Wind turbine blade dynamic deformation measuring system and method built based on yaw platform

Abstract

The invention relates to a wind turbine blade dynamic deformation measuring system and method built based on a yaw platform. The wind turbine blade dynamic deformation measuring system comprises a wind tunnel, a wind turbine, a yaw control module, a dynamic deformation measuring module and a data processing module. The wind tunnel is used for providing a gas flowing environment; the wind turbine is located right opposite to a wind hole and connected with the yaw control module. The yaw control module is used for driving the wind turbine to rotate as a whole machine and simulating a yaw working state of the wind turbine in actual work; the dynamic deformation measurement module is used for collecting deformation image data of blades in the wind turbine; and the data processing module is used for calculating the deformation amount of the blade according to the deformation image data. According to the invention, the dynamic deformation of the wind turbine blade in the yawing process can be accurately measured in real time by using the motion characteristics of the yawing platform, the measurement precision and efficiency are improved, and the installation and maintenance cost is reduced at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a system and method for measuring the dynamic deformation of a wind turbine blade based on a yaw platform. Background Art

[0002] As a clean and renewable energy source, wind power generation has been widely used and developed around the world. As the core component of the wind power generation system, the performance of wind turbine blades directly affects the efficiency and stability of wind power generation. With the rapid development of wind power technology, the single-unit capacity of wind turbines has continued to increase, and the length of blades has also increased. During operation, the blades are affected by wind loads, gravity and other factors, resulting in dynamic deformation. This deformation not only affects the aerodynamic performance of the wind turbine, but may also cause structural fatigue, thereby affecting the service life and safety of the wind turbine. Therefore, accurate measurement and real-time monitoring of the dynamic deformation of wind turbine blades has become an important means to improve wind turbine performance, extend service life and reduce maintenance costs.

[0003] Due to the ever-changing wind direction in the actual environment, in order to ensure that the wind rotor always faces the incoming wind direction, that is, to keep the angle between the wind rotor axis and the wind direction as small as possible, the wind turbine will adjust the yaw through its own mechanism to maximize the capture of wind energy. Research on the yaw system can optimize its control algorithm and mechanical structure, reduce energy loss caused by inaccurate yaw, and improve the overall power generation efficiency of the wind turbine.

[0004] At present, the deformation of wind turbine blades can be measured by direct measurement. Sensors are installed on the blades to directly measure the deformation of the blades. Static measurement is the main method. A certain static load is applied to the blades, and then the deformation of the blades under the load is measured. However, this method has problems such as complex installation, difficult maintenance, and high cost. It is very different from the actual operation state of the wind turbine, and it is difficult to achieve continuous measurement of the blades during yaw. In addition, an indirect measurement method can be used to indirectly infer the deformation of the blades by measuring other parameters of the wind turbine (such as power, speed, etc.). Although this method is simple and easy, its measurement accuracy is limited. These methods cannot accurately capture the dynamic deformation of the blades in actual operation, which limits the optimization and maintenance of wind turbine performance and is difficult to meet actual operation needs. Summary of the invention

[0005] The purpose of the present invention is to propose a wind turbine blade dynamic deformation measurement system and method based on a yaw platform to solve the problems existing in the above-mentioned prior art, and to be used for real-time and accurate monitoring of the dynamic deformation of wind turbine blades during operation, so as to improve the operating efficiency and safety of the wind turbine.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A wind turbine blade dynamic deformation measurement system based on a yaw platform, comprising: a wind tunnel, a yaw control module, a dynamic deformation measurement module and a data processing module;

[0008] The wind tunnel is used to provide a stable incoming wind speed for the wind turbine;

[0009] The yaw control module is used to drive the wind turbine to perform a rotational motion of the entire machine, simulating the yaw working state of the wind turbine in actual operation;

[0010] The dynamic deformation measurement module is used to collect deformation image data of the blades in the wind turbine;

[0011] The data processing module is used to calculate the deformation amount of the blade according to the deformation image data.

[0012] Optionally, a surface of the wind turbine blade is sprayed with a speckle pattern.

[0013] Optionally, the yaw control module comprises: a yaw platform, a servo motor and a control cabinet;

[0014] The yaw platform is fixed to the ground, and a tower is fixed on the platform;

[0015] The yaw platform is used for displacement in the x direction and the y direction, and the x and y directions are arranged perpendicular to each other;

[0016] The servo motor is used to provide rotational power for the yaw platform;

[0017] The control cabinet is used to collect yaw signals, control the yaw platform, and complete the yaw process.

