A wind turbine tower inclination monitoring device
By installing fiber Bragg gratings and FBG demodulators on the outer wall of the wind turbine tower, combined with temperature compensation and protection measures, the problem of laser sensors being affected by weather and vibration was solved, achieving high stability and low false alarm rate in wind turbine tower tilt monitoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SDIC GUANGXI WIND POWER CO LTD
- Filing Date
- 2025-08-25
- Publication Date
- 2026-07-28
AI Technical Summary
In wind turbine tower tilt monitoring equipment, laser sensors are greatly affected by weather. Vibration causes the beam to jitter, making it difficult to distinguish between instantaneous vibration offset and continuous tower tilt offset, which easily leads to false alarms.
The fiber Bragg grating and FBG demodulator are used. The fiber Bragg grating is arranged in four orthogonal directions along the outer wall of the wind turbine tower. Combined with temperature compensation fiber and protective corrugated pipe, it is fixed by clamps. The wavelength offset signal of the fiber Bragg grating is converted into an electrical signal by the FBG demodulator, and the tilt angle is calculated by the data processing controller.
It improves the stability and accuracy of monitoring, reduces false alarm rate, has strong anti-interference ability, and is easy to install and maintain.
Smart Images
Figure CN224566248U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power generation equipment condition monitoring technology, specifically a wind turbine tower tilt monitoring device. Background Technology
[0002] The wind turbine tower is the core supporting structure of a wind turbine generator set, primarily used to support components such as the nacelle and blades, while also providing installation space for the unit's electrical equipment and control systems. The tower mainly serves a supporting role in the wind turbine generator set, while also absorbing vibrations. The tower bears complex and variable loads such as thrust, bending moment, and torque, causing it to sway and twist to a certain extent during wind turbine generator set operation. Furthermore, the tower is also affected by material deformation, component failure, and foundation settlement, leading to tilting. Therefore, monitoring the tilt of the wind turbine tower is necessary.
[0003] For example, a wind turbine tower tilt monitoring device, application number 202421583466.4, includes a support frame, two bolts, a laser transmitter and receiver, a support plate, a reflector, and a fixing mechanism. One end of each of the two bolts passes through the support frame and is tightened onto the wind turbine tower. The support plate is set on the ground, and the reflector is mounted on the support plate. In the aforementioned patent, the wind turbine tower tilt monitoring uses a laser transmitter and receiver. The propagation of the laser beam is easily affected by weather conditions such as rain, snow, fog, and dust storms: rain causes beam scattering, fog causes beam attenuation, and dust storms may obscure the surface of the target detection ring, causing the laser to fail to reach the detection ring stably or resulting in erratic reflected signals. This can lead to increased measurement errors or even complete failure. Furthermore, during wind turbine operation, the tower vibrates continuously due to blade rotation. Since the top rotating disk and laser sensor are directly mounted on the outer wall of the tower, vibration causes the laser beam to "jitter," resulting in high-frequency fluctuations in the beam's landing point on the target detection ring. This makes it difficult to distinguish between "instantaneous offset caused by vibration" and "continuous offset caused by tower tilt," easily leading to false alarms. Therefore, we propose a wind turbine tower tilt monitoring device to address the aforementioned problems. Utility Model Content
[0004] The purpose of this invention is to provide a wind turbine tower tilt monitoring device to solve the problems mentioned in the background art, which are greatly affected by weather and vibration, the laser sensor for wind turbine tower tilt monitoring is unstable, the tower vibration during wind turbine operation causes the laser beam to jitter and the landing point to fluctuate at high frequency, making it difficult to distinguish between instantaneous vibration offset and continuous tower tilt offset, and easily causing false alarms.
[0005] To achieve the above objectives, this utility model provides the following technical solution:
[0006] A wind turbine tower tilt monitoring device includes a wind turbine tower and a tilt monitoring device for monitoring the tilt of the wind turbine tower. The tilt monitoring device includes a fiber Bragg grating, a fixing component, and an FBG demodulator.
[0007] The number of fiber Bragg gratings is four, which are arranged along the four orthogonal directions of east, south, west and north on the outer wall of the wind turbine tower according to the diameter of the tower. The fiber Bragg gratings are attached to the outer wall of the wind turbine tower with epoxy resin and fixed by adhesive dots every 50cm along the length of the fiber Bragg gratings.
