A graded variable damping and variable stiffness pendulum damping device and its vibration reduction configuration method

Abstract

The present invention provides a graded variable damping and variable stiffness pendulum damping device and a vibration reduction configuration method. The device includes a damping mounting frame, a single mass block, a vertical guide, a nonlinear damping unit, a stiffness adjustment unit, and a linear damping unit. The lower permanent magnet assembly or lower conductor assembly of the linear damping unit is horizontally limited and vertically decoupled from the single mass block. The method includes determining the swing arm length, horizontal limit displacement, and vertical limit displacement of the single mass block, as well as the optimal damping ratio of the linear damping unit, setting the optimal damping coefficient determined by the optimal damping ratio as the basic damping coefficient, and adjusting the nonlinear damping coefficient based on the basic damping coefficient through the nonlinear damping unit; and configuring the preset horizontal displacement and preset vertical displacement of the single mass block according to the horizontal limit displacement of the single mass block. The present invention has the advantages of ensuring the stability of the damping coefficient at small amplitudes and providing sufficient damping under extreme conditions.

Description

Technical Field

[0001] The present invention relates to the field of vibration reduction and damping, and in particular to a graded variable damping and variable stiffness pendulum damping device and a vibration reduction configuration method thereof. Background Art

[0002] High-rise buildings and wind turbine towers vibrate significantly and in random directions under strong winds and earthquakes. For these structures, pendulum tuned mass dampers (PTMDs) are ideal energy-absorbing and vibration-reducing devices. Existing PTMDs typically use damping elements such as oil dampers and eddy current dampers. Traditional eddy current PTMDs, however, have a mass with a permanent magnet at the bottom and a conductive plate below it. The gap between the permanent magnet and the conductive plate is constant, resulting in a constant damping coefficient. This allows for easy damping and uniform energy dissipation. However, when the structure is subjected to extreme conditions and large oscillations, this may not be sufficient to rapidly damp the amplitude, resulting in prolonged oscillations. The PTMD's mass can easily exceed its amplitude limit, potentially colliding with the controlled structure (e.g., the PTMD mass inside the tower colliding with the tower wall). This can cause the PTMD to detune, damage the controlled structure, and lead to system instability or performance degradation. At the same time, the control bandwidth of linear PTMD (usually expressed as linear stiffness) is narrow, and its control effect is limited for structures with time-varying dynamic characteristics or multi-order mode participation.

[0003] To address these technical issues, existing approaches employ PTMDs with nonlinear damping forces or nonlinear stiffness. PTMDs with nonlinear damping forces achieve a nonlinear variation of the damping coefficient with the mass's swing amplitude through the relative motion of the mass. However, existing PTMDs with nonlinear damping forces exhibit nonlinear damping coefficients at small displacement amplitudes, resulting in poor vibration reduction performance at small amplitudes. This leads to poor smoothness in the oscillation attenuation process, unstable system response, and inferior energy dissipation compared to traditional linear PTMDs. PTMDs with nonlinear stiffness exhibit a nonlinear stiffness coefficient with increasing amplitude, and their stiffness coefficients are proportional to the square of the amplitude displacement. They offer a wider control bandwidth, but their robustness is highly dependent on the design of nonlinear mechanisms (such as bistability and negative stiffness). In contrast, linear PTMDs offer more predictable robustness at a single frequency under strict tuning conditions. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a graded variable damping and variable stiffness pendulum damping device and its vibration reduction configuration method, which can ensure the stability of the damping coefficient at small amplitudes and provide sufficient energy dissipation capacity under extreme conditions.

[0005] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0006] A graded variable damping and variable stiffness pendulum damping device comprises a damping mounting frame, a single mass block swingably mounted on the damping mounting frame, a plurality of vertical guides passing through the single mass block, a nonlinear damping unit and a stiffness adjustment unit arranged between the single mass block and the vertical guides, and a linear damping unit arranged below the single mass block, wherein the linear damping unit comprises a lower permanent magnet assembly and a lower conductor assembly which are relatively arranged and have a constant gap, the lower permanent magnet assembly or the lower conductor assembly being horizontally limited and vertically decoupled from the single mass block by the vertical guides; the nonlinear damping unit generates nonlinear eddy current damping when the single mass block swings to a first critical height, and the linear damping unit always generates linear eddy current damping when the single mass block swings; and the stiffness adjustment unit generates nonlinear stiffness when the single mass block swings to a second critical height.

[0007] As a further improvement of the above technical solution:

[0008] A linear damping gap is left between the single mass block and the lower permanent magnet assembly. When the single mass block moves from an initial state to a state where the linear damping gap is 0, the lower permanent magnet assembly and the lower conductor assembly move in parallel to generate linear damping; when the single mass block continues to move upward, the nonlinear damping unit generates nonlinear eddy current damping.

[0009] The nonlinear damping unit includes an upper permanent magnet group and an upper conductor plate. The upper permanent magnet group is arranged at the upper end of the vertical guide member, and the upper conductor plate is arranged in a through hole of the vertical guide member of the single mass block. When the upper conductor plate moves to the upper permanent magnet group, it cuts the magnetic flux lines to generate eddy currents. The first critical height is the initial distance between the lower end surface of the upper permanent magnet group and the upper end surface of the upper conductor plate. The first critical height is equal to the linear damping gap of the single mass block in the initial state. The sum of the linear damping gap of the single mass block in the initial state and the axial length of the upper permanent magnet group is greater than the vertical limit displacement of the single mass block. The actual horizontal displacement of the single mass block and the damping coefficient of the damping device satisfy the following relationship:

[0010]

[0011] in, is the damping coefficient of the damping device, is the optimal damping coefficient of the linear damping unit, The nonlinear damping coefficient generated by cutting the upper permanent magnet group on the upper conductor plate is: is the preset horizontal displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines, is the actual horizontal displacement of the single mass block, is the swing arm length of the single mass block, is the preset vertical displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines, is the preset axial length of the upper permanent magnet group, is the actual vertical displacement of the single mass block.

[0012] The stiffness adjustment unit includes an adjustment spring and a limiting portion that cooperates with the adjustment spring. The adjustment spring is arranged at the upper end portion of the vertical guide member, and the limiting portion is the upper end surface of the single mass block. The second critical height is the initial distance between the lower end surface of the adjustment spring and the upper end surface of the single mass block. When the single mass block swings to the second critical height, the upper end surface of the single mass block contacts the adjustment spring and generates nonlinear stiffness. The sum of the second critical height and the axial length of the adjustment spring is greater than the vertical limit displacement of the single mass block.

[0013] The actual horizontal displacement of the single mass block and the stiffness coefficient of the damping device satisfy the following relationship:

[0014]

[0015] in, is the stiffness coefficient of the damping device, is the optimal stiffness coefficient of a single mass block, To adjust the spring stiffness coefficient, is the actual horizontal displacement of the single mass block, is the preset horizontal displacement when the upper end surface of the single mass block begins to contact the adjustment spring, is the swing arm length of the single mass block, is the preset vertical displacement when the upper end surface of the single mass begins to contact the adjustment spring, To adjust the preset axial length of the spring, is the actual vertical displacement of the single mass block.

