A method for monitoring dynamic characteristics of a fan blade by utilizing beidou fusion laser data

Abstract

The application provides a method for monitoring dynamic characteristics of a fan blade by using Beidou fusion laser data, comprising the following steps: S1, respectively acquiring a deformation structural mechanics characteristic curve f(D)=d of a fan tower drum and a deformation structural mechanics characteristic curve g(l)=L of a fan blade; S2, deriving a deformation displacement d'=f(D') of the tower drum at a lowest plane swept by a tip end of the fan blade in the operation of the fan from f(D)=d, deriving a deformation displacement L'=g(l') of the tip end of the fan blade in the operation of the fan from g(l)=L, and obtaining a feathering angle γ of the fan blade; and S3, obtaining a real-time clearance distance of the fan blade in the operation of the fan according to the data of d', L' and γ obtained in the step S2. The application can obtain the real-time clearance distance of the fan blade, and is convenient for timely feedback and control of the fan, and guarantees the safe operation of the fan.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, specifically to a method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data. Background Technology

[0002] Wind turbine blade clearance refers to the minimum distance between the blade tip and the tower surface during wind turbine operation, and it is crucial for wind turbine operational safety. Currently, wind turbines are becoming increasingly powerful, and their blades are also becoming longer. With the increase in blade length, blade stiffness decreases accordingly. At higher wind speeds, the deformation at the blade tip is significant, and under extreme turbulence conditions, this can lead to serious accidents such as blade tip swiping the tower, affecting the safe operation of the wind turbine. Therefore, real-time monitoring of whether the blade clearance remains within the designed safe range is of paramount importance for ensuring the safe operation of wind turbines.

[0003] Existing wind turbine blade clearance monitoring technologies often suffer from the following problems:

[0004] (1) Installing video cameras or lidar on the nacelle. This solution mainly uses optical methods to detect the clearance between the blades, that is, reconstructing the three-dimensional model of the blades through machine vision or laser point cloud algorithms, and then calculating the clearance between the blades and the tower. Since video and laser measurements have long distances and large measurement ranges, this method is easily affected by adverse weather conditions such as rain, fog, and snow, as well as poor visibility at night. Furthermore, the accuracy of the calculation results is highly dependent on the algorithm. Currently, the algorithm technology for calculating the clearance distance between wind turbine blades using images and laser point cloud data is not yet mature. At the same time, the calculation of image or point cloud data requires a lot of computing resources. Therefore, the reliability and cost of this technical solution are not ideal.

[0005] (2) Multiple millimeter-wave radars are evenly distributed along the circumference of the tower at a position flush with the tip of the wind turbine blades. The clearance distance between the blades is calculated by measuring the distances with the radars. Compared with placing the radars at the base of the tower, this method transforms the calculation method from a three-dimensional spatial problem to a two-dimensional planar problem, greatly simplifying the calculation method. However, it is very difficult to implement this method. On the one hand, the installation location of wind turbines is often remote and the terrain is steep. On the other hand, the tip of the wind turbine blades is generally about 20 meters above the ground, requiring a large aerial work platform for operation.

[0006] (3) A method to calculate blade clearance by installing deformation sensors at the blade tip and converting deformation into displacement based on the blade's calibrated mechanical properties. This method presents significant challenges in installing sensors at the blade tip, especially for in-service wind turbines. Furthermore, this method assumes that the blade tip deformation always faces the tower, neglecting the angle between the blade deformation direction and the tower under pitch control conditions, leading to certain errors in the calculation results.

[0007] In summary, providing a method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data to address the problems of poor reliability, large errors, and operational difficulties in monitoring blade clearance in existing technologies is of great significance for ensuring the safe operation of wind turbines. Summary of the Invention

[0008] The purpose of this invention is to provide a method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data. The specific technical solution is as follows:

[0009] A method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data includes:

[0010] Step S1: Conduct aerodynamic experiments on the wind turbine or its scaled-down model in a wind tunnel, or directly measure the operating wind turbine to obtain the deformation structural mechanical characteristic curve f(D)=d of the wind turbine tower and the deformation structural mechanical characteristic curve g(l)=L of the wind turbine blade, where D represents the displacement of the top of the tower, d represents the displacement of the tower at the lowest plane swept by the tip of the wind turbine blade, L represents the displacement of the tip of the wind turbine blade, and l represents the displacement at the bending characteristic point at the root of the wind turbine blade.

