Wind turbine blade, wind turbine blade production method, wind turbine, and damper system

Abstract

A wind turbine blade, a wind turbine blade production method, a wind turbine, and a damper system. The damper system (22) is provided on the wind turbine blade, and the damper system (22) comprises a damper unit (11) arranged in the spanwise direction of the wind turbine blade or a plurality of damper units (11) arranged in parallel and spaced apart from each other. The damper unit (11) comprises an energy consumption circuit, a magnetic device (3) and an elastic element (5). The energy consumption circuit is a loop comprising an energy consumption device (2) and an inductive device (6) which are connected to each other. A target element is the inductive device (6) or the magnetic device (3), and a target system comprises the elastic element (5) and the target element. When the vibration direction of the target element and the edgewise direction of a blade meet a preset angle range, and when the difference between the inherent frequency of the target system and the blade vibration frequency of a wind turbine blade meets a preset range, the target system resonates with the wind turbine blade, such that relative motion occurs between the inductive device (6) and the magnetic device (3), an induced current is generated in the energy consumption circuit, and the induced current consumes energy by means of the energy consumption device and the inductive device, so as to increase the damping of the blade.

Description

Wind turbine blade, wind turbine blade production method, wind turbine generator and damper system

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 31, 2023, with application number 202311122642.4, and invention name “Wind blade, wind blade production method, wind turbine and damper system”, and this application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 22, 2024, with application number 202411164197.2, and invention name “Wind blade, wind blade production method, wind turbine and damper system”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of wind power technology, and in particular to a wind turbine blade, a method for producing a wind turbine blade, a wind turbine generator, and a damper system. Background Art

[0003] Under certain operating conditions, wind turbine blades can experience negative damping, generating self-excited vibrations. This vibration can damage the blades and affect the safe operation of the wind turbine. Negative damping typically occurs during the oscillation of wind turbine blades due to the high aerodynamic damping experienced by the blades in the flapping direction.

[0004] At present, there is an urgent need to solve the negative damping problem of wind turbine blades in the swing direction.

[0005] Summary of the Invention

[0006] In order to solve the above technical problems, the present application provides a wind turbine blade, a wind turbine blade production method, a wind turbine generator and a damper system, which can effectively solve the negative damping problem of the blade in the swing direction, ensure the normal operation of the blade, and improve the operation safety of the wind turbine equipment.

[0007] In order to achieve the above objectives, the technical solutions provided by this application are as follows:

[0008] In a first aspect, the present application provides a fan blade, wherein a damper system is provided on the fan blade; the damper system includes a damper unit arranged in a span direction of the fan blade or a plurality of damper units arranged in parallel and spaced apart;

[0009] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0010] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0011] The movable direction of the target element vibration in the damper unit and the blade swing direction of the fan blade meet a preset angle range; wherein the target element is the inductive device or the magnetic device;

[0012] The elastic element and the target element are elements in a target system, and the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade satisfies a preset range that enables the target system and the fan blade to resonate, so that the target system and the fan blade resonate, causing relative movement between the magnetic device and the inductive device.

[0013] In a second aspect, the present application provides a method for producing a wind turbine blade, the method comprising:

[0014] Obtain the blade vibration frequency of the fan blade;

[0015] Determining the natural frequency of a target system based on the blade vibration frequency and frequency deviation range of the fan blade, and selecting an elastic element based on the natural frequency of the target system; the target system includes the elastic element and a target element; the target element is an inductive device or a magnetic device;

[0016] Setting the movable direction of the target element in the damper unit and the blade swing direction of the fan blade to meet a preset angle range;

[0017] An energy consumption circuit is provided as a loop and includes an energy consumption device and the inductive device connected to each other, and a damper unit is provided including the energy consumption circuit, the magnetic device and the elastic element;

[0018] A damper system is arranged on the fan blade, and the damper system includes a damper unit arranged in the span direction of the fan blade or a plurality of damper units arranged in parallel and spaced apart, so that the target system in the damper unit resonates with the fan blade, so that relative movement occurs between the magnetic device and the inductive device in the damper unit.

[0019] In a third aspect, the present application provides a wind turbine, which includes the wind turbine blade provided in the first aspect of the present application.

[0020] In a fourth aspect, the present application provides a damper system, the damper system comprising a damper unit arranged in a target direction of a target object or a plurality of damper units arranged in parallel and spaced apart;

[0021] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0022] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0023] The movable direction of the target element in the damper unit and the vibration direction of the target object satisfy a preset angle range; wherein the target element is the inductive device or the magnetic device; the vibration direction and the target direction are perpendicular to each other;

[0024] The elastic element and the target element are elements in a target system; the difference between the natural frequency of the target system and the vibration frequency of the target object satisfies a preset range that enables the target system and the target object to resonate, so that the target system and the target object resonate, causing relative movement between the magnetic device and the inductive device.

[0025] Through the above technical solution, it can be seen that this application has the following beneficial effects:

[0026] The present application provides a wind turbine blade, a method for producing a wind turbine blade, a wind turbine generator, and a damper system. The damper system is provided on the wind turbine blade and includes a damper unit or multiple damper units spaced parallel to each other in the span direction of the wind turbine blade. The damper unit includes an energy dissipation circuit, a magnetic device, and an elastic element. The magnetic device is capable of generating a magnetic field. The energy dissipation circuit is a loop comprising a connected energy dissipation device and an inductive device. The damper unit includes a target element. Depending on the specific structural design of the damper unit, the target element can be an inductive device or a magnetic device. The target element's movable direction within the damper unit and the blade swing direction of the wind turbine blade fall within a preset angular range. The damper unit also includes a target system, which includes an elastic element and a target element. When the target element's movable direction within the damper unit and the blade swing direction of the wind turbine blade fall within a preset angular range, and the difference between the target system's natural frequency and the blade vibration frequency of the wind turbine blade falls within a preset range, the target system resonates with the wind turbine blade. During resonance, the elastic element and target element in the target system will move. Regardless of whether the target element is an inductive device or a magnetic device, relative motion will occur between the inductive device and the magnetic device. The inductive device cuts the magnetic flux lines in the magnetic field, causing the magnetic flux in the energy dissipation circuit to change. Because the energy dissipation circuit is a loop, this will further cause the inductive device to generate an induced electromotive force, which in turn generates an induced current in the energy dissipation circuit. The energy dissipation circuit includes energy dissipation devices and inductive devices. The induced current passing through the energy dissipation devices and the inductive devices consumes energy, which dissipates the vibration energy of the blade as a whole in the swing direction. This can increase blade damping, reducing the risk of damage to the blade due to vibration caused by negative damping, thereby improving the safety of blade operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0028] FIG1 is a schematic diagram of a magnet-coil system provided in an embodiment of the present application;

[0029] FIG2 is a schematic diagram of a fan blade provided in an embodiment of the present application;

[0030] FIG3 is a schematic diagram of a connection method of an inductive device, an energy consumption device, and a capacitive device provided in an embodiment of the present application;

[0031] 4a and 4b are schematic structural diagrams of a damper unit provided in an embodiment of the present application;

[0032] 5a and 5b are schematic diagrams of a three-dimensional structure of a damper unit provided in an embodiment of the present application;

[0033] 6a to 7b are schematic structural diagrams of a damper unit provided in an embodiment of the present application;

[0034] FIG8 is a flow chart of a method for producing a fan blade according to an embodiment of the present application;

[0035] FIG9 is a schematic diagram of a blade damping ratio provided in an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] In order to facilitate understanding and explanation of the technical solutions provided by the embodiments of the present application, the background technology involved in the embodiments of the present application is first introduced.

[0038] The blades of wind turbines (such as horizontal axis wind turbines) will produce flutter under certain operating conditions. Flutter is the self-excited vibration caused by the bending and torsional coupled deformation of the blades under the action of aerodynamic forces. In this state, the aerodynamic damping of the blades is negative, and the blade vibration diverges exponentially. Among them, aerodynamic damping refers to the obstruction caused by the fluid to the structure, which consumes energy and affects the vibration of the structure. Self-excited vibration refers to the vibration caused by the transformation of the fluid inside the mechanical system from non-vibration excitation to vibration excitation, which corresponds to negative damping in the vibration differential equation. In practical applications, the negative damping phenomenon caused by this flutter may cause damage to the blades and affect the safe operation of the wind turbine equipment.

[0039] During the operation of a wind turbine, the vibration forms of the wind turbine blades include swing and flapping. The direction of the wind turbine blades during swing is different from the direction of the wind turbine blades during flapping. Swing refers to the movement of the wind turbine blades in the chord length direction of the blades in the blade root coordinate system. The chord length direction is the direction extending from the blade root to the blade tip. The chord length direction is the swing direction. Flapping refers to the movement of the wind turbine blades in the flapping direction in the blade root coordinate system. The flapping direction is the direction of movement of the wind turbine blade pressure surface relative to the suction surface. In actual applications, the force area of ​​the blades in the flapping direction is large and the aerodynamic damping is large, while the force area of ​​the blades in the swing direction is small and the aerodynamic damping is small. This makes the negative damping phenomenon caused by flutter usually occur during the swing process of wind turbine blades.

[0040] At present, there is an urgent need to solve the negative damping problem of wind turbine blades in the swing direction.

[0041] Based on this, embodiments of the present application provide a wind turbine blade, a wind turbine generator, and a wind turbine blade production method, wherein a damper system is provided on the wind turbine blade. The damper system includes a damper unit or multiple damper units spaced parallel to each other in the span direction of the wind turbine blade. The damper unit includes an energy dissipation circuit, a magnetic device, and an elastic element. The magnetic device is capable of generating a magnetic field. The energy dissipation circuit is a loop comprising a connected energy dissipation device and an inductive device. The damper unit contains a target element. Depending on the specific structural design of the damper unit, the target element can be an inductive device or a magnetic device. The target element's movable direction within the damper unit and the blade swing direction of the wind turbine blade fall within a preset angular range. The damper unit also contains a target system, which includes an elastic element and a target element. When the target element's movable direction within the damper unit and the blade swing direction of the wind turbine blade fall within a preset angular range, and the difference between the target system's natural frequency and the blade vibration frequency of the wind turbine blade falls within a preset range, the target system resonates with the wind turbine blade. During resonance, the elastic element and target element in the target system will move. Regardless of whether the target element is an inductive or magnetic device, relative motion will occur between the inductive and magnetic devices. The inductive device cuts through the magnetic flux lines in the magnetic field, causing the magnetic flux in the energy dissipation circuit to change. Because the energy dissipation circuit is a loop, this further causes the inductive device to generate an induced electromotive force, which in turn generates an induced current in the energy dissipation circuit. The energy dissipation circuit includes energy dissipation devices and inductive devices. The induced current passing through the energy dissipation devices and inductive devices consumes energy, which dissipates the vibration energy of the blade as a whole in the swing direction. This increases blade damping, reducing the risk of damage to the blade due to vibration caused by negative damping, thereby improving blade operation safety.

[0042] It is understandable that the defects in the above solutions are the results obtained by the applicant after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed in the embodiments of the present application below should be the applicant's contribution to the embodiments of the present application during the application process.

[0043] In order to facilitate understanding of the fan blade provided with a damper system in the embodiment of the present application, the relevant principles of providing a damper system to increase the damping of the fan blade are first explained below.

[0044] Let me first explain some technical terms.

[0045] Magnetic flux: The product of magnetic induction intensity B and the area S of a plane (effective area s, that is, the area passing perpendicularly through the magnetic field lines) is called the magnetic flux passing through the plane.

[0046] Magnetic density: also known as magnetic induction intensity, represents the number of magnetic lines of force passing vertically through a unit area.

