Lever amplification type eddy current tuned mass damper and installation method and application thereof

Abstract

The invention provides a lever amplification type eddy current tuned mass damper and an installation method and application thereof, and belongs to the technical field of energy dissipation and vibration reduction. The lever amplification type eddy current tuned mass damper comprises a mass block, the top of the mass block is provided with a spherical crown-shaped concave surface, six universal steel ball rollers are evenly arranged at the bottom of the mass block so that the mass block can freely slide on a sliding surface of a sliding support, and a lever penetrates through the mass block and the sliding support through universal bearings. The bottom of the lever is connected with a cycloid conductor plate, the sliding support is fixed on the induction base through four hydraulic rods at the bottom, the permanent magnet back iron is fixed on a concave surface structure of the induction base, and an annular permanent magnet array is fixedly arranged on the permanent magnet back iron; the vertical space can be saved, the starting threshold value is reduced through the lever principle, meanwhile, the magnet utilization rate is high, the field intensity is stable, stability and sensitivity are remarkably improved, and application and popularization are facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of structural energy dissipation and vibration reduction, and particularly relates to a lever-amplified eddy current tuned mass damper and its installation method and application. Background Art

[0002] A tuned mass damper (TMD) is a device used to reduce the vibration of a controlled structure. The basic principle of TMD is to utilize the combination of a mass-spring-damper system to match the natural frequency of the structure. When the controlled structure is subjected to an external excitation, the TMD will generate a vibration opposite to that of the controlled structure, thereby effectively reducing the vibration amplitude of the controlled structure.

[0003] The pendulum length of the traditional pendulum TMD occupies a large vertical space.

[0004] The traditional friction pendulum TMD has a high starting threshold, a low ultimate bearing capacity, and poor sensitivity; taking friction damping as the only source of damping affects the control accuracy and effect of TMD; its strong non-linear characteristics cause significant frequency changes under large swing amplitudes and are prone to detuning behavior.

[0005] The traditional hydraulic oil TMD has poor sensitivity, is prone to oil leakage, and is difficult to adapt to high-temperature and cold environments.

[0006] The traditional eddy current TMD has a high cost, low magnet utilization rate, and large iron loss; there is a lot of magnetic leakage and large magnetic resistance; and it has a low energy consumption density and degraded high-speed working performance. Summary of the Invention

[0007] The purpose of the present invention is to provide a lever-amplified eddy current tuned mass damper and its installation method and application to solve the above problems, saving vertical space; the natural frequency of its cycloidal sliding surface is only related to the radius of the rolling circle and has nothing to do with the swing amplitude, which can effectively avoid its large swing angle detuning behavior; the displacement amplification effect of the lever reduces the starting threshold and improves the control accuracy; completely avoiding the oil leakage problem and having a wide temperature range adaptability; adopting a reduced magnet layout to achieve a high-strength unilateral uniform distribution, with a controllable damping coefficient, high energy consumption efficiency, less iron loss, and good economy; improving the stability and sensitivity of the damper and having good durability. In view of this, it can be applied to the energy dissipation and vibration reduction technical field of industries such as building structures, transportation, and mechanical manufacturing.

[0008] To achieve the above purpose, the technical solution adopted by the present invention to solve this technical problem is:

[0009] The present invention first provides a lever-amplified eddy current tuned mass damper, which includes three major regions: a tuning region, an amplification region, and an induction region;

[0010] Furthermore, the tuning area includes a sliding support. The upper surface of the sliding support is an arc sliding surface, which is a cycloidal concave surface. A mass block is placed at the point with the maximum curvature of the arc sliding surface. The mass block contacts the arc sliding surface through a universal steel ball roller connected to its bottom. A cylindrical channel is provided at the vertical axis of the mass block, and a spherical concave surface is provided at the top. A universal bearing is installed at the center of the bottom of the sliding support. The tuning area adjusts the movement trajectory of the mass block to a cycloid.

[0011] Furthermore, the amplification area includes a lever. The lever passes through the cylindrical channel of the mass block and the universal bearing from top to bottom in sequence. The bottom of the lever is connected to a cycloidal conductor plate. The amplification area amplifies the displacement through the lever.