[0016] The nonlinear damping unit and the stiffness adjustment unit are alternately arranged along the periphery of the single mass block; and the second critical height is greater than or equal to the first critical height.

[0017] A multi-directional guide assembly is provided between the lower permanent magnet assembly and the lower conductor assembly to ensure that the gap between the two remains unchanged. The multi-directional guide assembly includes two sets of guide rail components that are cross-arranged and slide relative to each other. The lower permanent magnet assembly is slidably connected to the guide rail component located on the upper part, and the guide rail component located on the lower part is fixedly installed on the lower conductor assembly.

[0018] A vibration reduction configuration method for the aforementioned graded variable damping and variable stiffness pendulum damping device comprises:

[0019] According to the mass of the single mass , modal quality of the target mode of the controlled structure Calculate mass ratio , according to the mass ratio Determine the swing arm length of a single mass block , the optimal damping ratio of the linear damping unit ;

[0020] Determination of the horizontal limit displacement of a single mass block , according to the swing arm length of the single mass block and the horizontal limit displacement of the single mass block Determine the vertical limit displacement of a single mass block ;

[0021] According to the optimal damping ratio of the linear damping element Calculate the optimal damping coefficient of the linear damping element , the optimal damping coefficient of the linear damping unit Set as the basic damping coefficient; adjust any one or more of the initial distance between the upper permanent magnet group and the upper conductor plate in the nonlinear damping unit, the axial length of the upper conductor plate, the axial length of the upper permanent magnet group, the number of permanent magnets in the upper permanent magnet group, and the permanent magnet arrangement parameters, so that the nonlinear damping coefficient generated by the upper conductor plate cutting the upper permanent magnet group is adjusted based on the basic damping coefficient ;

[0022] According to the horizontal limit displacement of the single mass block Configure the preset horizontal displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines , and then determine the preset vertical displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines ;

[0023] According to the horizontal limit displacement of the single mass block Determine the preset horizontal displacement at which the upper part of the single mass begins to contact the adjustment spring , and then determine the preset vertical displacement when the upper end surface of the single mass block begins to contact the adjustment spring .

[0024] The swing arm length of the single mass block The calculation expression is:

[0025]

[0026]

[0027]

[0028] in, is the swing arm length of the single mass block, is the vibration frequency of the single mass block, is the acceleration due to gravity, is the frequency of the target mode of the controlled structure, is the ratio between the mass of the single mass block and the modal mass of the target mode of the controlled structure, is the mass of the single mass block, is the modal mass of the target mode of the controlled structure;

[0029] The damping coefficient of the linear damping unit The calculation expression is:

[0030]

[0031]

[0032] in, is the optimal damping coefficient of the linear damping unit, is the optimal damping ratio of the damping device, is the vibration frequency of the single mass block, is the mass of the single mass block, is the ratio between the mass of the single mass block and the modal mass of the target mode of the controlled structure, The preset coefficient is in the range of (0,1].

[0033] Compared with the prior art, the advantages of the present invention are:

[0034] The present invention provides a tuned damper with graded variable damping and variable stiffness through ingenious structural design, that is, the applicability of the damping device is expanded by graded linear damping and nonlinear damping, linear stiffness and nonlinear stiffness, thereby realizing graded changes in the damping coefficient and the stiffness coefficient, that is, the damper mass block exhibits linear damping for small amplitudes and nonlinear damping for large amplitudes, thereby achieving faster attenuation of large oscillations to convert them into linear damping sections, which effectively improves the stability and practicality of the vibration control of the damper; at the same time, the damping characteristics or stiffness coefficient can be switched under different working conditions, which not only ensures the stability of the damping coefficient at small amplitudes, but also provides sufficient energy dissipation capacity under extreme conditions to adapt to conventional load conditions and extreme load conditions.

[0035] This invention combines the advantages of both linear and nonlinear damping, while also offering the benefits of both linear and nonlinear stiffness damping devices. It achieves independent adjustment of stiffness and damping within the same damping device. Under extreme loads, the nonlinear damping unit exhibits broadband energy dissipation, while the stiffness adjustment unit further prevents collisions caused by extreme shaking of the single mass. This achieves dual vibration reduction from both stiffness and damping adjustment perspectives, ensuring effective damping and vibration reduction.

[0036] The method of the present invention first determines the swing length of the swing arm of the single mass block, the optimal damping ratio of the linear damping unit, and the horizontal limit displacement and vertical limit displacement of the single mass block based on the mass ratio. Then, the optimal damping coefficient of the linear damping unit determined based on the optimal damping ratio of the linear damping unit is set as the optimal damping coefficient. According to the horizontal limit displacement of the single mass block, any one or more of the initial distance between the upper permanent magnet group and the upper conductor plate in the nonlinear damping unit, the axial length of the upper conductor plate, the axial length of the upper permanent magnet group, the number of permanent magnets in the upper permanent magnet group, and the permanent magnet arrangement parameters are adjusted to adjust the nonlinear damping coefficient generated by the upper conductor plate cutting the upper permanent magnet group. In this way, the damping device of the present invention can adjust the overall damping coefficient of the device by adjusting the nonlinear damping coefficient of the nonlinear damping unit on the basis of the optimal damping coefficient of the linear damping unit, thereby being applicable to effective vibration reduction in situations where the controlled structure vibrates significantly and has a large damping demand.

[0037] At the same time, the present invention configures the horizontal displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines based on the maximum horizontal displacement value of the controlled structure obtained from the dynamic response analysis of the controlled structure under different loads, thereby determining the preset vertical displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines. Based on the horizontal limit displacement, the preset horizontal displacement when the upper portion of the single mass block begins to contact the adjustment spring is determined, thereby determining the preset vertical displacement when the upper end surface of the single mass block begins to contact the adjustment spring. In this way, the optimal setting parameters of each component in the nonlinear damping unit and the stiffness adjustment unit are determined in combination with the actual conditions of the controlled structure, thereby matching the structure of the damping device to achieve optimal configuration, thereby maximizing the damping and vibration reduction effect of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0039] Figure 1 Schematic diagram of the structure of the graded variable damping and variable stiffness pendulum damping device of the present invention;

[0040] Figure 2 Schematic diagram of the exploded structure of the graded variable damping and variable stiffness pendulum damping device of the present invention;

[0041] Figure 3 This is a simplified structural diagram of the graded variable damping and variable stiffness pendulum damping device of the present invention;

[0042] Figure 4 Schematic diagram of the positional relationship between the nonlinear damping unit and the single mass block of the present invention;

[0043] Figure 5 Schematic diagram of the displacement of a single mass block of the present invention;

[0044] Figure 6 It is a structural schematic diagram of the lower permanent magnet assembly of the present invention;

[0045] Figure 7 It is a structural schematic diagram of the multi-directional guide assembly of the present invention;

[0046] Figure 8 is a curve diagram showing the variation of the damping coefficient of the damping device of the present invention with the actual horizontal displacement of the single mass block;

[0047] Figure 9 is a graph showing the change in stiffness coefficient of the damping device of the present invention with the actual horizontal displacement of the single mass block;

[0048] Figure 10 It is a flow chart of the vibration reduction configuration method of the present invention.

