 121, 122, 123, and 124; four second-long steel strands of equal length: 131, 132, 133, and 134; and four short steel strands of equal length: 141, 142, 143, and 144. The length of the long steel strand 12 is L0. The lengths of the second longest steel strand 13 and the shortest steel strand 14 are 75%-80% and 20%-25% of the length of the long steel strand 12, respectively. All steel strands are selected from 1×7-12.7 type 1860 grade low relaxation prestressed steel strands.

[0054] The spring buckle is an M20 type safety rope lock. Spring buckles 9 are installed at both ends of twelve steel strands. The connection between the steel strands and spring buckles 9 is as follows: a cylindrical channel is drilled through the bottom of each spring buckle 9, with the diameter of the upper and lower bottom surfaces of this channel equal to the diameter of the selected steel strand cross-section. The steel strands pass through the spring buckles 9, and a compression anchor 10 is installed at the end of the steel strand exiting the spring buckles 9. The compression anchor 10 connects the compression anchor 10 to the steel strand as a whole. When the steel strand is under tension, the compression anchor 10, which is clamped on the spring buckle 9, generates friction with the steel strand to counteract the tension.

[0055] In step six, R is An anchor bolt 11 is pre-embedded at each fixed point. The anchor bolt is an M48 type with a nominal length of 1250mm. The pre-embedding method is as follows: dig a pit at the fixed point with a length of 450mm, a width of 400mm, and a depth of 1350mm. Insert the anchor bolt 11 vertically into the center of the pit, with the top of the anchor bolt 11 300mm above the ground. Pour C40 concrete.

[0056] The method of using the above-mentioned wind turbine tower wind-resistant reinforcement device includes the following steps:

[0057] Step 1: Determine the installation positions of the first reinforcing shell 1 and the second reinforcing shell 2 on the wind turbine tower;

[0058] Step 2: The first reinforcing shell 1 and the second reinforcing shell 2 are fixed to the wind turbine tower by four fixing bolts 5 and four fixing nuts 6. After the first reinforcing shell 1 and the second reinforcing shell 2 are closed, they form a closed hollow frustum structure.

[0059] Step 3: Connect the damper 8 to the secondary long steel strand 13 and the short steel strand 14;

[0060] Step 4: Connect the long steel strand 12 to the first reinforcing shell 1, the second reinforcing shell 2, and the anchor bolts 11 at the fixing points;

[0061] Step 5: Connect the secondary long steel strand 13, damper 8, and short steel strand 14 formed in Step 3 to the first reinforcing shell 1, the second reinforcing shell 2, and the anchor bolts 11 at the fixing point.

[0062] This embodiment describes a method for using a wind-resistant reinforcement device for a wind turbine tower. In step one, the first reinforcement shell 1 and the second reinforcement shell 2 are located at the same height on the wind turbine tower, and the lower edge of the first reinforcement shell 1 and the second reinforcement shell 2 is at a height from the bottom of the wind turbine tower. ;

[0063] In step two, the fixing bolts 5 at the same height are installed in opposite directions. Flat washers and spring washers are placed between the fixing bolts 5 and the fixing nuts 6 to ensure the fixing bolts are tightened and do not loosen. M20 type round flat washers and M20 type spring washers are used. The relative positions of the components are: fixing bolt head 5 - connecting lug 3 on the first reinforcing shell 1 or the second reinforcing shell 2 - connecting lug 3 on the second reinforcing shell 2 or the first reinforcing shell 1 - flat washer - spring washer - fixing nut 6. This wind-resistant reinforcement device is connected by bolts and fixed with nuts, a connection and fixing method that facilitates installation and disassembly. During the dry season, the wind-resistant reinforcement device can be disassembled and stored to avoid long-term exposure to chronic corrosion from air, water vapor, acid and alkali components, etc. During the monsoon season, the wind-resistant reinforcement device can be reinstalled on the wind turbine tower for reinforcement and protection. The disassembly and installation process of this wind-resistant reinforcement device requires minimal labor, and disassembly and storage also allow for repeated use of the device, making it economical and environmentally friendly.

