Fan blade, fan blade production method, wind driven generator and damper system

Abstract

The invention discloses a fan blade, a fan blade production method, a wind driven generator and a damper system, and the damper system is arranged on the fan blade and comprises a damper unit arranged in the spanwise direction of the fan blade or a plurality of damper units arranged in parallel at intervals. The damper unit comprises an energy consumption circuit, a magnetic device and an elastic element. And the energy consumption circuit is a loop comprising an energy consumption device and an inductive device which are connected with each other. The target element is an inductive device or a magnetic device, and the target system comprises an elastic element and the target element. When the vibration direction of the target element and the blade shimmy direction meet a preset angle range, and the difference between the inherent frequency of the target system and the blade vibration frequency of the fan blade meets a preset range, the target system and the fan blade resonate, so that the inductive device and the magnetic device move relatively, an induced current is generated in the energy consumption circuit, and the energy consumption is reduced. The induced current consumes energy through the energy consumption device and the inductive device so as to increase the damping of the blade.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on August 31, 2023, with application number 202311122642.4 and invention name “Wind Blade, Wind Blade Production Method, Wind Turbine Generator and Damper System”, the entire contents of which are incorporated by reference in 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, the blades of wind turbines will experience negative damping and self-excited vibrations, which may damage the blades and affect the safe operation of wind turbine equipment. Since the aerodynamic damping of the blades in the swinging direction is large, the negative damping phenomenon usually occurs during the swinging of wind turbine blades.

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

[0005] 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 operating safety of the wind turbine equipment.

[0006] In order to achieve the above objectives, the technical solutions provided by this application are as follows:

[0007] In a first aspect, the present application provides a fan blade, wherein a damper system is provided on the fan blade; the damper system comprises a damper unit arranged in a span direction of the fan blade or a plurality of damper units arranged in parallel and at intervals;

[0008] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0009] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0010] 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;

[0011] 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.

[0012] In a second aspect, the present application provides a method for producing a wind turbine blade applied to the wind turbine blade, the method comprising:

[0013] Obtaining the blade vibration frequency of the fan blade;

[0014] 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;

[0015] 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;

[0016] 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;

[0017] 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.

[0018] In a third aspect, the present application provides a wind turbine, wherein the wind turbine comprises the wind turbine blade provided in the first aspect of the present application.

[0019] 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;

[0020] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0021] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0022] 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;

[0023] 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.

[0024] Through the above technical solution, it can be seen that the present application has the following beneficial effects:

[0025] The present application provides a fan blade, a fan blade production method, a wind turbine generator and a damper system, wherein a damper system is provided on the fan blade, and the damper system includes a damper unit provided in the span direction of the fan blade or a plurality of damper units provided in parallel and spaced relation. The damper unit includes an energy consumption circuit, a magnetic device and an elastic element. The magnetic device can generate a magnetic field. The energy consumption circuit is a loop, and the loop includes connected energy consumption devices and inductive devices. In the damper unit, there is a target element, and according to the specific structural design of the damper unit, the target element can be an inductive device or a magnetic device, and the movable direction of the target element in the damper unit and the blade swing direction of the fan blade meet a preset angle range. In the damper unit, there is a target system, and the target system includes an elastic element and a target element. When the movable direction of the target element in the damper unit and the blade swing direction of the fan blade meet a preset angle range, if the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meets a preset range, the target system will resonate with the fan blade. During resonance, the elastic element and the target element in the target system will move. At this time, whether the target element is an inductive device or a magnetic device, relative movement will occur between the inductive device and the magnetic device. The inductive device cuts the magnetic flux in the magnetic field, causing the magnetic flux in the energy consumption circuit to change. Since the energy consumption circuit is a loop, the inductive device will further generate an induced electromotive force, and then generate an induced current in the energy consumption circuit. The energy consumption circuit includes energy consumption devices and inductive devices. The induced current will consume energy when passing through the energy consumption devices and the inductive devices, which has a vibration energy dissipation effect on the vibration of the blade as a whole in the swing direction. In this way, the blade damping can be increased to reduce 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

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying any creative work.

[0027] Figure 1 A schematic diagram of a magnet-coil system provided in an embodiment of the present application;

[0028] Figure 2 A schematic diagram of a fan blade provided in an embodiment of the present application;

[0029] Figure 3 A schematic diagram of a connection method of an inductive device, an energy dissipation device and a capacitive device provided in an embodiment of the present application;

[0030] Figure 4a to Figure 4b A schematic diagram of the structure of a damper unit provided in an embodiment of the present application;

[0031] Figure 5a to Figure 5b A schematic diagram of a three-dimensional structure of a damper unit provided in an embodiment of the present application;

[0032] Figures 6a to 7b A schematic diagram of the structure of a damper unit provided in an embodiment of the present application;

[0033] Figure 8 A flow chart of a method for producing a fan blade for a fan blade provided in an embodiment of the present application;

[0034] Fig. 9 A schematic diagram of a blade damping ratio provided in an embodiment of the present application. DETAILED DESCRIPTION

[0035] 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.

[0036] In order to facilitate the 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.

[0037] 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 coupling 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-vibrational excitation to vibrational 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.

[0038] During the operation of a wind turbine, the vibration forms of the fan blades include swing and flap. The direction of the fan blade swing is different from the direction of the fan blade flap. Swing refers to the movement of the fan blade in the chord length direction of the blade 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 fan blade in the flapping direction in the blade root coordinate system. The flapping direction is the movement direction of the pressure surface of the fan blade relative to the suction surface. In practical applications, the force area of ​​the blade in the flapping direction is large and the aerodynamic damping is large, while the force area of ​​the blade in the swing direction is small and the aerodynamic damping is small, which makes the negative damping phenomenon caused by flutter usually appear in the swing process of the fan blade.

[0039] At present, there is an urgent need to solve the negative damping problem of wind turbine blades in the swing direction.

[0040] Based on this, the embodiment of the present application provides 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, and the damper system includes a damper unit arranged in the span direction of the wind turbine blade or multiple damper units arranged in parallel and spaced apart. The damper unit includes an energy consumption circuit, a magnetic device and an elastic element. The magnetic device can generate a magnetic field. Among them, the energy consumption circuit is a loop, and the loop includes connected energy consumption devices and inductive devices. In the damper unit, there is a target element. According to the specific structural design of the damper unit, the target element can be an inductive device or a magnetic device, and the movable direction of the target element in the damper unit and the blade swing direction of the wind turbine blade meet the preset angle range. In the damper unit, there is a target system, and the target system includes an elastic element and a target element. Then, when the movable direction of the target element in the damper unit and the blade swing direction of the wind turbine blade meet the preset angle range, if the difference between the natural frequency of the target system and the blade vibration frequency of the wind turbine blade meets the preset range, the target system will resonate with the wind turbine blade. During resonance, the elastic element and the target element in the target system will move. At this time, whether the target element is an inductive device or a magnetic device, relative movement will occur between the inductive device and the magnetic device. The inductive device cuts the magnetic flux in the magnetic field, causing the magnetic flux in the energy consumption circuit to change. Since the energy consumption circuit is a loop, the inductive device will further generate an induced electromotive force, and then generate an induced current in the energy consumption circuit. The energy consumption circuit includes energy consumption devices and inductive devices. The induced current will consume energy when passing through the energy consumption devices and the inductive devices, which will dissipate the vibration energy of the blade as a whole in the swing direction. As a result, the blade damping can be increased to reduce the risk of damage to the blade due to vibration caused by negative damping, thereby improving the safety of blade operation.

