An active control system and method for wind turbine blades for wind power generation

Abstract

The application relates to the field of wind power generation, and discloses an active control system and method for wind turbine blades used in wind power generation. The active control system for wind turbine blades used in wind power generation comprises an airfoil control system, and the main feature is that the blade comprises a first group of movable blade segments and a second group of movable blade segments, which are respectively located on the pressure surface and the suction surface of the blade and are connected through hinges. The blade airfoil adjusting mechanism comprises a web, a rigid connecting piece at the subsequent end point and a driving device, and is used for dynamically adjusting the airfoil curvature of the blade. A wind speed and direction sensor monitors the wind speed and direction in real time, and sends the monitoring result to an airfoil controller. The airfoil controller controls the blade airfoil adjusting mechanism according to the monitoring result, so that the airfoil curvature of the wind turbine blade is adjusted.

Description

Technical Field

[0001] This invention relates to the field of wind power generation, specifically to an active control system and method for wind turbine blades used in wind power generation. Background Technology

[0002] A wind turbine is a device that uses wind energy to generate electricity. Its working principle is based on the conversion of the wind's kinetic energy into mechanical energy, and then into electrical energy. The advantages of wind turbines include being clean, renewable, and having low carbon emissions.

[0003] In existing technologies, the control of wind turbine blades mainly relies on passive control technologies, such as fixed blade geometry design, or adjusting the blade's windward attitude by yaw operation of the wind turbine and pitch angle operation of the blade. However, passive control systems have slow response speeds and cannot adapt to rapidly changing wind speeds and directions in a timely manner. Furthermore, fixed geometry designs cannot adapt to all wind conditions, leading to excessive blade bending and vibration caused by bending. This affects the structural stability and power generation efficiency of the entire generator set, while also accelerating blade fatigue damage and even failure, shortening its service life. Moreover, the high maintenance cost of blades results in significant economic losses. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an active control system and method for wind turbine blades used in wind power generation. This solves the problem that the slow response speed of existing passive control systems leads to excessive bending of the blades and vibration fatigue damage caused by bending, thereby affecting the structural stability and power generation efficiency of the generator set, shortening its service life, and causing significant economic losses.

[0005] Firstly, to achieve the above objectives, the present invention provides the following technical solution: an active control system for wind turbine blades used in wind power generation, the active control system comprising an airfoil control system, the airfoil control system comprising:

[0006] A wind turbine blade includes: a first group of movable blade segments and a second group of movable blade segments; the first group of movable blade segments is located on the pressure surface of the blade, and its movable blade segments are connected sequentially by hinges; the second group of movable blade segments is located on the suction surface of the blade, and its movable blade segments are connected sequentially by hinges; one end of the first group of movable blade segments and the second group of movable blade segments are respectively connected to the trailing edge of the blade to form a movable adjustment part of the trailing edge of the blade; the other end of the first group of movable blade segments is hinged to the upper main beam of the blade, and the other end of the second group of movable blade segments is hinged to the lower main beam of the blade;

[0007] A blade airfoil adjustment mechanism is used to dynamically adjust the airfoil curvature of a wind turbine blade. The blade airfoil adjustment mechanism includes: a rigid connector connected to the web and the subsequent end of the blade; a drive device fixed to the rigid connector, the drive device being telescopically connected to a first group of movable blade segments and / or a second group of movable blade segments, for independently or collaboratively telescopically extending, moving, or rotating the movable blade segments.

[0008] Wind speed and direction sensors are used to monitor wind speed and direction in real time and send the monitoring results to the airfoil controller;

[0009] An airfoil controller, located at the blade root, is used to receive the monitoring results of wind speed and wind direction from the wind speed and wind direction sensors, and to control the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades based on the monitoring results.

[0010] In some possible implementations, the drive device is specifically used to: independently control the extension, movement, or rotation of each set of movable blade segments under the control of the airfoil controller; coordinately adjust the position and / or angle of multiple movable blade segments; the drive device includes a hydraulic servo drive device, which changes the curvature of the blade pressure surface or suction surface by means of the extension and retraction of the drive end.

[0011] In some possible implementations, the airfoil controller is used to receive external environmental state information and blade state information, calculate the optimal blade curvature adjustment scheme under the condition of limited segmentation of the blade pressure surface and suction surface, and control the drive device to make corresponding adjustments according to the optimal blade curvature adjustment scheme; the external environmental state information includes the wind speed and wind direction at the height of the wind turbine; the blade state information includes: feathering state, standby state, or operating state, wherein the operating state specifically refers to the current angle of attack of the blade.

[0012] In some possible implementations, an eddy current control system is also included, which includes an eddy current generator and an eddy current controller;

[0013] The eddy current generator, located near the blade tip, specifically includes:

[0014] Multiple stomata are used to adjust the airflow near the blade tip;

[0015] Solenoid valves are used to independently control the opening and closing of air vents;

[0016] Pressure sensors are installed in the pipes on both sides of the air vent to detect the dynamic pressure of the local airflow and feed the pressure signal back to the eddy current controller.

[0017] An annular cavity has multiple radial channels inside, one of which is fixedly connected to the pressure sensor. Multiple air holes are provided on both sides of the radial channels inside the annular cavity.

[0018] In some possible implementations, the active control system for a wind turbine blade for wind power generation further includes an eddy current control system, which includes an eddy current generator and an eddy current controller.

[0019] The eddy current generator, located near the blade tip, specifically includes:

[0020] An annular cavity has a first end face and a second end face. Between the first end face and the second end face, there are multiple axial channels extending along the blade length direction and distributed on the pressure surface and suction surface of the blade. Multiple air holes are respectively provided on the first end face and the second end face. Each axial channel is connected to a set of air holes provided on the first end face and the second end face.

[0021] The central manifold is located in the middle of the interior of the annular cavity and is connected to multiple axial pipes. The central manifold is also connected to the internal space of the blade. It is used to collect external airflow from multiple axial pipes and introduce it into the interior of the blade, or to distribute airflow generated from the air source inside the blade to multiple axial pipes for output to the outside of the blade.

[0022] Multiple solenoid valves, each of which is disposed near one or more air holes, are used to open or close one or more nearby air holes or adjust the opening area of ​​one or more nearby air holes according to the control command of the eddy current controller.

[0023] Multiple pressure sensors are respectively installed in multiple axial pipes to detect the pressure of the airflow and feed the pressure signal back to the eddy current controller;

[0024] The eddy current controller is used to control the working state of one or more corresponding solenoid valves, or to control the working state of the air source inside the blade, based on the pressure signal in the first set of axial pipes located on the pressure surface of the blade and the pressure signal in the second set of axial pipes located on the suction surface of the blade.

[0025] In some possible implementations, the active control system of the wind turbine blade further includes a load control system, the load control system comprising:

[0026] Strain gauges and accelerometers are installed at key locations on the blade surface and inside to monitor the blade's bending and vibration data in real time.