[0047] Remanent Flux Density: The magnetic flux density remaining in the core after the excitation magnetic field is removed from the saturation state.

[0048] Referring to FIG1 , FIG1 is a schematic diagram of a magnet-coil system provided in an embodiment of the present application. As shown in FIG1 , a reference coordinate system rx is provided, in which there are two directions, namely the r direction and the x direction, as shown in the figure. The x direction is exemplarily the vertical direction, and the r direction is exemplarily the horizontal direction. The magnet can move in the x direction, and there are magnetic fields and magnetic flux lines around the magnet. The coil can be an inductor coil in an RLC series circuit (see FIG3 (a)), and the RLC series circuit in which the coil is located is a loop. When the magnet moves in the x direction, the position of the coil is fixed, and the coil as a conductor will cut the magnetic flux lines around the magnet, perform cutting magnetic flux lines movement, and the magnetic flux in the coil changes. Since the circuit in which the coil is located is a loop, electromagnetic induction phenomenon, i.e., magnetoelectric phenomenon, will occur. The generation of the magnetoelectric phenomenon will cause an induced electromotive force to be generated in the RLC series circuit, and then generate an induced current in the coil.

[0049] As shown in Figure 1, the positions of the coil and magnet can be described in the reference coordinate system rx. Here, x1 and x2 are the coordinates of the upper and lower surfaces of the coil in the thickness direction (i.e., the x direction), x is any position in the vertical direction (i.e., the x direction), y is the current position of the magnet in the x direction, and r1 is the radius of the coil. From this, it can be seen that the magnetic density between the magnet and the coil can be expressed as:

[0050] Where B is the magnetic density at any position in the reference coordinate system rx, B ris the residual magnetic flux density. In the magnetic density formula, v is the volume of the magnet, and Represent the two unit vectors in the x and r directions of the magnet in Figure 1. The x in the formula is any position in the x direction in the coordinate system, and the r in the formula is any position in the r direction in the coordinate system. Due to the electromagnetic induction phenomenon, the induced electromotive force generated in the N-turn coil can be expressed as V n , whose value can be determined by the magnetic flux Φ n The rate of change is expressed as follows:

[0051] Among them, S n is the coil area, da is the effective area perpendicular to the coil, and the induced electromotive force can be further expressed as follows:

[0052] Where ξ is the filling factor, represents the speed of the magnet in the x direction, and ΔA is the area swept by the N turns of coil. The expression for the filling factor is:

[0053] Among them, A w is the coil swept area. Based on this, the induced current generated in the RLC series circuit satisfies the following formula:

[0054] Among them, U C is the voltage across the capacitor, L is the inductance, R is the resistance, and C is the capacitance. Based on this, the electromagnetic induction force Q mag It can be expressed as:

[0055] Q mag =∫ v I×Bdv

[0056] In Figure 1, the movement of the magnet in the x-direction can be understood as vibration.

[0057] Based on the above, we can see that if the coil is fixed in position and the magnet moves relative to the coil, while the coil is in a loop, electromagnetic induction will occur, generating an induced electromotive force and an induced current in the coil. At this point, if there is a resistor in the loop, the resistor acts as an energy-consuming element. Current flowing through the resistor consumes energy, and current passing through the inductor in the coil also dissipates energy. Increased energy consumption increases the damping of the loop. Correspondingly, if the magnet is fixed in position and the coil moves relative to the magnet, while remaining in the loop, the same effect will occur.

[0058] Based on the above, if this circuit is installed in a fan blade, the blade's vibration energy will be dissipated through the circuit, increasing the circuit's damping and, accordingly, increasing the blade's damping. The above outlines the principles for increasing fan blade damping. Based on this principle, the specific structure of the damper system installed on the fan blade can be designed as follows.

[0059] In the damper system, a magnet-spring system can be set up. When the magnet vibrates, the spring and the magnet move in the same direction. After the electromagnetic induction phenomenon occurs, the structural vibration differential equation of the magnet is:

[0060] Where m is the mass of the magnet, r s is the structural damping coefficient of the magnet-spring system, k is the spring stiffness or the stiffness coefficient of the spring's elastic element. If the fan blade's vibration distance is z, its vibration amplitude is Λ (the vibration amplitude can be understood as the maximum vibration distance), and the blade's vibration frequency is Ω, then z = Λcos(Ωt).

[0061] On the basis of the magnet-spring system, in order to enable relative movement between the coil and the magnet, the embodiment of the present application can be implemented in the following manner.

[0062] Specifically, the natural frequency of the magnet-spring system is determined. The natural frequency refers to the inherent vibration frequency of the elastic body or elastic system itself. The natural frequency of the magnet-spring system is ω s , its formula is expressed as:

[0063] If the blade vibration frequency is close to the natural frequency of the magnet-spring system, that is, Ω≈ω s , the magnet-spring system and the fan blade will resonate and make the magnet-spring system have a larger response amplitude, so that the magnet-spring system will move relative to the fixed coil, and the magnet will have a speed relative to the coil. It can be seen that a larger response amplitude can maximize the change in magnetic flux. At this time, the electromagnetic induction phenomenon will cause an induced electromotive force, which will generate an induced current in the coil. Among them, the natural frequency of the magnet-spring system can be adjusted by the stiffness coefficient of the spring's elastic element.

[0064] In order to make the induced current larger, further, when the coil loop also includes a capacitor, such as the RLC series circuit shown in Figure 3(a), the resonant frequency ω of the current in the coil of the RLC series circuit is I It can be expressed as:

[0065] When the blade vibration frequency, the natural frequency of the magnet-spring system and the resonant frequency of the current are close, that is, Ω≈ωs ≈ω I When the induction current in the coil increases, the energy consumption in the resistor and the inductance of the coil will further increase, which will further increase the damping in the blade. The resonant frequency of the current in the RLC series circuit can be adjusted by the capacitance and inductance values.

[0066] Based on the above, embodiments of the present application provide a fan blade having a damper system disposed therein. It should be understood that the various specific structures of the damper system in the embodiments of the present application are implemented using the above-described design principles and can be used to increase the damping of the fan blade, as described below.

[0067] See Figure 2, which is a schematic diagram of a wind turbine blade according to an embodiment of the present application. As shown in Figure 2, the blade root coordinate system is a YZ coordinate system, where the Y direction represents the blade swing direction, and the Z direction represents the blade span direction. The blade span direction and the blade swing direction are perpendicular to each other, i.e., the Y and Z directions are perpendicular to each other.

[0068] The following first introduces the installation position of the damper system in the fan blade.

[0069] As shown in FIG2 , for example, the damper system 22 includes a damper unit 11 or multiple damper units 11 arranged in parallel and spaced apart in the span direction (Z direction) of the wind turbine blade. “Parallel and spaced apart” means that the multiple damper units may not be in contact with each other, and the damper units are arranged in parallel and spaced apart from each other. The spacing is not limited here. The number of damper units can be expressed as N c , N c is a positive integer, that is, N c The damper system consists of N damper units, and N c The damper units are distributed along the span direction (Z direction) of the blade. It is understandable that each damper unit can increase the damping of the fan blade, and the number of damper units determines the magnitude of the increased damping of the fan blade. The more damper units there are, the greater the increased damping of the fan blade.

[0070] As an optional example, the damper system is mounted on one or more of an inner surface of the fan blade skin, an outer surface of the fan blade skin, and a main beam region of the fan blade.

[0071] Among them, the main beam refers to the main load-bearing structure in the blade, which is made of fiber and matrix infusion, and provides support for the cavity structure of the blade. The blade also includes a web, which refers to the structure in the blade that supports the upper and lower shells of the blade airfoil, and plays a role in shear resistance. It is divided into single web and double web structures, and is usually bonded to the main beam structure of the blade. The blade skin is used to support the geometric shape of the blade, and the blade skin plate shell can be composed of composite laminates. The blade skin includes the inner surface of the blade skin and the outer surface of the blade skin. The main beam area of ​​the wind turbine blade is the vicinity of the main beam of the wind turbine blade. This vicinity is not limited here and can be determined according to actual conditions.

[0072] Furthermore, the installation location of the damper system within the blade can be determined based on actual circumstances. This is not a limitation. It is sufficient to ensure that, when the damper system includes multiple damper units, the multiple damper units are positioned in the spanwise direction (Z direction) of the wind turbine blade. In practical applications, the damper system can be installed within the wind turbine blade by bolting or gluing.

[0073] As shown in FIG2 , the distance between the installation start end (the end away from the blade root) of the damper system 22 on the fan blade and the tip of the fan blade in the Z direction is represented by d1. The distance between the installation end end (the end close to the blade root) of the damper system 22 on the fan blade and the tip of the fan blade in the Z direction is represented by d2. The length of the blade is represented by L blade .

[0074] It can be seen that the vibration modes of the fan blades of a wind turbine (such as a horizontal axis wind turbine) when they swing are usually first-order swing vibration and second-order swing vibration. Among them, the vibration mode refers to the form of vibration of the system and is independent of the magnitude of the vibration displacement. During the swing of the fan blades, there will be vibration nodes on the fan blades. Vibration nodes, also called mechanical vibration vibration mode nodes, refer to the intersection nodes of the vibration mode and the original shape of the structure at a certain natural frequency. The swing amplitude at the vibration mode node is zero. First-order swing vibration refers to the swing vibration with zero vibration nodes, and second-order swing vibration refers to the swing vibration with one vibration node.

[0075] It can be understood that at the vibration mode node, the swing amplitude of the fan blade is 0, the fan blade does not vibrate, and the fan blade has no blade vibration frequency. Based on this, if the damper system is installed at the vibration mode node of the fan blade, the damper system installed on the fan blade has no excitation source to resonate with the fan blade, and the fan blade and the target system in the damper system (the target system is a partial component of the damper system, see below) will not resonate, and the damper system cannot increase the damping of the fan blade. Based on this, as an optional example, the damper system is installed at a non-vibration mode node of the fan blade. A non-vibration mode node is a position in the fan blade that is not a vibration node.

[0076] The distance from the damper system to the blade tip is determined based on the blade's swing mode, assuming the damper system is installed at a non-modal node on the fan blade. This distance is the distance from the damper system's installation point to the blade tip, or d1.

[0077] Specifically, when the blade shimmy vibration mode is a first-order shimmy vibration, the distance from the damper system to the tip of the fan blade is a first distance value; when the blade shimmy vibration mode is a second-order shimmy vibration, the distance from the damper system to the tip of the fan blade is a second distance value. The first distance value is smaller than the second distance value.

[0078] It should be understood that the embodiments of the present application do not limit the specific values ​​of the first and second distance values, and they can be determined based on actual conditions. For example, when the vibration mode is first-order shimmy, the first distance value is 1 / 3 of the fan blade; when the vibration mode is second-order shimmy, the second distance value is 1 / 2 of the fan blade. The setting result of "the first distance value for first-order shimmy is less than the second distance value for second-order shimmy" can be determined based on actual testing. In actual conditions, when second-order shimmy occurs, in order to enhance the damping effect of the damper system on the fan blade, the second distance value is set to be greater than the first distance value.

[0079] As an optional example, based on the above determination of the distance from the damper system to the tip of the fan blade, d1 / L can also be satisfied at the same time blade ≥0.2, d2 / L blade ≥0.6. This range constraint is obtained through actual experiments and can enable the damper system at this installation position to better increase the damping effect for the fan blades.