[0011] Step S2: Install a Beidou receiver on the top of the wind turbine nacelle and use the spatial positioning function of the Beidou receiver to measure the deformation displacement D′ of the top of the tower during wind turbine operation; derive the deformation displacement d′=f(D′) of the tower at the lowest plane swept by the tip of the wind turbine blades during wind turbine operation from f(D)=d.

[0012] A third laser rangefinder P1 is installed on the top of the wind turbine nacelle, and the pitch angle of P1 is set to α1; when the wind turbine is stationary, the distance measurement data of P1 to the wind turbine blades is s. 10 When the wind turbine is running, the distance measurement data of P1 to the wind turbine blades is s. 11 The deformation displacement l′ = (s) at the bending characteristic point at the root of the wind turbine blades during operation is obtained by using trigonometric functions. 10 -s 11 )cosα1;From g(l)=L, we can derive the deformation displacement L′=g(l′) at the tip of the fan blade during operation;

[0013] A first laser rangefinder P2 and a second laser rangefinder P3 are installed on the top of the wind turbine nacelle. The pitch angle of P2 is set to α2 and the yaw angle to β2, and the pitch angle of P3 is set to α3 and the yaw angle to β3. When the wind turbine blades are in operation, the laser from P2 illuminates the first ranging point A on the wind turbine blade, and the corresponding ranging data is s. 20 The P3 laser illuminates the second ranging point B on the wind turbine blade, and the corresponding ranging data is s. 30When the wind turbine blades retract, the P2 laser illuminates the third ranging point A1 on the wind turbine blade, and the corresponding ranging data is s. 21 The P3 laser illuminates the fourth ranging point B1 on the wind turbine blade, and the corresponding ranging data is s. 31 Among them, the projection points of the first measuring point A, the second measuring point B, the third measuring point A1 and the fourth measuring point B1 on the horizontal plane where P2 and P3 are located are A′, B′, A1′ and B1′ respectively, and the condensation angle γ of the wind turbine blade after condensation rotation is the angle between the straight line A′B′ and the straight line A1′B1′.

[0014] Step S3: Based on the d′, L′ and γ data obtained in step S2, the real-time clearance distance of the wind turbine blades during wind turbine operation is obtained as k′=k+d′-L′cosγ; where k is the initial clearance distance set for the wind turbine blades.

[0015] Optionally, in step S2, the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 are all installed on the top of the cabin and are set as an integrated device.

[0016] Optionally, in step S2, the process of obtaining the propeller angle γ is as follows:

[0017] Taking the location of the integrated device containing the first laser rangefinder P2 and the second laser rangefinder P3 as the origin O, the length of A′B′ in △OA′B′ can be obtained using the law of cosines:

[0018] |A′B′| 2 =|OA′| 2 +|OB′| 2 -2|OA′|·|OB′|cos|β2-β3|;

[0019] Where, |OA′|=|OA|×cosα2=s 20 ·cosα2;|OB′|=|OB|×cosα3=s 30 ·cosα3;

[0020] In triangle OA′B′, the measure of ∠OA′B′ can be found using the Law of Sines:

[0021] Therefore

[0022] In △OA′1B′1, the length of A′1B′1 can be found using the Law of Cosines:

[0023] |A′1B′1| 2 =|OA′1| 2 +|OB′1| 2-2|OA′1|·|OB′1|cos|β2-β3|;

[0024] Where, |OA′1|=|OA1|×cosα2=s 21 ·cosα2;|OB1′|=|OB1|×cosα3=s 31 ·cosα3;

[0025] In △OA′1B′1, the measure of ∠OA′1B′1 can be obtained using the Law of Sines:

[0026]

[0027] Therefore

[0028] The angle of oar retraction γ = ∠OA′1B′1 - ∠OA′B′.

[0029] Optionally, in step S1, f(D) = d = -8 × 10 -6 D 2 +0.0817D+1.0086.

[0030] Optionally, in step S1, g(l) = L = 0.0296l 2 -3.1688l+144.25.

[0031] Optionally, step S2 may further include selecting valid data of the blade in each rotation cycle, which is used to select valid data from all data of the blade monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2 and the second laser rangefinder P3 in each rotation cycle.