[0027] A load controller is used to calculate the real-time load on each part of the blade based on the bending and vibration data of the blade fed back by the strain gauges and accelerometers.

[0028] The overload warning module is used to optimize the airfoil control parameters and / or eddy current control parameters of the blade or send a shutdown signal when the real-time load on the blade is detected to be greater than the preset load threshold.

[0029] Optimize the airfoil control parameters of the blades, specifically by changing the blade angle of attack or adjusting the airfoil curvature to reduce lift;

[0030] Eddy current control parameters specifically include: the opening degree of the solenoid valve.

[0031] In some possible implementations, the strain gauges and accelerometers are arranged at the root, middle and tip of the blade to comprehensively monitor the bending and vibration of the blade in all directions.

[0032] The blade bending and blade-induced vibration suppression module is used to control the extension and retraction of the drive end of the drive device based on the detection information of the strain gauge and accelerometer, thereby changing the curvature of the pressure surface and suction surface of the blade to suppress blade bending and blade-induced vibration.

[0033] The overload warning module is specifically used to evaluate in real time whether the load on the blade exceeds the design threshold based on the real-time load provided by the load controller; once an overload is detected, the blade airfoil control parameters are automatically adjusted; if the load is still too high after adjustment, the overload warning module will trigger an emergency shutdown procedure to stop the wind turbine from operating.

[0034] Secondly, a control method for an active control system of a wind turbine blade for wind power generation is provided. According to the aforementioned active control system for a wind turbine blade, it includes the following steps:

[0035] S1: Real-time monitoring of wind speed and direction via wind speed and direction sensors, and sending the monitoring results to the airfoil controller;

[0036] S2: The airfoil controller receives the monitoring results of wind speed and wind direction from the wind speed and wind direction sensors, and controls the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades according to the monitoring results.

[0037] In some possible implementations, the method further includes the following steps:

[0038] S3: Adjust the airflow state near the blade tip by setting a vortex generator near the blade tip. The vortex generator includes multiple air holes and electromagnetic valves for independently controlling the opening and closing of the air holes.

[0039] S4: The dynamic pressure of the local airflow is detected by pressure sensors installed in the pipes on both sides of the air hole, and the pressure signal is fed back to the eddy current controller, which controls the working state of the multiple solenoid valves.

[0040] In some possible implementations, the method further includes the following steps:

[0041] S5: Real-time monitoring of blade bending and vibration data using strain gauges and accelerometers installed at key locations on the blade surface and inside;

[0042] S6: The load controller calculates the real-time load on each part of the blade based on the blade bending and vibration data fed back by the strain gauges and accelerometers;

[0043] S7: When the overload warning module detects that the real-time load on the blade is greater than the preset load threshold, it optimizes the airfoil control parameters and / or eddy current control parameters of the blade, or sends a shutdown signal when necessary; wherein, optimizing the airfoil control parameters of the blade includes changing the blade angle of attack or adjusting the airfoil curvature to reduce lift; the eddy current control parameters include the opening degree of the solenoid valve.

[0044] In some possible implementations, in step S7, the overload warning module is specifically used to evaluate in real time whether the load borne by the blade exceeds the design threshold based on the real-time load data provided by the load controller; once an overload is detected, the parameters of the blade airfoil control system are automatically adjusted; if the load is still too high after adjustment, the overload warning module will trigger an emergency shutdown procedure to stop the wind turbine from operating.

[0045] This invention provides an active control system and method for wind turbine blades, which has the following beneficial effects:

[0046] This invention, through an active or passive control system and its wind load reduction method, can quickly respond to changes in wind speed and direction, adjust the shape and attitude of the blades, and reduce the bending and vibration of the blade tips through an eddy current controller, thereby improving the stability and efficiency of the generator.

[0047] This invention uses a microcontroller to control the variable curvature blade system and eddy current controller in a timely manner based on information transmitted from strain gauges, accelerometers, and wind speed and direction sensors. This reduces excessive bending of the blades and vibration fatigue damage caused by bending, thereby reducing blade fatigue damage, increasing blade service life, shortening blade maintenance cycles, and consequently reducing significant economic losses. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the cross-section of a blade and the working state of its internal airfoil control system according to an embodiment of the present invention. Figure 1 ;

[0049] Figure 2 This is a schematic diagram of the cross-section of a blade and the working state of its internal airfoil control system according to an embodiment of the present invention. Figure 2 ;

[0050] Figure 3 This is a schematic diagram of the cross-section of a blade and the working state of its internal airfoil control system according to an embodiment of the present invention. Figure 3 ;

[0051] Figure 4 This shows the structure of a blade and its cross-section ABCD.

[0052] Figure 5 This is a framework diagram of the airfoil control system in an embodiment of the present invention;

[0053] Figure 6 This is a structural framework diagram of the active control system for wind turbine blades used in wind power generation, according to an embodiment of the present invention.

[0054] Figure 7 This is a schematic diagram of the eddy current control system of the active control system for wind turbine blades used in wind power generation, according to an embodiment of the present invention. Figure 1 ;

[0055] Figure 8 This is a schematic diagram of the eddy current generator in the active control system of wind turbine blades for wind power generation, according to an embodiment of the present invention. Figure 1 ;

[0056] Figure 9 This is a schematic diagram of the eddy current generator in the active control system of wind turbine blades for wind power generation, according to an embodiment of the present invention. Figure 2 ;

[0057] Figure 10 This is a flowchart of the control method according to an embodiment of the present invention.

[0058] Explanation of icon numbers:

[0059] 210. Eddy current generator;

[0060] 220. Eddy current controller;

[0061] 211. Annular cavity;

[0062] 212. Stomata;

[0063] 213. Solenoid valve;

[0064] 214. Pressure sensor;

[0065] 215. Radial pipe. Detailed Implementation

[0066] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] Example 1

[0068] This invention provides an active control system for wind turbine blades used in wind power generation, which aims to improve the stability of the wind turbine blades and tower support structure, increase the efficiency of the wind turbine, extend its service life, and avoid major economic losses such as blade breakage and tower collapse.

[0069] Please see Figures 1 to 5 An active control system for wind turbine blades used in wind power generation, comprising an airfoil control system, the airfoil control system including:

[0070] The wind turbine blade comprises: a first set of movable blade segments and a second set of movable blade segments; the first set of movable blade segments (corresponding to...) Figure 1 The CP, PE, and EG segments are located on the pressure surface of the blade, and the movable blade segments contained therein are connected sequentially by hinges; the second group of movable blade segments (corresponding to...) Figure 1 The CQ, QF, and FH segments are located on the suction surface of the blade, and the movable blade segments contained therein are connected sequentially by hinges; one end of the first group of movable blade segments and one end of the second group of movable blade segments are respectively connected to the trailing edge of the blade (corresponding to...). Figure 1 Connecting to point C in the diagram, forming the movable adjustment section of the blade's trailing edge; the other end of the first set of movable blade segments is connected to the upper main beam of the blade (corresponding to...). Figure 1 The main beam at the location of GD is hinged, and the other end of the second set of movable segments is connected to the lower main beam of the blade (corresponding to...). Figure 1 The main beam at the location of HB is hinged; Figure 1 The A in the middle represents the leading edge of the blade.