[0080] It can be seen that the multiple damper units in the damper system are arranged in the span direction of the fan blade, and the installation position of the damper system on the fan blade can be determined according to d1 and d2. On this basis, it is also necessary to ensure that the vibration reduction direction (or vibration direction, movement direction) of the target system (see below) in the damper system and the blade swing direction meet the preset angle range, which is a condition for achieving resonance between the target system and the fan blade in the damper system. Among them, the preset angle range is a range greater than or equal to 0 degrees and less than or equal to the target angle. In practice, the preset angle range is a smaller angle range greater than or equal to 0 degrees, that is, the target angle is close to or equal to 0. The embodiment of the present application does not limit the specific preset angle range. When the target angle is 0 degrees, the vibration direction of the target system is the blade swing direction, that is, the Y direction. At this time, if the target system in the damper system resonates with the fan blade, the amplitude of the resonance is large.

[0081] The internal structure of the damper unit in the damper system will be introduced in detail below.

[0082] As an optional example, the damper unit 11 includes an energy consumption circuit, a magnetic device and an elastic element.

[0083] The energy dissipation circuit is a loop comprising connected energy dissipation devices and inductive devices. For example, the loop can be a closed loop. The damper unit contains a target element and a target system. The target system includes an elastic element and a target element. Depending on the installation position of the various structures in the damper unit, the target element can be an inductive device or a magnetic device. The vibration direction of the target element and the blade swing direction of the fan blades must fall within a preset angular range, and the difference between the natural frequency of the target system and the blade vibration frequency of the fan blades must fall within a preset range that allows the target system and the fan blades to resonate.

[0084] Magnetic devices, also known as magnetic materials, primarily refer to materials composed of transition elements such as iron, cobalt, nickel, and their alloys that can directly or indirectly generate magnetism. Magnetic materials can generate magnetic fields. For example, elastic elements are springs or other components with elastic stiffness coefficients, though the type of spring is not limited. For example, energy dissipation devices can be resistors or other energy-dissipating devices. For example, inductive devices can be conductive metal materials such as coils, copper tubes, aluminum tubes, and iron tubes.

[0085] In practical applications, the resistor device is an adjustable resistor device, and the resistance value of the adjustable resistor device is adjustable. By adjusting the resistance value of the resistor device, the current in the energy consumption circuit can be changed. Since the energy dissipated in the energy consumption circuit = I 2 R, then the change in current can change the energy consumption of the energy-consuming device, thereby changing the blade damping of the wind turbine blade. For example, the inductive device, capacitive device (see below for details), elastic element, etc. in the embodiments of the present application can also adopt inductive devices with adjustable inductance values, capacitive devices with adjustable capacitance values, elastic elements with adjustable elastic element stiffness coefficients, etc., to facilitate the adjustment of parameters such as inductance values, capacitance values, and elastic element stiffness coefficients.

[0086] It can be seen that when the resistor is a non-adjustable resistor, it is possible to directly select a resistor with an appropriate resistance value to meet the energy consumption requirement. Similarly, it is also possible to directly select an inductive device with an appropriate inductance value, a capacitive device with an appropriate capacitance value (see below for details), or an elastic element with an appropriate elastic element stiffness.

[0087] The damper unit may include one or more magnetic components, and one or more inductive components. When the damper unit includes multiple magnetic components, the multiple magnetic components may be arranged in parallel. When the damper unit includes multiple inductive components, the multiple inductive components may also be arranged in parallel.

[0088] The central axis positions of the inductive device and the magnetic device are the same or close to each other, so that when the inductive device and the magnetic device move relative to each other, the inductive device cuts the magnetic flux of the magnetic device, the magnetic flux passing through the inductive device changes, and electromagnetic induction occurs. Here, "close" means that there is a distance difference or angle difference between the central axis of the inductive device and the central axis of the magnetic device. The distance difference or angle difference between the central axis of the inductive device and the central axis of the magnetic device can be determined according to actual conditions and is not limited here. It is only necessary that when the two move relative to each other, they can cut the magnetic flux to generate an induced current. For example, when the inductive device is a coil and the magnetic device is a magnet, the central axis directions of the coil and the magnetic device are both in the x direction as shown in Figure 1, and the central axes coincide.

[0089] In practical applications, the inductive device can move relative to the magnetic device, meaning it is the inductive device that moves / vibrates; or the magnetic device can move relative to the inductive device, meaning it is the magnetic device that moves / vibrates. Therefore, if the target element is the structure in the damper system that resonates with the wind blade together with the elastic element, then the target element can be either an inductive or magnetic device. The target element is a component in the target system, which also includes the elastic element. When the target element vibrates, the elastic element in the target system also vibrates in the same direction. This can be understood as the target element vibrating in the same direction as the elastic element, i.e., the direction of the target system's vibration. This can also be understood as the target system being the structure in the damper system that resonates with the wind blade.

[0090] The natural frequency of the target system is set so that the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meets a preset range, which is another condition for achieving resonance between the target system in the damper unit and the fan blade. Among them, the preset range is a range greater than or equal to 0 degrees and less than or equal to the target value, which is a smaller angle range greater than or equal to 0, that is, the target value is close to or equal to 0. The embodiment of the present application does not limit the specific preset range. When the target value is 0, if the target system in the damper system resonates with the fan blade, the resonance effect (which can be reflected in a larger resonance amplitude) is better.

[0091] As an alternative example, the natural frequency of the target system The natural frequency of the target system can be changed by adjusting the elastic element stiffness coefficient k of the elastic element, so that the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade satisfies a preset range that enables the target system and the fan blade to resonate. "Adjustment" can be understood as directly adjusting the elastic element stiffness coefficient of the elastic element when the elastic element is an elastic element with an adjustable elastic element stiffness coefficient; "adjustment" can also be understood as adjusting the elastic element in the damper system when the elastic element is an elastic element with an unadjustable elastic element stiffness coefficient, that is, directly selecting an elastic element whose elastic element stiffness coefficient enables the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade to satisfy a preset range that enables the target system and the fan blade to resonate.

[0092] Then, when the movable direction of the target element in the damper unit (that is, the direction of the target element when vibrating in the damper unit) and the blade swing direction of the fan blade meet the preset angle range, further if the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meets the preset range (it can be considered that Ω≈ω s ), indicating that the conditions for resonance between the target system and the wind turbine blade are met. At this point, the target system resonates with the wind turbine blade, resonating with the ground excitation, and exhibiting a large response amplitude / vibration amplitude. If the target element in the target system has a large response amplitude, then relative motion will occur between the inductive and magnetic components, regardless of whether the target element is an inductive device or a magnetic device. The inductive device cuts through the magnetic flux lines in the magnetic field, causing a change in the magnetic flux in the energy dissipation circuit. Since the energy dissipation circuit is a loop, this generates an induced electromotive force in the inductive device, which in turn generates an induced current in the energy dissipation circuit. The energy dissipation circuit contains both energy dissipating and inductive components, and the induced current dissipates energy through these components. In other words, the vibration energy of the wind turbine blade can be dissipated by the energy dissipating and inductive components in the damper unit, thereby increasing blade damping. In practical applications, experiments have shown that increasing the damping of the energy dissipation circuit in each damper unit installed in a wind turbine blade is equivalent to increasing the damping of the wind turbine blade. Furthermore, as the damping of the fan blade increases, the damping ratio also increases accordingly. Damping is the friction and other resistance that attenuates free vibration. The damping ratio is the ratio of the damping coefficient to the critical damping coefficient, expressing the normalized damping of the structure.

[0093] As an optional example, as mentioned above, when the vibration direction of the target element is the same as the blade swing direction (Y direction) of the wind turbine blade, the resonance amplitude of the target system is greater.

[0094] Based on the above, it can be seen that the installation of a damper system in wind turbine blades can effectively solve the problem of negative damping in the swing direction of wind turbine blades, improving the operational safety of wind turbine equipment. Furthermore, since the fatigue load of wind turbine blades is related to the amplitude of the alternating load, increasing the damping of wind turbine blades can also reduce the amplitude of the alternating load, thereby reducing the fatigue load of wind turbine blades and further improving the safety and reliability of the unit. Furthermore, reducing the fatigue load of wind turbine blades can also save materials that would otherwise be used to solve the problem of negative damping in the blades, reducing material costs and saving on blade design and manufacturing costs.

[0095] It is understood that the two conditions for resonance between the target system and the fan blades are that the vibration direction of the target element in the damper unit and the blade swing direction of the fan blades fall within a preset angular range, and that the difference between the natural frequency of the target system and the blade vibration frequency of the fan blades falls within a preset range. Therefore, it is sufficient that the vibration direction of the target element in each damper unit and the natural frequency of the target system both meet these two conditions, and there is no requirement that the vibration direction of the target element in each damper unit and the natural frequency of the target system be the same.

[0096] It's also understandable that, in practice, the natural frequency of an object is approximately several thousand hertz, while the vibration frequency of a fan blade is a fraction of a hertz. To achieve resonance between the target system and the fan blade, the target system requires, in addition to the target element, an elastic element to adjust the target system's natural frequency, ensuring that the difference between the target system's natural frequency and the fan blade's vibration frequency falls within a predetermined range.

[0097] Based on the above, the blade vibration frequency, the natural frequency of the target system, and the resonant frequency of the current in the energy consumption circuit (referred to as the resonant frequency of the energy consumption circuit) can also be made close, that is, Ω≈ω s ≈ω I When the resonant frequency of the current in the energy consumption circuit is close to the vibration frequency of the fan blades, a larger current I can be generated in the energy consumption circuit, and the energy dissipated by the energy consumption device = I 2 R. When the current is larger, the dissipated energy is greater, and the effect of improving the damping of the fan blades is better.

[0098] It can be seen that the energy consumption circuit can only resonate if both inductive and capacitive devices exist in the energy consumption circuit. In order to make Ω≈ω s ≈ω I The damper system in the embodiment of the present application also includes a capacitive device. By changing the resonant frequency of the energy consumption circuit, the difference between the resonant frequency of the energy consumption circuit and the blade vibration frequency can be made to meet the preset range that enables the target system to resonate with the wind turbine blade, that is, Ω≈ω s ≈ω I .

[0099] The preset range in this process can be the same as the preset range satisfied by the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade, which will not be described here. I ∈[0.8×Ω,1.2×Ω] to make the resonance effect of the energy consumption circuit better. I ∈[0.8×Ω,1.2×Ω] is obtained through experiments. This is only an example and is not limited. It can also be determined according to actual conditions. The resonant frequency of the energy consumption circuit can also be understood as the resonant frequency of the current ω I .

[0100] There is a connection path between the energy consumption devices and the inductive devices in the energy consumption circuit and the capacitive devices in the damper system, that is, the energy consumption circuit loop contains not only energy consumption devices and inductive devices but also capacitive devices.

[0101] As an optional example, the number of capacitive devices is one. In this case, the energy consumption circuit of each damper unit is connected to this capacitive device. That is, the entire damper system is connected to one capacitive device.

[0102] As another optional example, there are multiple capacitive devices. In this case, one or more capacitive devices can be connected to the energy consumption circuit of each damper unit. The capacitive devices connected to the energy consumption circuit of some or all of the damper units can be the same capacitive devices or different capacitive devices. For example, the number of capacitive devices is 3, the number of damper units is 3, and each damper unit includes an energy consumption circuit. Then, a capacitive device can be connected to the energy consumption circuit of each damper unit, and the connected capacitive devices are different. In addition, the energy consumption circuit of each damper unit can also be connected to the three capacitive devices, which is not limited here. When a damper unit includes multiple energy consumption circuits, the capacitive devices connected to the multiple energy consumption circuits included in the same damper unit can also be the same capacitive devices or different capacitive devices, which is not limited here.

