A dynamic strain response measurement device for adsorption-type wind turbine tower

Abstract

The present invention discloses a dynamic strain response measurement device for an adsorption-type wind turbine tower, which relates to the field of wind power generation technology, and includes an equipment fixing module, a positioning protection module, and a measurement and monitoring module. The measurement and monitoring module is arranged on the equipment fixing module, and the outside of the equipment fixing module is connected to the positioning protection module. The positioning protection module determines the position of the equipment fixing module and protects the equipment fixing module. The measurement and monitoring module monitors the deformation response at different positions of the wind turbine tower. The present invention adopts the above-mentioned dynamic strain response measurement device for an adsorption-type wind turbine tower, which has a simple structure, is easy to install and maintain, and can be used in conjunction with multiple equipment in series. The strong rubidium magnetic adsorption material is used to enable the sensor to be firmly attached to the tower surface, without the need for physical damage such as grinding the tower surface.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation, and in particular to a dynamic strain response measuring device for an adsorption-type wind turbine tower. Background Art

[0002] With the growing demand for clean and green energy, fixed and floating wind turbines are increasingly widely used. Due to the harsh working environment, wind turbines are subjected to wind and other external loads during operation and maintenance. The tower is the main load-bearing structure of the wind turbine, and its reliability is crucial to the safe operation of the wind turbine. Once the tower is structurally damaged, the wind turbine will directly face safety risks such as overall collapse, which will cause huge economic losses. Therefore, measuring the strain response at different positions of the wind turbine tower structure is of great significance for predicting the health status of the wind turbine structure and ensuring the safe operation of the wind turbine.

[0003] At present, there is little research in the engineering and academic circles at home and abroad on the dynamic strain response monitoring of wind turbine tower structures under actual operation and maintenance conditions. In 2016, a patent (CN201620711115.6) used fiber Bragg grating strain gauges to monitor the stress and strain of large-diameter steel pipe piles. During the test, the sensors were installed by grinding steel piles and welding. In 2018, a paper (Reliability analysis of off-shore damage extrapolations of wind turbines using offshore strain measurements, Journal of Physics: Conference Series, 1037, 032035) reported that fiber Bragg grating strain gauges were used to measure the strain response of actual offshore wind turbines. The fiber strain gauges were fixed on the wind turbine tower structure by welding to sense the strain response of the wind turbine structure, and only two measuring points were arranged. In addition, the traditional wired test method of resistance strain gauges also requires grinding and pasting to achieve dynamic response measurement at the specified position of the tower. The above-mentioned tower dynamic strain response test method has the following technical limitations: (1) Traditional resistance strain gauges and fiber Bragg grating strain measurements are difficult to implement at multiple measurement points. During the implementation process, the tower waiting for measurement points need to be polished or welded, which affects the integrity of the structure itself and makes installation difficult; (2) The signals of traditional electrical measurement methods are susceptible to electromagnetic interference, have poor noise resistance, and have a short wired transmission distance; (3) Resistance strain gauges or fiber Bragg grating strain gauges cannot be disassembled, making it difficult to adjust the measurement point position. Summary of the invention

[0004] The purpose of the present invention is to provide a dynamic strain response measuring device for an adsorption type wind turbine tower, which is small in size, easy to install, will not cause physical damage to the tower during the installation process, and has accurate and stable measurement results, so as to solve the problems of difficult installation, high technical requirements, and poor measurement accuracy of existing equipment.

[0005] To achieve the above-mentioned purpose, the present invention provides a dynamic strain response measurement device for an adsorption-type wind turbine tower, comprising an equipment fixing module, a positioning protection module and a measurement and monitoring module, wherein the measurement and monitoring module is arranged on the equipment fixing module, and the outside of the equipment fixing module is connected to the positioning protection module, the positioning protection module determines the position of the equipment fixing module and protects the equipment fixing module, and the measurement and monitoring module monitors the deformation response at different positions of the wind turbine tower.

[0006] Preferably, the equipment fixing module is composed of two magnetic suction cups, and an operating rod is provided at the front end of the two magnetic suction cups. The operating rod passes through the front panel and is connected to one end of the rotating drum. A slot is provided inside the rotating drum, and a rectangular magnet is installed in the slot. The other end of the rotating drum is connected to the rear panel through a rear bearing.

[0007] Preferably, the magnetic suction cup is configured as a cubic structure, a cylindrical cavity is opened inside the magnetic suction cup, a boss is provided on the upper part of the magnetic suction cup, linearly arranged fixed strong magnets are fixed on both sides of the boss, a top cover is provided on the upper part of the fixed strong magnet, the top cover is connected to the front panel and the rear panel by bolts, a card slot is provided on the top cover, and the card slot is connected to the measurement and monitoring module.