[0012] Furthermore, the induction area includes the induction base. The four corners of the induction base support the sliding support through four hydraulic rods. The upper part of the induction base has a cycloidal concave surface structure. An annular permanent magnet array is fixed on the cycloidal concave surface structure of the upper part of the induction base. The induction area generates eddy currents by cutting the magnetic induction lines formed by the permanent magnets on the induction base through the conductor plate, thereby generating damping.

[0013] Furthermore, a cylindrical channel is provided at the vertical axis of the mass block, and a spherical concave surface is provided at the top. Six universal steel ball rollers are evenly arranged at the bottom so that the mass block can closely fit the sliding surface when sliding on the sliding support. The mass block is naturally located at the point with the maximum curvature of the sliding surface under the action of gravity, so there is no need to add a reset mechanism and a limiting device.

[0014] Furthermore, the arc sliding surface structure on the upper part of the sliding support, the structure of the cycloidal conductor plate, and the concave surface structure on the upper part of the induction base are all cycloidal concave surface structures. The cycloidal concave surface structure is a concave surface structure formed by rotating a cycloid around the symmetry axis. The cycloid is a geometric curve formed by the movement trajectory of a fixed point on the circumference of a rolling circle when the rolling circle freely rolls along a straight line. The parametric equation of the cycloid is θ ∈ [0, 2π], where a represents the rolling radius, θ represents the cumulative radian value turned by the rolling circle. When the circle rolls one week, θ increases from 0 to 2π. Taking the starting contact point of the rolling circle as the coordinate origin, the straight-line rolling direction as the x-axis, and the vertical direction as the y-axis to establish a rectangular coordinate system. x is the distance moved by the center of the circle minus the lateral offset caused by rotation, and y is the distance moved by the center of the circle minus the vertical offset caused by rotation. After designing the sliding surface as a cycloid, its period and natural frequency are fixed values, both only related to the radius of the rolling circle, which can effectively avoid detuning behavior under the action of large-amplitude excitation.

[0015] Furthermore, the lever passes through the cylindrical channel of the mass block and the universal bearing in sequence from top to bottom and fixes the conductor plate at the bottom end of the lever. The lever rotates in the spherical crown concave structure with the universal bearing as a fulcrum, and its displacement amplification coefficient is γ, which can effectively avoid the jamming phenomenon and retain its displacement amplification effect to the maximum extent, thereby significantly reducing the starting threshold and improving the shock absorption effect under the action of medium and small earthquakes.

[0016] Furthermore, the induction base has a cycloid concave structure, a permanent magnet back iron with an annular slot is fixed on the concave structure, the annular Halbach permanent magnet array is fixed in the slot, and the annular Halbach permanent magnet array is composed of fan-shaped permanent magnets of the same size and two magnetization directions, radial and tangential, arranged in different directions. The interaction between radial and tangential magnetized magnets can achieve mutual cancellation of magnetic fields to generate a unilateral strong magnetic field, and its unilateral sinusoidal wave field strength is 1.4 times that of the traditional single radial or axial array arrangement composed of magnets of the same volume. By increasing the magnetic pole ratio, the damping coefficient can be increased to achieve adjustable damping, and the high magnetic flux density significantly improves energy efficiency, completely avoids oil leakage problems and achieves wide temperature range adaptability.

[0017] Furthermore, the concave structure of the induction base and the conductor plate are both cycloid concave structures, ensuring that the diameter distance between the conductor plate and the permanent magnet is constant when the lever is in a balanced position.

[0018] The present invention also provides a method for installing a lever-amplified eddy current tuned mass damper, which mainly comprises the following steps:

[0019] 1) Assembling the mass block: a cylindrical channel is provided at the vertical axis of the mass block and a spherical crown-shaped concave surface is provided at the top, and six universal steel ball rollers are evenly fixed on the bottom ring of the mass block with bolts; and the assembled mass block is naturally placed at the maximum curvature point of the arc sliding surface of the sliding support.