[0008] The fastener includes a protective corrugated pipe and a clamp. The outer wall of the protective corrugated pipe has a slot, and it is fitted onto the outside of the fiber Bragg grating through the slot. The clamp has a ring structure with four fixing slots evenly distributed inside. The clamp is fitted onto the outside of the wind turbine tower, and the four fixing slots are respectively engaged with the outside of the four protective corrugated pipes. A silicone pad is pasted on the inside of the fixing slot.
[0009] Preferably, the bottom of the wind turbine tower is provided with an optical fiber junction box, which is 1.5m above the ground. The optical fiber junction box is provided with an optical fiber fusion splice plate, which is fused to the bottom end of the fiber Bragg grating. The other end of the fiber Bragg grating is connected to the FBG demodulator.
[0010] Preferably, it also includes a temperature compensation fiber, which is encapsulated in a heat insulation sleeve and installed parallel to one side of the fiber Bragg grating, and the heat insulation sleeve does not contact the wind turbine tower; the outer wall of the wind turbine tower is provided with a bracket, and the heat insulation sleeve is fixed on the bracket. The bracket is made of 304 stainless steel and is set every 2m along the length of the temperature compensation fiber. The signal output end of the temperature compensation fiber is connected to the signal input end of the FBG demodulator.
[0011] Preferably, the clamp is made of 304 stainless steel and the silicone pad is 0.5mm thick.
[0012] Preferably, the protective corrugated pipe is made of polytetrafluoroethylene and has a diameter of 3mm.
[0013] Preferably, the clamps are set up every 2m along the height of the wind turbine tower.
[0014] Compared with the prior art, the beneficial effects of this utility model are:
[0015] 1. The tilt monitoring equipment of this application has strong anti-interference ability: it adopts fiber Bragg grating to replace laser transmitter and receiver, which avoids the influence of weather on beam propagation and improves the stability and accuracy of monitoring.
[0016] 2. Reduce false alarm rate: The fiber Bragg grating is bonded to the outer wall of the wind turbine tower with epoxy resin and fixed with protective corrugated pipe and clamps. This can effectively reduce the impact of tower vibration on monitoring and better distinguish between instantaneous offset caused by vibration and continuous offset caused by tower tilt, thus reducing the false alarm rate.
[0017] 3. Easy installation and maintenance: A set of clamps is installed every 2 meters along the height of the wind turbine tower, and is made of 304 stainless steel with silicone pads, ensuring both installation stability and ease of maintenance. The fiber optic junction box is located at the bottom of the tower, 1.5 meters above the ground, for convenient wiring and maintenance. Attached Figure Description
[0018] Figure 1 This is an isometric view of the present invention;
[0019] Figure 2 This is a schematic diagram of the installation of the tilt monitoring device and the wind turbine tower of this utility model;
[0020] Figure 3 For the present utility model Figure 2 Enlarged view of area A in the middle;
[0021] Figure 4 This is a schematic diagram of the installation structure of the protective corrugated pipe of this utility model with the wind turbine tower via a clamp;
[0022] Figure 5 This is a schematic diagram of the installation structure of the heat insulation sleeve and bracket of this utility model;
[0023] Figure 6 This is a block diagram of the connection module of the tilt monitoring and control equipment of this utility model.
[0024] In the diagram: 1. Wind turbine tower; 11. Fiber optic junction box; 101. Bracket; 2. Tilt monitoring equipment; 21. Fiber Bragg grating; 22. Fixture; 221. Protective corrugated pipe; 222. Clamp; 223. Groove; 224. Fixing groove; 225. Silicone pad. Detailed Implementation
[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0026] Please see Figure 1 , Figure 2 and Figure 6As shown, a wind turbine tower tilt monitoring device includes a wind turbine tower 1 and a tilt monitoring device 2 for monitoring the tilt of the wind turbine tower 1. The tilt monitoring device 2 includes a fiber Bragg grating 21, a fixing component 22, an FBG demodulator, and a temperature compensation fiber. There are four fiber Bragg gratings 21, which are arranged along the four orthogonal directions (east, south, west, and north) of the outer wall of the wind turbine tower 1 according to its diameter. The fiber Bragg gratings 21 are bonded to the outer wall of the wind turbine tower 1 with epoxy resin, and are fixed every 50cm along the length of the fiber Bragg gratings 21 by adhesive dots to ensure synchronous deformation. The temperature compensation fiber is encapsulated in a heat insulation sleeve and installed parallel to one side of the fiber Bragg gratings 21, and the heat insulation sleeve does not contact the wind turbine tower 1. A bracket 101 is provided on the outer wall of the wind turbine tower 1, and the heat insulation sleeve is fixed on the bracket 101. The bracket 101 is made of 304 stainless steel, and a set is set every 2m along the length of the temperature compensation fiber. The signal output end of the temperature compensation fiber is connected to the signal input end of the FBG demodulator. A fiber optic junction box 11 is located at the bottom of the wind turbine tower 1, 1.5m above the ground. Inside the junction box 11 is a fiber optic fusion splice tray, which is fused to the bottom end of a fiber Bragg grating 21. The other end of the fiber Bragg grating 21 is connected to an FBG demodulator. The FBG demodulator is installed in a control box at the bottom of the wind turbine tower 1 or in a ground-based equipment room near the junction box 11. Its signal input is connected via optical fiber to the end of the fiber Bragg grating 21 furthest from the junction box, converting the wavelength shift signal caused by deformation of the fiber Bragg grating 21 into an electrical signal. The control box integrates a data processing controller, whose signal input is connected to the signal output of the FBG demodulator. The data processing controller has a built-in algorithm module to convert the strain data of the fiber Bragg grating 21 into the tower tilt angle; it also has a 4G or Ethernet communication module to upload tilt monitoring data to a remote monitoring platform.