[0041] 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 for the above problems below should be the contributions made by the applicant to the embodiments of the present application during the application process.

[0042] 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.

[0043] Let me explain some technical terms first.

[0044] Magnetic flux: The product of magnetic induction intensity B and the area S of a plane (effective area s, that is, the area passing perpendicular to the magnetic field lines) is called the magnetic flux passing through the plane.

[0045] Magnetic density: also known as magnetic induction intensity, it represents the number of magnetic lines of force that pass vertically through a unit area.

[0046] Residual Flux Density: The magnetic flux density remaining in the core after the excitation magnetic field is removed from the saturation state.

[0047] See also Figure 1 , Figure 1 A schematic diagram of a magnet-coil system provided in an embodiment of the present application. Figure 1 As shown, a reference coordinate system is set r -x, in this reference coordinate system, there are two directions, such as 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 RLC series circuit (see Figure 3 (a)) The inductor coil in the RLC series circuit is a loop. When the magnet moves in the x direction, the coil is fixed in position. The coil as a conductor cuts the magnetic flux lines around the magnet and moves in a cutting motion. The magnetic flux in the coil changes. Since the circuit where the coil is located is a loop, electromagnetic induction occurs, i.e., magnetoelectricity. The magnetoelectricity generates an induced electromotive force in the RLC series circuit, which in turn generates an induced current in the coil.

[0048] like Figure 1 As shown, the positions of the coils and magnets can be determined in the reference coordinate system r -x. Among them, x1 and x2 are the coordinates of the upper and lower surfaces of the coil in the thickness direction (i.e., x direction), x is any position in the vertical direction (i.e., x direction), y is the current position of the magnet in the x direction, and r1 is the radius of the coil. It can be seen that the magnetic density between the magnet and the coil can be expressed as:

[0049]

[0050] Where B is the reference coordinate system r -Magnetic density at any position in x, B r is the residual magnetic flux density. In the magnetic density formula, v is the volume of the magnet, and Respectively represent Figure 1 The two unit vectors of the magnet in the x direction and r direction, the formula x is any position in the x direction in the coordinate system, and r 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 Φn The rate of change is expressed as follows:

[0051]

[0052] 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 the following formula:

[0053]

[0054] 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 the coil. The expression for the filling factor is:

[0055]

[0056] Among them, A w is the coil sweep area. Based on this, the induced current generated in the RLC series circuit satisfies the following formula:

[0057]

[0058] 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:

[0059] Q mag =∫ v I×B

[0060] exist Figure 1 In the figure, the movement of the magnet in the x direction can be understood as vibration.

[0061] Based on the above, it can be known that if the coil is fixed in position, the magnet moves relative to the coil, and the coil is in a loop, electromagnetic induction will occur, generating an induced electromotive force and an induced current in the coil. At this time, if there is a resistor in the loop, the resistor is equivalent to an energy-consuming element. At this time, when the current flows through the resistor, it will consume energy, and when the current passes through the inductance in the coil, it will also dissipate energy. The increase in energy consumption means that the damping of the loop increases. Correspondingly, if the magnet is fixed in position, the coil moves relative to the magnet, and the coil is still in the loop, the same effect will occur.

[0062] Based on the above content, if the circuit is installed in the fan blade, the vibration energy of the fan blade will be dissipated through the circuit, the damping of the circuit will be improved, and accordingly, the effect of increasing the damping of the fan blade will be achieved. The above content is the relevant principle of increasing the damping of the fan blade. Based on this principle, the specific structure of the damper system installed on the fan blade can be designed as follows.

[0063] 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:

[0064]

[0065] Where m is the mass of the magnet, r s is the structural damping coefficient of the magnet-spring system, and k is the spring stiffness or the stiffness coefficient of the elastic element of the spring. The vibration distance of the fan blade is z , its vibration amplitude is Λ (the vibration amplitude can be understood as the maximum value of the vibration distance), and the blade vibration frequency is Ω, then z=Λcos(Ωt).

[0066] 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.

[0067] 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:

[0068]

[0069] 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 has a speed relative to the coil. It can be seen that a larger response amplitude can change the magnetic flux to the greatest extent, and at this time, an induced electromotive force will be caused due to the electromagnetic induction phenomenon, so that an induced current will be generated in the coil. Among them, the natural frequency of the magnet-spring system can be adjusted by the stiffness coefficient of the elastic element of the spring.

[0070] In order to make the induced current larger, further, when the coil loop also includes a capacitor, such as Figure 3 (a) shows the RLC series circuit. The resonant frequency ω of the current in the coil of the RLC series circuit is I It can be expressed as:

[0071]

[0072] 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≈ω s ≈ω I When the induction current in the coil increases, the energy consumption on the resistor and the energy consumption on the coil inductance will increase further, 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.

[0073] Based on the above content, the embodiment of the present application provides a fan blade, in which a damper system is provided. It should be understood that the various specific structures of the damper system in the embodiment of the present application are realized by using the above design principle, and can be used to increase the damping of the fan blade, as follows.

[0074] See also Figure 2 , Figure 2 A schematic diagram of a fan blade provided in an embodiment of the present application. Figure 2 As shown, the blade root coordinate system of the blade is a YZ coordinate system, the Y direction in the YZ coordinate system represents the blade swing direction, the Z direction represents the blade span direction, the blade span direction and the blade swing direction are perpendicular to each other, that is, the Y direction and the Z direction are perpendicular to each other.

[0075] The following first introduces the installation position of the damper system in the fan blade.

[0076] like Figure 2 As shown, for example, the damper system 22 includes a damper unit 11 or a plurality of damper units 11 arranged in parallel and spaced relation in the span direction (Z direction) of the fan blade. The term "arranged in parallel and spaced relation" means that the plurality of damper units may not contact each other, and the damper units are arranged in parallel and spaced relation with each other, and the spaced relation 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 c The damper units are distributed along the blade span direction (Z direction). It can be understood that each damper unit can improve 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 damping added to the fan blade.

[0077] As an optional example, the damper system is mounted on one or more of the inner surface of the fan blade skin, the outer surface of the fan blade skin, and the main beam region of the fan blade.

[0078] Among them, the main beam refers to the main load-bearing structure in the blade, which is made of fiber and matrix infusion to provide 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. It plays a role in shear resistance and is divided into single web and double web structures, which are 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 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. The vicinity is not limited here and can be determined according to actual conditions.

[0079] In addition, the installation position of the damper system in the blade can also be determined according to actual conditions, which is not a limitation here. It only needs to ensure that when the damper system includes multiple damper units, the multiple damper units are arranged in the span direction (Z direction) of the fan blade. In actual applications, the damper system can be installed in the fan blade by bolting or gluing.

[0080] like Figure 2 As shown, 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 as d1. The distance between the installation 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 as d2. The length of the blade is represented as L blade .