[0032] The valid data refers to all data monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 during the time period from when the wind turbine blade enters the measurement range of P2 to when it leaves the measurement range of P3 during each rotation cycle; or, the valid data refers to all data monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 during the time period from when the wind turbine blade enters the measurement range of P3 to when it leaves the measurement range of P2 during each rotation cycle.

[0033] Optionally, the time period from when the fan blade enters the measurement range of P2 to when it leaves the measurement range of P3 includes the state of the fan blade being vertically upward; or, the time period from when the fan blade enters the measurement range of P3 to when it leaves the measurement range of P2 includes the state of the fan blade being vertically upward.

[0034] Optionally, in the valid data, assume that the data quantities corresponding to the BeiDou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 are M0, M1, M2, and M3, respectively; where the following proportional relationship exists: M0 ∝ f0, and ω is the angular velocity of the wind turbine blades, f0 is the acquisition frequency of the Beidou receiver, f1 is the acquisition frequency of the third laser rangefinder P1, f2 is the acquisition frequency of the first laser rangefinder P2, and f3 is the acquisition frequency of the second laser rangefinder P3.

[0035] Optionally, the values ​​of M0, M1, M2, and M3 can all be any integers from 2 to 6.

[0036] Optionally, when using valid data from the BeiDou receiver, the average of M0 data points is taken before use; when using valid data from the third laser rangefinder P1, the average of M1 data points is taken before use; when using valid data from the first laser rangefinder P2, the average of M2 data points is taken before use; and when using valid data from the second laser rangefinder P3, the average of M3 data points is taken before use.

[0037] The application of the technical solution of the present invention has at least the following beneficial effects:

[0038] This invention provides a method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data. Steps S1-S3 are combined to obtain the real-time clearance distance of the wind turbine blades during operation, facilitating timely feedback and control of the wind turbine and ensuring safe operation. Specifically, in step S1, the deformation structural mechanical characteristic curves f(D) = d of the wind turbine tower and g(l) = L of the wind turbine blades are obtained respectively. In step S2, a method combining a BeiDou receiver, a third laser rangefinder P1, a first laser rangefinder P2, and a second laser rangefinder P3 is used to measure the dynamic characteristics of the wind turbine blades in real time, including the deformation displacement d′ = f(D′) of the tower at the lowest plane swept by the blade tip, the deformation displacement L′ = g(l′) of the blade tip, and the blade tip angle γ. In step S3, the blade clearance distance is obtained according to k′ = k + d′ - L′cosγ, demonstrating high reliability and low error. Therefore, this invention can obtain the blade clearance distance in real time, facilitating timely feedback and control of the wind turbine and ensuring its safe operation. Furthermore, this invention mounts the BeiDou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 all on the top of the nacelle, simplifying installation and reducing operational difficulty.

[0039] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0040] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0041] Figure 1 This is a schematic diagram of the overall structure of a wind turbine blade dynamic feature monitoring using BeiDou fusion laser data according to an embodiment of the present invention;

[0042] Figure 2 yes Figure 1 Schematic diagram of wind turbine tower deformation ( Figure 2 The direction of the middle arrow indicates the direction of the vertical force exerted by the wind turbine blades on the tower.

[0043] Figure 3 yes Figure 1 Schematic diagram of blade deformation of medium wind turbine ( Figure 3 The direction of the middle arrow indicates the wind direction;

[0044] Figure 4 These are scatter plots and fitted curves showing the relationship between D and d for the tower under different wind conditions.

[0045] Figure 5 These are scatter plots and fitted curves showing the L and l values ​​of wind turbine blades under different wind conditions.

[0046] Figure 6 This is a schematic diagram showing the displacement of the bending feature point at the root of the wind turbine blade under the action of wind force.

[0047] Figure 7 This is a schematic diagram illustrating the measurement data of the wind turbine blade's blade tip angle.

[0048] Figure 8 This is a top view of the wind turbine blades at the blade retraction angle;

[0049] Figure 9 This is a schematic diagram showing the real-time clearance distance between the fan blades during fan operation.

[0050] Among them, 1. wind turbine blade, 2. nacelle, 3. tower, 4. integrated device, 5. bending feature point at the root of the wind turbine blade, and 6. angular feature plane at the root of the blade. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0052] Example:

[0053] See Figure 1-3 A method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data includes:

[0054] Step S1: Conduct aerodynamic experiments on the wind turbine or its scaled-down model in a wind tunnel, or directly measure the operating wind turbine to obtain the deformation structural mechanical characteristic curve f(D) = d of the wind turbine tower 3 and the deformation structural mechanical characteristic curve g(l) = L of the wind turbine blade 1, where D represents the top displacement of the tower 3, d represents the displacement of the tower 3 at the lowest plane swept by the tip of the wind turbine blade 1, L represents the tip displacement of the wind turbine blade 1, and l represents the displacement at the bending feature point 5 at the root of the wind turbine blade.