[0049] The numbers in the figure represent:

[0050] 1. Damping mounting frame; 2. Single mass block; 21. Mass block back plate; 3. Vertical guide; 31. Guide roller; 4. Nonlinear damping unit; 41. Upper permanent magnet group; 42. Upper conductor plate; 5. Stiffness adjustment unit; 51. Adjustment spring; 52. Limiting part; 6. Linear damping unit; 61. Lower permanent magnet assembly; 611. Lower permanent magnet group; 612. Permanent magnet group back plate; 62. Lower conductor assembly; 621. Lower conductor plate; 7. Multi-directional guide assembly; 71. Guide rail component; 8. Swing arm; 81. Swing arm mounting ring; 9. Linear damping gap. DETAILED DESCRIPTION

[0051] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereby.

[0052] Figures 1 to 7This embodiment of the present invention's pendulum damping device with graded variable damping and stiffness is shown. It can be used to suppress vibrations in large structures such as bridges. In this embodiment, the pendulum damping device with graded variable damping and stiffness includes a damping mounting frame 1, a single mass block 2, a vertical guide 3, a nonlinear damping unit 4, a stiffness adjustment unit 5, and a linear damping unit 6. The single-mass mass 2 is swingably mounted on the damping mounting frame 1 via a swing arm 8. Multiple vertical guides 3 extend through the single-mass mass 2, allowing it to move along the length of the vertical guides 3. A nonlinear damping unit 4 and a stiffness adjustment unit 5 are positioned between the single-mass mass 2 and the vertical guides 3. A linear damping unit 6 is positioned below the single-mass mass 2. The linear damping unit 6 comprises a lower permanent magnet assembly 61 and a lower conductor assembly 62, arranged relative to each other with a constant gap. The lower permanent magnet assembly 61 or the lower conductor assembly 62 is horizontally limited and vertically decoupled from the single-mass mass 2 by the vertical guides 3. This means that when the single-mass mass 2 swings, the lower permanent magnet assembly 61 or the lower conductor assembly 62 synchronizes with the single-mass mass 2 in horizontal displacement only through the vertical guides 3, while the lower permanent magnet assembly 61 or the lower conductor assembly 62 moves relative to the single-mass mass 2 in the vertical direction. This design results in a compact layout and minimal space requirements.

[0053] At the same time, the present invention provides a tuned damper with graded variable damping and variable stiffness through ingenious structural design, that is, the applicability of the damping device can be expanded by graded linear damping and nonlinear damping, linear stiffness and nonlinear stiffness, thereby realizing graded changes in the damping coefficient and the stiffness coefficient, that is, the single mass block 2 of the damper exhibits linear damping for small amplitudes and nonlinear damping for large amplitudes, thereby achieving faster attenuation of large oscillations to convert them into linear damping sections, which effectively improves the stability and practicality of the vibration control of the damper; at the same time, the damping characteristics or stiffness coefficient can be automatically switched under different working conditions, which not only ensures the stability of the damping coefficient at small amplitudes, but also provides sufficient energy dissipation capacity under extreme conditions to adapt to conventional load conditions and extreme load conditions.

[0054] When mass 2 swings to a first critical height, it moves to the nonlinear damping unit 4, generating nonlinear eddy current damping. As mass 2 swings, the gap between its lower permanent magnet assembly 61 and lower conductor assembly 62 remains constant. Linear damping unit 6 continuously generates linear eddy current damping, and the damping coefficient is constant. This means that when mass 2 experiences small displacements, the damping device provides only linear damping. Linear damping provides a stable damping force at small amplitudes, avoiding the low energy consumption and efficiency that can result from excessively low damping force due to nonlinear damping, thereby reducing fatigue cycles in the structure.

[0055] When the displacement amplitude of the single mass block 2 is too large and exceeds the first critical height, the damping coefficient changes nonlinearly with the increase in the displacement amplitude of the single mass block 2 (approximately a quadratic parabola). At this time, the larger the amplitude of the single mass block 2, the damping coefficient increases exponentially. At this time, nonlinear damping quickly attenuates oscillations at large amplitudes, reducing the number of oscillation cycles, thereby reducing fatigue damage to the structure caused by large oscillations.

[0056] At the same time, the nonlinear damping unit 4 and the linear damping unit 6 both cut the magnetic lines of flux to generate eddy currents, and the eddy currents in turn generate an electromagnetic field with the opposite polarity of the magnetic field of the corresponding permanent magnet group itself. The two electromagnetic fields with opposite polarities hinder each other's movement, resulting in an eddy current damping effect that presents nonlinear damping. The single mass block 2 cuts the magnetic lines of flux in the vertical and horizontal movements to generate eddy current heat energy, which is consumed through conduction through the air, etc. Under the action of the eddy current damping effect, the single mass block 2 moves slower and slower in the vertical and horizontal directions, and the angle becomes smaller and smaller until it stops. The vibration energy is finally converted into eddy current heat energy, which can simultaneously achieve maximum energy consumption density and optimal stroke control of the single mass block 2, ensuring the damping and vibration reduction effect.

[0057] The stiffness adjustment unit 5, located between the single mass 2 and the vertical guide 3, generates nonlinear stiffness when the single mass 2 swings to a second critical height. The stiffness coefficient of the present invention also varies in stages. When the mass displacement amplitude is less than the second critical height, the stiffness coefficient is approximately constant, meaning that the stiffness coefficient varies little with the displacement amplitude of the single mass 2. However, when the displacement amplitude of the single mass 2 is excessive, exceeding the second critical height, the stiffness coefficient varies nonlinearly with the increase in the displacement amplitude of the single mass 2. In other words, the stiffness coefficient increases exponentially with the increase in the amplitude of the single mass 2. This allows for frequency regulation while limiting the displacement amplitude of the single mass 2, preventing structural overruns and collisions. This effectively prevents the single mass 2 from generating dangerous amplitude movements under extreme loads. Therefore, the combination of nonlinear and linear stiffness of the present invention can, while taking into account the control frequency band, avoid the unpredictability of robustness to a certain extent, significantly alleviating the difficulty of robustness analysis and prediction.

[0058] As can be seen, the present invention combines the advantages of both linear and nonlinear damping, while also leveraging the strengths of both linear and nonlinear stiffness damping devices. It achieves independent adjustment of stiffness and damping within the same damping device. Under extreme loads, the nonlinear damping unit 4 exhibits broadband energy dissipation, while the stiffness adjustment unit 5 further prevents impacts during extreme shaking of the single mass 2. This achieves dual vibration reduction from both stiffness and damping adjustment perspectives, ensuring effective damping.