[0008] Preferably, the measurement and monitoring module includes an elastomer and a fiber optic Bragg grating strain gauge, the fiber optic Bragg grating strain gauge is adhered to the elastomer, both ends of the elastomer are adapted to the slot, the slot and the elastomer are connected by a bolt and a gasket, and a circular hole is opened in the middle of the gasket.

[0009] Preferably, the elastomer is a columnar structure, the diameter of the elastomer decreases from both ends to the middle, and the bending stiffness of the elastomer is smaller than the bending stiffness of the wind turbine tower.

[0010] Preferably, a plurality of the fiber Bragg grating strain gauges are provided, and the plurality of the fiber Bragg grating strain gauges are connected in series via optical fibers and connected to a demodulator, and the demodulator demodulates the strain signal to measure and monitor the strain response at different positions of the wind turbine tower in real time.

[0011] Preferably, the positioning protection module includes a positioning block and a U-shaped groove, the U-shaped groove is a rectangular structure with a handle on the upper part, the front and back sides of the U-shaped groove are provided with threaded holes, the threaded holes cooperate with positioning bolts, the positioning bolts pass through the threaded holes and are connected to the positioning block, the positioning block is arranged on the inner side of the U-shaped groove, and the end of the U-shaped groove is connected to the magnetic suction cup through a fixing bolt.

[0012] Therefore, the present invention adopts the above-mentioned dynamic strain response measurement device of the adsorption type wind turbine tower, which has the following beneficial effects:

[0013] (1) The present invention has a simple structure, is easy to maintain, and is easy to install. During installation, there is no need to grind or damage the tower, and the position of the measuring point can be easily adjusted.

[0014] (2) The present invention uses fiber Bragg grating strain gauges with high measurement accuracy and reliable results. The strain gauges can be connected in series via optical fibers, which facilitates cable layout and signal collection.

[0015] (3) The present invention uses optical fiber to transmit signals, which has a long transmission distance, strong anti-electromagnetic interference capability, and the signal is not easily contaminated by the environment.

[0016] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of a dynamic strain response measurement device for an adsorption-type wind turbine tower according to the present invention;

[0018] Figure 2 This is a schematic diagram of the installation of the elastic body structure of the present invention;

[0019] Figure 3 for Figure 2 A magnified view of structure A;

[0020] Figure 4 This is an exploded view of the internal structure of the magnetic chuck of the present invention;

[0021] Figure 5 This is a schematic diagram of the structure of the positioning protection module of the present invention;

[0022] Figure 6 This is a schematic diagram of the installation of the equipment of the present invention;

[0023] Reference numerals

[0024] 1. Equipment fixing module; 2. Positioning protection module; 3. Measurement and monitoring module; 4. Wind turbine to be tested; 11. Front panel; 12 Main structure of magnetic suction cup; 13. Rear panel; 14. Top cover; 15. Rotating drum; 16. Operating lever; 17. Front bearing; 18. Rear bearing; 19. Rectangular magnet; 110. Fixed strong magnet; 111. Bolt; 21. U-shaped groove; 22. Positioning bolt; 23. Positioning block; 24. Fixing bolt; 31. Slot; 32. Elastomer; 33. Gasket; 34. Bolt 1; 35. Optical fiber; 36. Demodulator. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0026] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0027] Example

[0028] See also Figure 1-6 The present invention provides a dynamic strain response measurement device for an adsorption-type wind turbine tower, comprising an equipment fixing module 1, a positioning protection module 2 and a measurement monitoring module 3. The measurement monitoring module 3 is arranged on the equipment fixing module 1, and the outside of the equipment fixing module 1 is connected to the positioning protection module 2. The strain measurement device of the present invention can be used in conjunction with multiple equipments, and multiple equipments can be installed along the circumferential direction at the same height of the tower. Through the coordinated work of multiple equipments, the read data is processed, so that the maximum strain response of the wind turbine tower and its corresponding angle can be obtained.

[0029] The equipment fixing module 1 is mainly composed of two magnetic suction cups. By changing the direction of the magnetic field, the equipment is controlled to be adsorbed at the position to be tested on the inner wall of the wind turbine tower. The front ends of the two magnetic suction cups are provided with operating rods 16. The operating rods 16 pass through the front panel 11 and are connected to the rotating drum 15. A front bearing 17 is provided between the rotating drum 15 and the front panel 11. The front panel 11 is provided with a groove matched with the front bearing 17. A notch is provided inside the rotating drum 15, and a rectangular magnet 19 is installed. The rectangular magnet 19 adopts a strong nepheline magnetic material. The rectangular magnet 19 rotates with the rotating drum 15. The other end of the rotating drum 15 is connected to the rear panel 13 through a rear bearing 18. The rotating drum 15 cooperates with the front and rear panels of the magnetic suction cups through the bearing and is connected to the operating rod 16, so that it can rotate around the axis of the rotating drum 15.