[0055] Specifically, the main stress point for the deformation of tower 3 is the vertical pressure transmitted to nacelle 2 via the blades, followed by the wind resistance of the tower 3's own windward cross-section. Since the diameter of tower 3 is relatively small compared to its height, and tower 3 is a smooth cylinder, the wind resistance of its windward cross-section can be largely ignored. Therefore, the main consideration is the deformation of the wind turbine tower 3 under the vertical pressure transmitted to nacelle 2 by the blades. The mechanical characteristic curve is obtained by establishing a scaled-down model of tower 3 and conducting tests. The approximate deflection calculation formula is as follows:

[0056] Where: Y max Let F represent the maximum deflection of tower 3, F represent the concentrated load on tower 3, h represent the height of tower 3, E represent Young's modulus, and I represent the moment of inertia.

[0057] From the deflection calculation formula, it can be seen that, given a constant value of F and a fixed material property for tower 3, the deflection changes with the height of tower 3 and is directly proportional to the cube of the height of tower 3. Therefore, D and d have the following theoretical proportional relationship:

[0058]

[0059] Right now:

[0060] Among them, h d h represents the height of the tower 3 at the lowest plane swept by the tip of the wind turbine blade 1. D This indicates the height of the top of tower 3.

[0061] For a wind turbine, h d and h DSince the values ​​are fixed, D and d theoretically have a linear proportional relationship. However, due to various factors such as the variable cross-section of tower 3 and material properties, the two are not strictly proportional. Therefore, the correspondence between the top displacement of tower 3 and the displacement of tower 3 at the lowest plane swept by the tip of wind turbine blade 1 is fitted using a second-order polynomial with the least squares method. The fitted function is of the form d = a1D. 2 +b1D+c1;

[0062] Specifically, taking a certain operating wind turbine as an example, measurements were directly taken under different operating conditions. Using a total station in conjunction with high-speed photogrammetry, the correspondence between the displacement D of the top of the tower 3 and the displacement d of the tower 3 at the lowest point where the tip of the wind turbine blade 1 sweeps across the ground under different wind conditions was obtained. A scatter plot was then drawn as follows: Figure 4 The following relationship was obtained by fitting using the least squares method:

[0063] f(D) = d = -8 × 10 -6 D 2 +0.0817D+1.0086, corresponding to the correlation coefficient R. 2 =0.972.

[0064] Due to the variable cross-section design and the uneven loads on the blades, the theoretical correspondence between L and l is difficult to analyze. However, overall, there is a positive correlation between the two. Therefore, the correspondence between the tip displacement L of the wind turbine blade 1 and the displacement l at the bending characteristic point 5 at the root of the wind turbine blade is also fitted using the least squares method with a second-order polynomial. The fitted function relationship is L = a²l. 2 +b2l+c2;

[0065] Specifically, taking a certain operating wind turbine as an example (the center height of the turbine's impeller hub is 93.5m, and the rotor diameter is 155m), measurements were directly taken under different operating conditions. Using a total station in conjunction with high-speed photogrammetry, the blade tip displacement and the bending characteristic point 5 at the root of the turbine blades under different wind conditions were obtained (taken as a distance h from the root). l The displacement relationship at a location (1000-2000mm, specifically 1045mm) is plotted as follows: Figure 5 By fitting the data using the above method, the following relationship can be obtained:

[0066] g(l)=L=0.0296l 2 -3.1688l+144.25, corresponding to the correlation coefficient R. 2 =0.9815.