[0027] It should be noted that in this embodiment, the wavelength shift of the fiber Bragg grating 21 is not only caused by tower strain (tilt), but also affected by temperature changes (temperature rise / fall will cause the fiber to expand and contract, resulting in additional wavelength shift). The temperature-compensated fiber transmits the ambient temperature signal to the FBG demodulator. The demodulator compares the wavelength shift difference between the fiber Bragg grating 21 and the temperature-compensated fiber to eliminate the interference of temperature factors on the tilt monitoring signal, and retains only the effective strain signal generated by the tower deformation, thereby improving the accuracy of the tilt angle calculation.
[0028] When the wind turbine tower 1 tilts, the fiber Bragg gratings 21 in the east, south, west, and north directions are stretched or compressed along with the tower deformation, causing a shift in the center wavelength of the reflected light. The shift is positively correlated with the tower strain. The FBG demodulator receives the wavelength shift signal of the fiber Bragg gratings 21 in real time, converts it into a corresponding electrical signal (strain data), and transmits it to the data processing controller. The algorithm module of the data processing controller, based on the four-directional strain data and parameters such as the diameter and height of the wind turbine tower 1, calculates the tilt angle (including direction and magnitude) of the tower using geometric relationships and material mechanics formulas. The data processing controller uploads the tilt angle, real-time strain, and other data to a remote monitoring platform via the communication module. The platform stores, displays, and analyzes the data, triggering an alarm when the tilt angle exceeds a preset threshold.
[0029] Please refer to the figure. Figure 2 - Figure 5 As shown, the fixing component 22 includes a protective corrugated tube 221 and a clamp 222. The fiber Bragg grating 21 is covered with a protective corrugated tube 221 made of polytetrafluoroethylene. The protective corrugated tube 221 has a diameter of 3mm and a groove 223 is opened on the outer wall of the protective corrugated tube 221. The fiber can be easily installed through the groove 223, which plays a role in preventing wear and corrosion. It can isolate the fiber from environmental factors such as dust, rainwater, and ultraviolet rays on the outer wall of the wind turbine tower 1 and prevent wear caused by direct friction between the fiber and the tower surface. It protects the sensing stability of the fiber Bragg grating 21 and ensures that its strain signal is not affected by physical damage. The clamps 222 have a ring structure, with a set of ring clamps 222 installed every 2m along the tower height. The clamps 222 are made of 304 stainless steel, and the four fixing slots 224 inside are engaged with four protective corrugated tubes 221. A 0.5mm thick silicone pad 225 is pasted on the inside of the fixing slots 224. The elastic deformation of the silicone pad 225 tightly fits the protective corrugated tube 221, ensuring that the optical fiber does not undergo relative displacement when the tower vibrates (ensuring synchronization with the tower deformation) and avoiding squeezing damage caused by direct contact between the rigid clamps 222 and the corrugated tube. This further stabilizes the optical fiber deployment position and reduces signal interference caused by non-tilt factors (such as wind swaying), ensuring both stable fixation and avoiding damage to the corrugated tube. The temperature-compensated optical fiber is encapsulated in a heat-insulating sleeve and fixed to the outer wall of the tower by 304 stainless steel brackets 101 (set every 2m). The heat-insulating sleeve does not contact the tower. The temperature-compensated optical fiber signal is connected to an FBG demodulator for temperature correction of the tilt monitoring signal.