[0103] As an optional example, the capacitive device may be a capacitive device with an adjustable capacitance value. As another optional example, the capacitive device may be a capacitive device with an unadjustable capacitance value, such as a capacitor composed of two capacitor plates.

[0104] For example, the inductance value of the inductive device and the capacitance value of the capacitive device are adjustable, and the two are used to change the resonant frequency of the energy consumption circuit so that the difference between the resonant frequency of the energy consumption circuit and the blade vibration frequency meets the preset range that enables the target system to resonate with the wind turbine blade.

[0105] Among them, "adjustment" can be understood as when the inductive device and the capacitive device are inductive devices with adjustable inductance and capacitive devices with adjustable capacitance, directly adjusting the inductance value of the inductive device and directly adjusting the capacitance value of the capacitive device; "adjustment" can also be understood as when the inductive device and the capacitive device are inductive devices with non-adjustable inductance and capacitive devices with non-adjustable capacitance, the inductive device and the capacitive device in the damper system can be adjusted, that is, directly selecting an inductive device and a capacitive device, the inductance value of the selected inductive device and the capacitance value of the selected capacitive device can make the difference between the resonant frequency of the energy consumption circuit and the blade vibration frequency meet the preset range that can make the target system resonate with the wind turbine blade.

[0106] Referring to Figure 3, Figure 3 is a schematic diagram of a connection method for an inductive device, an energy dissipation device, and a capacitive device provided in an embodiment of the present application. As shown in Figures 3(a)-3(d), the connection method between the inductive device and the energy dissipation device in the energy dissipation circuit and the capacitive device is any of the following:

[0107] The inductive device, the energy dissipative device and the capacitive device are connected in series;

[0108] The inductive device, the energy dissipative device and the capacitive device are connected in parallel;

[0109] The energy dissipation device is connected in parallel with the capacitive device and then connected in series with the inductive device;

[0110] The energy dissipation device is connected in series with the inductive device and then connected in parallel with the capacitive device.

[0111] As shown in Figure 3(a), the first connection method is to connect the inductive device, energy dissipation device and capacitive device in series. When the energy dissipation circuit resonates, it is series resonance. As shown in Figure 3(b), the second connection method is to connect the inductive device, energy dissipation device and capacitive device in parallel. When the energy dissipation circuit resonates, it is parallel resonance. It can be seen that the resonant frequency formulas in series resonance and parallel resonance are both

[0112] As shown in Figure 3(c), the third connection method is to connect the energy dissipation device and the inductive device in series, and then connect them in parallel with the capacitive device. The resonant frequency formula of the energy dissipation circuit in this connection method is:

[0113] As shown in Figure 3(d), the fourth connection method is to connect the energy dissipation device and the capacitive device in parallel, and then connect them in series with the inductive device. The resonant frequency formula of the energy dissipation circuit in this connection method is:

[0114] It is understandable that when the inductive device, energy dissipation device and capacitive device in the energy dissipation circuit are connected in the third and fourth connection modes, in addition to adjusting the inductance value of the inductive device and the capacitance value of the capacitive device, the resistance value of the energy dissipation device also needs to be adjusted.

[0115] It will also be understood that if the inductive component is a coil, and the energy consumption circuit includes multiple coils, the inductance value L in the above resonant frequency formula is the inductance value obtained by combining the multiple coils as a whole. If the energy consumption component is a resistor, and the energy consumption circuit includes multiple resistors, the resistance value R in the above resonant frequency formula is the resistance value obtained by combining the multiple resistors as a whole. If the capacitive component is a capacitor, and the energy consumption circuit includes multiple capacitors, the capacitance value C in the above resonant frequency formula is the capacitance value obtained by combining the multiple capacitors as a whole.

[0116] From the above, we can see that through Ω≈ω s ≈ω I The setting can make the fan blades resonate with the target system and the energy consumption circuit resonate, so that the target element can vibrate to a large extent through resonance, and relative movement occurs between the inductive device and the magnetic device, so that a large induced current is generated through the resonance of the energy consumption circuit, and a large energy consumption is generated through the energy consumption device, thereby greatly increasing the blade damping.

[0117] Based on the above, the following describes in detail the structures of six damper units. The damper units in a damper system may have any of these structures, or the damper system may include damper units of multiple different structures. First, refer to Figures 4a and 4b, which are schematic diagrams of the structures of a set of damper units provided in an embodiment of the present application.

[0118] As shown in Figures 4a and 4b, in addition to the energy-consuming device 2, the inductive device 6, the magnetic device 3, and the elastic element 5, the damper unit also includes a mounting base 1, a sliding holder 4, and a slide rail 8. Figures 4a and 4b also show the capacitor device 7 that may be included in the damper unit. In Figures 4a and 4b, the energy-consuming devices are all represented by adjustable resistors, the inductive devices are all represented by coils (multiple coils can form a coil group), the magnetic devices are all represented by magnets (multiple magnets can form a magnet group), the elastic elements are all represented by springs, and the capacitor devices are all represented by adjustable capacitors. This is only for example and does not constitute a limitation. When the magnetic device is installed on the sliding holder, the total weight of the magnetic device and the sliding holder in Figures 4a and 4b can be represented as m, the stiffness of the spring is k, and ω s is the natural frequency of the target system, and the number of magnetic devices is N m After testing, N m ≥2.

[0119] As shown in Figures 4a and 4b, the magnets in the magnet assembly are, for example, bar magnets, each having a north pole and an south pole. The same magnetic pole of each magnetic device is oriented in the same direction as that of the adjacent magnetic device, i.e., each magnetic device is arranged identically to the adjacent magnetic devices. It should be understood that the magnets can be other than bar magnets, and this is not a limitation here; they only need to be able to generate a magnetic field.

[0120] The mounting base 1 is used to secure the entire damper system to the wind turbine blade. The sliding retainer 4 is connected to the mounting base 1 via an elastic element 5, and the sliding retainer 4 is capable of sliding on a slide rail 8. As an optional example, if the elastic element is a spring, the spring can be mounted on the slide rail, as shown in Figures 4a and 4b. The sliding retainer 4 is able to slide on the slide rail 8 due to the vibration of the elastic element 5 and the target element after the target system, including the elastic element 5 and the target element, resonates with the wind turbine blade. The vibration direction of the target system is the vibration direction of the target element. It can be seen that the vibration direction of the target element is determined when the vibration direction of the target element and the blade swing direction (i.e., the Y direction) fall within a preset angular range. In practice, the positions of the various structures in the damper unit (such as the mounting base, slide rail, elastic element, sliding retainer, magnetic device, and inductive device) are adjusted so that the vibration direction of the target element and the blade swing direction fall within a preset angular range.

[0121] As shown in Figures 4a and 4b, the inductive devices 6 are all mounted on the mounting base 1, and the position of the inductive devices 6 is fixed. The magnetic devices 3 are all mounted on the sliding holder 4. In this case, the target element is the magnetic device 3. The target system (including the magnetic device 3 and the elastic element 5) is used to drive the sliding holder 4 to reciprocate on the slide rail 8 in the vibration direction of the target element during vibration, and normal relative motion or tangential relative motion occurs between the magnetic device 3 on the sliding holder 4 and the inductive device 6 on the mounting base 1. Therefore, when normal relative motion occurs, the inductive device 6 cuts the magnetic flux lines longitudinally; when tangential relative motion occurs, the inductive device cuts the magnetic flux lines transversely. Whether it is normal relative motion or tangential relative motion, the magnetic flux passing through the inductive device will change, causing an induced current to be generated in the energy consumption circuit.

[0122] The direction of relative motion between the magnetic device 3 and the inductive device 6 is determined by the connection method between the slide rail, the mounting base, and the sliding holder. Figure 4a shows one connection method between the slide rail, the mounting base, and the sliding holder, which allows normal relative motion between the magnetic device 3 and the inductive device 6 when the target system vibrates. Figure 4b shows another connection method between the slide rail, the mounting base, and the sliding holder, which allows lateral relative motion between the magnetic device 3 and the inductive device 6 when the target system vibrates.

[0123] In the embodiment of the present application, the normal direction can be understood as the normal direction of the inductive device or the direction with an interval angle from the normal direction of the inductive device. The interval angle can be an error angle within the allowable range. The error angle is usually small and is not limited here. It can be determined according to actual conditions. The tangential direction can be understood as the tangential direction of the inductive device or the direction with an interval angle from the tangential direction of the inductive device. The interval angle can be an error angle within the allowable range. The error angle is usually small and is not limited here. It can be determined according to actual conditions. When the inductive device 6 is mounted on the mounting base 1 and the magnetic device 3 is mounted on the sliding holder 4, the normal relative motion means that the position of the inductive device is fixed, and the magnetic device (i.e., the target element in this example) moves in the normal direction of the inductive device, so that the inductive device cuts the magnetic flux lines of the magnetic device in the normal direction of the inductive device. At the same time, when the inductive device 6 is installed on the mounting base 1 and the magnetic device 3 is installed on the sliding holder 4, the tangential relative motion means that the position of the inductive device is fixed, and the magnetic device moves in the tangential direction of the inductive device, so that the inductive device cuts the magnetic flux lines of the magnetic device in the tangential direction of the inductive device.

[0124] Specifically, as shown in the specific structure of Figure 4a, the mounting base is exemplified as a four-frame structure, including two long frames and two short frames. Bolt holes are provided on the long frames to fix the mounting base to the fan blades by installing bolts in the bolt holes. When bolt holes are not provided on the mounting base, the mounting base can be pasted on the fan blades. The sliding retaining frame is located between the two long frames of the mounting base and is parallel to the two long frames of the mounting base. The inductive devices can be installed side by side on the two long frames of the mounting base, and the magnetic devices are installed side by side on the sliding retaining frame. For example, the number of inductive devices installed side by side on the two long frames of the mounting base is the same, and the number of inductive devices installed on one long frame is the same as the number of magnetic devices installed side by side on the sliding retaining frame. It can be seen that when the number of inductive devices in the embodiment of the present application is multiple, the multiple inductive devices are connected in parallel to the energy consumption circuit.

[0125] The slide rail includes a first slide rail (the slide rail on the left in Figure 4a) and a second slide rail (the slide rail on the right in Figure 4a), and the slide rails are fixed in position. The elastic element includes a first elastic element (the elastic element on the upper left in Figure 4a), a second elastic element (the elastic element on the upper right in Figure 4a), a third elastic element (the elastic element on the lower left in Figure 4a) and a fourth elastic element (the elastic element on the lower right in Figure 4a). The two ends of the first slide rail are respectively connected (fixed on) the two long frames of the mounting base and pass through the sliding retainer, and the two ends of the second slide rail are also respectively connected (fixed on) the two long frames of the mounting base and pass through the sliding retainer. The sliding retainer is connected to one long frame of the mounting base through the first elastic element and the second elastic element, and the sliding retainer is connected to the other long frame of the mounting base through the third elastic element and the fourth elastic element. The first elastic element and the third elastic element are sleeved on the first slide rail, and the second elastic element and the fourth elastic element are sleeved on the second slide rail. One end of the elastic element is connected to the mounting base, and the other end is connected to the sliding retainer.

[0126] The central axis of each elastic element, the central axis of each inductive device, the central axis of each magnetic device, and the central axis of the slide rail are in the same direction. In this way, the magnetic device can move in the direction of the central axis when in motion, and normal relative motion can occur between the magnetic device and the inductive device. At this time, in order to make the vibration direction of the magnetic device and the swing direction of the blade meet the preset angle range, the central axis direction of the magnetic device needs to meet the preset angle range with the swing direction of the blade. For example, the central axis direction of the magnetic device in Figure 4a can be the Y direction. That is, the central axis of each elastic element, the central axis of each inductive device, and the central axis of each magnetic device are all in the Y direction. In actual applications, the damper unit can be installed on the fan blade according to the constraints in this direction.