[0018] Optionally, the dynamic deformation measurement module includes: an image acquisition device, a fixing device, a counterweight device, and a lighting device;

[0019] The image acquisition device is used to acquire the speckle displacement change image on the wind turbine blade;

[0020] The image acquisition unit is fixed on the fixing device, and each fixing device is provided with the counterweight device;

[0021] The lighting device is used to supplement the lighting conditions.

[0022] Optionally, the image acquisition device includes: a first image acquisition device and a second image acquisition device;

[0023] The first image acquisition device and the second image acquisition device are respectively located on the left and right sides of the wind turbine and are respectively fixed on a fixing device.

[0024] A method for measuring dynamic deformation of a wind turbine blade based on a yaw platform, the method comprising:

[0025] Spraying speckle patterns on the surface of wind turbine blades;

[0026] Start the lighting equipment in the dynamic deformation measurement module to provide supplementary lighting for the test site;

[0027] Starting the image acquisition device in the dynamic deformation measurement module to collect the motion trajectory of the speckle image on the blade surface;

[0028] Processing the motion trajectory of the speckle image to calculate the deformation and displacement distribution results of the blade;

[0029] Based on the processing results, the interaction mechanism between the blade and the flow field is analyzed, and the aerodynamic performance and structural strength of the blade are evaluated.

[0030] Optionally, before starting the image acquisition device in the dynamic deformation measurement module, the method further includes:

[0031] The image acquisition device is calibrated using Zhang Zhengyou's calibration method. The calibration plate is lifted up and the target surface of the feature points on the calibration plate is aligned with the image acquisition device.

[0032] The beneficial effects of the present invention are:

[0033] The present invention utilizes the motion characteristics of the yaw platform to achieve real-time and accurate measurement of the dynamic deformation of the blade during the yaw process, thereby improving the measurement accuracy. The measuring device is installed on the yaw platform, which reduces the complexity and maintenance difficulty of directly installing sensors on the blades and reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 This is a schematic structural diagram of a wind turbine blade dynamic deformation measurement system based on a yaw platform according to an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of the structure of a high-speed camera according to an embodiment of the present invention;

[0037] Figure 3Schematic diagrams of deformation of blades in operation according to an embodiment of the present invention; wherein (a) is a schematic diagram of flapping deformation, (b) is a schematic diagram of swing deformation, and (c) is a schematic diagram of torsional deformation;

[0038] Among them, 1. wind tunnel; 2. blades; 3. generator; 4. tower; 5. yaw platform; 6. servo motor; 7. right light source; 8. right camera; 9. voltage-stabilized power supply; 10. left camera; 11. left light source; 12. intelligent control cabinet; 13. workbench; 14. computer; 15. load control equipment; 16. lens; 17. tripod; 18. counterweight module. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] A wind turbine blade dynamic deformation measurement system based on a yaw platform, comprising: a wind tunnel, a wind turbine, a yaw control module, a dynamic deformation measurement module and a data processing module;

[0042] The wind tunnel is used to provide a flow environment for the gas;

[0043] The wind turbine is located directly opposite to the wind tunnel opening and is connected to the yaw control module;

[0044] The yaw control module is used to drive the wind turbine to perform a rotational motion of the entire machine, simulating the yaw working state of the wind turbine in actual operation;

[0045] The dynamic deformation measurement module is used to collect deformation image data of the blades in the wind turbine;

[0046] The data processing module is used to calculate the deformation amount of the blade according to the deformation image data.

[0047] Specifically, in this embodiment, a wind turbine blade dynamic deformation measurement system based on a yaw platform includes: a wind tunnel, a wind turbine, a yaw platform, a dynamic deformation test device, and a data synchronization processing system. The wind turbine is mounted on the yaw platform and is intelligently controlled by a control cabinet to control a servo motor to drive the entire yaw movement.

[0048] Specifically, in the numerical acquisition software, the parameters of the high-speed camera are adjusted, and the running blades are photographed. The photographs are imported into the numerical analysis software, and the displacement of the blades is calculated through the cross-correlation algorithm to obtain the deformation of the blades.