[0081] 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 and second-order swing. Among them, the vibration mode refers to the form of vibration of the system and has nothing to do with the size of the vibration displacement. During the swing of the fan blades, there will be vibration nodes on the fan blades. The vibration node is also called the mechanical vibration vibration mode node, which refers to the intersection node of the vibration mode and the original shape of the structure at a certain order of natural frequency. The swing amplitude at the vibration mode node is zero. The first-order swing refers to the swing with 0 vibration nodes, and the second-order swing refers to the swing with 1 vibration node.

[0082] It can be understood that at the vibration 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 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 node of the fan blade. A non-vibration node is a position in the fan blade that is not a vibration node.

[0083] On the basis that the damper system is installed at the non-vibrational node of the fan blade, the distance from the damper system to the tip of the fan blade is determined according to the vibrational mode of the blade. Among them, the distance from the damper system to the tip of the fan blade is the distance from the installation start end of the damper system to the tip of the fan blade, that is, d1.

[0084] Specifically, 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.

[0085] It should be understood that the embodiments of the present application do not limit the specific values ​​of the first distance value and the second distance value, which can be determined according to actual conditions. For example, when the vibration mode is a first-order shimmy, the first distance value is 1 / 3 of the fan blade; when the vibration mode is a second-order shimmy, the second distance value is 1 / 2 of the fan blade. Among them, the setting result of "the first distance value during the first-order shimmy is less than the second distance value during the second-order shimmy" can be determined according to actual tests. According to actual conditions, when a second-order shimmy occurs, in order to make the damper system have a better effect on improving the damping of the fan blades, the second distance value is made greater than the first distance value.

[0086] 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 tests and can enable the damper system at this installation position to have a better effect of increasing damping for the fan blades.

[0087] 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.

[0088] The internal structure of the damper unit in the damper system will be introduced in detail below.

[0089] As an optional example, the damper unit 11 includes an energy consumption circuit, a magnetic device and an elastic element.

[0090] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices. For example, the loop can be a closed loop. In the damper unit, there are a target element and a target system. The target system includes an elastic element and a target element. According to the installation position of each structure in the damper unit, the target element can be an inductive device or a magnetic device. The direction of the target element when vibrating and the blade swing direction of the fan blade meet the preset angle range, and the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meets the preset range that can make the target system resonate with the fan blade.

[0091] Among them, magnetic devices are also called magnetic materials. Magnetic materials mainly refer to materials that can directly or indirectly generate magnetism from transition elements such as iron, cobalt, nickel and their alloys. Magnetic materials can generate magnetic fields. For example, the elastic element is a spring or other element with an elastic element stiffness coefficient, and the type of spring is not limited here. For example, the energy-consuming device can be a resistor device or other energy-consuming device. For example, the inductive device can be a conductive metal material such as a coil, a copper tube, an aluminum tube, and an iron tube.

[0092] 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 2R, after the current changes, the energy consumption of the energy-consuming device can be changed, thereby changing the blade damping of the fan blade. For example, the inductive device, capacitive device (see below for details), elastic element, etc. in the embodiment of the present application can also adopt an inductive device with adjustable inductance value, a capacitive device with adjustable capacitance value, an elastic element with adjustable elastic element stiffness coefficient, etc., so as to facilitate the adjustment of parameters such as inductance value, capacitance value, and elastic element stiffness coefficient.

[0093] It can be seen that when the resistor device is a resistor device with non-adjustable resistance, a resistor device with a suitable resistance value can be directly selected to meet the demand for energy consumption. Similarly, an inductive device with a suitable inductance value, a capacitive device with a suitable capacitance value (see below for details), and an elastic element with a suitable elastic element stiffness system can also be directly selected.

[0094] The number of magnetic devices in the damper unit may be one or more, and the number of inductive devices may be one or more. When the number of magnetic devices in the damper unit is multiple, the multiple magnetic devices may be arranged in parallel. When the number of inductive devices is multiple, the multiple inductive devices may also be arranged in parallel.

[0095] The central axis positions of the inductive device and the magnetic device are the same or close, so that when the inductive device and the magnetic device move relative to each other, the inductive device cuts the magnetic flux lines 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 lines 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 Figure 1 The x direction is shown, and the central axis coincides.

[0096] In practical applications, the inductive device may move relative to the magnetic device, that is, the inductive device moves / vibrates; the magnetic device may move relative to the inductive device, that is, the magnetic device moves / vibrates. Therefore, the target element is a structure in the damper system that resonates with the fan blade together with the elastic element, and the target element may be an inductive device or a magnetic device. The target element is an element in the target system, and the target system also includes an elastic element. When the target element vibrates, the elastic element in the target system also vibrates in the same direction at the same time, which can be understood as the target element vibrates in the same direction as the elastic element, that is, the direction of the target system vibration. That is, it can also be further understood that the target system is a structure in the damper system that resonates with the fan blade.

[0097] 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 the 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.

[0098] 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 the preset range that can make the target system resonate with the fan blade. Among them, "adjustment" can be understood as when the elastic element is an elastic element with an adjustable elastic element stiffness coefficient, the elastic element stiffness coefficient of the elastic element can be directly adjusted; "adjustment" can also be understood as when the elastic element is an elastic element with an unadjustable elastic element stiffness coefficient, the elastic element in the damper system can be adjusted, that is, directly selecting an elastic element, the elastic element stiffness coefficient of the selected elastic element can make the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meet the preset range that can make the target system resonate with the fan blade.

[0099] 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 the target system to resonate with the fan blades are met. At this time, the target system resonates with the fan blades, the target system resonates with the foundation excitation, and the target system has a large response amplitude / vibration amplitude. The target element in the target system has a large response amplitude. Whether the target element is an inductive device or a magnetic device, relative movement will occur between the inductive device and the magnetic device. The inductive device cuts the magnetic flux in the magnetic field, thereby changing the magnetic flux in the energy consumption circuit. Since the energy consumption circuit is a loop, the inductive device will generate an induced electromotive force, and then generate an induced current in the energy consumption circuit. There are energy consumption devices and inductive devices in the energy consumption circuit, and the induced current generates energy consumption through the energy consumption devices and the inductive devices. That is, the vibration energy of the fan blade can be dissipated through the energy consumption devices and the inductive devices in the damper unit, so as to achieve the effect of improving the blade damping. In practical applications, according to experiments, it can be known that the increase in the damping of the energy consumption circuit in each damper unit installed in the fan blade is equivalent to increasing the damping of the fan blade. In addition, when the damping of the fan blade increases, the damping ratio of the fan blade also increases accordingly. Damping is the various frictions and other obstacles that attenuate free vibration. The damping ratio refers to the ratio of the damping coefficient to the critical damping coefficient, which expresses the standardized damping size of the structure.

[0100] 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.

[0101] Based on the above content, it can be known that by setting the damper system in the fan blade, the negative damping problem of the fan blade in the swing direction can be effectively solved, and the operating safety of the wind turbine equipment can be improved. In addition, since the fatigue load of the fan blade is related to the alternating load amplitude, increasing the damping of the fan blade can also reduce the alternating load amplitude, which will have the effect of reducing the fatigue load of the fan blade, so as to further improve the safety and reliability of the unit. Moreover, after reducing the fatigue load of the fan blade, it is also possible to save the materials that are used to solve the negative damping problem of the blade, reduce material costs, and save blade design and manufacturing costs.