[0030] The fastener 22 ensures the physical stability of the fiber optic sensor through both protection and stabilization, while the temperature compensation structure eliminates the interference of ambient temperature on the signal. Together, they ensure that the fiber Bragg grating 21 can accurately capture the strain caused by the tower tilt, providing a reliable raw signal for the subsequent data processing controller to calculate the tilt angle.
[0031] Workflow: When the wind turbine tower 1 tilts, the fiber Bragg gratings 21 in the east, south, west, and north directions are stretched or compressed along with the tower deformation, causing a shift in the center wavelength of their reflected light. The amount of shift is positively correlated with the tower strain. The FBG demodulator is installed in the control box at the bottom of the wind turbine tower 1. Its signal input end is connected to the end of the fiber Bragg grating 21 away from the junction box via an optical fiber, receiving the wavelength shift signal of the fiber Bragg grating 21 in real time. Since the wavelength shift of the fiber Bragg grating 21 is affected by temperature changes, the demodulator compares its wavelength shift difference with that of the temperature-compensated fiber to eliminate the influence of temperature factors, retaining only the effective strain signal generated by the tower deformation, and converting it into an electrical signal (strain data). The signal input end of the data processing controller in the control box is connected to the signal output end of the FBG demodulator to receive the demodulated strain data. Its built-in algorithm module, based on the four-directional strain data and combined with parameters such as the diameter and height of the wind turbine tower 1, calculates the tilt angle of the tower through geometric relationships and material mechanics formulas. The data processing controller uploads data such as tilt angle and real-time strain to the remote monitoring platform via its built-in 4G or Ethernet modules. The platform stores, displays, and analyzes the data, triggering an alarm when the tilt angle exceeds a preset threshold, thus achieving effective monitoring and management of the wind turbine tower's tilt status.
[0032] The contents not described in detail in this specification are existing technologies known to those skilled in the art.
[0033] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A wind turbine tower tilt monitoring device, comprising a wind turbine tower (1) and a tilt monitoring device (2) for monitoring the tilt of the wind turbine tower (1), characterized in that: The tilt monitoring device (2) includes a fiber Bragg grating (21), a fixing component (22), and an FBG demodulator; The number of fiber Bragg gratings (21) is four, which are arranged along the four orthogonal directions of the outer wall of the wind turbine tower (1) according to the diameter of the tower. The fiber Bragg gratings (21) are attached to the outer wall of the wind turbine tower (1) with epoxy resin and fixed by adhesive every 50cm along the length of the fiber Bragg gratings (21). The fastener (22) includes a protective corrugated pipe (221) and a clamp (222). The outer wall of the protective corrugated pipe (221) has a slot (223) and is fitted onto the outside of the fiber Bragg grating (21) through the slot (223). The clamp (222) has a ring structure with four fixing slots (224) evenly distributed inside. The clamp (222) is fitted onto the outside of the wind turbine tower (1), and the four fixing slots (224) are respectively engaged with the outside of the four protective corrugated pipes (221). A silicone pad (225) is pasted on the inside of the fixing slot (224).
2. The wind turbine tower tilt monitoring device according to claim 1, characterized in that: The bottom of the wind turbine tower (1) is provided with an optical fiber junction box (11), which is 1.5m above the ground. Inside the optical fiber junction box (11) is an optical fiber fusion splice plate, which is fused to the bottom end of the fiber Bragg grating (21). The other end of the fiber Bragg grating (21) is connected to the FBG demodulator.
3. The wind turbine tower tilt monitoring device according to claim 1, characterized in that, It also includes a temperature compensation fiber, which is encapsulated in a heat insulation sleeve and installed parallel to one side of the fiber Bragg grating (21), and the heat insulation sleeve does not contact the wind turbine tower (1); the outer wall of the wind turbine tower (1) is provided with a bracket (101), the heat insulation sleeve is fixed on the bracket (101), the bracket (101) is made of 304 stainless steel, and a set is set every 2m along the length of the temperature compensation fiber, and the signal output end of the temperature compensation fiber is connected to the signal input end of the FBG demodulator.
4. The wind turbine tower tilt monitoring device according to claim 1, characterized in that, The clamp (222) is made of 304 stainless steel, and the silicone pad (225) has a thickness of 0.5mm.
5. The wind turbine tower tilt monitoring device according to claim 1, characterized in that, The protective corrugated pipe (221) is made of polytetrafluoroethylene and has a diameter of 3mm.
6. The wind turbine tower tilt monitoring device according to claim 1, characterized in that, The clamps (222) are set every 2m along the height direction of the wind turbine tower (1).