[0049] Specifically, in this embodiment, the wind tunnel comprises: a motor, a stable section, a contraction section, a closed test section and a pressure diffuser section, which ensures that the airflow velocity is stable and uniform after running for a period of time.

[0050] Furthermore, the wind turbine comprises: blades, a tower and a generator;

[0051] The blade surface is sprayed with a speckle pattern;

[0052] The top of the tower is connected to the generator, and the blades are connected to the generator through flanges;

[0053] The wind turbine is driven by the stable incoming wind provided by the wind tunnel to generate electricity.

[0054] Furthermore, the yaw control module comprises: a yaw platform, a servo motor and a control cabinet;

[0055] The yaw platform is fixed to the ground, and the tower is fixed on the platform;

[0056] The yaw platform is used for displacement in the x direction and the y direction, and the x and y directions are arranged perpendicular to each other;

[0057] The servo motor is used to provide rotational power for the yaw platform;

[0058] The control cabinet is used to collect yaw signals, control the yaw platform, and complete the yaw process.

[0059] Specifically, the yaw platform includes: a yaw platform base fixed to the ground, a wind turbine tower fixed above the platform, and while the rotating platform moves, it drives the wind turbine to rotate as a whole, wherein the yaw platform is mainly powered by a servo motor. The wind turbine is installed on the upper part of the yaw platform, which requires the yaw platform to have a good load capacity, and a right-angle yaw platform is selected. The driver and the servo motor are connected through an encoder signal line. The driver transmits motion signals to the servo motor through the encoder signal line to control the movement of the servo motor. At the same time, the servo motor also feeds back motion signals to the driver. The driver compares the command signal issued by the controller and the motion signal fed back by the servo motor to eliminate motion errors and form a closed-loop control system, wherein all encoding modules are installed in the intelligent control cabinet.

[0060] Furthermore, the dynamic deformation measurement module includes: an image acquisition device, a fixing device, a counterweight device, and a lighting device;

[0061] The image acquisition device is used to acquire the speckle displacement change image on the wind turbine blade;

[0062] The image acquisition unit is fixed on the fixing device, and each fixing device is provided with the counterweight device;

[0063] The lighting device is used to supplement the lighting conditions.

[0064] Further, the image acquisition device includes: a first image acquisition device, a second image acquisition device;

[0065] The first image acquisition device and the second image acquisition device are respectively located on the left and right sides of the wind turbine (adjusted according to the display conditions in the actual camera during the experiment), and are respectively fixed on a fixing device.

[0066] Dynamic deformation test device: includes high-resolution camera, light source and image processing software, which is used to capture the deformation image of the blade in the wind field and calculate the displacement and strain of the blade through the algorithm. The speckle image of the blade surface is taken with a high-speed camera, and the deformation and displacement of the blade under different working conditions are calculated through image processing technology.

[0067] The data synchronization processing system is responsible for synchronizing the data acquisition of the DIC and PIV systems, and performing data fusion and analysis to reveal the dynamic response mechanism of the blade fluid-solid coupling.

[0068] Furthermore, in this embodiment, Figure 1 and Figure 2 As shown, a wind turbine blade dynamic deformation measurement system based on a yaw platform is proposed, comprising: a wind tunnel 1, wind turbines 2-4, a yaw platform 5, a dynamic deformation test device and a data synchronization processing system.

[0069] The base of the yaw platform 5 is fixed to the ground, and the wind turbine tower 4 is fixed above the platform. When the rotating platform moves, the wind turbine is driven to rotate as a whole, wherein the yaw platform 5 is mainly powered by the servo motor 6. The yaw platform 5 has displacement functions in the x-direction and the y-direction, and the x- and y-directions are perpendicular to each other. The yaw platform 5 is used to adjust the wind turbine's wind conditions to simulate the yaw working state of the wind turbine in actual operation.

[0070] The yaw platform 5 is mainly powered by the servo motor 6, and the intelligent control cabinet 12 collects the yaw signal, controls the yaw platform 5, and completes the yaw process. The intelligent control cabinet 12 contains all the control modules, and the intelligent control cabinet 12 transmits the motion signal to the servo motor 6 through the signal line to control the movement of the servo motor 6, and the servo motor 6 also feeds back the motion signal.