[0067] Step S2: Install a Beidou receiver on the top of the nacelle 2 of the wind turbine. Use the spatial positioning function of the Beidou receiver to measure the position coordinates (x1, y1) of the top of the tower 3 when it is offset during the operation of the wind turbine. Subtract the coordinates (x0, y0) of the top of the tower 3 when the wind turbine is stationary to obtain the deformation displacement D′ of the top of the tower 3 in the horizontal direction (since the ratio of the horizontal displacement of the tower 3 to the height of the tower 3 is very small, the vertical displacement of the top of the tower 3 can be ignored). From f(D)=d, we can derive the deformation displacement d′=f(D′) of the tower 3 at the lowest plane swept by the tip of the wind turbine blade 1 during wind turbine operation; specifically, we can measure the position coordinates of the top of the tower 3 at a certain moment when it is offset as (x1,y1)=(50550.9,39403.44), and the coordinates of the top of the tower 3 when the wind turbine is stationary as (x0,y0)=(50247.68,38616.17).

[0068] Calculate the horizontal deformation displacement D′ of the top of tower 3:

[0069]

[0070] d′=f(D′)=-8×10 -6 D′ 2 +0.0817D′+1.0086=64.24mm.

[0071] See Figure 6 A third laser rangefinder P1 is installed on top of the nacelle 2 of the wind turbine, and the pitch angle of P1 is set to α1. It is important to adjust the pitch angle α1 of the third laser rangefinder P1 so that it can illuminate the bending feature point 5 at the root of the blade. When the wind turbine is stationary, the distance measurement data of P1 to the wind turbine blade 1 is s. 10 When the wind turbine is running, the distance measurement data of P1 to wind turbine blade 1 is s. 11 The deformation displacement l′ = (s) at the bending characteristic point 5 at the root of the wind turbine blades during operation is obtained by using trigonometric functions. 10 -s 11 cosα1; From g(l)=L, we can derive the deformation displacement L′=g(l′) at the tip of the fan blade 1 during fan operation;

[0072] Specifically, measurements were taken of a certain operating wind turbine, and the pitch angle α1 was found to be 51.7°. 10 It is 3896.31mm, s 11 The value is 3346.02 mm. Therefore, l′ = 341.06 mm.

[0073] Furthermore, L′=g(l′)=0.0296l′ 2-3.1688l′+144.25=2506.63mm.

[0074] See Figure 7-8 A first laser rangefinder P2 and a second laser rangefinder P3 are installed on the top of the nacelle 2 of the wind turbine. The pitch angle of P2 is set to α2 (specifically 23.4°) and the heading angle is set to β2 (specifically 13.5°). The pitch angle of P3 is set to α3 (specifically 23.4°) and the heading angle is set to β3 (specifically 3°). It is important to adjust the heading angles of the first laser rangefinder P2 and the second laser rangefinder P3 so that β2 and β3 can illuminate the angular characteristic plane 6 at the root of the blade, and the laser illumination point will not leave the wind turbine blade 1 throughout the entire range of blade retraction. When the wind turbine blade 1 is in motion, the laser P2 illuminates the first ranging point A on the wind turbine blade 1, and the corresponding ranging data is s. 20 (Specific value is 2458.54mm); The P3 laser illuminates the second ranging point B on the wind turbine blade 1, and the corresponding ranging data is s. 30 (Specific value is 2413.72mm); When the wind turbine blade 1 retracts, the P2 laser illuminates the third ranging point A1 on the wind turbine blade 1, and the corresponding ranging data is s. 21 (Specific value is 2407.91mm); The P3 laser illuminates the fourth ranging point B1 on the wind turbine blade 1, and the corresponding ranging data is s. 31 (Specific value is 2463.87mm); where the first measuring point A, the second measuring point B, the third measuring point A1, and the fourth measuring point B1 are on the horizontal plane where P2 and P3 are located (i.e., Figure 7 The projection points of the xOy plane in the middle are A′, B′, A′1 and B′1 respectively. The angle γ of the wind turbine blade 1 after the blade is rotated is the angle between the line A′B′ and the line A′1B′1.

[0075] Step S3, see Figure 9 Based on the d′, L′, and γ data obtained in step S2, the real-time clearance distance of the wind turbine blade 1 during wind turbine operation is obtained as k′=k+d′-L′cosγ; where k is the initial clearance distance set for the wind turbine blade 1, with a value of 13860mm. Specifically, k′=k+d′-L′cosγ=13860+64.24-2506.63cos6.45°=11433.48mm.

[0076] In step S2, the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2 and the second laser rangefinder P3 are all installed on the central axis of the top of the cabin 2 and are set as an integrated device 4.