[0020] 2) Assemble the lever: insert the universal bearing through the center of the maximum curvature point of the cycloid sliding surface of the sliding support, and the lever passes through the cylindrical channel and the universal bearing of the mass block installed in step 1) from top to bottom. The maximum curvature point of the concave structure of the conductor plate is fixed to the bottom end of the lever by bolt connection.

[0021] 3) Assembling the eddy current damping component: the permanent magnet back iron is laid on the cycloid concave structure on the upper part of the induction base, the permanent magnet array is a ring-shaped Halbach permanent magnet array formed by staggered combination of multiple fan-shaped magnet blocks of the same size and different magnetization directions, and the permanent magnet back iron is provided with a ring-shaped slot, and the permanent magnet array is fixed in the slot on the permanent magnet back iron;

[0022] 4) The four hydraulic rods are respectively fixed to the bottom of the sliding support installed in step 1) and the four corners of the upper part of the induction base installed in step 3) by means of bolts. During this process, it is necessary to ensure that the conductor plate is collinear with the vertical axis of the induction base.

[0023] Regarding the application of the above-mentioned lever-amplified eddy current tuned mass damper, the lever-amplified eddy current tuned mass damper is installed at a preset position of the controlled structure. When the controlled structure vibrates (shakes), the mass block slides within the cycloidal sliding surface of the sliding support. The mass block pulls the lever to rotate, causing the conductor plate at the bottom end of the lever to cut the magnetic induction line, so that the magnetic flux passing through the conductor plate changes. According to Faraday's law of electromagnetic induction, an induced electromotive force is generated inside the conductor plate, thereby forming an eddy current. According to Lenz's law, the eddy current will generate a new magnetic field opposite to the original magnetic field, and at the same time generate a damping force that hinders the relative movement between the conductor and the permanent magnet array. The energy conversion is as follows: the mechanical energy of the mass block is converted into the electromagnetic energy of the damper system and then dissipated as the resistive heating effect of the conductor. In addition, the lever has a displacement amplification effect. According to the lever principle, even when the controlled structure is subjected to small and medium vibrations (shakes), a slight rotation of the lever will amplify the displacement, pulling the conductor plate to cut the magnetic induction line to generate a damping force.

[0024] Compared with the prior art, the beneficial effects of the present invention include the following aspects:

[0025] 1. For the lever-amplified eddy current tuned mass damper provided by the present invention, the movement trajectory of the mass block of the traditional pendulum-type or friction pendulum-type tuned mass damper is adjusted to a cycloid through the tuning area. The movement period and natural frequency of the mass block on the cycloid sliding surface are only related to the radius of the rolling circle and have nothing to do with the swing angle amplitude, thus avoiding detuning behavior under large-amplitude excitation; at the same time, it saves vertical space and does not require additional limit and self-resetting devices.

[0026] 2. For the lever-amplified eddy current tuned mass damper provided by the present invention, the displacement is amplified by the lever in the amplification area, and its displacement amplification coefficient is γ, effectively reducing the starting threshold and improving the sensitivity of the damper under medium and small earthquakes.

[0027] 3. The lever-amplified eddy current tuned mass damper provided by the present invention adds eddy current damping on the basis of traditional single friction damping, improving the damping sensitivity and accuracy. At the same time, the adoption of the annular Halbach permanent magnet array magnet group reduces the magnet layout to generate a unilateral sine wave strong magnetic field. The magnetic field intensity on the strong side surface is about 1.4 times that of the traditional array composed of magnets of the same volume. Its high magnetic flux density can significantly improve the energy consumption efficiency. The damping coefficient is adjusted by increasing the pole ratio to achieve adjustable damping. At the same time, the provided unilateral magnetic field can prevent other parts from being exposed to the magnetic field strength, with high magnet utilization rate and small iron loss. Description of the Drawings

[0028] Figure 1 is the isometric view of the present invention;

[0029] Figure 2 is the side view of the present invention;

[0030] Figure 3 is the top view of the present invention;

[0031] Figure 4 is the sectional view of the 1-1 section of the present invention;