[0059] like Figure 3As shown, further, a linear damping gap 9 is left between the single mass block 2 and the lower permanent magnet assembly 61. When the single mass block 2 moves from the initial state to the point where the linear damping gap 9 is 0, the lower permanent magnet assembly 61 and the lower conductor assembly 62 move in parallel to generate linear damping; when the single mass block 2 continues to move upward, the nonlinear damping unit 4 generates nonlinear damping in the form of eddy currents, thereby achieving graded variable damping through ingenious structural design.

[0060] like Figure 6 As shown, preferably, the lower permanent magnet assembly 61 includes a lower permanent magnet group 611 and a permanent magnet group back plate 612. The lower permanent magnet group 611 is provided on the bottom end surface of the permanent magnet group back plate 612. The lower permanent magnet group 611 includes a plurality of annular permanent magnets, and the plurality of annular permanent magnets are concentrically arranged. Figure 3 As shown, the upper permanent magnet group 41 includes multiple annular permanent magnets, which are arranged along the axial direction of the vertical guide 3, which ensures that the nonlinear damping unit 4 and the linear damping unit 6 provide the damping device with completely consistent damping coefficients along each vibration direction, further ensuring effective vibration reduction in multiple directions of the device.

[0061] Meanwhile, the lower conductor assembly 62 includes a lower conductor plate 621 . The lower conductor plate 621 and the annular permanent magnet move relative to each other when the single mass block 2 swings, thereby generating a linear eddy current damping force.

[0062] like Figure 3 and Figure 4 As shown, the nonlinear damping unit 4 includes an upper permanent magnet group 41 and an upper conductor plate 42. The upper permanent magnet group 41 is disposed at the upper end of the vertical guide member 3, and the upper conductor plate 42 is disposed within a through-hole of the single mass 2 that penetrates the vertical guide member 3. The first critical height is the initial distance between the lower end surface of the upper permanent magnet group 41 and the upper end surface of the upper conductor plate 42. The first critical height is equal to the linear damping gap 9 of the single mass 2 in its initial state. When the upper conductor plate 42 moves to the upper permanent magnet group 41, that is, when the upper end of the upper conductor plate 42 begins to overlap with the lower end of the upper permanent magnet group 41, the upper conductor plate 42 cuts the magnetic flux lines and generates eddy currents. In this embodiment, the upper conductor plate 42 is an annular conductor plate fixed to the inner wall of the through-hole of the single mass 2.

[0063] In this embodiment, the sum of the linear damping gap 9 and the axial length of the upper permanent magnet group 41 in the initial state of the single mass block 2 is greater than the vertical limit displacement of the single mass block 2, thereby avoiding excessive displacement of the single mass block 2 and ensuring the vibration control effect of the controlled structure.

[0064] In this embodiment, the actual horizontal displacement of the single mass block 2 and the damping coefficient of the damping device satisfy the following relationship:

[0065] (1)

[0066] in, is the damping coefficient of the damping device, is the optimal damping coefficient of the damping device, The nonlinear damping coefficient generated by the upper conductor plate 42 cutting the upper permanent magnet group 41 is: is the preset horizontal displacement of the single mass block 2 when the upper conductor plate 42 begins to cut the magnetic flux lines, is the actual horizontal displacement of the single mass block 2, is the swing length of the swing arm 8 of the single mass block 2, is the preset vertical displacement of the single mass block 2 when the upper conductor plate 42 begins to cut the magnetic flux lines, i.e., the first critical height; is the preset axial length of the upper permanent magnet group 41, is the actual vertical displacement of the single mass block 2.

[0067] like Figure 5 and Figure 8 As shown, the relationship between the actual vertical displacement of the single mass block 2, the actual horizontal displacement of the single mass block and the swing length of the swing arm 8 of the single mass block 2 is: .when 、 hour, , at this time, the linear damping unit 6 always generates linear eddy current damping. 、 hour, At this point, nonlinear damping unit 4 provides nonlinear damping, while linear damping unit 6 continuously generates linear eddy current damping. This results in nonlinear damping whose damping coefficient increases exponentially with increasing amplitude, ensuring a robust vibration damping effect. For example, under normal loads, linear damping unit 6 can provide more stable linear damping. Under extreme loads, the damping coefficient provided by linear damping unit 6 is insufficient, and the vibration response amplitude will exceed the stroke. Nonlinear damping unit 4 can then provide greater nonlinear damping to more quickly limit the vibration response.

[0068] Further, if Figures 1 to 4 As shown, the stiffness adjustment unit 5 includes an adjustment spring 51 and a limiting portion 52 that cooperates with the adjustment spring 51. The adjustment spring 51 is provided at the upper end portion of the vertical guide member 3, and the limiting portion 52 is the upper end surface of the single mass block 2. When the stiffness adjustment unit 5 swings to the second critical height of the single mass block 2, the limiting portion 52 contacts the bottom of the adjustment spring 51 and begins to compress the adjustment spring 51 to generate nonlinear stiffness. At this time, the stiffness coefficient changes nonlinearly with the increase of the displacement amplitude of the single mass block 2, that is, the larger the amplitude of the single mass block 2, the stiffness coefficient of the adjustment spring 51 increases by multiples, thereby changing the frequency. The wider the frequency band, the greater the damper's tolerance to frequency variations and the greater its adaptability. Furthermore, the present invention's combination of linear and nonlinear stiffness can, to a certain extent, mitigate the unpredictability of robustness, reduce the complexity and sensitivity associated with nonlinear design, and significantly ease the difficulty of robustness analysis and prediction, thereby improving the overall robustness and practicality of the system.

[0069] As can be seen, the adjustment spring 51 of this embodiment can effectively modulate the frequency while limiting the range of motion of the single mass 2. Specifically, under extreme loads, the adjustment spring 51 can effectively prevent the single mass 2 from moving at dangerous speeds, providing a final measure of protection to prevent damage to the controlled structure. Furthermore, the adjustment spring 51 exhibits high reliability, low maintenance requirements, and low cost. In this embodiment, the adjustment spring 51 can be configured as needed, such as a linear spring or a progressive spring. When the adjustment spring 51 is configured as a progressive spring, the stiffness coefficient of the damping device varies unevenly with the amount of compression, achieving frequency modulation.

[0070] The core mechanism of vibration control in this invention is to dissipate energy through the nonlinear damping unit 4 and the linear damping unit 6 to reduce vibration amplitude, while the adjustable spring 51 acts as a frequency modulation measure and a final protection measure under extreme loads. Nonlinear damping controls vibration by dynamically adjusting the damping coefficient, while the adjustable spring 51 ensures that displacement does not exceed a critical threshold. The coordinated use of the nonlinear damping unit 4 and the adjustable spring 51 achieves both vibration control under normal loads and structural safety under extreme loads.

[0071] In this embodiment, the actual horizontal displacement of the single mass block 2 and the stiffness coefficient of the damping device satisfy the following relationship:

[0072] (2)

[0073] in, is the stiffness coefficient of the damping device, is the optimal stiffness coefficient of a single mass block, To adjust the stiffness coefficient of spring 51, is the actual horizontal displacement of the single mass block 2, is the preset horizontal displacement when the upper end surface of the single mass block 2 begins to contact the adjustment spring 51, is the swing length of the swing arm 8 of the single mass block 2, is the preset vertical displacement when the upper end surface of the single mass block 2 begins to contact the adjustment spring 51, that is, the second critical height; To adjust the preset axial length of the spring 51.