[0102] It can be understood that the direction of the target element in the damper unit when vibrating and the blade swing direction of the fan blade meet the preset angle range, and the difference between the natural frequency of the target system and the blade vibration frequency of the fan blade meets the preset range, which is two conditions for the resonance between the target system and the fan blade. Then, the direction of the target element in each damper unit when vibrating and the natural frequency of the target system both meet these two conditions, and it is not limited that the direction of the target element in each damper unit when vibrating and the natural frequency of the target system are the same.

[0103] It can also be understood that in practice, the natural frequency of an object itself is about thousands of hertz, and the vibration frequency of a fan blade is a few tenths of hertz. In order to make the target system resonate with the fan blade, in addition to the target element, the target system also needs an elastic element to adjust the natural frequency of the target system, so that the difference between the natural frequency of the target system and the vibration frequency of the fan blade meets the preset range.

[0104] 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 blade vibration frequency of the fan blade, 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 larger, and the effect of improving the damping of the fan blades is better.

[0105] It can be seen that the energy consumption circuit can only resonate if both inductive devices 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, which can 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 can meet the preset range that enables the target system to resonate with the wind turbine blade, that is, Ω≈ω s ≈ω I .

[0106] 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. Among them, ω 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 .

[0107] There is a connection path between the energy-consuming devices and the inductive devices in the energy-consuming circuit and the capacitive devices in the damper system, that is, the energy-consuming circuit includes not only energy-consuming devices and the inductive devices but also capacitive devices.

[0108] As an optional example, the number of the capacitive device is one. In this case, the energy consumption circuit of each damper unit is connected to the capacitive device. That is, the entire damper system is connected to one capacitive device as a whole.

[0109] As another optional example, the number of capacitive devices is multiple. In this case, one or more capacitive devices can be connected to the energy consumption circuit of each damper unit. Among them, the capacitive devices connected to the energy consumption circuit of some or all 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 three capacitive devices can also be connected to the energy consumption circuit of each damper unit, 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.

[0110] As an optional example, the capacitive device may be a capacitive device with an adjustable capacitance value. As another optional example, the capacitive device is a capacitive device with an unadjustable capacitance value, such as a capacitor composed of dual capacitor plates.

[0111] For example, the inductance of the inductive device and the capacitance 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 a preset range that enables the target system to resonate with the wind turbine blade.

[0112] 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, the inductance value of the inductive device and the capacitance value of the capacitive device can be directly adjusted; "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, an inductive device and a capacitive device are directly selected, and 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.

[0113] See also Figure 3 , Figure 3 A schematic diagram of a connection method of an inductive device, an energy dissipation device and a capacitive device provided in an embodiment of the present application. Figure 3 As shown in (a)-3(d), the connection method between the inductive device and the energy dissipation device and the capacitive device in the energy dissipation circuit is any of the following:

[0114] The inductive device, the energy dissipative device and the capacitive device are connected in series;

[0115] The inductive device, the energy dissipative device and the capacitive device are connected in parallel;

[0116] The energy dissipation device is connected in parallel with the capacitive device and then connected in series with the inductive device;

[0117] The energy dissipation device is connected in series with the inductive device and then connected in parallel with the capacitive device.

[0118] like Figure 3 As shown in (a), the first connection mode is that the inductive device, the energy consumption device and the capacitive device are connected in series, and when the energy consumption circuit resonates, it is a series resonance. Figure 3 As shown in (b), the second connection mode is that the inductive device, the energy consumption device and the capacitive device are connected in parallel. When the energy consumption circuit resonates, it is parallel resonance. It can be seen that the resonant frequency formulas in series resonance and parallel resonance are both

[0119] like Figure 3 As shown in (c), the third connection method is to connect the energy consumption device in series with the inductive device and then connect it in parallel with the capacitive device. The resonant frequency formula of the energy consumption circuit in this connection method is:

[0120]

[0121] like Figure 3 As shown in (d), the fourth connection mode is that the energy consumption device is connected in parallel with the capacitive device, and then connected in series with the inductive device. The resonant frequency formula of the energy consumption circuit of this connection mode is:

[0122]

[0123] It is understandable that when the connection method of the inductive device, the energy dissipation device and the capacitive device in the energy dissipation circuit is the third connection method and the fourth connection method, 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.

[0124] It can also be understood that if the inductive device is a coil, when the energy consumption circuit includes multiple coils, the inductance value L in the above resonant frequency formula is the inductance value obtained by taking the multiple coils as a whole. If the energy consumption device is a resistor, when the energy consumption circuit includes multiple resistors, the resistance value R in the above resonant frequency formula is the resistance value obtained by taking the multiple resistors as a whole. If the capacitive device is a capacitor, when the energy consumption circuit includes multiple capacitors, the capacitance value C in the above resonant frequency formula is the capacitance value obtained by taking the multiple capacitors as a whole.

[0125] From the above, we can see that through Ω≈ω s ≈ω IThe 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.

[0126] Based on the above content, the structures of six damper units will be introduced in detail below. The damper unit in the damper system can be of any structure, or the damper system includes damper units of multiple different structures. Figure 4a and Figure 4b , Figure 4a and Figure 4b A schematic structural diagram of a group of damper units provided in an embodiment of the present application.

[0127] like Figure 4a and Figure 4b As shown, the damper unit includes, in addition to the energy dissipation device 2 , the inductive device 6 , the magnetic device 3 , and the elastic element 5 , a mounting base 1 , a sliding retainer 4 , and a sliding rail 8 . Figure 4a and Figure 4b Also shown is a capacitor device 7 which may be included in the damper unit. Figure 4a and Figure 4b In the figure, energy-consuming devices are represented by adjustable resistors, inductive devices are represented by coils (multiple coils can form a coil group), magnetic devices are represented by magnets (multiple magnets can form a magnet group), elastic elements are represented by springs, and capacitive devices are 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, Figure 4a and Figure 4b The total weight of the magnetic device and the sliding cage can be expressed as m, the stiffness of the spring is k, ω s is the natural frequency of the target system, and the number of magnetic devices is N m After testing, N m ≥2.

[0128] like Figure 4a and Figure 4b As shown, for example, the magnets in the magnet group are bar magnets, and the magnetic poles of the bar magnets include N poles and S poles. The same magnetic poles of each magnetic device and the adjacent magnetic device are oriented in the same direction, that is, the arrangement of each magnetic device and the adjacent magnetic device is the same. It should be understood that the magnets can also be other magnets besides bar magnets, which is not limited here, as long as they can generate a magnetic field.

[0129] The mounting base 1 is used to be fixed on the fan blade so that the entire damper system is fixed on the fan blade. The sliding retainer 4 is connected to the mounting base 1 through the elastic element 5, and the sliding retainer 4 can slide on the slide rail 8. As an optional example, when the elastic element is a spring, the spring can be sleeved on the slide rail, such as Figure 4a and 4b As shown. Among them, the sliding retainer 4 can slide on the slide rail 8 because the target system including the elastic element 5 and the target element resonates with the fan blade, and the elastic element 5 and the target element are driven by the vibration. The vibration direction of the target system is the vibration direction of the target element. It can be seen that the direction of the target element when vibrating and the blade swing direction of the fan blade (that is, the Y direction) meet the preset angle range, that is, the vibration direction of the target element is determined. In practice, the positions of various structures in the damper unit (such as the mounting base, the slide rail, the elastic element, the sliding retainer, the magnetic device, and the inductive device) will be adjusted so that the vibration direction of the target element and the blade swing direction meet the preset angle range.