[0064] In step three, there are two dampers 8. The damper 8 model is a viscous damper VFD-300. The connection method between the damper 8 and the steel strand is as follows: the spring buckle 9 at one end of the two secondary long steel strands 13 is fastened into one end of the damper 8, and the spring buckle 9 at one end of the two short steel strands 14 is fastened into the other end of the same damper 8. That is, each damper 8 is connected to two secondary long steel strands 13 and two short steel strands 14 at both ends respectively.

[0065] In step four, the four long steel strands 12 are divided into two groups of two. In the first group, the spring clips 9 at one end of the two long steel strands 121 and 122 are fastened into a connecting lug 39 in the middle of the first reinforcing shell 1, and the spring clips 9 at the other end of the two long steel strands 121 and 122 are fastened into the anchor bolt 111 at the fixing point. In the second group, the spring clips 9 at one end of the two long steel strands 123 and 124 are fastened into a connecting lug 311 in the middle of the second reinforcing shell 2, and the spring clips 9 at the other end of the two long steel strands 123 and 124 are fastened into the anchor bolt 113 at the fixing point. The two long steel strands 121 and 122 in the first group and the two long steel strands 123 and 124 in the second group are arranged symmetrically about the wind turbine tower. The angle between the steel strands and the wind turbine tower is... ;

[0066] In step five, the two sets of secondary long steel strand 13-damper 8-short steel strand 14 devices formed in step three are divided into two groups. In the first group, the spring clips 9 at the ends of the secondary long steel strands 131 and 132 not connected to the damper 8 are fastened into another connecting lug 310 in the middle of the first reinforcing shell 1. The spring clips 9 at the ends of the first group of short steel strands 141 and 142 not connected to the damper 8 are fastened into the anchor bolts 114 at the fixing points. The second group of secondary long steel strands 133... The spring clip 9 at the end of the second-long steel strand 134 not connected to the damper 8 is fastened into another connecting lug 312 in the middle of the second reinforcing shell 2. The spring clips 9 at the ends of the second set of short steel strands 143 and 144 not connected to the damper 8 are fastened into the anchor bolts 112 at the fixing point. The first set of second-long steel strand 13-damper 8-short steel strand 14 devices and the second set of second-long steel strand 13-damper 8-short steel strand 14 devices are arranged symmetrically with the wind turbine tower as the axis. The angle between the steel strands and the wind turbine tower is... The damper works in conjunction with the steel strands to bear the wind load. The presence of the damper can reduce the wind vibration of the wind turbine tower and also reduce the fatigue damage of the steel strands, thereby improving the wind resistance of the wind turbine tower.

[0067] The wind resistance verification process of the wind turbine tower wind-resistant reinforcement device based on the above specific implementation method is as follows:

[0068] The shape of the wind turbine blade is shown in Figure 7. The area of ​​the wind turbine blade is calculated using the following formula:

[0069] (1)

[0070] (2)

[0071] The shape of the wind turbine tower is shown in Figure 8. The area of ​​the wind turbine tower is calculated using the following formula:

[0072] (3)

[0073] The total wind-receiving area of ​​the wind turbine is:

[0074] (4)

[0075] The wind load on a wind turbine is calculated using the following formula:

[0076] (5)

[0077] In the formula, Wind load on wind turbine (unit: );

[0078] Total wind-receiving area of ​​the wind turbine (unit: );

[0079] For wind pressure, , Wind speed (unit: m / s);

[0080] Since the drag coefficient is dimensionless, the wind turbine tower is approximated as a cylinder. Take 1.2.