[0074] like Figure 9 As shown, when ， hour, , the stiffness coefficient is approximately constant, and the stiffness coefficient changes slightly with the displacement amplitude of the single mass block 2. , hour, The stiffness coefficient increases nonlinearly with the increase of the displacement amplitude of the single mass 2, that is, the larger the amplitude of the single mass 2, the stiffness coefficient increases exponentially. Preferably, the present invention can further limit the damper stroke by changing the stiffness parameter to avoid collision.

[0075] Preferably, if Figure 1 and Figure 2 As shown, the nonlinear damping units 4 and the stiffness adjustment units 5 are alternately arranged along the periphery of the single mass 2. The initial distance between the upper end surface of the single mass 2 and the lower end of the adjustment spring 51 is a second critical height, which is greater than or equal to the first critical height. At this point, the damper primarily relies on nonlinear damping to dissipate energy. The damper acts as a nonlinear energy sink, with efficient vibration absorption and energy dissipation capabilities, as well as broadband, passive, and lightweight characteristics.

[0076] like Figure 7 As shown, a multi-directional guide assembly 7 is provided between the lower permanent magnet assembly 61 and the lower conductor assembly 62. The multi-directional guide assembly 7 includes two sets of guide rail components 71 arranged in a cross-direction and sliding relationship with each other. The lower permanent magnet assembly 61 is fixedly connected to the sliding block of the upper guide rail component 71 to slide along the slide rail of the guide rail component 71. The lower guide rail component 71 is fixedly mounted to the lower conductor assembly 62. At this time, the gap between the lower permanent magnet assembly 61 and the lower conductor assembly 62 remains unchanged, thereby ensuring that the linear damping unit 6 always cuts the magnetic flux lines and provides linear damping when the single mass block 2 swings. In this embodiment, the two sets of guide rail components 71 are vertically cross-directed to enable the single mass block 2 to swing in two vertical directions.

[0077] Furthermore, a guide roller 31 is provided between the vertical guide member 3 of the adjustment spring 51 and the through hole of the single mass block 2 to ensure effective sliding cooperation between the single mass block 2 and the vertical guide member 3 and ensure smooth and safe swinging of the single mass block 2.

[0078] Preferably, the upper and lower end surfaces of the single mass block 2 are provided with a mass block back plate 21, and the single mass block 2 and the mass block back plate 21 are connected by screws to facilitate the disassembly and installation of components. Figure 1 As shown, the upper end of the swing arm 8 is detachably mounted on the damping mounting frame 1 through the swing arm mounting ring 81, and the lower end of the swing arm 8 is detachably mounted on the mass block back plate 21 on the upper end surface of the single mass block 2 through the swing arm mounting ring 81.

[0079] In this embodiment, the specific implementation process of the graded variable damping and variable stiffness pendulum damping device is as follows: When the controlled structure vibrates, the single mass 2 suspended on the damping mounting frame 1 swings. Vertically, the single mass 2 moves up and down along the vertical guide 3. Horizontally, the single mass 2 and the lower permanent magnet assembly 611 slide parallel to the guide rail component 71, and the gap between the lower permanent magnet assembly 611 and the lower conductive plate 621 remains unchanged. At this point, the damping coefficient of the damping device is constant, exhibiting linear damping. When the single mass 2 moves vertically along the vertical guide 3 to a first critical height, the upper conductive plate 42 of the single mass 2 and the upper permanent magnet assembly 41 mounted on the vertical guide 3 begin to cut through the magnetic flux lines, generating eddy current damping. The damping coefficient is not constant, exhibiting nonlinear damping. When the single mass 2 moves vertically along the vertical guide 3 to a second critical height, the adjustment spring 51 mounted on the vertical guide 3 can achieve multi-stage stiffness variation. The present invention achieves vibration control of the damper and improves energy dissipation efficiency by passively changing the damping coefficient and the stiffness coefficient along with the swing amplitude through graded linear damping and nonlinear damping, graded linear stiffness and nonlinear stiffness.

[0080] like Figure 10 As shown, the vibration reduction configuration method of the graded variable damping and variable stiffness pendulum damping device of this embodiment as described above, the method of the present invention first determines the swing length of the swing arm 8 of the single mass block 2 and the optimal damping ratio of the linear damping unit 6 according to the mass ratio, determines the vertical limit displacement of the single mass block 2 according to the swing length of the swing arm 8 of the single mass block 2 and the horizontal limit displacement of the single mass block 2, then sets the optimal damping coefficient of the linear damping unit 6 determined according to the optimal damping ratio of the linear damping unit 6 as the basic damping coefficient, and adjusts the position between the upper permanent magnet group 41 and the upper conductor plate 42 in the nonlinear damping unit 4 according to the horizontal limit displacement of the single mass block 2. Any one or more of the parameters of the initial distance, the axial length of the upper conductor plate 42, the axial length of the upper permanent magnet group 41, the number of permanent magnets in the upper permanent magnet group 41, and the permanent magnet arrangement method are adjusted so that the nonlinear damping coefficient generated by the upper conductor plate 42 cutting the upper permanent magnet group 41 is adjusted on the basis of the basic damping coefficient, so that the damping device of the present invention can accurately and quickly adjust the nonlinear damping coefficient through the nonlinear damping unit 4 on the basis of the optimal damping coefficient of the linear damping unit 6, thereby realizing the adjustment of the overall damping coefficient of the device, so that it can be applied to effective vibration reduction in occasions where the controlled structure vibrates significantly and the damping demand is large.

[0081] At the same time, the present invention configures the preset horizontal displacement of the single mass 2 when the upper conductor plate 42 begins to cut the magnetic flux lines based on the horizontal limit displacement of the single mass 2, thereby determining the preset vertical displacement of the single mass 2 when the upper conductor plate 42 begins to cut the magnetic flux lines. At the same time, the preset horizontal displacement of the single mass 2 when the upper portion of the single mass 2 begins to contact the adjustment spring 51 is determined based on the horizontal limit displacement of the single mass 2, thereby determining the preset vertical displacement when the upper end surface of the single mass 2 begins to contact the adjustment spring 51. Thus, the optimal setting parameters of each component in the nonlinear damping unit 4 and the stiffness adjustment unit 5 are determined in combination with the actual conditions of the controlled structure, thereby achieving an optimized configuration that matches the structure of the damping device and maximizes the damping and vibration reduction effect of the device.