[0130] like Figure 4a and Figure 4b As shown, the inductive devices 6 are all mounted on the mounting base 1, the position of the inductive devices 6 is fixed, and the magnetic devices 3 are all mounted on the sliding holder 4. At this time, 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 according to the vibration direction of the target element when vibrating, and the magnetic device 3 on the sliding holder 4 and the inductive device 6 on the mounting base 1 have normal relative motion or tangential relative motion. Therefore, when the normal relative motion occurs, the inductive device 6 cuts the magnetic flux lines longitudinally; when the tangential relative motion occurs, the inductive device cuts the magnetic flux lines transversely. Whether it is the normal relative motion or the tangential relative motion, the magnetic flux passing through the inductive device will change, so that an induced current is generated in the energy consumption circuit.

[0131] The direction of relative movement between the magnetic device 3 and the inductive device 6 is determined by the connection mode between the slide rail and the mounting base and the slide holder. Figure 4a A connection method between the slide rail and the mounting base and the slide holder is provided, so that when the target system vibrates, normal relative motion occurs between the magnetic device 3 and the inductive device 6 . Figure 4b Another connection mode between the slide rail and the mounting base and the slide holder is provided, so that when the target system vibrates, a lateral relative movement occurs between the magnetic device 3 and the inductive device 6 .

[0132] In the embodiment of the present application, the normal direction may 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, and the interval angle may be an error angle within the allowable range, and the error angle is usually small, which is not limited here, and may be determined according to actual conditions. The tangential direction may 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, and the interval angle may be an error angle within the allowable range, and the error angle is usually small, which is not limited here, and may 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 refers to 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 retaining frame 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.

[0133] Specifically, Figure 4a In the specific structure shown, 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 on the fan blades by installing bolts in the bolt holes. When the bolt holes are not provided on the mounting base, the mounting base can be pasted on the fan blades. The sliding retainer 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 in parallel on the two long frames of the mounting base, and the magnetic devices are installed in parallel on the sliding retainer. For example, the number of inductive devices installed in parallel 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 in parallel on the sliding retainer. 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.

[0134] The slide rail includes a first slide rail ( Figure 4a The left rail) and the second rail ( Figure 4a The slide rail is fixed in position. The elastic element includes a first elastic element ( Figure 4a The elastic element on the upper left of the middle), the second elastic element ( Figure 4a The elastic element in the upper right middle), the third elastic element ( Figure 4a The lower left elastic element) and the fourth elastic element ( Figure 4aThe two ends of the first slide rail are respectively connected (fixed to) the two long frames of the mounting base and pass through the sliding holder. The two ends of the second slide rail are also respectively connected (fixed to) the two long frames of the mounting base and pass through the sliding holder. The sliding holder is connected to one long frame of the mounting base through the first elastic element and the second elastic element, and the sliding holder 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 holder.

[0135] 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 between the magnetic device and the inductive device can occur. 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 Figure 4a The central axis direction of the magnetic device in the embodiment may be the Y direction. That is, the central axis direction of each elastic element, the central axis direction of each inductive device, and the central axis direction of each magnetic device are all in the Y direction. In practical applications, the damper unit can be installed on the fan blade according to the constraint in this direction.

[0136] Based on this, Figure 4a The direction in which the inductive devices or magnetic devices are arranged in parallel 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 magnetic devices are both the Y direction).

[0137] When the target system resonates with the fan blades, the 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 on the sliding holder and the inductive device move relative to each other in the normal direction. As a result, an induced current will be generated in the energy consumption circuit. In practical applications, such as Figure 4a As shown, when the first elastic element and the second elastic element are compressed, the third elastic element and the fourth elastic element are stretched.

[0138] It is understandable that in Figure 4a In the structure shown, the normal direction of the inductive device is the Y direction, and the tangent 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 Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 4aAs shown, 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 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.

[0139] See also Figure 4b The specific structure shown, Figure 4b The installation position relationship of the mounting base, sliding retainer, inductive device, and magnetic device in Figure 4a Same, but the installation position relationship between the slide rail and the elastic element is the same as Figure 4a Specifically, the elastic element includes a first elastic element ( Figure 4b The elastic element on the left side of the middle) and the second elastic element ( Figure 4b The position of the slide rail is fixed, and the two ends of the slide rail are connected to the two short frames of the mounting base. There is a through hole 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 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 another short 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.

[0140] Based on the above structure, the central axis of each inductive device is in the same direction as the central axis of each magnetic device. The central axis of each elastic element and the central axis of the slide rail are in the same direction. Moreover, the central axis direction of the magnetic device and the central axis direction of the elastic element are perpendicular to each other. In this way, the magnetic device can move in the tangential direction of the central axis direction of the magnetic device during movement, and tangential relative movement between the magnetic device and the inductive device can occur. 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 tangential direction of the central axis direction of the magnetic device needs to meet the preset angle range with the swing direction of the blade, for example Figure 4a The central axis direction of the magnetic device in the embodiment may be the Z direction. That is, the central axis direction of each inductive device and each magnetic device is in the Z direction. The central axis direction of each elastic element and the central axis direction of the slide rail is in the Y direction. In practical applications, the damper unit can be installed on the fan blade according to the constraints in this direction.

[0141] Based on this, Figure 4bThe direction in which the inductive device or magnetic device is arranged in parallel 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 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, each elastic element and magnetic device vibrates, 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 practical applications, such as Figure 4b As shown, when the first elastic element is compressed, the second elastic element is stretched.

[0142] exist Figure 4b In the structure shown, the normal direction of the inductive device is the Z direction, and the tangent 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 central axis of the coil (such as Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 4b As shown, 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. When the magnet group vibrates in the Y direction, the coil cuts the magnetic flux of the magnetic device in the Y direction (the tangential direction of the coil). That is, the magnet group moves relative to the tangential direction of the coil group along the Y direction through the spring, causing the magnetic flux to change and generate an induced current.

[0143] See again Figure 4b Since there is 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 arranged in the middle of the coil to increase the magnetic flux.

[0144] See also Figure 5a and Figure 5b , Figure 5a to Figure 5b A three-dimensional structural diagram of a damper unit provided in an embodiment of the present application is specifically as follows Figure 4b 3D schematic of the structure shown.

[0145] like Figure 5a and 5b As shown in the figure, the damper unit includes a mounting base 1, a magnet 3, a spring 5, a coil 6, a slide rail 8, a magnet fixing frame 110, a spring fixing frame 111, a slider 112 and a coil fixing frame 113. The variable resistor in the same energy consumption circuit as the coil is not shown in the figure, and the capacitor is not shown in the figure. In the actual structure, the magnet fixing frame 110 and the slider 112 are equivalent to Figure 4b The sliding retainer 4 in the.

[0146] 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 w , multiple coils 6 form a coil group. In order to increase the damping effect of the magnet within a stroke, a multi-coil method can be used to increase the energy dissipation of the induced current. At this time, the position of the coil group is fixed, and the magnet 3 causes a change in magnetic flux through the tangential relative movement of the spring 5 and the coil group to generate an induced current.

[0147] Understandably, Figure 5a and Figure 5b This is only an illustrative three-dimensional structural diagram and is not limited here.