[0071] A blade airfoil adjustment mechanism is used to dynamically adjust the airfoil curvature of wind turbine blades; the blade airfoil adjustment mechanism includes: a web connected to the blade (corresponding to...). Figure 1 The rigid connection between the BD segment and the subsequent endpoints; two drive units (corresponding to Figure 1 The boxes near O1 and O2 in the diagram), the drive device can be a hydraulic drive device, fixed to a rigid connecting member (corresponding to...). Figure 1On the straight line where CM is located, the drive unit is telescopically connected to the first group of movable blade segments and / or the second group of movable blade segments, for independently or collaboratively extending, moving, or rotating the movable blade segments; the drive unit can be implemented through a hydraulic servo control system. Figure 1 In this diagram, O1 and O2 represent two driving devices. The first driving ends of driving devices O1 and O2 are connected to points P and E, respectively, at the hinge of the pressure surface. The second driving ends of driving devices O1 and O2 are connected to points Q and F, respectively, at the hinge of the suction surface. The corresponding driving ends of the pressure or suction surfaces of each driving device O1 and O2 can be controlled independently. On the pressure surface, CP and PE have a certain length of overlapping section at the hinge point P. This overlap can be a top-to-bottom overlapping, with either CP covering a portion of the PE section or vice versa. Similarly, PE covers a certain length of the EG section, or vice versa, ensuring no gaps are created when the blade airfoil curvature changes. On the suction surface, CQ and QF sections also have a certain degree of overlap, as do QF and FH sections. At the hinge points corresponding to P, E, Q, and F, there are canvas dustproof devices to prevent dust, wind, rain, and snow from entering the blade cavity through P, E, Q, and F. This connection makes the pressure surface CPEG segment more convex (smaller radius of curvature) or more straight (larger radius of curvature). Similarly, the suction surfaces C, Q, F, and H can also become more convex towards the pressure surface, or... Figure 1 As shown, C, Q, F, and H become more convex downwards. This means the pressure surface CPEG will have three distinct characteristic positions: first, the middle position, which is the original design position before airfoil adjustment; second, the pressure surface becomes more convex upwards; and third, the pressure surface CPEG moves closer to the drive devices O1 and O2, causing the drive rod to retract. The suction surface CQFH also has three distinct characteristic positions: first, the original position; second, the downward-moving position, where CQFH shifts downwards and its curvature becomes more convex; and third, the upward-moving position, where it moves closer to the drive devices O1 and O2.

[0072] Wind speed and direction sensors are used to monitor the wind speed and direction of the upwind flow in real time and send the monitoring results to the airfoil controller.

[0073] An airfoil controller, located at, but not limited to, the blade root, receives wind speed and direction monitoring results from wind speed and direction sensors via wired or wireless means, and controls the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades based on the monitoring results. This helps to increase the efficiency of wind turbine in absorbing wind energy at low wind speeds, suppress the degree of blade bending caused by wind turbulence, and suppress the bending vibration of the wind turbine under varying wind speeds.

[0074] See Figure 2In part (4), to achieve higher wind energy utilization efficiency and increase output at low wind speeds, the airfoil controller and drive devices O1 and O2 are used to extend P and E at the blade pressure surface hinge. That is, the pressure surface drive ends of drive devices O1 and O2 extend upward, the extension section increases, P and E move upward, the overlap or coverage of the pressure surface CP and PE sections decreases, CPEG becomes more convex, the radius of curvature decreases, and the angle of attack control of the wind turbine is increased. At the same time, QF remains unchanged.

[0075] See Figure 2 In (5), to increase the output, hinge points P and E remain unchanged, and hinge points Q and F are controlled to rise. The extended ends of drive devices O1 and O2 are shortened, and hinge points Q and F move upward. This, combined with the wind turbine angle of attack control, obtains the maximum output at the current wind speed. This makes the curvature of CQFH more convex upward (the radius of curvature becomes smaller).

[0076] See Figure 2 In step (6), when increased blade bending vibration is detected, the airfoil controller, with the help of drive devices O1 and O2, lengthens the drive ends of drive devices O1 and O2, causing hinge points P and E to move upward, or simultaneously causes drive devices O1 and O2 to control the drive ends of the suction surface to contract, causing hinge points Q and F to move upward. The extension of hinge points P and E and the contraction of hinge points Q and F are controlled according to the recovery of blade bending and / or vibration levels. This links blade curvature control with blade bending vibration. The airfoil controller, with the help of sensors and drive devices, changes the degree of blade bending, suppressing blade bending vibration, and achieving active control of blade curvature to suppress blade bending and bending vibration.

[0077] See Figure 3 In (7), when the wind speed of the external wind field gradually increases, even exceeding the rated wind speed, the airfoil controller uses drive devices O1 and O2 to move the hinge points Q and F corresponding to the drive end facing the suction surface downward, i.e., the extension section becomes longer. If vibration occurs, the extension ends of drive devices O1 and O2 corresponding to hinge points P and E can be controlled to grow and extend upward. The degree of extension is determined based on the feedback from stress strain sensors and / or vibration sensors. If the vibration level decreases to within the target value, the extension of drive devices O1 and O2 is stopped. By controlling the extension amount of the drive device extension end, the curvature of the entire pressure surface or suction surface is changed, thus completing the bending vibration caused by the force on the blades under variable wind speed conditions that fixed airfoil wind turbines cannot adapt to, as well as the active control of the degree of bending.

[0078] See Figure 3In (8), after the wind speed is detected to be continuously increasing and maintained, it is necessary to increase the output of the wind turbine to obtain a greater generator output power. At this time, the driving devices O1 and O2 can be used to make the pressure surface PE more convex and the radius of curvature smaller. That is, under the command of the airfoil controller, the driving devices O1 and O2 increase the length of the driving end of the pressure surface. Alternatively, while increasing the extension length of the driving end of the pressure surface of the driving devices O1 and O2, the extension length of the driving end of the suction surface of the driving devices O1 and O2 can be reduced. The entire pressure surface becomes more convex and the entire suction surface becomes more concave, that is, CQFH becomes more convex in the direction of the pressure surface.

[0079] In some embodiments, drive devices O1 and O2 are specifically used to independently control the extension, movement, or rotation of each set of movable blade segments under the control of the airfoil controller; and to coordinately adjust the position and / or angle of multiple movable blade segments to optimize the aerodynamic performance and power generation efficiency of the blades. The drive device includes a hydraulic servo drive device, which changes the curvature of the pressure surface or suction surface of the blade by means of the extension and retraction of the drive end.