[0032] Figure 5 is the schematic diagram of the mass block of the present invention;

[0033] Figure 6 is the schematic diagram of the universal bearing of the present invention;

[0034] Figure 7 is the distribution diagram of the permanent magnet of the present invention;

[0035] Figure 8 is the cycloid trajectory diagram;

[0036] Figure 9 is the schematic diagram of the Halbach permanent magnet distribution of the present invention; Figure 9 In (a), it shows the distribution of permanent magnets in a single row with a pole ratio of 2:1, (b) shows the distribution of permanent magnets in a single row with a pole ratio of 1:1, and (c) shows the distribution of permanent magnets in a double row with a pole ratio of 1:1;

[0037] Description of the reference numerals: 1, mass block; 2, universal steel ball roller; 3, universal bearing; 4, lever; 5, sliding surface; 6, sliding support; 7, conductor plate; 8, permanent magnet back iron; 9, permanent magnet array; 10, induction base; 11, hydraulic rod. Detailed Description of the Invention

[0038] The following clearly and completely describes the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention; obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] As Figures 1-4 shown, in this embodiment, a lever-amplified eddy current tuned mass damper is provided, which includes three major regions: a tuning region, an amplification region, and an induction region;

[0040] In this embodiment, the tuning region includes the sliding support. The upper surface of the sliding support is an arc sliding surface, which is a cycloidal concave surface. A mass block is placed at the point with the maximum curvature of the arc sliding surface. A cylindrical channel is provided at the vertical axis of the mass block, and a spherical crown concave surface is provided at the top. Six universal steel ball rollers are evenly arranged at the bottom. A universal bearing is installed at the center of the bottom of the sliding support, which can effectively avoid jamming during the rotation process;

[0041] In this embodiment, the amplification region includes a lever. The lever passes through the cylindrical channel of the mass block and the universal bearing from top to bottom. A conductor plate is fixed at the bottom end of the lever. The lever rotates freely with the universal bearing as the fulcrum to achieve the displacement amplification effect and improve the sensitivity under medium and small earthquakes;

[0042] In this embodiment, the induction region includes the induction base. The four corners of the induction base support the sliding support through four hydraulic rods. A permanent magnet back iron is fixed on the cycloidal concave surface structure of the induction base. An annular slot is provided on the permanent magnet back iron, and an annular permanent magnet array is fixed in the annular slot of the permanent magnet back iron. The radial distance between the conductor plate and the permanent magnet back iron is constant in the equilibrium state.

[0043] As Figure 5 shown, in this embodiment, a cylindrical channel is provided at the vertical axis of the mass block, and a spherical crown concave surface is provided at the top. Six universal steel ball rollers are evenly arranged at the bottom (as Figure 7 shown) so that the mass block can be closely attached to the sliding surface when sliding on the sliding support, and at the same time, the sliding friction is changed to rolling friction to improve the sensitivity of operation.

[0044] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The sliding surface of the sliding support is a cycloidal sliding surface, which is formed by rotating the cycloid equation around the axis of symmetry. The cycloid is a geometric curve formed by the movement trajectory of a fixed point on the circumference of a rolling circle rolling freely along a straight line. The formation process is as Figure 8As shown. The parametric equation of the cycloid θ ∈ [0, 2π], where a represents the rolling radius, θ represents the cumulative radian value rotated by the rolling circle. When the circle rolls one week, θ increases from 0 to 2π. Taking the starting contact point of the rolling circle as the coordinate origin, the straight-line rolling direction as the x-axis, and the vertical direction as the y-axis to establish a rectangular coordinate system. x is the distance that the center of the circle moves minus the lateral offset generated by rotation, and y is the distance that the center of the circle moves minus the vertical offset generated by rotation. After designing the sliding surface as a cycloid type, its period and natural frequency are a fixed value, both only related to the radius of the rolling circle, which can effectively avoid the detuning behavior under the action of large-amplitude excitation;

[0045] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The mass block naturally locates at the point with the maximum curvature of the sliding surface under the action of gravity, so that no reset mechanism and limiting device need to be added to the mass block under the action of excitation.