[0148] See also Figure 6a and Figure 6b , Figure 6a and Figure 6b A schematic structural diagram of another group of damper units provided in an embodiment of the present application.

[0149] like Figure 6a and Figure 6b As shown, the damper unit includes, in addition to the energy dissipation device 2 , the inductive device 6 , the magnetic device 3 , and the elastic element 5 , a mounting base 1 , a sliding retainer 4 , and a sliding rail 8 . Figure 6a and Figure 6b Also shown is a capacitor device 7 which may be included in the damper unit. Figure 6a and Figure 6b In the figure, energy-consuming devices are all represented by adjustable resistors, inductive devices are all represented by coils (multiple coils can form a coil group), magnetic devices are all represented by magnets (multiple magnets can form a magnet group), elastic elements are all represented by springs, and capacitive devices are all represented by adjustable capacitors. This is only for example and does not constitute a limitation.

[0150] like Figure 6a and Figure 6b As shown, for example, the magnets in the magnet group are bar magnets, and the magnetic poles of the bar magnets include N poles and S poles. The same magnetic poles of each magnetic device and the adjacent magnetic device are oriented in the same direction, that is, the arrangement of each magnetic device and the adjacent magnetic device is the same. It should be understood that the magnets can also be other magnets besides bar magnets, which is not limited here, as long as they can generate a magnetic field.

[0151] The mounting base 1 is used to be fixed on the fan blade so that the entire damper system is fixed on the fan blade. The sliding retainer 4 is connected to the mounting base 1 through the elastic element 5, and the sliding retainer 4 can slide on the slide rail 8. As an optional example, when the elastic element is a spring, the spring can be sleeved on the slide rail, such as Figure 6a and 6b As shown. Among them, the sliding retainer 4 can slide on the slide rail 8 because the target system including the elastic element 5 and the target element resonates with the fan blade, and the elastic element 5 and the target element are driven by the vibration. The vibration direction of the target system is the vibration direction of the target element. It can be seen that the direction of the target element when vibrating and the blade swing direction of the fan blade (that is, the Y direction) meet the preset angle range, that is, the vibration direction of the target element is determined. In practice, the positions of various structures in the damper unit (such as the mounting base, the slide rail, the elastic element, the sliding retainer, the magnetic device, and the inductive device) will be adjusted so that the vibration direction of the target element and the blade swing direction meet the preset angle range.

[0152] like Figure 6a and Figure 6b As shown, the magnetic devices 3 are all mounted on the mounting base 1, the inductive devices 6 are fixed in position, and the inductive devices 6 are all mounted on the sliding holder 4. At this time, 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 according to the vibration direction of the target element when vibrating, and the inductive device 6 on the sliding holder 4 and the magnetic device 3 on the mounting base 1 have normal relative motion or tangential relative motion. Therefore, when the normal relative motion occurs, the inductive device 6 cuts the magnetic flux lines longitudinally; when the tangential relative motion occurs, the inductive device cuts the magnetic flux lines transversely. Whether it is the normal relative motion or the tangential relative motion, the magnetic flux passing through the inductive device will change, so that an induced current is generated in the energy consumption circuit.

[0153] The direction of relative movement between the magnetic device 3 and the inductive device 6 is determined by the connection mode between the slide rail and the mounting base and the slide holder. Figure 6a A connection method between the slide rail and the mounting base and the slide holder is provided, so that when the target system vibrates, normal relative movement occurs between the inductive device 6 and the magnetic device 3. Figure 6b Another connection mode between the slide rail and the mounting base and the slide holder is provided, so that when the target system vibrates, a lateral relative movement occurs between the inductive device 6 and the magnetic device 3 .

[0154] Specifically, Figure 6a In the specific structure shown, the sliding retainer is a four-frame structure, including two long frames and two short frames. The mounting base is located between the two long frames of the sliding retainer and is parallel to the two long frames of the sliding retainer. Bolt holes are provided on the mounting base to fix the mounting base on the fan blade by installing bolts in the bolt holes. When the mounting base is not provided with bolt holes, the mounting base can be pasted on the fan blade.

[0155] The inductive devices can be installed in parallel on the two long frames of the sliding holder, and the magnetic devices can be installed in parallel on the sliding holder. For example, the number of inductive devices installed in parallel on the two long frames of the sliding holder is the same, and the number of inductive devices installed on one long frame is the same as the number of magnetic devices installed in parallel on the mounting base. 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.

[0156] The slide rail includes a first slide rail ( Figure 6a The left rail) and the second rail ( Figure 6a The slide rail is fixed in position. The elastic element includes a first elastic element ( Figure 6a The elastic element on the upper left of the middle), the second elastic element ( Figure 6a The elastic element in the upper right of the middle), the third elastic element ( Figure 6a The lower left elastic element) and the fourth elastic element ( Figure 6a The two ends of the first slide rail respectively penetrate the two long frames of the sliding holder, and the middle of the slide rail is fixed to the mounting base. The two ends of the second slide rail also penetrate the two long frames of the sliding holder, and the middle of the slide rail is fixed to 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.

[0157] 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 inductive device can move in the direction of the central axis when in motion, and normal relative motion between the inductive device and the magnetic device can occur. At this time, in order to make the vibration direction of the inductive device and the swing direction of the blade meet the preset angle range, the central axis direction of the inductive device needs to meet the preset angle range with the swing direction of the blade, for example Figure 6a The central axis direction of the inductive device in the embodiment may be the Y direction. That is, the central axis direction of each elastic element, each inductive device, and each magnetic device are all in the Y direction. In practical applications, the damper unit can be installed on the fan blade according to the constraint in this direction.

[0158] Based on this, Figure 6aThe direction in which the inductive devices or magnetic devices are arranged in parallel 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 magnetic devices are both the Y direction).

[0159] When the target system resonates with the fan blades, the 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 inductive device on the sliding holder and the magnetic device move relative to each other in the normal direction. As a result, an induced current will be generated in the energy consumption circuit. In practical applications, such as Figure 6a As shown, when the first elastic element and the second elastic element are compressed, the third elastic element and the fourth elastic element are stretched.

[0160] It is understandable that in Figure 6a In the structure shown, the normal direction of the inductive device is the Y direction, and the tangent 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 Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 6a As shown, 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 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 the magnetic flux to change to generate an induced current.

[0161] See also Figure 6b The specific structure shown, Figure 6b The installation position relationship of the mounting base, sliding retainer, inductive device, and magnetic device in Figure 6a Same, but the installation position relationship between the slide rail and the elastic element is the same as Figure 6a Specifically, the elastic element includes a first elastic element ( Figure 6b The elastic element on the left side of the middle) and the second elastic element ( Figure 6b The slide rail includes a first slide rail ( Figure 6b The left rail) and the second rail ( Figure 6b The slide rail on the right side is 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 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.

[0162] Based on the above structure, the central axis of each inductive device is in the same direction as the central axis of each magnetic device. The central axis of each elastic element and the central axis of the slide rail are in the same direction. Moreover, the central axis direction of the inductive device and the central axis direction of the elastic element are perpendicular to each other. In this way, the inductive device can move in the tangential direction of the central axis direction of the inductive device during movement, and tangential relative movement between the inductive device and the magnetic device can occur. At this time, in order to make the vibration direction of the inductive device and the swing direction of the blade meet the preset angle range, the tangential direction of the central axis direction of the inductive device needs to meet the preset angle range with the swing direction of the blade, for example Figure 6a The central axis direction of the inductive device in the embodiment may be the Z direction. That is, the central axis direction of each inductive device and each magnetic device is in the Z direction. The central axis direction of each elastic element and the central axis direction of the slide rail is in the Y direction. In practical applications, the damper unit can be installed on the fan blade according to the constraints in this direction.