[0080] Specifically, the independent control of the extension, movement, or rotation of each set of movable blade segments describes the system's drive mechanism's ability to individually control each set of movable segments. During wind turbine operation, each set of blades can independently extend, move, or rotate as needed. This design allows each set of blades to be individually adjusted according to wind speed, wind direction, and other environmental factors, thereby maximizing its efficiency and adaptability.

[0081] Specifically, the coordinated adjustment of the position and / or angle of multiple movable blade segments indicates that the system can control individual blade segments while also considering the interaction and coordination between multiple segments as a whole, thereby achieving more precise control and optimizing overall aerodynamic performance. Coordinated adjustment can improve the impeller's response speed and efficiency to wind changes, especially when wind direction or speed changes rapidly. By coordinating the simultaneous adjustment of multiple segments, it can adapt to environmental changes more quickly, maintaining or improving power generation efficiency.

[0082] In some embodiments, the airfoil controller is used to receive external environmental state information and blade state information, calculate the optimal blade curvature adjustment scheme under the condition of finite segmentation of the blade pressure surface and suction surface, and control the drive device to make corresponding adjustments according to the optimal blade curvature adjustment scheme; the external environmental state information includes the wind speed and wind direction at the height of the wind turbine; the blade state information includes: feathering state, standby state or working state, and the working state specifically refers to the current angle of attack of the blade.

[0083] Specifically, the following is the detailed process for calculating the optimal blade curvature adjustment scheme:

[0084] Step 1: Obtain external environment status information and blade status information.

[0085] The airfoil controller first acquires information about the external environment and the blades. The external environment information includes wind speed and direction at the turbine's altitude, which can be monitored in real-time by wind speed and direction sensors and transmitted to the airfoil controller. Blade status information includes feathering status, standby status, or operating status, with the operating status specifically referring to the current angle of attack of the blade. This status information can be acquired through sensors on the blades or the wind turbine's control system.

[0086] Step 2: Establish a database of blade aerodynamic performance.

[0087] To calculate the optimal blade curvature adjustment scheme, the airfoil controller requires a blade aerodynamic performance database. This database contains aerodynamic performance data for the blade under different wind speeds, wind directions, angles of attack, and blade curvatures, such as lift coefficient and drag coefficient. This data can be obtained through wind tunnel tests, numerical simulations, or actual measurements and stored in the airfoil controller's memory.

[0088] Step 3: Determine the optimization objective.

[0089] Airfoil controllers need to define optimization objectives, i.e., how to adjust blade curvature to achieve optimal performance given external environmental and blade conditions. In this embodiment, optimization objectives include maximizing wind energy capture efficiency, minimizing load fluctuations, and reducing noise. The selection of optimization objectives depends on the specific application and design requirements of the wind turbine.

[0090] Step 4: Establish an optimization model.

[0091] Based on the optimization objective, the airfoil controller establishes an optimization model. This model describes the mathematical relationship between blade curvature and the optimization objective, and considers various constraints, such as structural strength limitations of the blade and the range of motion of movable blade segments. The optimization model can be a linear or nonlinear mathematical programming problem, or it can be a heuristic algorithm or an intelligent optimization algorithm.

[0092] Step 5: Solve the optimization model.

[0093] The airfoil controller uses an appropriate optimization algorithm to solve the optimization model and obtain the optimal blade curvature adjustment scheme. Optimization algorithms can include gradient descent, Newton's method, genetic algorithms, particle swarm optimization, etc. During the solution process, the airfoil controller queries relevant aerodynamic data from the blade aerodynamic performance database based on the current external environment and blade condition, and substitutes this data into the optimization model for calculation.

[0094] Step 6: Control the drive device to adjust the blade curvature.

[0095] Once the optimal blade curvature adjustment scheme is obtained, the airfoil controller will control the drive unit to adjust the movable blade segments accordingly. The drive unit can independently control the extension, movement, or rotation of each set of movable blade segments, or it can coordinately adjust the position and / or angle of multiple movable blade segments, thereby achieving precise control of the blade curvature. This includes adjusting the first set of movable segments (CP, PE, EG segments) on the pressure surface and the second set of movable segments (CQ, QF, FH segments) on the suction surface.

[0096] Step 7: Real-time monitoring and feedback control.

[0097] During the adjustment of blade curvature, the airfoil controller continuously monitors changes in the external environment and blade condition, and updates and solves the optimization model based on real-time data. This real-time monitoring and feedback control ensures that the blade curvature remains at its optimal state, adapting to constantly changing wind and operating conditions.

[0098] Through the above steps, the airfoil controller can calculate the optimal blade curvature adjustment scheme under the condition of limited segmentation of the pressure and suction surfaces of the wind turbine blades based on the external environmental status information and blade status information, and control the drive device to make corresponding adjustments to the blades, thereby realizing the safe and efficient operation of the wind turbine and optimized load control.

[0099] Specifically, in step 4, establishing the optimization model, the airfoil controller builds an optimization model based on the optimization objective. The optimization model describes the mathematical relationship between blade curvature and the optimization objective, and considers various constraints. Here are a few examples of optimization models:

[0100] Example 1: Maximize wind energy capture efficiency.

[0101] The optimization objective is to maximize the wind energy capture efficiency of the wind turbine, i.e., to maximize the ratio of lift coefficient to drag coefficient (L / D) of the blades. The optimization variable is the curvature variation of each blade segment. The constraints are the structural strength limitations of the blades and the range of motion of the movable blade segments.

[0102] Optimization model:

[0103] Maximize L / D, where L / D represents the ratio of lift coefficient to drag coefficient, used to describe the wind turbine's wind energy capture efficiency.

[0104] The condition is satisfied that |ΔCurvature_i|≤MaxCurvatureChange_i, where i=1,2,...,n. ΔCurvature_i represents the curvature change of each segment of the blade, and i represents a specific segment of the blade.

[0105] |Stress_j|≤MaxStress_j, j=1,2,...,m. Stress_j represents the structural stress of the blade, and j represents a specific part of the blade.

[0106] Example 2: Minimize load fluctuations.

[0107] The optimization objective is to minimize the load fluctuation experienced by the blade during rotation, i.e., to minimize the standard deviation of the load. The optimization variable is the curvature variation of each blade segment. The constraints are the structural strength limitations of the blade and the range of motion of the movable blade segments.

[0108] Optimization model:

[0109] Minimize Std(Load), where Std(Load) represents the standard deviation of the load and is used to describe the magnitude of load fluctuation.

[0110] The condition is satisfied that |ΔCurvature_i|≤MaxCurvatureChange_i, where i=1,2,...,n. MaxCurvatureChange_i represents the maximum limit value for the change in curvature of each segment of the blade.