[0046] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The conductor plate will not touch the bottom of the sliding support and the hydraulic rod under the action of excitation due to the limiting effect of the sliding surface.

[0047] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The lever rotates with the universal bearing as the fulcrum in the spherical crown concave surface structure, which can effectively avoid the jamming phenomenon; According to the lever principle, the lever has a displacement amplification effect, and its displacement amplification coefficient is γ, which can effectively reduce the starting threshold of the TMD and improve the sensitivity under medium and small earthquake actions.

[0048] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The induction base has a cycloid concave surface structure, which is formed by rotating the cycloid equation around the axis of symmetry for one week. A permanent magnet back iron with a ring-shaped slot is fixed on the concave surface structure, and the permanent magnet array is fixed in the ring-shaped slot. The permanent magnet array is a ring-shaped Halbach permanent magnet array formed by staggered combination of sector-shaped permanent magnets with the same size and different magnetization directions, specifically as Figure 9As shown, the annular Halbach permanent magnet array is composed of fan-shaped permanent magnets with the same size but different magnetization directions in the radial and tangential directions arranged in an alternating manner. The magnetic circuit can be optimized by changing the number of arranged rings or the pole ratio. Each cycle in the annular Halbach permanent magnet array is called a pole. The radial direction is defined as the main pole, and the tangential direction is defined as the secondary pole. The pole ratio is the ratio of the central angles corresponding to the main pole and the secondary pole within each pole. The damping coefficient increases with the increase of the pole ratio. The annular Halbach permanent magnet array can achieve the mutual cancellation of magnetic fields through the interaction of radially and tangentially magnetized magnets, thereby generating a high-strength unilateral magnetic field. The unilateral sine wave field strength is 1.4 times that of a traditional array composed of magnets of the same volume. Its high magnetic flux density can significantly improve the energy consumption efficiency. The damping can be adjusted by increasing the pole ratio to increase the damping coefficient. At the same time, the provided unilateral magnetic field can prevent other parts from being exposed to the field strength, with high magnet utilization rate and small iron loss.

[0049] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The concave structure of the induction base and the conductor plate are both cycloidal concave structures, ensuring that the conductor plate is collinear with the vertical axis of the induction base at the equilibrium position.

[0050] In this embodiment, a lever-amplified eddy current tuned mass damper is provided. The radial distance between the conductor plate and the permanent magnet and the pole ratio in the Halbach permanent magnet array are adjusted by the lifting hydraulic rod, thereby changing the magnitude of the eddy current damping.

[0051] The installation method of the above-mentioned lever-amplified eddy current tuned mass damper includes the following steps:

[0052] 1) Assemble the mass block: A cylindrical channel is provided at the vertical axis of the mass block 1, and a spherical concave surface is provided at the top. Six universal steel ball rollers 2 are evenly fixed to the bottom ring of the mass block 1 with bolts; and the assembled mass block 1 is naturally placed at the position with the maximum curvature of the arc sliding surface 5 of the sliding support 6.

[0053] 2) Assemble the lever: The universal bearing 3 is inserted through the center of the point with the maximum curvature of the cycloidal sliding surface 5 of the sliding support 6. The lever 4 passes through the cylindrical channel of the mass block 1 and the universal bearing 3 installed in step 1) from top to bottom in sequence. The point with the maximum curvature of the concave structure of the conductor plate 7 is fixed to the bottom end of the lever by means of bolt connection.

[0054] 3) Assemble the eddy current damping components: The permanent magnet back iron 8 is laid on the cycloidal concave structure on the upper part of the induction base 10. The permanent magnet array 9 is composed of a plurality of magnet blocks with the same shape but different magnetization directions staggered and combined into an annular Halbach permanent magnet array. The permanent magnet back iron 8 is provided with an annular slot, and the permanent magnet array 9 is fixed in the slot on the permanent magnet back iron 8.

[0055] 4) The four hydraulic rods 11 are respectively fixed to the bottom of the sliding support 6 installed in step 1) and the upper four corners of the induction base 10 installed in step 3) by means of bolts. During this process, it is necessary to ensure that the conductor plate 7 is collinear with the vertical axis of the induction base 10.