[0030] The main structure 12 of the magnetic suction cup is set as a cubic structure. A cylindrical cavity is opened inside the main structure 12 of the magnetic suction cup for installing and fixing the rotating drum 15. A boss is set on the upper part of the magnetic suction cup. Linearly arranged fixed strong magnets 110 are fixed on both sides of the boss. A top cover 14 is set on the upper part of the fixed strong magnet 110. The top cover 14 is connected to the front panel 11 and the rear panel 13 by bolts 111. The front and rear panels are also connected and fixed to the main structure 12 of the magnetic suction cup by bolts 111 to form a closed structure to ensure the stability and safety of the device. A card slot 31 is set on the top cover 14, and the card slot 31 is connected to the measurement and monitoring module 3. The rotating drum 15 is rotated by the operating rod 16 to control the rotation of the rectangular magnet 19 inside the rotating drum 15, thereby changing the distribution of magnetic flux lines, controlling the generation of magnetic force, and ensuring that the equipment can be adsorbed on the inner wall of the tower. When the magnetic suction cup is closed, the magnetic flux lines form a closed path inside the suction cup, that is, the magnetic field cannot leak to the outside, and the suction cup is kept in a non-adsorbed state. When the suction cup is opened, the rectangular magnet 19 inside the rotating drum 15 is arranged in the same direction as the magnet fixed in the suction cup body, and the magnetic field extends to the outside, and the equipment is adsorbed and fixed.

[0031] The measurement and monitoring module 3 includes an elastic body 32 and a fiber Bragg grating strain gauge. The fiber Bragg grating strain gauge is pasted on the elastic body 32. Both ends of the elastic body 32 are placed in the slots 31 at the rear of the two magnetic suction cups and are rigidly connected to them through a gasket 33 and a bolt 34. The elastic body 32 is a columnar structure that is slightly thicker at both ends and slightly narrower in the middle, and its bending stiffness is much smaller than that of the wind turbine tower. The gasket 33 is a square metal sheet with a round hole in the middle, which is installed between the elastic body 32 and the bolt 34 to prevent the elastic body 32 from being deformed by the bolt.

[0032] A plurality of fiber Bragg grating strain gauges are provided, and the plurality of fiber Bragg grating strain gauges are connected in series through an optical fiber 35 and connected to a demodulator 36 . The demodulator 36 demodulates the strain signal and measures and monitors the strain response at different positions of the wind turbine tower in real time.

[0033] The positioning protection module 2 includes a U-shaped groove 21 and a positioning block 23. The U-shaped groove 21 is a rectangular structure with uniform thickness and a handle on the upper part. It has a larger opening at the bottom for installing a magnetic suction cup. The front and rear sides of the U-shaped groove 21 are provided with threaded holes, which cooperate with the positioning bolts 22. The positioning bolts 22 pass through the threaded holes and connect with the positioning block 23 to fix the magnetic suction cup. The positioning block 23 is arranged on the inner side of the U-shaped groove 21, and the end of the U-shaped groove 21 is connected to the magnetic suction cup through the fixing bolts 24. When in use, ensure that the inner surface of the U-shaped groove 21 is in close contact with the front panel 11 and the top cover 14, and the positioning block 23 is in close contact with the rear panel 13. A positioning hole is provided on the side of the U-shaped groove 21, which cooperates with the fixing bolts 24 to fix the magnetic suction cup. After the equipment is installed on the wind turbine tower, the positioning protection module 2 should be removed immediately, and the equipment can work normally.

[0034] The production and installation process is as follows: Before use, determine a reasonable layout plan and a sufficiently long optical fiber 35 based on the height of the wind turbine tower, the number of equipment to be installed, etc. After the device is prepared, the detailed installation steps are as follows:

[0035] Before installing the equipment, pre-installation is required. Install the elastomer 32 with the fiber Bragg grating strain gauge in the slot 31 and fix it with a gasket 33 and a bolt 34. After completion, place the equipment in the U-shaped groove 21 and position the two magnetic suction cups. During installation, ensure that the inner surface of the U-shaped groove 21 is in close contact with the front panel 11 and the top cover 14 of the magnetic suction cup, and the positioning block 23 is in close contact with the rear panel 13 of the magnetic suction cup. Then tighten the positioning bolt 22 and the fixing bolt 24 to ensure that the two magnetic suction cups will not be displaced relative to each other, and protect the elastomer 32 and the fiber Bragg grating strain gauge from deformation during the transportation and installation of the equipment. After completion, the equipment is as follows Figure 1 shown.