[0077] In step S2, the process of obtaining the paddle angle γ is as follows:

[0078] Taking the location of the integrated device 4 containing the first laser rangefinder P2 and the second laser rangefinder P3 as the origin O, the length of A′B′ in △OA′B′ can be obtained using the law of cosines:

[0079] |A′B′| 2 =|OA′| 2 +|OB′| 2 -2|OA′ | ·|OB′|cos|β2-β3|;

[0080] Where, |OA′|=|OA|×cosα2=s 20 ·cosα2;|OB′|=|OB|×cosα3=s 30 ·cosα3;

[0081] In triangle OA′B′, the measure of ∠OA′B′ can be found using the Law of Sines:

[0082] Therefore

[0083] In △OA′1B′1, the length of A′1B′1 can be found using the Law of Cosines:

[0084] |A′1B′1| 2 =|OA′1| 2 +|OB′1| 2 -2|OA′1|·|OB′1|cos|β2-β3|;

[0085] Where, |OA′1|=|OA1|×cosα2=s 21 ·cosα2;|OB′1|=|OB1|×cosα3=s 31 ·cosα3;

[0086] In △OA′1B′1, the measure of ∠OA′1B′1 can be obtained using the Law of Sines:

[0087]

[0088] Therefore

[0089] The angle of retraction γ = ∠OA′1B′1 - ∠OA′B′ = 6.45°.

[0090] Step S2 also includes selecting valid data of the blade in each rotation cycle, which is used to select valid data from all the data of the blade monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2 and the second laser rangefinder P3 in each rotation cycle.

[0091] The valid data refers to all data monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 during the time period from when the wind turbine blade 1 enters the measurement range of P2 to when it leaves the measurement range of P3 in each rotation cycle; or, the valid data refers to all data monitored by the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 during the time period from when the wind turbine blade 1 enters the measurement range of P3 to when it leaves the measurement range of P2 in each rotation cycle.

[0092] The time period from when the fan blade 1 enters the measurement range of P2 to when it leaves the measurement range of P3 includes the state of the fan blade 1 being vertically upward; or, the time period from when the fan blade 1 enters the measurement range of P3 to when it leaves the measurement range of P2 includes the state of the fan blade 1 being vertically upward.

[0093] In the valid data, assume that the data quantities corresponding to the Beidou receiver, the third laser rangefinder P1, the first laser rangefinder P2, and the second laser rangefinder P3 are M0, M1, M2, and M3, respectively; where the following proportional relationship exists: M0 ∝ f0, and ω is the angular velocity of the wind turbine blade 1, f0 is the acquisition frequency of the Beidou receiver, f1 is the acquisition frequency of the third laser rangefinder P1, f2 is the acquisition frequency of the first laser rangefinder P2, and f3 is the acquisition frequency of the second laser rangefinder P3.

[0094] The values ​​of M0, M1, M2, and M3 are all any integers from 2 to 6.

[0095] When using valid data from the BeiDou receiver, the average of M0 data points is taken before use; when using valid data from the third laser rangefinder P1, the average of M1 data points is taken before use; when using valid data from the first laser rangefinder P2, the average of M2 data points is taken before use; when using valid data from the second laser rangefinder P3, the average of M3 data points is taken before use.

[0096] This embodiment provides a method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data. By combining steps S1-S3, the real-time clearance distance of wind turbine blade 1 during wind turbine operation can be obtained, which facilitates timely feedback and control of the wind turbine and ensures the safe operation of the wind turbine.