[0082] For example, when a wind turbine operates under extreme load conditions, the nonlinear damping unit 4 can be prioritized for enhancing its energy dissipation capacity by adjusting its nonlinear damping coefficient (e.g., optimizing the number and arrangement of permanent magnets in the upper permanent magnet group 41). Adjusting the nonlinear damping unit 4 significantly reduces the controlled structure's travel limit, and even when it does, its residual impact energy is significantly reduced, significantly reducing its reliance on the adjustment spring 51 and the impact load. Furthermore, when vibration displacement inevitably reaches its limit, the configured stiffness adjustment unit 5 (adjustment spring 51) can achieve a "soft landing" rather than a rigid collision by setting the progressive stiffness. The combined configuration of the nonlinear damping unit 4 and the stiffness adjustment unit 5 allows an optimized nonlinear damping unit 4 to reduce the burden on the stiffness adjustment unit 5, while a properly configured stiffness adjustment unit 5 provides safety redundancy for the damping system, achieving an optimal balance between travel limitations and vibration control requirements.

[0083] See also Figure 10 The vibration reduction configuration method of the above-mentioned graded variable damping and variable stiffness pendulum damping device of this embodiment specifically includes:

[0084] Step 1), according to the mass of the single mass block 2 , modal quality of the target mode of the controlled structure Calculate mass ratio , according to the mass ratio Determine the length of the swing arm 8 of the single mass block 2 , the optimal damping ratio of the linear damping unit 6 .

[0085] Among them, the swing length of the swing arm 8 of the single mass block 2 is determined as follows: The principle can be: according to the mass of the single mass block 2 Modal quality of the target mode of the controlled structure The ratio between , and the frequency of the target mode of the controlled structure Calculate the vibration frequency of the single mass block 2 , according to the vibration frequency of the single mass block 2 Determine the length of the swing arm 8 of the single mass block 2 。 The swing length of the swing arm 8 of the single mass block 2 can be calculated according to the following formula: :

[0086] (3)

[0087] (4)

[0088] (5)

[0089] in, is the swing length of the swing arm 8 of the single mass block 2, is the vibration frequency of the single mass block 2, is the acceleration due to gravity, is the frequency of the target mode of the controlled structure, is the ratio between the mass of the single mass block 2 and the modal mass of the target mode of the controlled structure, is the mass of the single mass block 2, is the modal mass of the target mode of the controlled structure.

[0090] Mass of single mass block 2 It can be determined according to the overall load-bearing capacity of the controlled structure and the local load-bearing capacity of the installation location, and the installation space of the controlled structure. For example, the mass of the single mass block 2 Set within the bearing capacity of the controlled structure, and set a single mass block 2 that meets the installation requirements according to the installation space of the controlled structure. Modal mass of the target mode of the controlled structure Before the damping device is set, it can be determined according to the type of controlled structure. Modal quality of the target mode of the controlled structure The ratio between them can be set according to energy consumption requirements, such as The larger the value, the more energy the damper can absorb and dissipate, and the better the vibration reduction effect. is the natural frequency of the controlled structure.

[0091] In this embodiment, the optimal damping ratio of the linear damping unit 6 is According to the mass ratio , and the energy consumption demand of the controlled structure is determined. For example, the optimal damping ratio of the linear damping unit 6 is The fixed point method can be used to determine the optimal damping ratio of the linear damping unit 6. The principle of the fixed point method is to convert the recursive formula of the series into the form of a geometric series or an arithmetic series, thereby simplifying the solution of the problem. It can be applied to occasions where the energy consumption demand of the controlled structure is low, and quickly obtain the optimal damping ratio of the linear damping unit 6 .

[0092] The fixed point method is used to calculate and confirm the optimal damping ratio of the linear damping unit 6 The optimal formula is:

[0093] (6)

[0094] in, is the optimal damping ratio of the linear damping unit 6, The preset coefficient is in the range of (0,1].

[0095] When the When the traditional fixed point method is used to calculate the optimal damping ratio of the linear damping unit 6, Preferably, the optimal damping ratio of the linear damping unit 6 is It can also be determined by the improved fixed point method, for example , that is, according to Determine the optimal damping ratio , which can further improve the convergence speed and accuracy of the iteration.

[0096] More preferably, the optimal damping ratio of the linear damping unit 6 is It can also be determined by the maximum modal damping ratio method, for example, ,according to Determine the optimal damping ratio , further improve the optimal damping ratio of the linear damping unit 6 The accuracy of the linear damping unit 6 is improved, thereby further improving the energy dissipation capacity of the structure. When the preset coefficient Select large, optimal damping ratio of linear damping unit 6 The accuracy is higher and the damping and vibration reduction ability of the device is better.

[0097] In other embodiments, the optimal damping ratio of the linear damping unit 6 is It can also be determined in other ways according to needs.

[0098] In this embodiment, the horizontal limit displacement of the single mass block 2 is measured , according to the swing length of the swing arm 8 of the single mass block 2 and the horizontal limit displacement of the single mass block 2 Determine the vertical limit displacement of single mass block 2 The travel limit of the single mass block 2 includes the horizontal limit displacement of the single mass block 2 and vertical limit displacement Horizontal limit displacement It can be determined based on the actual installation space inside the controlled structure. For example, the standard is that the single mass block 2 does not touch the internal components of the controlled structure when it swings to the extreme position in the horizontal direction. The safety distance between the extreme swing position of the single mass block 2 and the interior of the controlled structure can also be pre-set based on actual conditions.

[0099] More preferably, the horizontal limit displacement of the single mass block 2 is obtained according to the response analysis of the controlled structure under different loads. Specifically, the horizontal displacement of the controlled structure under different loads is obtained through response analysis, and the maximum horizontal displacement under different loads is determined as the horizontal limit displacement of the single mass block 2.

[0100] Afterwards, the horizontal limit displacement of the single mass block 2 can be , the swing length of the swing arm 8 of the single mass block 2 Determine the vertical limit displacement of the single mass block 2 according to the following formula: :

[0101] (7)

[0102] Preferably, in addition to determining the above parameters, other parameters can also be set, for example, the initial stiffness of the damping device can also be determined. The initial stiffness of the damping device It can be determined according to the following formula:

[0103] (8)

[0104] In this embodiment, the swing length of the swing arm 8 of the single mass block 2 is much greater than the actual horizontal displacement of the single mass block 2, that is, , at this time, the initial stiffness of the damping device is the simple pendulum stiffness, which can be obtained based on the swing length of the swing arm 8 of the single mass block 2 , the mass of single mass block 2 The initial stiffness of the damping device is determined by the following formula: :

[0105] (9)

[0106] Step 2), according to the optimal damping ratio of the linear damping unit 6 Calculate the optimal damping coefficient of linear damping unit 6 , the optimal damping coefficient of the linear damping unit 6 Set as the basic damping coefficient; adjust any one or more of the initial distance between the upper permanent magnet group 41 and the upper conductor plate 42 in the nonlinear damping unit 4, the axial length of the upper conductor plate 42, the axial length of the upper permanent magnet group 41, the number of permanent magnets in the upper permanent magnet group 41, and the permanent magnet arrangement parameters, so as to adjust the nonlinear damping coefficient generated by the upper conductor plate 42 cutting the upper permanent magnet group 41 based on the basic damping coefficient The damping device of the present invention can accurately and quickly adjust the nonlinear damping coefficient through the nonlinear damping unit 4 on the basis of the basic damping coefficient of the linear damping unit 6, thereby realizing the adjustment of the overall damping coefficient of the device, and thus can be applied to effectively reduce vibration in situations where the controlled structure vibrates significantly and has a large damping demand.