[0127] Based on this, the direction in which the inductive devices or magnetic devices are arranged in parallel in Figure 4a can be perpendicular to the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the inductive devices or magnetic devices are arranged in parallel is the Z direction, and the central axis directions of the inductive devices and the magnetic devices are both in the Y direction).

[0128] When the target system resonates with the wind turbine blades, the elastic elements and magnetic components vibrate, driving the sliding cage to reciprocate on the rail in the direction of the magnetic component's vibration. The magnetic components and inductive components on the sliding cage undergo normal relative motion. This subsequently generates an induced current in the energy-consuming circuit. In practice, as shown in Figure 4a, when the first and second elastic elements compress, the third and fourth elastic elements stretch.

[0129] It can be understood that in the structure shown in Figure 4a, the normal direction of the inductive device is the Y direction, and the tangential direction of the inductive device is the Z direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the central axis of the coil (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis direction. As shown in Figure 4a, the vibration direction / movement direction of the magnet group is the Y direction, and the central axis and normal direction of the coil group are also the Y direction. When the magnet group vibrates in the Y direction, the coil group cuts the magnetic flux lines of the magnetic device in the Y direction (the normal direction of the coil). That is, the magnet group moves relative to the normal direction of the coil group along the Y direction through the spring, causing the magnetic flux to change to generate an induced current.

[0130] Referring again to the specific structure shown in Figure 4b, the installation position relationship of the mounting base, sliding holder, inductive device, and magnetic device in Figure 4b is the same as that in Figure 4a, but the installation position relationship of the slide rail and the elastic element is different from that in Figure 4a. Specifically, the elastic element includes a first elastic element (the elastic element on the left side in Figure 4b) and a second elastic element (the elastic element on the right side in Figure 4b). The slide rail is fixed in position, and the two ends of the slide rail are connected to the two short frames of the mounting base, and there is a through hole running through the center axis direction of the sliding holder, and the slide rail runs through the through hole in the center axis direction of the sliding holder. One end of the first elastic element is connected to a short frame of the mounting base, the other end of the first elastic element is connected to one end in the center axis direction of the sliding holder, one end of the second elastic element is connected to another short frame of the mounting base, and the other end of the second elastic element is connected to the other end in the center axis direction of the sliding holder.

[0131] Based on the above structure, the central axis of each inductive component is oriented in the same direction as the central axis of each magnetic component. The central axis of each elastic element and the central axis of the slide rail are also oriented in the same direction. Furthermore, the central axis of the magnetic component and the central axis of the elastic element are perpendicular to each other. This allows the magnetic component to move tangentially to the central axis of the magnetic component during movement, allowing tangential relative motion between the magnetic component and the inductive component. In this case, in order for the vibration direction of the magnetic component and the blade swing direction to fall within a preset angular range, the tangential direction of the central axis of the magnetic component must fall within a preset angular range with the blade swing direction. For example, the central axis of the magnetic component in Figure 4a can be in the Z direction. That is, the central axis of each inductive component and each magnetic component are oriented in the Z direction. The central axis of each elastic element and the central axis of the slide rail are oriented in the Y direction. In practical applications, the damper unit can be installed on the wind turbine blade according to this directional constraint.

[0132] Based on this, the direction in which the inductive device or the magnetic device is arranged in parallel in Figure 4b can be the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the inductive device or the magnetic device is arranged in parallel is the Y direction, and the central axis direction of the inductive device and the magnetic device is the Z direction). When the target system resonates with the fan blades, the various elastic elements and magnetic devices vibrate, driving the sliding holder to reciprocate on the slide rail in the vibration direction of the magnetic device, and the magnetic device and the inductive device on the sliding holder move relative to each other in the tangential direction. As a result, an induced current will be generated in the energy consumption circuit later. In actual application, as shown in Figure 4b, when the first elastic element is compressed, the second elastic element is stretched.

[0133] In the structure shown in Figure 4b, the normal direction of the inductive device is the Z direction, and the tangential direction of the inductive device is the Y direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the coil's central axis (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis. As shown in Figure 4b, the vibration direction / movement direction of the magnet group can be the Y direction, and the tangential direction of the coil is the Y direction. Then, when the magnet group vibrates in the Y direction, the coil cuts the magnetic flux lines of the magnetic device in the Y direction (the tangential direction of the coil). That is, the magnet group moves relative to the coil group in the tangential direction along the Y direction through the spring, causing a change in magnetic flux and generating an induced current.

[0134] Referring to FIG4b again, due to the tangential relative motion between the inductive device and the magnetic device, when the inductive device is a coil and the magnetic device is a bar magnet, the bar magnet will not pass through the coil. Therefore, a magnetic core can be provided in the middle of the coil to increase the magnetic flux.

[0135] 5a and 5b , which are schematic diagrams of a three-dimensional structure of a damper unit provided in an embodiment of the present application, and specifically a three-dimensional schematic diagram of the structure shown in FIG4b .

[0136] As shown in Figures 5a and 5b, the damper unit includes a mounting base 1, a magnet 3, a spring 5, a coil 6, a slide rail 8, a magnet holder 110, a spring holder 111, a slider 112, and a coil holder 113. The variable resistor and capacitor, which are part of the same energy-consuming circuit as the coil, are not shown. In this actual structure, magnet holder 110 and slider 112 correspond to slide holder 4 in Figure 4b.

[0137] The magnet 3 is mounted on the slider 112 via the magnet fixing frame 110. The slider 112 moves laterally on the slide rail 8. The magnet fixing frame 110 is connected to the spring fixing frame 111 via the spring 5. The coil groups on both sides are connected to the mounting base 1 via the coil fixing frame 113. The number of coils 6 is N. wMultiple coils 6 form a coil assembly. To increase the magnet's damping effect within a stroke, multiple coils can be used to increase the energy dissipation of the induced current. At this point, the coil assembly is fixed in position, and the magnet 3, through the spring 5, moves tangentially relative to the coil assembly, causing a change in magnetic flux to generate an induced current.

[0138] It is understandable that FIG. 5 a and FIG. 5 b are merely schematic diagrams of three-dimensional structures for illustration and are not intended to be limiting.

[0139] Referring to FIG. 6 a and FIG. 6 b , FIG. 6 a and FIG. 6 b are schematic structural diagrams of another group of damper units provided in an embodiment of the present application.

[0140] As shown in Figures 6a and 6b, in addition to the energy-consuming device 2, the inductive device 6, the magnetic device 3, and the elastic element 5, the damper unit also includes a mounting base 1, a sliding retainer 4, and a slide rail 8. Figures 6a and 6b also show a capacitor device 7 that may be included in the damper unit. In Figures 6a and 6b, the energy-consuming devices are all represented by adjustable resistors, the inductive devices are all represented by coils (multiple coils can form a coil group), the magnetic devices are all represented by magnets (multiple magnets can form a magnet group), the elastic elements are all represented by springs, and the capacitor devices are all represented by adjustable capacitors. This is for illustrative purposes only and does not constitute a limitation.

[0141] As shown in Figures 6a and 6b, the magnets in the magnet assembly are, for example, bar magnets, each having a north pole and an south pole. The same magnetic pole of each magnetic device is oriented in the same direction as that of the adjacent magnetic device, i.e., each magnetic device is arranged identically to the adjacent magnetic devices. It should be understood that the magnets may be other than bar magnets, and this is not a limitation here; they only need to be able to generate a magnetic field.

[0142] The mounting base 1 is used to secure the entire damper system to the wind turbine blade. The sliding retainer 4 is connected to the mounting base 1 via an elastic element 5, and the sliding retainer 4 is capable of sliding on a slide rail 8. As an optional example, if the elastic element is a spring, the spring can be mounted on the slide rail, as shown in Figures 6a and 6b. The sliding retainer 4 is able to slide on the slide rail 8 due to the vibration of the elastic element 5 and the target element after the target system, including the elastic element 5 and the target element, resonates with the wind turbine blade. The vibration direction of the target system is the vibration direction of the target element. It can be seen that the vibration direction of the target element is determined when the vibration direction of the target element and the blade swing direction (i.e., the Y direction) fall within a preset angular range. In practice, the positions of various structures in the damper unit (such as the mounting base, slide rail, elastic element, sliding retainer, magnetic device, and inductive device) are adjusted so that the vibration direction of the target element and the blade swing direction fall within a preset angular range.

[0143] As shown in Figures 6a and 6b, the magnetic devices 3 are all mounted on the mounting base 1, and the inductive devices 6 are fixed in position. The inductive devices 6 are all mounted on the sliding holder 4. In this case, the target element is the inductive device 6. The target system (including the inductive device 6 and the elastic element 5) is used to drive the sliding holder 4 to reciprocate on the slide rail 8 in the vibration direction of the target element during vibration, and normal relative motion or tangential relative motion occurs between the inductive device 6 on the sliding holder 4 and the magnetic device 3 on the mounting base 1. Therefore, when normal relative motion occurs, the inductive device 6 cuts the magnetic flux lines longitudinally; when tangential relative motion occurs, the inductive device cuts the magnetic flux lines transversely. Whether it is normal relative motion or tangential relative motion, the magnetic flux passing through the inductive device will change, causing an induced current to be generated in the energy consumption circuit.

[0144] The direction of relative motion between the magnetic device 3 and the inductive device 6 is determined by the connection method between the slide rail, the mounting base, and the sliding holder. Figure 6a shows one connection method between the slide rail, the mounting base, and the sliding holder, which allows normal relative motion between the inductive device 6 and the magnetic device 3 when the target system vibrates. Figure 6b shows another connection method between the slide rail, the mounting base, and the sliding holder, which allows lateral relative motion between the inductive device 6 and the magnetic device 3 when the target system vibrates.

[0145] Specifically, as shown in Figure 6a, the sliding retainer has a four-frame structure, including two long frames and two short frames. The mounting base is located between and parallel to the two long frames of the sliding retainer. The mounting base is provided with bolt holes, which are used to secure the mounting base to the wind turbine blade by installing bolts in the bolt holes. If the mounting base does not have bolt holes, the mounting base can be glued to the wind turbine blade.

[0146] The inductive components can be mounted in parallel on the two long sides of the sliding holder, and the magnetic components can be mounted in parallel on the sliding holder. For example, the number of inductive components mounted in parallel on the two long sides of the sliding holder is the same, and the number of inductive components mounted on one long side is the same as the number of magnetic components mounted in parallel on the mounting base. It can be seen that when there are multiple inductive components in the embodiments of the present application, the multiple inductive components are connected in parallel to the energy consumption circuit.

[0147] The slide rail includes a first slide rail (the slide rail on the left side in Figure 6a) and a second slide rail (the slide rail on the right side in Figure 6a), and the slide rails are fixed in position. The elastic element includes a first elastic element (the elastic element on the upper left in Figure 6a), a second elastic element (the elastic element on the upper right in Figure 6a), a third elastic element (the elastic element on the lower left in Figure 6a) and a fourth elastic element (the elastic element on the lower right in Figure 6a). The two ends of the first slide rail respectively pass through the two long frames of the sliding holder, and the middle of the slide rail is fixed on the mounting base. The two ends of the second slide rail also respectively pass through the two long frames of the sliding holder, and the middle of the slide rail is fixed on the mounting base. The mounting base is connected to one long frame of the sliding holder through the first elastic element and the second elastic element, and the mounting base is connected to the other long frame of the sliding holder through the third elastic element and the fourth elastic element. The first elastic element and the third elastic element are sleeved on the first slide rail, and the second elastic element and the fourth elastic element are sleeved on the second slide rail. One end of the elastic element is connected to the mounting base, and the other end is connected to the sliding holder.