[0111] |Stress_j|≤MaxStress_j, j=1,2,...,m. MaxStress_j represents the maximum limit value of the stress on the blade structure.

[0112] Example 3: Reduce noise.

[0113] The optimization objective is to minimize the noise generated by the blade during rotation. The optimization variable is the change in curvature of each blade segment. The constraints are the structural strength limit of the blade, the range of motion of the movable blade segments, and the upper limit of the noise level.

[0114] Optimization model:

[0115] Minimize Noise, where Noise refers to the level of noise generated by the blades during rotation.

[0116] It satisfies |ΔCurvature_i|≤MaxCurvatureChange_i, i=1,2,...,n.

[0117] |Stress_j|≤MaxStress_j, j=1,2,...,m. Stress_j represents the structural stress of the blade, j represents a specific part of the blade, and MaxStress_j represents the maximum limit value of the structural stress of the blade.

[0118] Noise ≤ MaxNoiseLevel. MaxNoiseLevel represents the upper limit of the noise level.

[0119] In step 5, after establishing the optimization model, the airfoil controller uses an appropriate optimization algorithm to solve the model and obtain the optimal blade curvature adjustment scheme under the condition of finite segmentation of the wind turbine blade pressure and suction surfaces. The following are examples of several optimization algorithms:

[0120] Example 1: Gradient Descent. Gradient descent is a first-order optimization algorithm that finds a local optimum by iteratively searching along the opposite direction of the gradient of the objective function. The algorithm steps include: (1) Selecting the initial blade curvature, setting the learning rate and the number of iterations. (2) Calculating the objective function value and gradient under the current blade curvature. (3) Updating the blade curvature based on the gradient and the learning rate. Repeat steps (2)-(3) until the maximum number of iterations is reached or the convergence condition is met.

[0121] Example 2: Genetic Algorithm. A genetic algorithm is a heuristic optimization algorithm that searches for the optimal solution by simulating natural selection and genetic processes. The algorithm steps include: (1) Randomly generating a set of initial leaf curvatures as a population. (2) Evaluating the fitness (objective function value) of each individual (leaf curvature). (3) Generating a new population through selection, crossover, and mutation operations. Repeating steps (2)-(3) until the maximum number of iterations is reached or the convergence condition is met.

[0122] Example 3: Particle Swarm Optimization (PSO) Algorithm. PSO is a swarm optimization algorithm that searches for the optimal solution by simulating the social behavior of flocks of birds or schools of fish. The algorithm steps include: (1) Randomly generating a set of initial leaf curvatures as the particle swarm. (2) Evaluating the fitness (objective function value) of each particle. (3) Updating the velocity and position of each particle, considering the historical best position and the global best position of the particle. Repeat steps (2)-(3) until the maximum number of iterations is reached or the convergence condition is met.

[0123] When solving the optimization model, the airfoil controller queries the relevant aerodynamic data from the blade aerodynamic performance database based on the current external environment and blade condition, and substitutes this data into the optimization model for calculation. Through continuous iteration and searching, the optimal blade curvature adjustment scheme is finally obtained.

[0124] Example 2

[0125] like Figures 6 to 7 As shown, this embodiment provides an eddy current control system for an active control system of a wind turbine blade for wind power generation, including an eddy current generator 210 and an eddy current controller 220. The eddy current generator 210 is located near the blade tip and mainly includes the following components: an annular cavity 211, a radial pipe 215 of the annular cavity 211, an air hole 212, a solenoid valve 213, and a pressure sensor 214.

[0126] The main body of the vortex generator 210 is an annular cavity 211, which is mounted on the airfoil surface (external) of the wind turbine blade, near the blade tip. The design of the annular cavity 211 allows it to surround a portion of the blade, forming a ring-shaped structure around the blade tip. As the main structure of the vortex generator 210, the cavity provides space for fixing and protecting the internal ducts and vents 212, and serves as an airflow distribution center, ensuring that airflow can be evenly discharged or drawn in through the vents 212.

[0127] The annular cavity 211 contains multiple radially arranged channels that radiate outward from the center of the annular cavity 211. This radial arrangement helps to evenly distribute the vents 212, so as to more effectively control the airflow near the blade tip.

[0128] Numerous tiny air holes 212, approximately 2-3 mm in diameter, are symmetrically distributed at both ends or on both sides of the radial duct 215. The position and size of the air holes 212 are carefully designed to effectively alter the airflow pattern without affecting blade performance.

[0129] Each vent 212 can be independently controlled to open and close via a solenoid valve 213. The solenoid valve 213 is installed near the cavity or pipe and directly controls the state of one or more vents 212. The solenoid valve 213 is located near the vent 212 and connected to the pipe to control the ventilation state of the vent 212. When the eddy current controller 220 issues a command, the solenoid valve 213 opens or closes according to the command. If the valve is open, the vent 212 is ventilated, allowing airflow; if the valve is closed, the vent 212 is blocked, preventing airflow. In this way, the solenoid valve 213 can precisely control the ventilation state of each vent 212, thereby controlling the airflow rate discharged or drawn in from near the blade tip.

[0130] Solenoid valve 213 is fixed to the pipeline to ensure that gas can flow from the pipeline to solenoid valve 213, and then the flow to orifice 212 is controlled by solenoid valve 213. This fixing can be permanent or movable, depending on the requirements of the system design. If solenoid valve 213 is movably fixed to the pipeline, solenoid valve 213 can be removed from the pipeline or repositioned during maintenance or adjustment. This design allows maintenance personnel to easily replace, repair, or adjust solenoid valve 213 without replacing the entire piping system. Movable fixing is achieved using mechanical interfaces such as clamps, snap rings, bolts, or quick connectors, which can securely fix solenoid valve 213 to the pipeline while also allowing it to be removed when needed.

[0131] Pressure sensor 214 is connected to radial pipe 215 and is used to detect the dynamic pressure of the airflow flowing through orifice 212. Installed inside radial pipe 215, pressure sensor 214 can directly detect the dynamic pressure of the airflow on both sides of orifice 212, helping to obtain accurate pressure data. The pressure signal is fed back to vortex controller 220 at the blade root. Based on the pressure distribution, vortex controller 220 precisely controls the opening area of ​​each orifice 212 to change the velocity distribution and boundary layer structure near the blade tip, effectively suppressing vortex generation. This layout helps to obtain accurate pressure data because the sensor is directly exposed to the airflow without interference from other structures. By detecting the dynamic pressure of the airflow, vortex controller 220 can adjust the state of solenoid valve 213 according to the pressure signal, thereby precisely controlling the opening area of ​​orifice 212 and achieving active control of the airflow state near the blade tip.