[0107] Furthermore, the optimal damping coefficient of the linear damping unit 6 is The optimal damping ratio of the linear damping unit 6 can be , the vibration frequency of the single mass block 2 , and the mass of the single mass block 2 Determine to quickly obtain the optimal damping coefficient of the linear damping unit 6 according to the actual situation of the single mass block 2 , meet the damping and vibration reduction requirements of different controlled structures, thereby providing the precise optimal damping coefficient of the damping device of the present invention The optimal damping coefficient of the linear damping unit 6 can be determined according to the following formula: :

[0108] (10)

[0109] In this embodiment, the mass of the single mass block 2 is a fixed value, the vibration frequency of the single mass block 2 and the optimal damping ratio of the linear damping unit 6 It can be determined using formula (3) and formula (6).

[0110] Preferably, the nonlinear damping coefficient of the nonlinear damping unit 4 is It can be set according to the needs of the actual project, such as the optimal damping coefficient of the linear damping unit 6 Based on the horizontal limit displacement of the single mass block 2 Nonlinear damping coefficient Afterwards, the nonlinear damping coefficient of the nonlinear damping unit 4 can be adjusted by adjusting any one or more of the initial distance between the upper permanent magnet group 41 and the upper conductor plate 42, the axial length of the upper conductor plate 42, the axial size of the upper permanent magnet group 41, the number of permanent magnets in the upper permanent magnet group 41, the arrangement of the permanent magnets, and the material of the permanent magnets. to the optimal value.

[0111] In step 3), the horizontal limit displacement of the single mass block 2 can be Configure the preset horizontal displacement of the single mass block 2 when the upper conductor plate 42 begins to cut the magnetic flux lines , and then determine the preset vertical displacement of the single mass block 2 when the upper conductor plate 42 begins to cut the magnetic flux lines .

[0112] The preset horizontal displacement of the single mass block 2 when the upper conductor plate 42 begins to cut the magnetic flux lines The horizontal limit displacement of the single mass block 2 can be set Near or slightly above the horizontal limit displacement , that is, setting the horizontal limit displacement of the single mass block 2 falls within the linear damping region of the damping device (i.e. ), thereby ensuring that the behavior of the damping device under normal operating conditions of the controlled structure (such as a wind turbine) is closer to that of an ideal linear tuned mass damper, so as to most effectively suppress steady-state vibrations of a specific frequency or conventional vibrations caused by continuous wind loads.

[0113] Sure After that, when the horizontal displacement of the single mass block 2 reaches When the vertical displacement of the single mass block 2 is for , so according to the formula Determine the single mass block 2 , where for , for .

[0114] Furthermore, the nonlinear damping coefficient Size requirements, and vertical space limitations ( ) Set the preset axial length of the upper permanent magnet group 41 . Thus, the optimal damping coefficient of the linear damping unit 6 is guaranteed in the face of extreme environments. and the nonlinear damping coefficient of the linear damping unit 6 The damping provided by the combination satisfies , so that the controlled structure can effectively reduce vibration in extreme environments.

[0115] In this embodiment, the horizontal limit displacement of the single mass block 2 can also be Determine the preset horizontal displacement when the upper part of the single mass block 2 begins to contact the adjustment spring 51 Thus, according to the above steps, the preset vertical displacement of the single mass block 2 when the single mass block 2 starts to cut the magnetic flux line at the upper conductor plate 42 can be determined respectively. and the preset horizontal displacement when the upper portion of the single mass block 2 begins to contact the adjustment spring 51 .

[0116] Specifically, the preset horizontal displacement when the upper portion of the single mass block 2 begins to contact the adjustment spring 51 , satisfy , so that before the single mass 2 hits the physical limiter 52 of the damping device (hard stop), the adjustment spring 51 is activated to provide a "soft" buffer to avoid the impact and potential damage caused by a rigid collision. It can cooperate with the mass, stiffness, and nonlinear damping of the damping device to ensure that after the adjustment spring 51 is triggered, the entire system can effectively dissipate energy and control the displacement of the controlled structure within a safe range. .

[0117] According to the preset horizontal displacement Then determine the preset vertical displacement when the upper end surface of the single mass block 2 begins to contact the adjustment spring 51 When it is determined After that, when the horizontal displacement of the single mass block 2 reaches At this time, the vertical displacement of the single mass block 2 for , so according to the formula Sure , where for , for .

[0118] Furthermore, the axial length of the spring 51 is adjusted According to the vertical space limitation ( ) Set up, ensure When facing extreme environments, adjust the axial length of spring 51 It can provide sufficient reaction force to effectively limit the movement of the damping device, so that the optimal damping coefficient of the linear damping unit 6 can be achieved under extreme conditions. and the nonlinear damping coefficient of the linear damping unit 6 While providing damping, the spring 51 is further adjusted to prevent the single mass 2 from moving at a dangerous amplitude under extreme loads. Adjust the axial length of the spring 51 The precise value of can be ultimately determined and optimized through system modeling, dynamic simulation, and response analysis of wind turbines under various operating conditions (including extreme conditions).

[0119] The present invention does not limit the specific time sequence of the steps, and in practice, the steps can also be performed in other orders, such as determining the horizontal limit displacement of the single mass block in step 1). After that, the preset horizontal displacement of the single mass block in step 3) can also be executed synchronously to determine and preset vertical displacement , and the preset horizontal displacement of the single mass block 2 and preset vertical displacement .

[0120] Figure 8 and Figure 9 The graph showing the variation of the damping coefficient and stiffness coefficient of the damping device of the specific embodiment with the actual horizontal displacement of the single mass block 2 is shown. Specifically:

[0121] Figure 8 The damping coefficient of the damping device obtained in the specific embodiment changes with the actual horizontal displacement of the single mass block 2 It can be seen that when hour, , at this time, the linear damping unit 6 always generates linear eddy current damping. When the nonlinear damping unit 4 provides nonlinear damping, the linear damping unit 6 always generates linear eddy current damping, thereby generating nonlinear damping whose damping coefficient increases exponentially with the increase of amplitude. Specifically, the damping coefficient of the damping device is satisfy .

[0122] Figure 9 The stiffness coefficient of the damping device obtained in the specific embodiment changes with the actual horizontal displacement of the single mass block 2 It can be seen that when hour, , the stiffness coefficient is approximately constant, and the stiffness coefficient changes slightly with the displacement amplitude of the single mass block 2. When the displacement amplitude of the single mass block 2 increases, the stiffness coefficient increases nonlinearly. That is, the larger the amplitude of the single mass block 2, the stiffness coefficient increases by several times. Specifically, the damping coefficient of the damping device is satisfy .

[0123] It can be seen that the present invention realizes dual vibration reduction from the perspectives of stiffness and damping adjustment through the combination of the nonlinear damping unit 4 and the stiffness adjustment unit 5 under extreme load, thereby ensuring the damping vibration reduction effect and effectively improving the safety and service life of the overall structure of the controlled structure.