[0036] After the pre-installation is completed, install the equipment at the position to be tested on the tower. During installation, rotate the operating lever 16 to the "on" state, and the equipment can be adsorbed on the tower. During the installation process, the upper magnetic suction cup should be installed first, and the level and plumb line should be used to ensure that the equipment is parallel to the axis of the wind turbine tower. After the equipment is fixed to the tower, the positioning protection module 2 needs to be removed.

[0037] After all equipment is installed, the optical fiber 35 is arranged. One end of the optical fiber 35 is connected to the synchronous acquisition module, and the other end is used to connect the fiber grating strain gauges on different equipment in series, such as Figure 6 As shown, after the connection and testing are completed, the strain gauge and the optical fiber are sealed to achieve real-time collection and monitoring of the strain signal.

[0038] Therefore, the present invention adopts the above-mentioned dynamic strain response measurement device of the adsorption wind turbine tower. The present invention has a simple structure, is easy to maintain, and is easy to install. There is no need to grind or damage the tower during installation, and it is easy to adjust the measurement point position; the present invention uses fiber grating strain gauges, which have high measurement accuracy and reliable results. The strain gauges can be connected in series through optical fibers, which is convenient for cable layout and signal collection; the present invention transmits signals through optical fibers, has a long transmission distance, has strong anti-electromagnetic interference ability, and the signal is not easily contaminated by the environment.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A dynamic strain response measurement device for an adsorption type wind turbine tower, characterized in that: It includes an equipment fixing module, a positioning protection module and a measurement and monitoring module, wherein the measurement and monitoring module is arranged on the equipment fixing module, the outside of the equipment fixing module is connected to the positioning protection module, the positioning protection module determines the position of the equipment fixing module and protects the equipment fixing module, and the measurement and monitoring module monitors the deformation response at different positions of the wind turbine tower; The equipment fixing module is composed of two magnetic suction cups, and the front ends of the two magnetic suction cups are each provided with an operating rod, and the operating rod passes through the front panel and is connected to one end of the rotating drum. A notch is provided inside the rotating drum, and a rectangular magnet is installed in the notch. The other end of the rotating drum is connected to the rear panel through a rear bearing; The magnetic suction cup is arranged as a cubic structure, a cylindrical cavity is opened inside the magnetic suction cup, a boss is arranged on the upper part of the magnetic suction cup, linearly arranged fixed strong magnets are fixed on both sides of the boss, a top cover is arranged on the upper part of the fixed strong magnet, the top cover is connected to the front panel and the rear panel by bolts, a card slot is arranged on the top cover, and the card slot is connected to the measurement and monitoring module.

2. The dynamic strain response measurement device of an adsorption type wind turbine tower according to claim 1 is characterized in that: The measurement and monitoring module includes an elastomer and a fiber optic Bragg grating strain gauge, the fiber optic Bragg grating strain gauge is pasted on the elastomer, both ends of the elastomer are adapted to the slot, the slot and the elastomer are connected by a bolt and a gasket, and a circular hole is opened in the middle of the gasket.

3. The dynamic strain response measurement device of an adsorption type wind turbine tower according to claim 2, characterized in that: The elastic body is a columnar structure, the diameter of the elastic body decreases from both ends to the middle, and the bending rigidity of the elastic body is smaller than the bending rigidity of the wind turbine tower.

4. The dynamic strain response measuring device of an adsorption type wind turbine tower according to claim 3 is characterized in that: The fiber grating strain gauges are provided in plurality, and the plurality of fiber grating strain gauges are connected in series through optical fibers and connected to a demodulator, and the demodulator demodulates the strain signal to measure and monitor the strain response at different positions of the wind turbine tower in real time.

5. The dynamic strain response measurement device for an adsorption type wind turbine tower according to claim 4, characterized in that: The positioning and protection module includes a positioning block and a U-shaped groove. The U-shaped groove is a rectangular structure with a handle on the upper part. The front and back sides of the U-shaped groove are provided with threaded holes. The threaded holes cooperate with positioning bolts. The positioning bolts pass through the threaded holes and are connected to the positioning block. The positioning block is arranged on the inner side of the U-shaped groove, and the end of the U-shaped groove is connected to the magnetic suction cup through a fixing bolt.

Images