[0056] The lever-amplified eddy current tuned mass damper of the present invention is installed at a preset position of the controlled structure. When the controlled structure vibrates, the mass block 1 slides within the cycloidal sliding surface 5 of the sliding support 6. The mass block 1 pulls the lever 4 to rotate, causing the conductor plate 7 at the bottom of the lever 4 to cut the magnetic induction line, so that the magnetic flux passing through the conductor plate 7 changes. According to Faraday's law of electromagnetic induction, an induced electromotive force is generated inside the conductor plate 7, thus forming an eddy current. According to Lenz's law, the eddy current will generate a new magnetic field opposite to the original magnetic field, and at the same time generate a damping force that hinders the relative movement of the conductor 7 and the permanent magnet array 9. The energy conversion is as follows: the mechanical energy of the mass block 1 is converted into the electromagnetic energy of the damper system and then dissipated as the resistive heating effect of the conductor. In addition, the lever 4 has a displacement amplification effect. According to the lever principle, even when the controlled structure is subjected to small and medium vibrations, a slight rotation of the lever 4 will also amplify the displacement, pulling the conductor plate 7 to cut the magnetic induction line to generate a damping force.

[0057] As mentioned above, it is only the preferred specific embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any technical staff familiar with the technical field, within the scope of the technology disclosed in the invention, making non-substantive changes to the present invention using this concept shall fall within the scope of infringement of the protection of the present invention.

Claims

1. The lever-amplified eddy current tuned mass damper is characterized in that, The lever-amplified eddy current tuned mass damper includes three major regions: a tuning region, an amplification region, and an induction region; The tuning region includes a sliding support (6). The upper surface of the sliding support (6) is an arc sliding surface (5), which is a cycloidal concave surface. A mass block (1) is placed at the position with the maximum curvature of the arc sliding surface (5). The mass block contacts the arc sliding surface (5) through a universal steel ball roller (2) connected to its bottom. A cylindrical channel is provided at the vertical axis of the mass block (1) and a spherical crown concave surface is provided at the top. A universal bearing (3) is installed at the center of the bottom of the sliding support (6). The tuning region adjusts the movement trajectory of the mass block to a cycloid; The amplification region includes a lever (4). The lever passes through the cylindrical channel of the mass block (1) and the universal bearing (3) from top to bottom in sequence. The bottom of the lever (4) is connected to a cycloidal conductor plate (7). The amplification region amplifies the displacement through the lever; The induction region includes the induction base (10). The four corners of the induction base (10) support the sliding support (6) through four hydraulic rods (11). The upper part of the induction base has a cycloidal concave surface structure. An annular permanent magnet array (9) is fixed on the cycloidal concave surface structure of the upper part of the induction base. The induction region generates eddy currents by cutting the magnetic induction lines formed by the permanent magnets on the induction base through the conductor plate (7), thereby generating damping.

2. The lever-amplified eddy current tuned mass damper according to claim 1, wherein The arc sliding surface (5) structure on the upper part of the sliding support (6), the structure of the cycloid conductor plate (7), and the concave surface structure on the upper part of the induction base (10) are all cycloid concave surface structures. The cycloid concave surface structure is a concave surface structure formed by rotating a cycloid around its axis of symmetry. A cycloid is a geometric curve formed by the locus of a fixed point on the circumference of a rolling circle as it rolls freely along a straight line. The parametric equation of the cycloid is where a represents the rolling radius, θ represents the cumulative radian value by which the rolling circle has turned. When the circle rolls one full turn, θ increases from 0 to 2π. Taking the starting contact point of the rolling circle as the origin of the coordinate system, with the straight-line rolling direction as the x-axis and the vertical direction as the y-axis to establish a rectangular coordinate system, x is the distance the center of the circle has moved minus the lateral offset caused by rotation, and y is the distance the center of the circle has moved minus the vertical offset caused by rotation.