[0124] While the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and equivalent components may be substituted without departing from the scope of the present invention. In particular, the various technical features described in the various embodiments may be combined in any manner, provided no structural conflicts exist. The present invention is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A graded variable damping and variable stiffness pendulum damping device, characterized in that: The invention comprises a damping mounting frame, a single mass block swingably mounted on the damping mounting frame, a plurality of vertical guides passing through the single mass block, a nonlinear damping unit and a stiffness adjustment unit arranged between the single mass block and the vertical guide, and a linear damping unit arranged below the single mass block, wherein the linear damping unit comprises a lower permanent magnet assembly and a lower conductor assembly arranged relative to each other with a constant gap, the lower permanent magnet assembly or the lower conductor assembly being horizontally limited and vertically decoupled from the single mass block by the vertical guide; the nonlinear damping unit generates nonlinear eddy current damping when the single mass block swings to a first critical height, and the linear damping unit always generates linear eddy current damping when the single mass block swings; the stiffness adjustment unit generates nonlinear stiffness when the single mass block swings to a second critical height; A linear damping gap is left between the single mass block and the lower permanent magnet assembly. When the single mass block moves from an initial state to a state where the linear damping gap is zero, the lower permanent magnet assembly and the lower conductor assembly move in parallel to generate linear damping. When the single mass block continues to move upward, the nonlinear damping unit generates nonlinear eddy current damping. The nonlinear damping unit includes an upper permanent magnet group and an upper conductor plate, wherein the upper permanent magnet group is disposed at the upper end portion of the vertical guide member, and the upper conductor plate is disposed in a through hole of the single mass block that penetrates the vertical guide member. When the upper conductor plate moves to the upper permanent magnet group, it cuts the magnetic flux lines to generate eddy currents. The first critical height is the initial distance between the lower end surface of the upper permanent magnet group and the upper end surface of the upper conductor plate. The first critical height is equal to the linear damping gap of the single mass block in the initial state. The sum of the linear damping gap of the single mass block in the initial state and the axial length of the upper permanent magnet group is greater than the vertical limit displacement of the single mass block. The stiffness adjustment unit includes an adjustment spring and a limiting portion that cooperates with the adjustment spring. The adjustment spring is arranged at the upper end portion of the vertical guide member, and the limiting portion is the upper end surface of the single mass block. The second critical height is the initial distance between the lower end surface of the adjustment spring and the upper end surface of the single mass block. When the single mass block swings to the second critical height, the upper end surface of the single mass block contacts the adjustment spring and generates nonlinear stiffness. The sum of the second critical height and the axial length of the adjustment spring is greater than the vertical limit displacement of the single mass block.

2. The step-by-step variable damping and variable stiffness pendulum damping device according to claim 1, characterized in that: The actual horizontal displacement of the single mass block and the damping coefficient of the damping device satisfy the following relationship: in, is the damping coefficient of the damping device, is the optimal damping coefficient of the linear damping unit, The nonlinear damping coefficient generated by cutting the upper permanent magnet group on the upper conductor plate is: is the preset horizontal displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines, is the actual horizontal displacement of the single mass block, is the swing arm length of the single mass block, is the preset vertical displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines, is the preset axial length of the upper permanent magnet group, is the actual vertical displacement of the single mass block.

3. The graded variable damping and variable stiffness pendulum damping device according to claim 1 or 2, characterized in that: The actual horizontal displacement of the single mass block and the stiffness coefficient of the damping device satisfy the following relationship: in, is the stiffness coefficient of the damping device, is the optimal stiffness coefficient of a single mass block, To adjust the spring stiffness coefficient, is the actual horizontal displacement of the single mass block, is the preset horizontal displacement when the upper end surface of the single mass block begins to contact the adjustment spring, is the swing arm length of the single mass block, is the preset vertical displacement when the upper end surface of the single mass begins to contact the adjustment spring, To adjust the preset axial length of the spring, is the actual vertical displacement of the single mass block.

4. The graded variable damping and variable stiffness pendulum damping device according to claim 1 or 2, characterized in that: The nonlinear damping unit and the stiffness adjustment unit are alternately arranged along the periphery of the single mass block; and the second critical height is greater than or equal to the first critical height.

5. The graded variable damping and variable stiffness pendulum damping device according to claim 1 or 2, characterized in that: A multi-directional guide assembly is provided between the lower permanent magnet assembly and the lower conductor assembly to ensure that the gap between the two remains unchanged. The multi-directional guide assembly includes two sets of guide rail components that are cross-arranged and slide relative to each other. The lower permanent magnet assembly is slidably connected to the guide rail component located on the upper part, and the guide rail component located on the lower part is fixedly installed on the lower conductor assembly.

6. A vibration reduction configuration method for the graded variable damping and variable stiffness pendulum damping device according to any one of claims 1 to 5, characterized in that: include: According to the mass of the single mass , modal quality of the target mode of the controlled structure Calculate mass ratio , according to the mass ratio Determine the swing arm length of a single mass block , the optimal damping ratio of the linear damping unit ; Determination of the horizontal limit displacement of a single mass block , according to the swing arm length of the single mass block and the horizontal limit displacement of the single mass block Determine the vertical limit displacement of a single mass block ; According to the optimal damping ratio of the linear damping element Calculate the optimal damping coefficient of the linear damping element , the optimal damping coefficient of the linear damping unit Set as the basic damping coefficient; adjust any one or more of the initial distance between the upper permanent magnet group and the upper conductor plate in the nonlinear damping unit, the axial length of the upper conductor plate, the axial length of the upper permanent magnet group, the number of permanent magnets in the upper permanent magnet group, and the permanent magnet arrangement parameters, so that the nonlinear damping coefficient generated by the upper conductor plate cutting the upper permanent magnet group is adjusted based on the basic damping coefficient ; According to the horizontal limit displacement of the single mass block Configure the preset horizontal displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines , and then determine the preset vertical displacement of the single mass block when the upper conductor plate begins to cut the magnetic flux lines ; According to the horizontal limit displacement of the single mass block Determine the preset horizontal displacement at which the upper part of the single mass begins to contact the adjustment spring , and then determine the preset vertical displacement when the upper end surface of the single mass block begins to contact the adjustment spring .

7. The vibration reduction configuration method according to claim 6, characterized in that: The swing arm length of the single mass block The calculation expression is: in, is the swing arm length of the single mass block, is the vibration frequency of the single mass block, is the acceleration due to gravity, is the frequency of the target mode of the controlled structure, is the ratio between the mass of the single mass block and the modal mass of the target mode of the controlled structure, is the mass of the single mass block, is the modal mass of the target mode of the controlled structure; The damping coefficient of the linear damping unit The calculation expression is: in, is the optimal damping coefficient of the linear damping unit, is the optimal damping ratio of the damping device, is the vibration frequency of the single mass block, is the mass of the single mass block, is the ratio between the mass of the single mass block and the modal mass of the target mode of the controlled structure, The preset coefficient is in the range of (0,1].

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