[0097] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for monitoring the dynamic characteristics of wind turbine blades using BeiDou-integrated laser data, characterized in that, include: Step S1: Conduct aerodynamic experiments on the wind turbine or its scaled-down model in a wind tunnel, or directly measure the operating wind turbine to obtain the deformation structural mechanical characteristic curves of the wind turbine tower (3). Deformation structural mechanical property curves of wind turbine blades (1) ,in, This indicates the displacement of the top of the tower (3). This indicates the displacement of the tower (3) at the lowest plane where the tip of the wind turbine blade (1) sweeps. This indicates the tip displacement of the fan blade (1). The displacement at the bending feature point (5) at the root of the wind turbine blade; ; ; Step S2: Install a Beidou receiver on the top of the nacelle (2) of the wind turbine, and use the spatial positioning function of the Beidou receiver to measure the deformation displacement of the top of the tower (3) during the operation of the wind turbine. ;Depend on The deformation displacement of the tower (3) at the lowest plane of the wind turbine blade (1) during wind turbine operation is derived. ; A third laser rangefinder is installed on the top of the nacelle (2) of the wind turbine. and set The pitch angle is When the fan is stationary, The distance measurement data for the wind turbine blade (1) is as follows: When the fan is running, The distance measurement data for the wind turbine blade (1) is as follows: The deformation displacement at the bending characteristic point (5) at the root of the fan blades during operation is obtained based on trigonometric relationships. ;Depend on The deformation displacement of the tip of the fan blade (1) during fan operation is derived. ; A first laser rangefinder is installed on the top of the nacelle (2) of the wind turbine. Second laser rangefinder and set The pitch angle is , heading angle is ,set up The pitch angle is , heading angle is When the wind turbine blades (1) are open, The laser illuminates the first ranging point on the wind turbine blade (1). The corresponding ranging data is ; The laser illuminates the second ranging point on the wind turbine blade (1). The corresponding ranging data is When the wind turbine blades (1) retract, The laser illuminates the third ranging point on the wind turbine blade (1). The corresponding ranging data is ; The laser illuminates the fourth ranging point on the wind turbine blade (1). The corresponding ranging data is Among them, the first ranging point Second distance measuring point Third distance measuring point and the fourth distance measuring point exist and The projection points on the horizontal plane are respectively , , and The angle of the wind turbine blade (1) after the blade is rotated is the following: It is a straight line With a straight line The included angle between them; Step S3, based on the information obtained in step S2 、 and The data obtained shows the real-time clearance distance of the wind turbine blades (1) during wind turbine operation. ;in, The initial clearance distance set for the wind turbine blades (1).

2. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 1, characterized in that, In step S2, the Beidou receiver and the third laser rangefinder First laser rangefinder Second laser rangefinder All are installed on the top of the cabin (2) and are integrated devices (4).

3. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 2, characterized in that, In step S2, the pitch angle is adjusted. The acquisition process is as follows: With the first laser rangefinder Second laser rangefinder The location of the integrated device (4) is recorded as the origin. ,exist In the middle, the result is obtained using the Law of Cosines. Length: ； in, ; ; exist In the middle, the result is obtained using the law of sines. degree: ; Therefore ; exist In the middle, the result is obtained using the Law of Cosines. Length: ； in, ; ; exist In the middle, the result is obtained using the law of sines. degree: ； Therefore ; Paddle angle .

4. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to any one of claims 1-3, characterized in that, Step S2 also includes selecting valid data from each rotation cycle of the blade for use with the BeiDou receiver and the third laser rangefinder. First laser rangefinder Second laser rangefinder Valid data is selected from all data collected during each rotation cycle of the monitored blades. Among them, the effective data is the wind turbine blade (1) from entry to exit during each rotation cycle. Measurement range to leave The measurement range within the time period is determined by a Beidou receiver and a third laser rangefinder. First laser rangefinder Second laser rangefinder All data monitored; or, valid data is the wind turbine blade (1) from entry to exit point in each rotation cycle. Measurement range to leave The measurement range within the time period is determined by a Beidou receiver and a third laser rangefinder. First laser rangefinder Second laser rangefinder All the data that were monitored.

5. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 4, characterized in that, The fan blades (1) from the inlet Measurement range to leave The measurement range includes the vertically upward state of the fan blades (1) within the time period; Alternatively, the fan blades (1) from the inlet Measurement range to leave The measurement range includes the vertically upward state of the fan blades (1) within the time period.

6. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 5, characterized in that, In the valid data, assuming a corresponding BeiDou receiver and a third laser rangefinder. First laser rangefinder Second laser rangefinder The number of data are respectively , , , Among them, the following proportional relationship exists: , , and , The rotational angular velocity of the fan blade (1) This refers to the sampling frequency of the BeiDou receiver. For the third laser rangefinder The sampling frequency, For the first laser rangefinder The sampling frequency, For the second laser rangefinder The sampling frequency.

7. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 6, characterized in that, , , , The values ​​of are any integers from 2 to 6.

8. The method for monitoring the dynamic characteristics of wind turbine blades using BeiDou fused laser data according to claim 7, characterized in that, When using valid data from a BeiDou receiver, The data were averaged and then used; a third laser rangefinder was used. When valid data is available, The data were averaged and then used; the first laser rangefinder was used. When valid data is available, Use the average of the data points; Using a second laser rangefinder When valid data is available, The average of the data points is then used.

Images