[0132] The working principle of the eddy current generator 210 includes: by detecting the dynamic pressure of the airflow, the control system can adjust the state of the solenoid valve 213 according to the pressure signal, precisely control the opening area of ​​the air orifice 212, and achieve active control of the airflow state near the blade tip. The solenoid valve 213 is a valve controlled by an electromagnet. When the electromagnet is energized, it generates a magnetic field, attracting the ferromagnetic material inside the valve, causing it to move and changing the opening and closing state of the valve; when the electromagnet is de-energized, the valve returns to its original state by spring force or gravity.

[0133] The eddy current control system functions by having the porous eddy current generator 210, through radially arranged pipes and vents 212 within its annular cavity 211, and through precise control of the solenoid valve 213 and pressure sensor 214, work together to regulate the airflow near the blade tip, thereby controlling the eddy currents. This helps reduce noise, reduce blade tip losses, and improve the overall wind power generation efficiency of the wind turbine.

[0134] In some designs, the airflow through the vent 212 may originate from the pressure differential generated as the wind turbine blades rotate. In other cases, an external air source may be required, such as a compressed air system within the wind turbine tower, or a small compressor or gas storage device inside the blade. The duct serves only as a transport channel, conveying gas from the air source to the porous vortex generator 210 on the blade.

[0135] In one embodiment, the gas in the porous vortex generator 210 system is generated from an internal gas source within the wind turbine, transported through pipes, and discharged from vents 212 on the blade surface under the control of a solenoid valve 213, thereby regulating the airflow near the blade tip. In some designs, the airflow in the vents 212 may be driven by the air pressure difference generated by the rotation of the wind turbine blades themselves. In this case, the vents 212 may open or close naturally under specific pressure conditions, or the solenoid valve 213 may be used to control the airflow under these conditions. If a gas supply is required to regulate the airflow in the vents 212, this gas source can be external, such as a compressed air system inside the wind turbine tower, or a small compressor or other gas storage device inside the blade. In short, whether a gas source is needed depends on the specific design and operating principle of the porous vortex generator 210. If the vents 212 require an additional gas supply to function, then a gas source may be necessary. If the vents 212 can utilize existing airflow conditions or other mechanisms to regulate the airflow, then a gas source may not be required.

[0136] In summary, the eddy current control system provided in this embodiment effectively suppresses eddy current generation, improves wind turbine efficiency, and reduces noise by precisely controlling the airflow state near the blade tip. This design is compact, lightweight, and can be customized to meet specific needs.

[0137] Example 3

[0138] like Figure 8 and Figure 9 As shown, an active control system for wind turbine blades used in wind power generation also includes an eddy current control system, which includes an eddy current generator and an eddy current controller.

[0139] The eddy current generator, located near the blade tip, specifically includes:

[0140] An annular cavity has a first end face and a second end face. Between the first end face and the second end face, there are multiple axial channels extending along the blade length direction and distributed on the pressure surface and suction surface of the blade. Multiple air holes are respectively provided on the first end face and the second end face. Each axial channel is connected to a set of air holes provided on the first end face and the second end face.

[0141] The central manifold is located in the middle of the interior of the annular cavity and is connected to multiple axial pipes. The central manifold is also connected to the internal space of the blade. It is used to collect external airflow from multiple axial pipes and introduce it into the interior of the blade, or to distribute airflow generated from the air source inside the blade to multiple axial pipes for output to the outside of the blade.

[0142] Multiple solenoid valves, each of which is disposed near one or more air holes, are used to open or close one or more nearby air holes or adjust the opening area of ​​one or more nearby air holes according to the control command of the eddy current controller.

[0143] Multiple pressure sensors are respectively installed in multiple axial pipes to detect the pressure of the airflow and feed the pressure signal back to the eddy current controller;

[0144] The eddy current controller is used to control the working state of one or more corresponding solenoid valves, or to control the working state of the air source inside the blade, based on the pressure signal in the first set of axial pipes located on the pressure surface of the blade and the pressure signal in the second set of axial pipes located on the suction surface of the blade.

[0145] In this embodiment, the eddy current controller's main function is to adjust the airflow distribution on the blades in real time to adapt to different wind and operating conditions, optimize blade performance, reduce bending and vibration, and improve overall efficiency and stability. Here are a few specific examples to illustrate how the eddy current controller functions under different circumstances:

[0146] 1. High wind speed conditions

[0147] At high wind speeds, the forces acting on wind turbine blades increase significantly, potentially leading to excessive bending or even damage. In such cases, eddy current controllers can reduce the forward curvature of the blades by decreasing the opening area of ​​the vents on the pressure side and increasing the opening area of ​​the vents on the suction side. By adjusting the airflow on the pressure and suction sides of the blades, the degree of blade curvature can be effectively controlled, preventing structural damage caused by excessive wind speeds.

[0148] 2. Low wind speed conditions

[0149] At low wind speeds, wind turbines are typically less efficient. To improve energy capture efficiency at low wind speeds, eddy current controllers can increase the orifice opening area on the pressure surface, thereby increasing airflow over the blade's pressure surface and enhancing lift. This adjustment helps maintain blade stability and high efficiency at low wind speeds.

[0150] 3. Sudden wind conditions

[0151] When wind direction or speed changes abruptly, blades may be subjected to uneven airflow impacts, leading to vibration or other dynamic response problems. The eddy current controller can monitor pressure signals within the ducts along each axis in real time and quickly adjust solenoid valves to alter the airflow distribution on the pressure and suction surfaces of the blades. This rapid response can mitigate the bending and vibration of the blades caused by sudden wind changes, ensuring smooth turbine operation.

[0152] 4. Conditions for ice accumulation on the blade surface

[0153] Under freezing conditions, ice can accumulate on the blade surface, affecting its aerodynamic performance. Vortex controllers, by adjusting the opening area and distribution pattern of the orifices, can help change the temperature of the blade surface or physically disturb the ice, facilitating its shedding. Furthermore, appropriate airflow adjustments can prevent the formation of new ice.

[0154] 5. Multiple wind directions

[0155] Under changing wind conditions, blades need to adapt to airflow from different directions. The eddy current controller can detect changes in wind pressure from different directions and adjust the vents on the pressure and suction sides accordingly to maintain optimal blade attitude and efficiency.

[0156] Therefore, eddy current controllers can not only optimize the aerodynamic performance of blades, but also enhance the structural safety and adaptability of blades, reduce maintenance costs, and extend the service life of wind turbines.

[0157] This embodiment improves the aerodynamic efficiency of the blades by dynamically adjusting the airflow on the blades, thereby increasing the overall efficiency of wind power generation. This embodiment can precisely control the airflow near the blade tip and also reduce noise generated during wind turbine operation. By optimizing the pressure distribution on the blade surface, this embodiment can reduce blade fatigue caused by uneven airflow and extend the blade's service life.