[0071] The dynamic deformation test device includes: high-speed cameras (left camera 10, right camera 8) and light sources (left light source 11, right light source 7). The high-speed cameras are fixed on a tripod bracket 17, and are both provided with lenses 16. The positions can be adjusted at any time according to other test equipment. Considering the safety of the equipment, a counterweight module 18 is added to the tripod to ensure the stability of the entire object. The light source is fixed on a fixed bracket, and supplementary light is provided according to the sunlight conditions at different times of the day, so that the test field is well lit and the changes in the speckle displacement on the blades can be captured.

[0072] The wind turbine comprises: blades 2, generators 3 and towers 4. The top of the towers 4 is connected to the generators 3, and the blades 2 are connected to the generators 3 through flanges. The wind turbine is driven by the stable incoming wind provided by the wind tunnel 1 to drive the generators to generate electricity.

[0073] The load control device 15 on the workbench 13 is connected to the computer 14 through a wire, and is also connected to the generator through a wire, and the output power of the generator is adjusted and recorded by the load control device 15. All devices are powered by a voltage-stabilized power supply 9.

[0074] All the above test data are collected by computer and analyzed by special software.

[0075] This embodiment also proposes a method for measuring the dynamic deformation of a wind turbine blade based on a yaw platform, including:

[0076] Prepare a wind turbine and spray a speckle pattern on the surface of the blade;

[0077] Start the lighting equipment in the dynamic deformation measurement module to provide supplementary lighting for the test site;

[0078] Starting the image acquisition device in the dynamic deformation measurement module to collect the motion trajectory of the speckle image on the blade surface;

[0079] Processing the motion trajectory of the speckle image to calculate the deformation and displacement distribution results of the blade;

[0080] Based on the processing results, the interaction mechanism between the blade and the flow field is analyzed, and the aerodynamic performance and structural strength of the blade are evaluated.

[0081] Furthermore, before starting the image acquisition device in the dynamic deformation measurement module, the method further includes:

[0082] The image acquisition device is calibrated using Zhang Zhengyou's calibration method. The calibration plate is lifted up and the target surface of the feature points on the calibration plate is aligned with the image acquisition device.

[0083] Specifically, in this embodiment, a method for measuring the dynamic deformation of a wind turbine blade based on a yaw platform includes the following steps:

[0084] Preparation stage: blade 2 is manufactured and a speckle pattern is sprayed on the surface of blade 2. When testing, the wind turbine faces wind tunnel 1 and appropriate parameters such as wind speed and wind direction are set in the flow field.

[0085] Measurement phase: Start the left light source 11 and the right light source 8 in the dynamic deformation test device to fill in the light for the entire test site so that the brightness of the entire test site meets the test requirements. Then turn on the left camera 10 and the right camera 8, adjust the camera parameters, so that the camera can capture the changes in the blades, shoot the motion trajectory of the speckle image on the blade surface, and ensure high precision. First, calibrate the dynamic deformation test device. Use Zhang Zhengyou's calibration method to calibrate the dual-camera system. Hold up the calibration plate and align the target surface of the characteristic points on the calibration plate with the camera to ensure that a clear image is captured. Secondly, the servo motor 6 is connected to the intelligent control cabinet 12 through a signal line. The position and speed information of the motor 6 during operation is fed back to the intelligent control cabinet 12 through the shaft encoder at the tail of the motor. The intelligent control cabinet 12 feeds back the obtained information to the control computer 14. The operating status of the motor and the yaw of the wind turbine can be intuitively viewed through the monitoring software.

[0086] Data processing stage: Use the data acquisition and analysis system to process the captured images and calculate the deformation and displacement distribution of the blades.

[0087] Result analysis stage: Analyze the interaction mechanism between the blade and the flow field based on the processing results, and evaluate the aerodynamic performance and structural strength of the blade.