3. The lever-amplified eddy current tuned mass damper according to claim 2, wherein Six universal steel ball rollers (2) are provided and evenly arranged on the outer edge of the bottom of the mass block (1). The mass block (1) is naturally located at the position with the maximum curvature of the arc sliding surface (5) of the sliding support (6).

4. The lever-amplified eddy current tuned mass damper according to claim 1 or 2 or 3, characterized in that, A permanent magnet back iron (8) with an annular slot is laid on the cycloidal concave surface structure of the upper part of the induction base (10). The annular Halbach permanent magnet array (9) is fixed on the permanent magnet back iron (8). The annular Halbach permanent magnet array is composed of a way of arranging fan-shaped permanent magnets with the same size in two magnetization directions, radial and tangential, in an alternating direction. Each cycle in the annular Halbach permanent magnet array is called a pole. The radial direction is defined as the main pole and the tangential direction is defined as the secondary pole. The pole ratio is the ratio of the central angles corresponding to the main pole and the secondary pole within each pole. The damping coefficient increases with the increase of the pole ratio.

5. The lever-amplified eddy current tuned mass damper according to claim 4, wherein The conductor plate (7) is collinear with the vertical axis of the induction base (10).

6. The installation method of the lever-amplified eddy current tuned mass damper according to any one of claims 1-5, the method comprising the following steps: 1) Assemble the mass block: A cylindrical channel is provided at the vertical axis of the mass block (1) and a spherical crown concave surface is provided at the top. Six universal steel ball rollers (2) are evenly fixed on the bottom ring of the mass block (1) with bolts; and the assembled mass block (1) is naturally placed at the position with the maximum curvature of the arc sliding surface (5) of the sliding support (6); 2) Assemble the lever: Pass the universal bearing (3) through the center of the point with the maximum curvature of the cycloidal sliding surface (5) of the sliding support (6). The lever (4) passes through the cylindrical channel of the mass block (1) and the universal bearing (3) installed in step 1) from top to bottom. The concave structure of the conductor plate (7) is fixed at the bottom end of the lever by means of bolt connection at the point with the maximum curvature; 3) Assemble the eddy current damping component: Lay the permanent magnet back iron (8) on the cycloidal concave structure on the upper part of the induction base (10). The permanent magnet array (9) is formed by staggered combination of multiple sector magnet blocks of the same size but different magnetization directions into an annular Halbach permanent magnet array. The permanent magnet back iron (8) is provided with an annular slot, and the permanent magnet array (9) is fixed in the slot on the permanent magnet back iron (8); 4) Fix the top and bottom ends of the four hydraulic rods (11) to the bottom of the sliding support (6) installed in step 1) and the four corners of the upper part of the induction base (10) installed in step 3) by means of bolt connection. During this process, it is necessary to ensure that the vertical axes of the conductor plate (7) and the induction base (10) are collinear.

7. Application of the lever-amplified eddy current tuned mass damper as claimed in claims 1-5. The lever-amplified eddy current tuned mass damper is installed at a preset position of the controlled structure. When the controlled structure vibrates (shakes), the mass block (1) slides within the cycloidal sliding surface (5) of the sliding support (6). The mass block (1) pulls the lever (4) to rotate, causing the conductor plate (7) at the bottom end of the lever (4) to cut the magnetic induction lines of force, so that the magnetic flux passing through the conductor plate (7) changes. According to Faraday's law of electromagnetic induction, an induced electromotive force is generated inside the conductor plate (7), thereby forming an eddy current. According to Lenz's law, the eddy current will generate a new magnetic field opposite to the original magnetic field, and at the same time generate a damping force that hinders the relative movement between the conductor (7) and the permanent magnet array (9). The energy conversion is as follows: the mechanical energy of the mass block (1) is converted into the electromagnetic energy of the damper system and then dissipated as the resistive heat effect of the conductor. In addition, the lever (4) has a displacement amplification effect. According to the lever principle, even when the controlled structure is subjected to small and medium vibrations (shakes), a slight rotation of the lever (4) will also amplify the displacement, pulling the conductor plate (7) to cut the magnetic induction lines of force to generate a damping force.

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