[0158] Example 4

[0159] like Figure 6 As shown, in some embodiments, the active control system of the wind turbine blade further includes a load control system, which includes: strain gauges and accelerometers, installed at key locations on the blade surface and inside, for real-time monitoring of the blade's bending and vibration data; a load controller, for calculating the real-time load on each part of the blade based on the bending and vibration data fed back by the strain gauges and accelerometers; a blade bending and blade-induced vibration suppression module, for controlling the extension and retraction of the drive end of the drive device based on the detection information from the strain gauges and accelerometers, changing the curvature of the pressure and suction surfaces of the blade to suppress blade bending and blade-induced vibration; and an overload warning module, for optimizing the blade's airfoil control parameters and / or eddy current control parameters, or sending a shutdown signal, when the real-time load on the blade is detected to be greater than a preset load threshold; optimizing the blade's airfoil control parameters specifically includes: changing the blade's angle of attack or adjusting the airfoil curvature to reduce lift; and eddy current control parameters specifically include: the opening degree of the solenoid valve.

[0160] In some embodiments, strain gauges and accelerometers are arranged at the root, middle and tip of the blade to comprehensively monitor the bending and vibration of the blade in all directions.

[0161] The blade bending and blade-induced vibration suppression module is used to control the extension and retraction of the drive end of the drive device based on the detection information of the strain gauge and accelerometer, thereby changing the curvature of the pressure surface and suction surface of the blade to suppress blade bending and blade-induced vibration.

[0162] The overload warning module is specifically used to assess in real time whether the load on the blade exceeds the design threshold based on the real-time load provided by the load controller. Once an overload is detected, the blade airfoil control parameters are automatically adjusted. If the load is still too high after adjustment, the overload warning module will trigger an emergency shutdown procedure to stop the wind turbine from operating.

[0163] The blades are also equipped with sensors such as strain gauges and accelerometers, which can monitor the bending and vibration of the blades in real time. These feedback signals are also input to the microcontroller, which adjusts the blade state according to the blade load to avoid overload.

[0164] The working principle of the blade load control system is as follows:

[0165] Fiber optic strain gauges and accelerometers are installed at key locations on the blade surface and inside to monitor the blade's bending deformation and vibration acceleration in real time. These sensors are connected to a microcontroller at the blade root via signal lines, transmitting strain and acceleration data to the microcontroller at high frequency. The microcontroller has a built-in finite element model of the blade structure and can calculate the real-time stress and load on various parts of the blade based on sensor feedback.

[0166] When excessive blade load is detected, the microcontroller first optimizes the blade's airfoil and vortex control parameters to reduce aerodynamic load. If the load remains excessive after adjustment, indicating excessive wind force, the controller sends a shutdown signal to the wind turbine control system to prevent blade damage through emergency shutdown. After the overload condition is resolved, the microcontroller restarts the wind turbine according to the normal procedure. The entire process has a response time of less than 0.5 seconds, effectively preventing blade overload damage. Simultaneously, the data collected by the sensors is stored for blade structural health monitoring and fault prediction.

[0167] This active structural health monitoring system can protect the blades throughout the entire lifecycle of a wind turbine.

[0168] This embodiment provides an active or passive control system for wind turbine blades and a method for reducing wind load. Through innovative variable geometry blades and tip eddy current control technology, it effectively solves the problems in the prior art, significantly reduces the impact of wind load on the blades, extends the service life of the blades, improves the operational stability and power generation efficiency of wind turbines, reduces maintenance and operating costs, and improves the performance and economic benefits of wind turbines.

[0169] This invention employs a variable curvature blade system, improving the blade's adaptability to wind conditions and enhancing the wind turbine's operating efficiency. This invention also introduces a tip eddy current controller, effectively reducing eddy current losses at the blade tip and minimizing blade bending and vibration. Furthermore, this invention monitors and dynamically adjusts the blade's operating status in real time, improving the control system's response speed and accuracy.

[0170] Example 5

[0171] like Figure 10 As shown, this embodiment provides a method for an active control system of wind turbine blades for wind power generation. Based on the above-mentioned active control system for wind turbine blades, the method includes the following steps:

[0172] S1: Real-time monitoring of wind speed and direction via wind speed and direction sensors, and sending the monitoring results to the airfoil controller;

[0173] S2: The airfoil controller receives the monitoring results of wind speed and direction from the wind speed and direction sensors, and controls the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades based on the monitoring results.

[0174] In some embodiments, the method further includes the following steps:

[0175] S3: The airflow state near the blade tip is adjusted by a vortex generator located near the blade tip. The vortex generator includes multiple air holes and electromagnetic valves for independently controlling the opening and closing of the air holes.

[0176] S4: The dynamic pressure of the local airflow is detected by pressure sensors installed in the pipes on both sides of the air hole, and the pressure signal is fed back to the eddy current controller, which controls the working status of multiple solenoid valves.

[0177] In some embodiments, the method further includes the following steps:

[0178] S5: Real-time monitoring of blade bending and vibration data using strain gauges and accelerometers installed at key locations on the blade surface and inside;

[0179] S6: The load controller calculates the real-time load on each part of the blade based on the blade bending and vibration data fed back by the strain gauges and accelerometers.

[0180] S7: When the overload warning module detects that the real-time load on the blade is greater than the preset load threshold, it optimizes the airfoil control parameters and / or eddy current control parameters of the blade, or sends a shutdown signal when necessary; wherein, optimizing the airfoil control parameters of the blade includes changing the blade angle of attack or adjusting the airfoil curvature to reduce lift; the eddy current control parameters include the opening degree of the solenoid valve.

[0181] In some embodiments, in step S7, the overload warning module is specifically used to evaluate in real time whether the load borne by the blade exceeds the design threshold based on the real-time load data provided by the load controller; once an overload is detected, the parameters of the blade airfoil control system are automatically adjusted; if the load is still too high after adjustment, the overload warning module will trigger an emergency shutdown procedure to stop the wind turbine from operating.

[0182] In some embodiments, when the blade load is detected to be greater than a preset load threshold, the aerodynamic load is first reduced by optimizing the blade airfoil and vortex control parameters. If the load is still greater than the preset load threshold after adjustment, a shutdown control signal is sent to the main control system of the wind turbine to avoid blade overload damage through emergency shutdown.

[0183] Strain gauges are used to monitor blade bending based on the relationship between strain and stress. Accelerometers are used to monitor blade vibration characteristics, such as frequency and amplitude. The actual load on the blade is calculated using the collected data. A safe load threshold is determined based on the blade design and material properties. The real-time calculated load is compared with the preset threshold. If the load exceeds the threshold, an attempt is made to reduce the aerodynamic load by adjusting the blade airfoil and vortex control parameters. This involves changing the blade's angle of attack, pitch, or other aerodynamic characteristics, specifically by controlling the variable curvature blade system and the vortex controller. After adjustment, the load is reassessed to see if it still exceeds the threshold. If the load still exceeds the threshold after adjustment, a shutdown control signal is sent to the wind turbine's main control system. An emergency shutdown procedure is executed to quickly reduce the blade load and prevent damage. The wind turbine initiates an emergency braking procedure to rapidly reduce its rotational speed.