[0148] The central axis of each elastic element, the central axis of each inductive device, the central axis of each magnetic device, and the central axis of the slide rail are all in the same direction. This allows the inductive device to move in the direction of the central axis during movement, and normal relative motion can occur between the inductive device and the magnetic device. At this time, in order to ensure that the vibration direction of the inductive device and the blade swing direction meet the preset angle range, the central axis direction of the inductive device needs to meet the preset angle range with the blade swing direction. For example, the central axis direction of the inductive device in Figure 6a can be the Y direction. That is, the central axis of each elastic element, the central axis of each inductive device, and the central axis of each magnetic device are all in the Y direction. In actual applications, the damper unit can be installed on the wind turbine blade according to the constraints in this direction.

[0149] Based on this, the direction in which the inductive devices or magnetic devices are arranged in parallel in Figure 6a can be a direction perpendicular to the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the inductive devices or magnetic devices are arranged in parallel is the Z direction, and the central axis directions of the inductive devices and the magnetic devices are both in the Y direction).

[0150] When the target system resonates with the wind turbine blades, the elastic elements and inductive components vibrate, driving the sliding cage to reciprocate on the rail in the direction of the inductive component's vibration. This causes the inductive component on the sliding cage to move normal relative to the magnetic component. This subsequently generates an induced current in the energy-consuming circuit. In practice, as shown in Figure 6a, when the first and second elastic elements compress, the third and fourth elastic elements stretch.

[0151] It can be understood that in the structure shown in Figure 6a, the normal direction of the inductive device is the Y direction, and the tangential direction of the inductive device is the Z direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the central axis of the coil (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis direction. As shown in Figure 6a, the vibration direction / movement direction of the coil group is the Y direction, and the central axis and normal direction of the coil group are also the Y direction. When the coil group vibrates in the Y direction, the coil group cuts the magnetic flux lines of the magnetic device in the Y direction (the normal direction of the coil). That is, the coil group moves relative to the normal direction of the magnet group along the Y direction, causing a change in magnetic flux to generate an induced current.

[0152] Referring again to the specific structure shown in Figure 6b, the installation position relationship of the mounting base, sliding holder, inductive device, and magnetic device in Figure 6b is the same as that in Figure 6a, but the installation position relationship of the slide rail and the elastic element is different from that in Figure 6a. Specifically, the elastic element includes a first elastic element (the elastic element on the left side of Figure 6b) and a second elastic element (the elastic element on the right side of Figure 6b). The slide rail includes a first slide rail (the slide rail on the left side of Figure 6b) and a second slide rail (the slide rail on the right side of Figure 6b), and the slide rail position is fixed. One end of the first slide rail is connected to one end of the mounting base, and the other end of the first slide rail passes through a short frame of the sliding holder; one end of the second slide rail is connected to the other end of the mounting base, and the other end of the second slide rail passes through another short frame of the sliding holder. One end of the first elastic element is connected to one end of the mounting base, and the other end of the first elastic element is connected to a short frame of the sliding holder, one end of the second elastic element is connected to the other end of the mounting base, and the other end of the second elastic element is connected to another short frame of the sliding holder.

[0153] Based on the above structure, the central axis of each inductive component is oriented in the same direction as the central axis of each magnetic component. The central axis of each elastic element and the central axis of the slide rail are also oriented in the same direction. Furthermore, the central axis of the inductive component is perpendicular to the central axis of the elastic element. This allows the inductive component to move tangentially to the central axis of the inductive component during movement, enabling tangential relative motion between the inductive component and the magnetic component. In this case, to ensure that the vibration direction of the inductive component and the blade swing direction fall within a preset angular range, the tangential direction of the central axis of the inductive component must fall within a preset angular range relative to the blade swing direction. For example, the central axis of the inductive component in Figure 6a can be oriented in the Z direction. That is, the central axis of each inductive component and the central axis of each magnetic component are oriented in the Z direction. The central axis of each elastic element and the central axis of the slide rail are oriented in the Y direction. In practical applications, the damper unit can be installed on the wind turbine blade according to this directional constraint.

[0154] Based on this, the direction in which the inductive devices or magnetic devices are arranged in parallel in Figure 6b can be the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the inductive devices or magnetic devices are arranged in parallel is the Y direction, and the central axis directions of the inductive devices and magnetic devices are both the Z direction). When the target system resonates with the fan blades, each elastic element and inductive device vibrates, driving the sliding holder to reciprocate on the slide rail in the vibration direction of the inductive device, and the inductive device and the magnetic device on the sliding holder move relative to each other in the tangential direction. As a result, an induced current will be generated in the energy consumption circuit later. In actual application, as shown in Figure 4b, when the first elastic element is compressed, the second elastic element is stretched.

[0155] In the structure shown in Figure 6b, the normal direction of the inductive device is the Z direction, and the tangential direction of the inductive device is the Y direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the coil's central axis (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis. As shown in Figure 6b, the vibration / movement direction of the coil group can be the Y direction, and the tangential direction of the coil is the Y direction. Then, when the coil group vibrates in the Y direction, the coil cuts the magnetic flux lines of the magnetic device in the Y direction (the tangential direction of the coil). In other words, the tangential relative motion of the coil group and the magnet group along the Y direction causes a change in magnetic flux, generating an induced current. Referring again to Figure 6b, due to the tangential relative motion between the inductive device and the magnetic device, when the inductive device is a coil and the magnetic device is a bar magnet, the bar magnet will not pass through the coil. Therefore, a magnetic core can be placed in the middle of the coil to increase the magnetic flux.

[0156] In the various damper unit structures described above, the magnetic poles of the multiple magnetic components are oriented in the same direction, and a predetermined distance separates each two magnetic components. It will be appreciated that when the magnetic poles of the multiple magnetic components are oriented in the same direction, the spacing between adjacent magnetic components can be appropriately adjusted to prevent repulsion between like-pole magnetic poles. As can be seen, if the number of magnetic components remains constant, the larger the spacing, the more space the damper unit occupies. The spacing can be determined based on actual needs.

[0157] Referring to FIG. 7 a - FIG. 7 b , FIG. 7 a - FIG. 7 b are schematic structural diagrams of another group of damper units provided in an embodiment of the present application.

[0158] As shown in Figures 7a and 7b, in addition to the energy-absorbing device 2, the inductive device 6, the magnetic device 3, and the elastic element 5, the damper unit also includes a mounting base 1, a sliding retainer 4, a slide rail 8, and a magnetic device kit 9. The magnetic device kit 9 ​​is mounted on the magnetic device 3, and the inductive device 6 is mounted on the magnetic device kit 9. The mounting base 1 is used to be fixed to the wind turbine blade; the sliding retainer 4 is connected to the mounting base 1 via the elastic element 5. For example, when the inductive device 6 is a coil, the coil can be wound around the magnetic device kit 9. The magnet assembly outer shell 9 is made of a magnetic conductive material, such as copper, and is a thin cylindrical structure with a hollow interior.

[0159] As can be seen, since the magnetic device assembly 9 is mounted on the magnetic device 3 and the inductive device 6 is mounted on the magnetic device assembly 9, the inductive and magnetic devices can only undergo normal relative motion. The magnetic device can be mounted on a sliding holder or a mounting base. When the magnetic device is mounted on the sliding holder, the target element is a magnetic device, and the inductive device and the magnet assembly outer shell are fixed in position, as shown in Figure 7a. In the structure shown in Figure 7a, for example, the magnet assembly outer shell can be connected to the mounting base. When the magnetic device is mounted on the mounting base, the target element is an inductive device, and the magnetic device is fixed in position, as shown in Figure 7b. In the structure shown in Figure 7b, for example, the magnet assembly outer shell can be connected to the sliding holder. When the target system vibrates, it drives the sliding holder to reciprocate on the slide rail in the direction of the target element's vibration, causing the magnetic and inductive devices to undergo normal relative motion, with the magnetic device penetrating longitudinally and cutting the magnetic flux lines. As can be seen, when the target element is an inductive device, the inductive device and the magnet assembly outer shell move together.

[0160] As shown in the specific structure of Figure 7a, the mounting base is an example of a four-frame structure, including two long frames and two short frames. Bolt holes are provided on the long frames to fix the mounting base to the wind turbine blades by installing bolts in the bolt holes. When no bolt holes are provided on the mounting base, the mounting base can be adhered to the wind turbine blades. The sliding retaining frame is located between the two long frames of the mounting base and is parallel to the two long frames of the mounting base. The magnetic components are mounted in parallel on the sliding retaining frame. The magnet group outer sleeve is provided on the outside of the sliding retaining frame. As shown in Figure 7a, the energy consumption circuit includes an inductive component, a variable capacitor and a variable resistor connected in series.

[0161] Specifically, the elastic element includes a first elastic element (the elastic element on the left side of Figure 7a) and a second elastic element (the elastic element on the right side of Figure 7a). The slide rail is fixed in position, with both ends of the slide rail connected to the two short side frames of the mounting base. A through hole is provided in the direction of the central axis of the sliding holder, and the slide rail passes through the through hole in the direction of the central axis of the sliding holder. One end of the first elastic element is connected to a short side frame of the mounting base, and the other end of the first elastic element is connected to one end in the direction of the central axis of the sliding holder. One end of the second elastic element is connected to the other short side frame of the mounting base, and the other end of the second elastic element is connected to the other end in the direction of the central axis of the sliding holder.

[0162] Based on the above structure, the central axis of the inductive component, the central axis of each magnetic component, the central axis of each elastic element, and the central axis of the slide rail are all oriented in the same direction. This allows the magnetic component to move in the direction of its central axis during movement, allowing normal relative motion between the magnetic component and the inductive component. At this point, in order for the vibration direction of the magnetic component to fall within a preset angular range with the blade swing direction, the central axis of the magnetic component must also fall within a preset angular range with the blade swing direction. For example, the central axis of the magnetic component in Figure 7a can be oriented in the Y direction. In practical applications, the damper unit can be installed on the wind turbine blade according to this directional constraint.

[0163] Based on this, the direction in which the magnetic devices are arranged in parallel in Figure 7a can be the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the magnetic devices are arranged in parallel is the Y direction). When the target system resonates with the fan blades, the various elastic elements and magnetic devices vibrate, driving the sliding holder to reciprocate on the slide rail in the vibration direction of the magnetic device, and the magnetic device and the inductive device on the sliding holder undergo relative movement in the normal direction. As a result, an induced current will subsequently be generated in the energy consumption circuit. In actual application, as shown in Figure 7a, when the first elastic element is compressed, the second elastic element is stretched.

[0164] In the structure shown in Figure 7a, the normal direction of the inductive device is the Y direction, and the tangential direction of the inductive device is the Z direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the coil's central axis (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis. As shown in Figure 7a, the vibration direction / movement direction of the magnet group can be the Y direction, and the tangential direction of the coil is the Z direction. Then, when the magnet group vibrates in the Y direction, the coil cuts the magnetic flux lines of the magnetic device in the Y direction (the normal direction of the coil). That is, the magnet group moves relative to the coil along the Y direction through the spring, causing a change in magnetic flux and generating an induced current.

[0165] As shown in Figure 7b, the sliding retainer has a four-frame structure, including two long frames and two short frames. The mounting base is located between and parallel to the two long frames of the sliding retainer. Bolt holes are provided on the mounting base for securing the mounting base to the wind turbine blade by installing bolts in the bolt holes. If the mounting base does not have bolt holes, the mounting base can be glued to the wind turbine blade.