[0081] Specifically, affected by Typhoon "Mangkut" (wind speed...) ) impact and damage Mulan Bay Wind Farm Taking a wind turbine as an example, the wind turbine model is NREL 5 MW, the tower height h is 90m, and the angle between the side of the tower and the vertical direction is... The angle is 0.6°, the blade length e is 60m, the blade tail width c is 5m, the outer diameter a of the bottom section of the tower is 6m, the outer diameter b of the top section of the tower is 4m, the tower material is Q345 steel, and the bottom wall thickness d is 30mm. Therefore, according to formulas (1) to (5), the wind load on the wind turbine is:

[0082]

[0083] The length h0 of the side generatrix of the first and second reinforcing shells of the wind-resistant reinforcement device is 1.5m. Therefore, the height of the upper edge of the first and second reinforcing shells from the bottom of the tower is... The height of the lower edge of the first and second reinforcing shells from the bottom of the tower. Wind load The location of the wind load on the wind turbine is shown in Figure 9. The height of the wind load application point from the bottom of the tower is [missing information]. , The bending moment at the bottom of the wind turbine tower is:

[0084]

[0085] The bending bearing capacity at the base of the wind turbine tower is calculated using the following formula:

[0086] (6)

[0087] In the formula, Bending capacity at the base of the wind turbine tower (unit: );

[0088] The section modulus of the bottom section of the wind turbine tower (unit: ), ;

[0089] Design value of tensile strength of wind turbine tower (unit: The tower is made of Q345 steel, therefore .

[0090] According to formula (6), the bending bearing capacity at the bottom of the wind turbine tower is:

[0091]

[0092] because Therefore, the wind-resistant reinforcement device needs to bear a portion of the wind load to ensure the safety of the wind turbine tower. Thus, it is necessary to verify whether the tensile strength of the steel strands, the weld strength of the connecting lugs, and the pull-out strength of the anchor bolts in the wind-resistant reinforcement device meet the requirements.

[0093] (1) Calculation of tensile strength of steel strand:

[0094] The remaining bending moment that the wind-resistant reinforcement device needs to withstand is:

[0095]

[0096] The remaining horizontal tensile force that the steel strands of the wind-resistant reinforcement device need to withstand is:

[0097]

[0098] The installation method of the steel strand is shown in Figure 8. The angle between each set of steel strands (consisting of two strands) and the wind turbine tower is... , ,Right now =37°

[0099] As shown in Figure 10, each group of steel strands consists of two strands, and the horizontal component of the tensile bearing capacity of each group of steel strands is:

[0100]

[0101] In the formula, Tensile strength provided for a single steel strand (unit: ), ;

[0102] This refers to the nominal diameter of a single steel strand. The steel strand used is a 1×7-12.7 type 1860 grade low-relaxation prestressed steel strand. ;

[0103] This is the calculated tensile strength value for a single steel strand. The steel strand used is a 1×7-12.7 type 1860 grade low-relaxation prestressed steel strand. .

[0104] because That is, the tensile strength of a set of steel strands is greater than the tensile force it needs to bear, so the tensile strength verification of the steel strands meets the requirements.

[0105] (2) Strength verification of connecting lug weld

[0106] Figure 10 shows the stress condition of the connecting lugs on the outer side of the wind-resistant reinforcement device. The connecting lugs are 55mm long and 15mm thick. The weld length on one side is 55mm, and the weld height is... If the length is 8mm, then the effective length of the double-sided weld is... The welding rod used is E50 type, and the design strength value for the fillet weld is... .

[0107] The tension of the steel strand is:

[0108]

[0109] Horizontal component of tension in steel strand and vertical components They are respectively:

[0110]

[0111]

[0112] The normal stress borne by the connecting lug weld is:

[0113]

[0114] The shear stress borne by the connecting lug weld is:

[0115]

[0116]

[0117] Therefore, the strength of the connecting lug weld meets the requirements.

[0118] (3) Calculation of pull-out strength of anchor bolts

[0119] The stress condition of the anchor bolts is shown in Figure 11. The anchor bolt type is M48, and the diameter of the anchor bolt shank is... The anchor bolt is 48mm thick and made of Q345 carbon steel with a tensile strength design value of [value missing]. 265 N / mm 2 The nominal length of the anchor bolt is 1250mm, the top of the anchor bolt protrudes 300mm above the ground, and the embedment depth is... The diameter is 950mm, and the concrete pouring grade is C40.