[0184] This invention employs a variable curvature blade system, improving the blade's adaptability to wind conditions and enhancing the wind turbine's operating efficiency. This invention also introduces a tip eddy current controller, effectively reducing eddy current losses at the blade tip and minimizing blade bending and vibration. Furthermore, this invention monitors and dynamically adjusts the blade's operating status in real time, improving the control system's response speed and accuracy.

[0185] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An active control system for wind turbine blades used in wind power generation, characterized in that, The active control system includes an airfoil control system, which includes: A wind turbine blade includes: a first group of movable blade segments and a second group of movable blade segments; the first group of movable blade segments is located on the pressure surface of the blade, and its movable blade segments are connected sequentially by hinges; the second group of movable blade segments is located on the suction surface of the blade, and its movable blade segments are connected sequentially by hinges; one end of the first group of movable blade segments and the second group of movable blade segments are respectively connected to the trailing edge of the blade to form a movable adjustment part of the trailing edge of the blade; the other end of the first group of movable blade segments is hinged to the upper main beam of the blade, and the other end of the second group of movable blade segments is hinged to the lower main beam of the blade; A blade airfoil adjustment mechanism is used to dynamically adjust the airfoil curvature of a wind turbine blade. The blade airfoil adjustment mechanism includes: a rigid connector connected to the web and trailing edge of the blade; and a drive device fixed to the rigid connector. The drive device is telescopically connected to a first set of movable blade segments and / or a second set of movable blade segments, and is used to independently or collaboratively extend, move, or rotate the movable blade segments. Wind speed and direction sensors are used to monitor wind speed and direction in real time and send the monitoring results to the airfoil controller; An airfoil controller, located at the blade root, is used to receive the monitoring results of wind speed and wind direction from the wind speed and wind direction sensors, and to control the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades according to the monitoring results. It also includes an eddy current control system, which comprises an eddy current generator and an eddy current controller; The eddy current generator, located near the blade tip, specifically includes: Multiple air holes are set on the annular cavity at positions corresponding to the pressure and suction surfaces of the blade, used to adjust the airflow state near the blade tip; Solenoid valves are used to independently control the opening and closing of air vents; A pressure sensor, installed inside a radial pipe, is used to detect the dynamic pressure of the airflow and feed the pressure signal back to the eddy current controller. An annular cavity has multiple radial channels radially opened inside the annular cavity. The pressure sensor is fixedly connected inside the radial channels. Multiple air holes are opened inside the annular cavity at the outer end or on both sides of the radial channels. The active control system further includes a load control system, which includes: Strain gauges and accelerometers are installed at key locations on the blade surface and inside to monitor the blade's bending and vibration data in real time. A load controller is used to calculate the real-time load on each part of the blade based on the bending and vibration data of the blade fed back by the strain gauges and accelerometers. The overload warning module is used to optimize the airfoil control parameters and / or eddy current control parameters of the blade or send a shutdown signal when the real-time load on the blade is detected to be greater than the preset load threshold. Specifically, the optimized blade airfoil control parameters include: changing the blade angle of attack or adjusting the airfoil curvature to reduce lift; the vortex control parameters specifically include: the opening degree of the solenoid valve.

2. The active control system for wind turbine blades for wind power generation according to claim 1, characterized in that, The drive device is specifically used for: independently controlling the extension, movement, or rotation of each group of movable blade segments under the control of the airfoil controller; and coordinating the adjustment of the position and / or angle of multiple movable blade segments; the drive device includes a hydraulic servo drive device, which changes the curvature of the blade pressure surface or suction surface by means of the extension and retraction of the drive end.

3. The active control system for wind turbine blades for wind power generation according to claim 1, characterized in that, The airfoil controller is used to receive external environmental status information and blade status information, calculate the optimal blade curvature adjustment scheme under the condition of limited segmentation of the blade pressure surface and suction surface, and control the drive device to make corresponding adjustments according to the optimal blade curvature adjustment scheme. The external environment status information includes the wind speed and wind direction at the wind turbine's altitude; the blade status information includes: feathering state, standby state, or operating state, with the operating state specifically referring to the current blade angle of attack.

4. The active control system for wind turbine blades for wind power generation according to claim 1, characterized in that, The strain gauges and accelerometers are arranged at the root, middle and tip of the blade to comprehensively monitor the bending and vibration of the blade in all directions. The blade bending and blade-induced vibration suppression module is used to control the extension and retraction of the drive end of the drive device based on the detection information of the strain gauge and accelerometer, thereby changing the curvature of the pressure surface and suction surface of the blade to suppress blade bending and blade-induced vibration. The overload warning module is specifically used to evaluate in real time whether the load on the blade exceeds the design threshold based on the real-time load provided by the load controller; once an overload is detected, the blade airfoil control parameters are automatically adjusted. If the load remains too high after adjustment, the overload warning module will trigger an emergency shutdown procedure to stop the wind turbine from operating.

5. An active control method for wind turbine blades used in wind power generation, characterized in that, The method is based on the active control system for wind turbine blades used in wind power generation according to any one of claims 1-4, and the method includes the following steps: S1: Real-time monitoring of wind speed and direction via wind speed and direction sensors, and sending the monitoring results to the airfoil controller; S2: The airfoil controller receives the monitoring results of wind speed and wind direction from the wind speed and wind direction sensors, and controls the airfoil adjustment mechanism to adjust the airfoil curvature of the wind turbine blades according to the monitoring results.

6. The active control method for wind turbine blades for wind power generation according to claim 5, characterized in that, The method also Includes the following steps: S3: Adjust the airflow state near the blade tip by setting a vortex generator near the blade tip. The vortex generator includes multiple air holes and electromagnetic valves for independently controlling the opening and closing of the air holes. S4: The dynamic pressure of the local airflow is detected by pressure sensors installed in the pipes on both sides of the air hole, and the pressure signal is fed back to the eddy current controller, which controls the working state of the multiple solenoid valves.

7. The active control method for wind turbine blades for wind power generation according to claim 5, characterized in that, The method further includes the following steps: S5: Real-time monitoring of blade bending and vibration data using strain gauges and accelerometers installed at key locations on the blade surface and inside; S6: The load controller calculates the real-time load on each part of the blade based on the blade bending and vibration data fed back by the strain gauges and accelerometers; S7: When the overload warning module detects that the real-time load on the blade is greater than the preset load threshold, it optimizes the airfoil control parameters and / or eddy current control parameters of the blade, or sends a shutdown signal; among them, optimizing the airfoil control parameters of the blade includes changing the blade angle of attack or adjusting the airfoil curvature to reduce lift; the eddy current control parameters include the opening degree of the solenoid valve.

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