[0088] This embodiment utilizes the motion characteristics of the yaw platform to achieve real-time and accurate measurement of the dynamic deformation of the blades during the yaw process, thereby improving the measurement accuracy. The measuring device is installed on the yaw platform, which reduces the complexity and maintenance difficulty of installing sensors directly on the blades, thereby reducing costs. Six-degree-of-freedom changes generally refer to the fact that an object can translate along three coordinate axes in space (X, Y, and Z directions) and rotate around these three coordinate axes (pitch, yaw, and roll). Wind turbines are in complex and diverse environments, and there are many situations where they are not in line with the wind, so their posture is often adjusted during operation. The rotating blades are subject to loads and deform. In order to accurately monitor the deformation of wind turbine blades during actual operation, it is necessary to consider the changes in the six degrees of freedom of the blades. Unlike the prior art, this embodiment can effectively observe small deformations of the blades in six degrees of freedom, such as Figure 3As shown in (a) to (c). The blades of a wind turbine are usually designed to have a certain degree of elasticity so that they can perform efficient energy conversion under the action of wind. When the wind acts on the blades, the blades will bend along the wind direction. This bending is elastic, which means that the blades can return to their original shape after the wind decreases or disappears. In addition to bending deformation, the blades may also undergo torsional deformation. This is because the wind force not only acts on the vertical cross-section of the blade, but also generates different torques in the span direction of the blade (that is, the length direction of the blade), causing the blades to twist during rotation. When observing the end of the blade, you may visually feel that the blades seem to "become longer" or "shortened". In addition, the wind turbine speed change threshold in this patented technology is large, and a higher speed can be achieved. At the same time, the camera has a high accuracy. The debugging methods of the two are combined to achieve the measurement of unexpected operating modes such as dynamic stall and brake failure, and the analysis of multi-scenario operating conditions can be achieved.

[0089] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A wind turbine blade dynamic deformation measurement system based on a yaw platform, characterized in that: include: Wind tunnel, yaw control module, dynamic deformation measurement module and data processing module; The wind tunnel is used to provide a stable incoming wind speed for the wind turbine; The yaw control module is used to drive the wind turbine to perform a rotational motion of the entire machine, simulating the yaw working state of the wind turbine in actual operation; The dynamic deformation measurement module is used to collect deformation image data of the blades in the wind turbine; The data processing module is used to calculate the deformation amount of the blade according to the deformation image data.

2. The wind turbine blade dynamic deformation measurement system based on the yaw platform according to claim 1 is characterized in that: The blade surface of the wind turbine is sprayed with a speckle pattern.

3. The wind turbine blade dynamic deformation measurement system based on the yaw platform according to claim 2 is characterized in that: The yaw control module includes: a yaw platform, a servo motor and a control cabinet; The yaw platform is fixed to the ground, and a tower is fixed on the platform; The yaw platform is used for displacement in the x direction and the y direction, and the x and y directions are arranged perpendicular to each other; The servo motor is used to provide rotational power for the yaw platform; The control cabinet is used to collect yaw signals, control the yaw platform, and complete the yaw process.

4. The wind turbine blade dynamic deformation measurement system based on the yaw platform according to claim 2 is characterized in that: The dynamic deformation measurement module includes: an image acquisition device, a fixing device, a counterweight device, and a lighting device; The image acquisition device is used to acquire the speckle displacement change image on the wind turbine blade; The image acquisition unit is fixed on the fixing device, and each fixing device is provided with the counterweight device; The lighting device is used to supplement the lighting conditions.

5. The wind turbine blade dynamic deformation measurement system based on the yaw platform according to claim 4 is characterized in that: The image acquisition device comprises: a first image acquisition device and a second image acquisition device; The first image acquisition device and the second image acquisition device are respectively located on the left and right sides of the wind turbine and are respectively fixed on a fixing device.

6. A method for measuring the dynamic deformation of a wind turbine blade based on a yaw platform, characterized in that: The method for implementing the wind turbine blade dynamic deformation measurement system based on the yaw platform as claimed in any one of claims 1 to 5 comprises: Spraying speckle patterns on the surface of wind turbine blades; Start the lighting equipment in the dynamic deformation measurement module to provide supplementary lighting for the test site; Starting the image acquisition device in the dynamic deformation measurement module to collect the motion trajectory of the speckle image on the blade surface; Processing the motion trajectory of the speckle image to calculate the deformation and displacement distribution results of the blade; Based on the processing results, the interaction mechanism between the blade and the flow field is analyzed, and the aerodynamic performance and structural strength of the blade are evaluated.

7. The method for measuring dynamic deformation of wind turbine blades based on a yaw platform according to claim 6 is characterized in that: Before starting the image acquisition device in the dynamic deformation measurement module, the following steps are also included: The image acquisition device is calibrated using Zhang Zhengyou's calibration method. The calibration plate is lifted up and the target surface of the feature points on the calibration plate is aligned with the image acquisition device.

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