[0163] Based on this, Figure 6b The direction in which the inductive device or magnetic device is arranged in parallel 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 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, each elastic element and the 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 practical applications, such as Figure 4b As shown, when the first elastic element is compressed, the second elastic element is stretched.

[0164] exist Figure 6b In the structure shown, the normal direction of the inductive device is the Z direction, and the tangent 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 central axis of the coil (such as Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 6b As shown, the vibration direction / movement direction of the coil group can be the Y direction, and the tangential direction of the coil is the Y direction. When the coil group vibrates in the Y direction, the coil cuts the magnetic flux of the magnetic device in the Y direction (the tangential direction of the coil). That is, the relative movement of the coil group along the Y direction and the tangential direction of the magnet group causes the magnetic flux to change and generate an induced current. See again Figure 6b Since there is 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 arranged in the middle of the coil to increase the magnetic flux.

[0165] In various structures of the damper unit, the same magnetic poles of multiple magnetic devices face the same direction and a preset distance is set between every two magnetic devices. It is understandable that when the same magnetic poles of multiple magnetic devices face the same direction, the spacing between the magnetic devices and adjacent magnetic devices can be appropriately adjusted to avoid repulsion of like magnetic poles. It can be seen that when the number of magnetic devices remains unchanged, the larger the spacing, the larger the space occupied by the damper unit, and the spacing can be determined according to actual needs.

[0166] See also Figure 7a-Figure 7b , Figure 7a-Figure 7b A schematic structural diagram of another group of damper units provided in an embodiment of the present application.

[0167] like Figure 7a and Figure 7b As shown, 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 sleeved 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 on the fan blade; the sliding retainer 4 is connected to the mounting base 1 through the elastic element 5. For example, when the inductive device 6 is a coil, the coil can be wound on the magnetic device kit 9. The magnet group jacket 9 is a magnetic conductive material, such as copper, and the magnet group jacket 9 is a thin cylindrical structure with a hollow interior.

[0168] It can be seen that since the magnetic device set 9 is mounted on the magnetic device 3 and the inductive device 6 is mounted on the magnetic device set 9, the inductive device and the magnetic device can only move relative to each other in the normal direction. The magnetic device can be mounted on a sliding holder or on a mounting base. When the magnetic device is mounted on a sliding holder, the target element is the magnetic device, and the position of the inductive device and the magnet set outer shell is fixed, such as Figure 7a As shown. Figure 7a In the structure shown, for example, the magnet assembly housing 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 position of the magnetic device is fixed, such as Figure 7b As shown. Figure 7b In the structure shown, for example, the magnet group jacket can be connected to the sliding holder. 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 move relative to each other in the normal direction, and the magnetic device penetrates and longitudinally cuts the magnetic flux lines. It can be seen that when the target element is an inductive device, the inductive device and the magnet group jacket move together.

[0169] like Figure 7aIn the specific structure shown, the mounting base is a four-frame structure, including two long frames and two short frames. Bolt holes are provided on the long frames, so that the mounting base can be fixed to the fan blades by installing bolts in the bolt holes. When the mounting base is not provided with bolt holes, the mounting base can be pasted on the fan blades. The sliding retainer 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 devices are installed in parallel on the sliding retainer. The magnet group outer sleeve is arranged on the outside of the sliding retainer. Figure 7a As shown, the energy consumption circuit includes an inductive device, a variable capacitor and a variable resistor connected in series.

[0170] Specifically, the elastic element includes a first elastic element ( Figure 7a The elastic element on the left side of the middle) and the second elastic element ( Figure 7a The position of the slide rail is fixed, and the two ends of the slide rail are connected to the two short frames of the mounting base. There is a through hole 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 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 another short 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.

[0171] Based on the above structure, the central axis of the inductive device, the central axis of each magnetic device, the central axis of each elastic element, 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 of the magnetic device when in motion, and normal relative motion between the magnetic device and the inductive device can occur. 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 Figure 7a The central axis direction of the magnetic device in the embodiment may be the Y direction. In practical applications, the damper unit may be mounted on the fan blade according to the constraints in this direction.

[0172] Based on this, Figure 7a The direction in which the magnetic devices are arranged in parallel 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 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 normal direction. As a result, an induced current will be generated in the energy consumption circuit later. In practical applications, such as Figure 7a As shown, when the first elastic element is compressed, the second elastic element is stretched.

[0173] exist Figure 7a In the structure shown, the normal direction of the inductive device is the Y direction, and the tangent 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 Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 7a As shown, the vibration direction / movement direction of the magnet group can be the Y direction, and the tangent direction of the coil is the Z direction. When the magnet group vibrates in the Y direction, the coil cuts the magnetic flux of the magnetic device in the Y direction (the normal direction of the coil). That is, the magnet group moves relatively inside the coil along the Y direction through the spring to cause the magnetic flux change to generate an induced current.

[0174] like Figure 7b In the specific structure shown, the sliding retainer is a four-frame structure, including two long frames and two short frames. The mounting base is located between the two long frames of the sliding retainer and is parallel to the two long frames of the sliding retainer. Bolt holes are provided on the mounting base to fix the mounting base on the fan blade by installing bolts in the bolt holes. When the mounting base is not provided with bolt holes, the mounting base can be pasted on the fan blade.

[0175] The elastic element comprises a first elastic element ( Figure 7b The elastic element on the left side of the middle) and the second elastic element ( Figure 7b The slide rail includes a first slide rail ( Figure 7b The left rail) and the second rail ( Figure 7b The slide rail on the right side is 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 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.

[0176] Based on the above structure, the central axis of the inductive device, the central axis of each magnetic device, the central axis of each elastic element, and the central axis of the slide rail are in the same direction. In this way, the inductive device can move in the direction of the central axis of the inductive device when in motion, and normal relative motion between the inductive device and the magnetic device can occur. At this time, in order to make the vibration direction of the inductive device and the swing direction of the blade meet the preset angle range, the central axis direction of the inductive device needs to meet the preset angle range with the swing direction of the blade, for example Figure 7b The central axis direction of the magnetic device in the embodiment may be the Y direction. In practical applications, the damper unit may be mounted on the fan blade according to the constraints in this direction.

[0177] Based on this, Figure 7b The direction in which the magnetic devices are arranged in parallel 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, each elastic element and the inductive device vibrates, driving the sliding holder to reciprocate on the slide rail in the vibration direction of the inductive device, and the magnetic device on the sliding holder and the inductive device move relative to each other in the normal direction. As a result, an induced current will be generated in the energy consumption circuit later. In practical applications, such as Figure 7b As shown, when the first elastic element is compressed, the second elastic element is stretched.