[0120] The vertical tensile force generated by the steel strand on the anchor bolts for:

[0121]

[0122] The maximum tensile force that anchor bolts can withstand is:

[0123]

[0124] because Therefore, the anchor bolts will not fail under tension.

[0125] The bond strength between the anchor bolts and the concrete is calculated using the following formula:

[0126] (7)

[0127] In the formula, Bond strength between anchor bolts and concrete (unit: );

[0128] d2 is the diameter of the anchor bolt shank (unit: mm);

[0129] Anchor bolt embedment depth (unit: mm);

[0130] Design value of tensile strength of concrete (unit: The concrete grade is C40, therefore .

[0131] because That is, the bond strength between the anchor bolt and the concrete is greater than the vertical tension of the steel strand on the anchor bolt, so the anchor bolt will not be pulled out.

[0132] Based on the above calculations, the strength of the three important load-bearing components in the wind-resistant reinforcement device, namely the steel strand, connecting lugs, and anchor bolts, all meet the requirements. This improves the stability and reliability of the wind turbine tower during strong winds or typhoons, ensures the safe operation of the entire wind turbine equipment, and reduces economic losses.

[0133] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, this utility model will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by this utility model.

[0134] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A wind-resistant reinforcement device for a wind turbine tower, characterized in that, The system includes a first reinforcing shell and a second reinforcing shell disposed on the outer ring of the tower. The first and second reinforcing shells are connected together by connectors to form the tower reinforcement shell. A first connecting lug and a second connecting lug are fixed on the outer ring of the first and second reinforcing shells. The first connecting lug is connected to a first anchor bolt via a long steel strand. The second connecting lug is connected to one end of a secondary long steel strand, the other end of which is connected to one end of a damper. The other end of the damper is connected to one end of a short steel strand, and the other end of the short steel strand is connected to a second anchor bolt.

2. Wind reinforcement device for a wind turbine tower according to claim 1, characterized in that The long steel strands are arranged in pairs around the outer ring of the tower; the two pairs of long steel strands are symmetrically arranged with respect to the axial center plane of the tower.

3. The wind-resistant reinforcement device for wind turbine towers as described in claim 2, characterized in that, One end of the long steel strand is connected to the first connecting ear via a set of spring clips and compression anchors, and the other end is connected to the first anchor bolt via another set of spring clips and compression anchors.

4. The wind-resistant reinforcement device for wind turbine towers as described in claim 1, characterized in that, Two reinforcement components consisting of the secondary long steel strand, damper, and short steel strand are installed on the outer ring of the tower, and the two reinforcement components are symmetrically arranged with respect to the axial center plane of the tower.

5. Wind reinforcement means for a wind turbine tower according to claim 4, characterized in that One end of the secondary long steel strand is connected to the damper via a set of spring clips and compression anchors, and the other end is connected to the second connecting lug via another set of spring clips and compression anchors.

6. A wind reinforcement device for a wind turbine tower according to claim 4, characterized in that One end of the short steel strand is connected to the second anchor bolt via a set of spring clips and compression anchors, and the other end is connected to the damper via another set of spring clips and compression anchors.

7. The wind-resistant reinforcement device for wind turbine towers as described in claim 4, characterized in that, The reinforcing components are spaced apart from the long steel strands.

8. The wind-resistant reinforcement device for wind turbine towers as described in claim 1, characterized in that, Both the first and second reinforcing shells are hollow semi-circular frustum structures, and the first and second reinforcing shells are connected by bolts.

9. The wind-resistant reinforcement device for wind turbine towers as described in claim 1, characterized in that, The inner walls of the first and second reinforcing shells are provided with rubber pads.

10. The wind-resistant reinforcement device for wind turbine towers as described in claim 1, characterized in that, The first and second reinforced shells are made of stainless steel.

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