[0166] The elastic element includes a first elastic element (the elastic element on the left side of Figure 7b) and a second elastic element (the elastic element on the right side of Figure 7b). The slide rail includes a first slide rail (the slide rail on the left side of Figure 7b) and a second slide rail (the slide rail on the right side of Figure 7b), and the slide rails are fixed in position. One end of the first slide rail is connected to one end of the mounting base, and the other end of the first slide rail passes through a short frame of the sliding holder; one end of the second slide rail is connected to the other end of the mounting base, and the other end of the second slide rail passes through the other short frame of the sliding holder. One end of the first elastic element is connected to one end of the mounting base, and the other end of the first elastic element is connected to a short frame of the sliding holder, one end of the second elastic element is connected to the other end of the mounting base, and the other end of the second elastic element is connected to the other short frame of the sliding holder.

[0167] Based on the above structure, the central axis of the inductive device, the central axes of each magnetic device, the central axes of each elastic element, and the central axis of the slide rail are all oriented in the same direction. This allows the inductive device to move in the direction of its central axis, enabling normal relative motion between the inductive device and the magnetic device. To ensure that the vibration direction of the inductive device and the blade swing direction fall within a predetermined angular range, the central axis of the inductive device must fall within a predetermined angular range. For example, the central axis of the magnetic device in Figure 7b can be oriented in the Y direction. In practical applications, the damper unit can be mounted on the wind turbine blade according to this directional constraint.

[0168] Based on this, the direction in which the magnetic devices are arranged in parallel in Figure 7b can be the vibration direction of the target system (for example, when the vibration direction of the target system is the Y direction, the direction in which the magnetic devices are arranged in parallel is the Y direction). When the target system resonates with the fan blades, the various elastic elements and inductive devices vibrate, driving the sliding holder to reciprocate on the slide rail in the vibration direction of the inductive device, and the magnetic device and the inductive device on the sliding holder undergo relative movement in the normal direction. As a result, an induced current will subsequently be generated in the energy consumption circuit. In actual application, as shown in Figure 7b, when the first elastic element is compressed, the second elastic element is stretched.

[0169] In the structure shown in Figure 7b, the normal direction of the inductive device is the Y direction, and the tangential direction of the inductive device is the Z direction. When the inductive device is a coil, the normal direction of the coil can be understood as the direction of the central axis of the coil (such as the x direction in Figure 1, which is the central axis direction), and the tangential direction of the coil is the direction perpendicular to the central axis direction. As shown in Figure 7b, the vibration direction / movement direction of the coil can be the Y direction, and the tangential direction of the coil is the Z direction. Then, when the coil vibrates in the Y direction, the coil cuts the magnetic flux lines of the magnetic device in the Y direction (the normal direction of the coil). That is, the coil undergoes normal relative motion with the internal magnet group along the Y direction through the spring to cause a change in magnetic flux and generate an induced current.

[0170] It can be understood that the composition structure of the damper unit shown above satisfies the formulas involved in the embodiments of the present application.

[0171] In practical applications, the number of inductive components in the energy dissipation circuit can be pre-set. Specifically, the number of inductive components in the energy dissipation circuit satisfies a predetermined range such that the energy generated in the energy dissipation circuit and the kinetic energy work generated in the damper unit together meet a predetermined condition. For example, the ratio of the energy generated in the energy dissipation circuit to the kinetic energy work generated in the damper unit can be determined as an energy ratio. Based on this, the predetermined condition can be, for example, that the energy ratio is greater than a ratio threshold.

[0172] The energy generated in the energy consumption circuit is obtained based on the work done by the induced current in the energy consumption circuit and the self-inductance magnetic energy of the coil in the energy consumption circuit. For example, the energy generated in the energy consumption circuit is the sum of the work done by the induced current in the energy consumption circuit and the self-inductance magnetic energy of the coil in the energy consumption circuit.

[0173] Based on the above, the number of inductive devices (such as coils) is expressed as N w In one working stroke, the energy generated in the energy consumption circuit is The work done by the induced current is The self-inductance of the coil is It can be seen that the work done by the induced current in the energy consumption circuit and the self-inductance magnetic energy of the coil in the energy consumption circuit are both related to the number of inductive components in the energy consumption circuit. In one working stroke, the kinetic energy work generated in the damper unit is W mag =0.5m1v 2 . Where m1 is the sum of the masses of all moving components. For example, as shown in Figure 5b, the magnet, magnet holder, and slider are the moving components, then m1 is the sum of the total masses of the magnet, magnet holder, and slider, and v is the maximum speed of the moving component. When the energy ratio W c / W mag When the resistance is ≥10%, the vibration reduction device will increase the damping effect. If it is less than 10%, it can be increased by increasing Nw To increase the energy generated in the energy consumption circuit, 10% is the percentage threshold.

[0174] In practical applications, the number of damper units can also be pre-set. Specifically, the number of damper units satisfies a range such that the work performed by the damper system is greater than the aerodynamic damping work performed by the wind turbine blades. The work performed by the damper system is derived from the work performed by each damper unit in the damper system. For example, the work performed by the damper system is the sum of the work performed by each damper unit in the damper system.

[0175] The work done by the damper unit is obtained according to the mass of the damper unit and the vibration speed of the fan blade, and the aerodynamic damping work done by the fan blade is obtained according to the blade aerodynamic negative damping of the fan blade and the vibration speed of the fan blade.

[0176] Specifically, the number of damper units is represented as N c If the fan blade vibrates in its natural vibration mode, the amplitude of the fan blade is A e (r), the vibration speed is The aerodynamic damping of the fan blade is negative in this mode, so within one vibration stroke, the aerodynamic damping work of the fan blade is Among them, e represents the negative aerodynamic damping of the blade. Under this amplitude, the work done by the damper system is In this formula, m is the weight of the damper system. So, choose the appropriate N c To ensure that the work done by the damper system is greater than the work done by the aerodynamic damping of the fan blades, so as to increase the damping of the fan blades, reduce the amplitude of the fan blades, reduce the vibration speed of the fan blades, and alleviate the swing of the fan blades.

[0177] In practical applications, according to experiments, the number of damper units N c ∈[1,20]. The number of coils in the damper unit N w ∈[1,20].

[0178] Based on the wind blade provided in the above method embodiment, the embodiment of the present application also provides a wind blade production method applied to the wind blade described in any of the above embodiments. The wind blade production method of the wind blade will be described below in conjunction with the accompanying drawings.

[0179] Refer to Figure 8, which is a flow chart of a method for producing a fan blade according to an embodiment of the present application. As shown in Figure 8, the method includes S801-S805:

[0180] S801: Obtaining the vibration frequency of the fan blades;

[0181] S802: Determine the natural frequency of a target system based on the blade vibration frequency and frequency deviation range of the wind turbine blade, and select an elastic element based on the natural frequency of the target system; the target system includes the elastic element and a target element; the target element is an inductive element or a magnetic element;

[0182] S803: Setting a movable direction of the target element in the damper unit and a blade swing direction of the fan blade to satisfy a preset angle range;

[0183] S804: providing an energy consumption circuit as a loop including an energy consumption device and the inductive device connected thereto, and providing a damper unit including the energy consumption circuit, the magnetic device, and the elastic element;

[0184] S805: A damper system is set on the fan blade, wherein the damper system includes a damper unit arranged in the span direction of the fan blade or a plurality of damper units arranged in parallel and spaced apart, so that the target system in the damper unit resonates with the fan blade, so that relative movement occurs between the magnetic device and the inductive device in the damper unit.

[0185] In a possible implementation, selecting an elastic element according to the natural frequency of the target system includes:

[0186] The stiffness coefficient of the elastic element is determined according to the natural frequency of the target system, and the elastic element is selected according to the stiffness coefficient of the elastic element.

[0187] As an optional example, the damper system further includes a capacitive device; and the method further includes:

[0188] Determining the resonant frequency of the energy consumption circuit according to the blade vibration frequency and frequency deviation range of the fan blade, and selecting the inductive device and the capacitive device according to the resonant frequency of the energy consumption circuit;

[0189] The energy consumption device and the inductive device in the energy consumption circuit are connected to the capacitive device.

[0190] In a possible implementation, selecting the inductive device and the capacitive device according to the resonant frequency of the energy consumption circuit includes:

[0191] determining an inductance value and a capacitance value according to a resonant frequency of the energy consumption circuit;

[0192] The inductive component is selected according to the inductance value, and the capacitive component is selected according to the capacitance value.

[0193] As an optional example, the damper system is provided on the fan blade, comprising:

[0194] determining a blade shimmy vibration mode of the fan blade;

[0195] Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode;

[0196] Arranging the damper system on the fan blade according to a distance between the damper system and the tip of the fan blade and a predetermined condition; the predetermined condition is that the damper system is installed at a non-modal node of the fan blade;

[0197] Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode includes:

[0198] When the blade shimmy vibration mode is a first-order shimmy vibration, determining that the distance between the damper system and the tip of the fan blade is a first distance value;

[0199] When the blade shimmy vibration mode is a second-order shimmy vibration, determining the distance between the damper system and the tip of the fan blade to be a second distance value;

[0200] The first distance value is smaller than the second distance value.

[0201] It can be understood that the fan blade production method provided in this embodiment can be applied to produce the fan blades in the above embodiments. The description of the relevant functions and principles of the fan blades can be found in the above embodiments and will not be repeated here.

[0202] In practical applications, blades can be produced according to the wind turbine blade production method described in the above embodiment. For example, a wind turbine blade having a length of 90 m exhibits negative damping within a wind speed range of 11-13 m / s. The vibration response amplitude of the blade in the swing direction is relatively large within this wind speed range. Furthermore, the vibration mode of the blade is first-order swing, and the blade vibration frequency is 0.5 Hz. Strong self-excited vibrations can reduce the operating life of the wind turbine equipment.

[0203] Taking the structure shown in Figure 4a as an example, the vibration mode of the fan blade is first-order swing vibration, and the damper system can be installed near the front 1 / 3 of the blade, d1 = 10m, d2 = 20m. In order to provide a sufficiently large damping force for the fan blade, the number of damper units in the damper system is selected as N c = 10, set N in each damper unit m = 20 magnets. The parameters of each magnet are as follows: residual magnetic density B r =1.32T, the volume of a single magnet v = 2×10 -6 m 3The total weight of the magnet group and the sliding cage is m = 2.5 kg. The natural frequency of the target system needs to be the same as the blade vibration frequency, so the elastic element stiffness coefficient is selected as k = 35 N·m -1 When the blade vibration frequency reaches 0.5 Hz, the resonant damping unit acts as a dynamic vibration absorber for the blade, causing the fan blade and damper system to resonate. To resonate the energy consumption circuit and ensure that the resonant frequency is consistent with the blade vibration frequency and the natural frequency of the target system, L = 2.84e-5H, C = 3560F, and R = 1Ω are selected.

[0204] See Figure 9, which is a schematic diagram of a blade damping ratio according to an embodiment of the present application. After installing a damper system in a wind turbine blade, the variation of the blade's damping ratio at various wind speeds is shown in Figure 9. As can be seen from Figure 9, without the damper system, the blade exhibits negative damping in the wind speed range of 11-13 m / s. With the damper system installed, the negative damping range disappears, improving the stability of the wind turbine generator set.

[0205] In a possible implementation, an embodiment of the present application further provides a wind turbine, which includes the wind turbine blades described in any one of the above embodiments.