[0178] exist Figure 7b In the structure shown, the normal direction of the inductive device is the Y direction, and the tangent 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 Figure 1 The x direction in the coil is the central axis direction), and the tangent direction of the coil is the direction perpendicular to the central axis direction. Figure 7b As shown, the vibration direction / movement direction of the coil can be the Y direction, and the tangent direction of the coil is the Z direction. When the coil vibrates in the Y direction, the coil cuts the magnetic flux of the magnetic device in the Y direction (the normal direction of the coil). That is, the coil moves relative to the internal magnet group in the normal direction along the Y direction through the spring to cause the magnetic flux to change and generate an induced current.

[0179] It can be understood that the components and structures of the damper units shown above all satisfy the formulas involved in the embodiments of the present application.

[0180] In practical applications, the number of inductive devices in the energy consumption circuit can be preset. Specifically, the number of inductive devices in the energy consumption circuit satisfies a quantity range that enables the energy generated in the energy consumption circuit and the kinetic energy work generated in the damper unit to jointly meet a preset condition. For example, the ratio between the energy generated in the energy consumption circuit and the kinetic energy work generated in the damper unit can be determined as the energy proportion. Based on this, the preset condition can be exemplified as the energy proportion being greater than the proportion threshold.

[0181] 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. 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.

[0182] 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 inductive 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 a 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 the moving elements. For example, Figure 5b As shown, the magnet, magnet holder and slider are the moving elements, then m1 is the sum of the total mass of the magnet, magnet holder and slider, and v is the maximum moving speed of the moving element. c / W mag ≥10%, the vibration reduction device plays a role in increasing the damping effect. If it is less than 10%, it can be increased by increasing N w To increase the energy generated in the energy consumption circuit, 10% is the percentage threshold.

[0183] In practical applications, the number of damper units can also be preset. Specifically, the number of damper units satisfies the range of the number that can make the work of the damper system greater than the work of the aerodynamic damping of the fan blades. The work of the damper system is obtained according to the work of each damper unit in the damper system. For example, the work of the damper system is the sum of the work of each damper unit in the damper system.

[0184] 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.

[0185] 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. Therefore, 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. 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.

[0186] 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].

[0187] Based on a wind blade provided in the above method embodiment, an 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.

[0188] See also Figure 8 As shown in FIG. 1 , this figure is a flow chart of a method for producing a fan blade according to an embodiment of the present application. Figure 8 As shown, the method includes S801-S805:

[0189] S801: Obtaining the blade vibration frequency of the fan blade;

[0190] S802: determining the natural frequency of a target system according to the blade vibration frequency and the frequency deviation range of the fan blade, and selecting an elastic element according to 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;

[0191] S803: 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;

[0192] S804: providing an energy consumption circuit as a loop and including an energy consumption device and the inductive device connected to each other, and providing a damper unit including the energy consumption circuit, the magnetic device and the elastic element;

[0193] S805: A damper system is arranged 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 relation, so that the target system in the damper unit resonates with the fan blade, thereby causing relative movement between the magnetic device and the inductive device in the damper unit.

[0194] In a possible implementation manner, selecting an elastic element according to the natural frequency of the target system includes:

[0195] 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.

[0196] As an optional example, the damper system further includes a capacitive device; and the method further includes:

[0197] 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;

[0198] The energy consumption device and the inductive device in the energy consumption circuit are connected to the capacitive device.

[0199] In a possible implementation, selecting the inductive device and the capacitive device according to the resonant frequency of the energy consumption circuit includes:

[0200] Determining the inductance value and the capacitance value according to the resonant frequency of the energy consumption circuit;

[0201] The inductive device is selected according to the inductance value, and the capacitive device is selected according to the capacitance value.

[0202] As an optional example, the damper system is provided on the fan blade, comprising:

[0203] determining a blade flutter vibration mode of the fan blade;

[0204] Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode;

[0205] 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;

[0206] Determining the distance between the damper system and the tip of the fan blade according to the blade swing vibration mode includes:

[0207] 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;

[0208] 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;

[0209] The first distance value is smaller than the second distance value.

[0210] 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.

[0211] In practical applications, the blades can be produced according to the method for producing the wind turbine blades described in the above embodiment. For example, a wind turbine has a 90m long wind turbine blade, and the wind turbine blade has negative damping in the wind speed range of 11-13m / s, and the vibration response amplitude of the swing direction of the wind turbine blade is large in this wind speed range. Moreover, the vibration mode of the wind turbine blade is a first-order swing vibration, and the blade vibration frequency of the wind turbine blade is 0.5Hz. Strong self-excited vibration will reduce the operating life of the wind turbine equipment.

[0212] by Figure 4a Taking the structure shown in the figure as an example, the vibration mode of the fan blade is a 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, volume of a single magnet v =2×10 -6 m 3 , the total weight of the magnet set and the sliding cage m =2.5kg. 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 =35N·m -1 When the blade vibration frequency is 0.5Hz, the resonant damping unit is the dynamic vibration absorber of the blade, and the fan blade and the damper system resonate. In order to make the energy consumption circuit resonate, so that the resonant frequency is the same as the blade vibration frequency and the natural frequency of the target system, select L =2.84e-5H, C =3560F, R=1Ω.

[0213] See also Fig. 9 , Fig. 9 A schematic diagram of a blade damping ratio provided in an embodiment of the present application. After the damper system is installed in the fan blade, the variation law of the fan blade damping ratio at various wind speeds is as follows: Fig. 9 As shown. Fig. 9 It can be seen that when the damper system is not installed, the wind turbine blades have negative damping in the wind speed range of 11-13m / s; after the damper system is installed, the negative damping range of the wind turbine blades disappears, which improves the stability of the wind turbine generator set.

[0214] In a possible implementation, an embodiment of the present application further provides a wind turbine, wherein the wind turbine includes the wind turbine blades described in any one of the above embodiments.

[0215] In a possible implementation, an embodiment of the present application further 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;

[0216] The damper unit includes an energy consumption circuit, a magnetic device and an elastic element;

[0217] The energy consumption circuit is a loop including connected energy consumption devices and inductive devices;

[0218] 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;

[0219] 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.

[0220] 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.

[0221] 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.

[0222] As an optional example, the damper unit in the damper system may be Figure 4a-Figure 7b The damper unit shown here is not intended to be limiting.

[0223] It can be understood 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.

[0224] It can be known from the description of the above implementation mode that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., including several 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 the various embodiments of the present application or certain parts of the embodiments.

[0225] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the system part description.

[0226] It should also be noted that, in this article, the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0227] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those 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 will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fan blade, characterized in that: 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, characterized in that: 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, characterized in that: 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 fan blade according to claim 1, characterized in that: 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, so that normal relative motion or tangential relative motion occurs between the magnetic device and the inductive device.

5. The fan blade according to claim 1, characterized in that: 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 fan blade according to claim 1, characterized in that: 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 fan blade according to claim 1, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: When there are multiple magnetic devices in the damper unit, the multiple magnetic devices are arranged in parallel.

13. The fan blade according to claim 12, characterized in that: 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 fan blade according to any one of claims 1 to 7, characterized in that: 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 fan blade according to claim 3, characterized in that: 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 fan blade according to claim 3 or 15, characterized in that: 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, characterized in that: 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, characterized in that 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, characterized in that 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, characterized in that 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, characterized in that 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, characterized in that: The wind turbine comprises the wind turbine blade according to any one of claims 1 to 16.

23. A damper system, characterized in that: 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 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; 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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