[0206] In a possible implementation, an embodiment of the present application further provides a damper system, the damper system including a damper unit arranged in a target direction of a target object or a plurality of damper units arranged in parallel and spaced apart;

[0207] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0208] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0209] The movable direction of the target element in the damper unit and the vibration direction of the target object satisfy a preset angle range; wherein the target element is the inductive device or the magnetic device; the vibration direction and the target direction are perpendicular to each other;

[0210] The elastic element and the target element are elements in a target system; the difference between the natural frequency of the target system and the vibration frequency of the target object satisfies a preset range that enables the target system and the target object to resonate, so that the target system and the target object resonate, causing relative movement between the magnetic device and the inductive device.

[0211] The target object may be a fan blade, and the target direction may be the span direction of the fan blade, which is not limited here and may be determined according to the actual application scenario of the damper system.

[0212] As an optional example, the damper system further includes a capacitive device, and a connection path is provided between the energy consumption device, the inductive device and the capacitive device in the energy consumption circuit.

[0213] As an optional example, the damper unit in the damper system may be the damper unit shown in FIG. 4 a to FIG. 7 b of the embodiments of the present application, which is not limited here.

[0214] It is understandable that the description of the relevant functions and principles of the damper system provided in this embodiment can be found in the above embodiments and will not be repeated here.

[0215] Through the description of the above embodiments, it can be seen that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the methods described in each embodiment of the present application or certain parts of the embodiments.

[0216] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. The methods disclosed in the embodiments are described briefly because they correspond to the systems disclosed in the embodiments. For relevant details, refer to the description of the systems.

[0217] It should also be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0218] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fan blade, wherein: The fan blade is provided with a damper system; the damper system comprises a damper unit arranged in the span direction of the fan blade or a plurality of damper units arranged in parallel and at intervals; The damper unit includes an energy consumption circuit, a magnetic device and an elastic element; The energy consumption circuit is a loop including connected energy consumption devices and inductive devices; The movable direction of the target element in the damper unit and the blade swing direction of the fan blade satisfy a preset angle range; wherein the target element is the inductive device or the magnetic device; The elastic element and the target element are elements in a target system; the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade satisfies a preset range that enables the target system and the fan blade to resonate, so that the target system and the fan blade resonate, causing relative movement between the magnetic device and the inductive device.

2. The fan blade according to claim 1, wherein: The elastic element stiffness coefficient of the elastic element is adjustable, which is used to change the natural frequency of the target system so that the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade satisfies a preset range that enables the target system to resonate with the fan blade.

3. The fan blade according to claim 1, wherein: The damper system further comprises a capacitive device; a connection path is provided between the energy consumption device, the inductive device and the capacitive device in the energy consumption circuit; and The inductance value of the inductive device and the capacitance value of the capacitive device are adjustable, and the two are used to change the resonant frequency of the energy consumption circuit so that the difference between the resonant frequency of the energy consumption circuit and the blade vibration frequency satisfies the preset range that enables the target system to resonate with the wind turbine blade.

4. The wind turbine blade according to claim 1, wherein: The damper unit further comprises a mounting base, a sliding retainer and a slide rail; the mounting base is fixed on the fan blade; the sliding retainer is connected to the mounting base through the elastic element; The inductive device is mounted on the mounting base, the magnetic device is mounted on the sliding holder, and the target element is the magnetic device; the target system is used to drive the sliding holder to reciprocate on the slide rail in the vibration direction of the target element when vibrating. This allows normal relative motion or tangential relative motion to occur between the magnetic device and the inductive device.

5. The wind turbine blade according to claim 1, wherein: The damper unit further comprises a mounting base, a sliding retainer and a slide rail; the mounting base is fixed on the fan blade; the sliding retainer is connected to the mounting base through the elastic element; The inductive device is mounted on the sliding holder, the magnetic device is mounted on the mounting base, and the target element is the inductive device; the target system is used to drive the sliding holder to reciprocate on the slide rail in the vibration direction of the target element when vibrating, so that normal relative motion or tangential relative motion occurs between the magnetic device and the inductive device.

6. The wind turbine blade according to claim 1, wherein: The damper unit further comprises a mounting base, a sliding holder, a slide rail and a magnetic device kit; the magnetic device kit is sleeved on the magnetic device, and the inductive device is mounted on the magnetic device kit; the mounting base is fixed on the fan blade; the sliding holder is connected to the mounting base through the elastic element; The magnetic device is installed on the sliding holder, and the target element is the magnetic device; the target system is used to drive the sliding holder to reciprocate on the slide rail according to the vibration direction of the target element when vibrating, so that the magnetic device and the inductive device undergo normal relative motion.

7. The wind turbine blade according to claim 1, wherein: The damper unit further comprises a mounting base, a sliding holder, a slide rail and a magnetic device kit; the magnetic device kit is sleeved on the magnetic device, and the inductive device is mounted on the magnetic device kit; the mounting base is fixed on the fan blade; the sliding holder is connected to the mounting base through the elastic element; The magnetic device is mounted on the mounting base, and the target element is the inductive device; the target system is used to drive the sliding retainer to reciprocate on the slide rail in the vibration direction of the target element when vibrating, so that the magnetic device and the inductive device undergo normal relative motion.

8. The wind turbine blade according to any one of claims 1 to 7, wherein: The damper system is mounted on one or more of an inner surface of a fan blade skin, an outer surface of the fan blade skin, and a fan blade main beam region.

9. The wind turbine blade according to any one of claims 1 to 7, wherein: The damper system is installed on the non-vibration node of the fan blade; the distance from the damper system to the tip of the fan blade is determined according to the blade swing vibration mode; When the blade swing vibration mode is a first-order swing vibration, the distance from the damper system to the tip of the fan blade is a first distance value; When the blade swing vibration mode is a second-order swing vibration, the distance from the damper system to the tip of the fan blade is a second distance value; The first distance value is smaller than the second distance value.

10. The wind turbine blade according to any one of claims 1 to 7, wherein: An induced current is generated in the energy consumption circuit; The number of inductive devices in the energy consumption circuit satisfies a number range that enables the energy generated in the energy consumption circuit and the kinetic energy generated in the damper unit to do work together to meet a preset condition; Among them, the energy generated in the energy consumption circuit is obtained according to the work done by the induced current in the energy consumption circuit and the self-inductance magnetic energy of the coil in the energy consumption circuit; the work done by the induced current in the energy consumption circuit and the self-inductance magnetic energy of the coil in the energy consumption circuit are both related to the number of inductive devices in the energy consumption circuit.

11. The wind turbine blade according to any one of claims 1 to 7, wherein: The number of the damper units satisfies the range of the number of units that can make the work done by the damper system greater than the work done by the aerodynamic damping of the fan blades; the work done by the damper system is obtained according to the work done by each of the damper units in the damper system; The work done by the damper unit is obtained according to the mass of the damper unit and the vibration speed of the fan blade, and the aerodynamic damping work done by the fan blade is obtained according to the blade aerodynamic negative damping of the fan blade and the vibration speed of the fan blade.

12. The wind turbine blade according to any one of claims 1 to 7, wherein: When there are multiple magnetic devices in the damper unit, the multiple magnetic devices are arranged in parallel.

13. The wind turbine blade according to claim 12, wherein: The magnetic device is a bar magnet, and the magnetic poles of the bar magnet include an N pole and an S pole; the same magnetic poles of a plurality of the magnetic devices face the same direction and a preset distance is spaced between every two of the magnetic devices.

14. The wind turbine blade according to any one of claims 1 to 7, wherein: The energy dissipation device is a resistor device; the resistor device is an adjustable resistor device; the resistance value of the adjustable resistor device is adjustable, and is used to change the blade damping of the fan blade.

15. The wind turbine blade according to claim 3, wherein: When the number of the capacitive device is one, the capacitive device is connected to the energy consumption circuit of each damper unit; When there are multiple capacitive devices, one or more capacitive devices are connected to the energy consumption circuit of each damper unit.

16. The wind turbine blade according to claim 3 or 15, wherein: The inductive device and the energy consuming device in the energy consuming circuit are connected to the capacitive device in any of the following ways: The inductive device, the energy consumption device and the capacitive device are connected in series; The inductive device, the energy consumption device and the capacitive device are connected in parallel; The energy dissipation device is connected in parallel with the capacitive device, and then connected in series with the inductive device; The energy dissipation device is connected in series with the inductive device, and then connected in parallel with the capacitive device.

17. A method for producing a fan blade applied to the fan blade according to any one of claims 1 to 16, wherein: The method comprises: Obtaining the blade vibration frequency of the fan blade; According to the blade vibration frequency and frequency deviation range of the fan blade, the natural frequency of the target system is determined, and the elastic element is selected according to the natural frequency of the target system; the target system includes the elastic element and the target element; the target element is an inductive device or a magnetic device; Setting the movable direction of the target element in the damper unit and the blade swing direction of the fan blade to satisfy a preset angle range; An energy consumption circuit is provided as a loop and includes an energy consumption device and the inductive device connected to each other, and a damper unit is provided including the energy consumption circuit, the magnetic device and the elastic element; A damper system is arranged on the fan blade, and the damper system includes a damper unit arranged in the span direction of the fan blade or a plurality of damper units arranged in parallel and spaced relation, so that the target system in the damper unit resonates with the fan blade, so that relative movement occurs between the magnetic device and the inductive device in the damper unit.

18. The method according to claim 17, wherein: The step of selecting an elastic element according to the natural frequency of the target system comprises: The stiffness coefficient of the elastic element is determined according to the natural frequency of the target system, and the elastic element is selected according to the stiffness coefficient of the elastic element.

19. The method according to claim 17, wherein: The damper system also includes a capacitive device; the method also includes: Determining the resonant frequency of the energy consumption circuit according to the blade vibration frequency and the frequency deviation range of the fan blade, and selecting the inductive device and the capacitive device according to the resonant frequency of the energy consumption circuit; The energy consumption device and the inductive device in the energy consumption circuit are connected to the capacitive device.

20. The method according to claim 19, wherein: The selecting of the inductive device and the capacitive device according to the resonant frequency of the energy consumption circuit comprises: Determining the inductance value and the capacitance value according to the resonant frequency of the energy consumption circuit; The inductive device is selected according to the inductance value, and the capacitive device is selected according to the capacitance value.

21. The method according to claim 17, wherein: The damper system is arranged on the fan blade, comprising: determining a blade flutter vibration mode of the fan blade; Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode; The damper system is arranged on the fan blade according to the distance between the damper system and the tip of the fan blade and a predetermined condition; the predetermined condition is that the damper system is installed on a non-vibration node of the fan blade; Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode includes: When the blade swing vibration mode is a first-order swing vibration, determining that the distance between the damper system and the tip of the fan blade is a first distance value; When the blade swing vibration mode is a second-order swing vibration, determining that the distance between the damper system and the tip of the fan blade is a second distance value; The first distance value is smaller than the second distance value.

22. A wind turbine generator, wherein: The wind turbine comprises the wind turbine blade according to any one of claims 1 to 16.

23. A damper system, wherein: The damper system includes a damper unit arranged in a target direction of the target object or a plurality of damper units arranged in parallel and spaced apart; The damper unit includes an energy consumption circuit, a magnetic device and an elastic element; The energy consumption circuit is a loop including connected energy consumption devices and inductive devices; The movable direction of the target element in the damper unit and the vibration direction of the target object meet the preset angle range; wherein the target element is the inductive device or the magnetic device The vibration direction is perpendicular to the target direction; The elastic element and the target element are elements in a target system; the difference between the natural frequency of the target system and the vibration frequency of the target object satisfies a preset range that enables the target system and the target object to resonate, so that the target system and the target object resonate, causing relative movement between the magnetic device and the inductive device.

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