Power transmission tower steel pipe vibration damping method and damping damper

Abstract

The application discloses a power transmission tower steel pipe vibration damping method and a damper, and the method steps comprise the following steps: constructing an equivalent one-dimensional linear magnetic circuit model of the eddy current damper, wherein the equivalent one-dimensional linear magnetic circuit model is composed of series connection of air gap reluctance, magnetic conductive tube reluctance, permanent magnet reluctance and magnetic motive force provided by the permanent magnet; constructing an eddy current damping force calculation model, wherein the eddy current damping force calculation model is a relationship model between air gap magnetic flux density and the eddy current damping force and a relationship model between the damping coefficient and the eddy current damping force; continuously adjusting configuration values of geometric parameters and material attribute parameters of the permanent magnet, the air gap and the magnetic conductive tube, and calculating corresponding damping coefficients until the optimal damping coefficient is obtained; configuring the eddy current damper according to the optimal configuration values of the parameters corresponding to the optimal damping coefficient, and setting the damper on a power transmission tower steel pipe structural member to realize vibration damping. The application has the advantages of simple implementation method, low cost, convenient application and good vibration damping effect.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction technology, specifically to a vibration reduction method and a vibration damper for transmission tower steel pipes. Background Technology

[0002] Steel pipe structures possess excellent shape, low windward coefficient, large radius of gyration, and are lightweight yet high-strength, exhibiting good isotropy. Their structural calculations simplify stress distribution and clarify stress paths, effectively reducing wind loads on the tower and improving structural stability. Therefore, they are widely used in most transmission line towers. Steel pipe tower structures are composed of numerous interconnected steel pipe components. Continuous and repetitive vibrations in these components can lead to fatigue failure, affecting the safety of the entire transmission line and its surrounding area. Therefore, researching methods to prevent vibration phenomena in steel pipe tower members and safeguard structural health has significant engineering practical value. Wind load is the primary design load for transmission steel pipe towers. Wind loads can cause vortex-induced vibrations in localized steel pipe members, resulting in localized damage within the area where the node plate and steel pipe intersect or are adjacent to each other. Over time, this can lead to fatigue failure, affecting the safety of the main structure of the steel pipe tower.

[0003] Eddy current dampers directly convert mechanical energy into heat energy through electromagnetic induction, effectively suppressing vibrations and achieving vibration reduction. Their application in transmission tower steel pipes enables non-contact, highly reliable vibration control. However, the vibration reduction performance of eddy current dampers depends heavily on parameter design, especially the damping coefficient, which directly determines the damping effect and applicability. Determining the damping coefficient is the primary task in designing eddy current dampers, as different damping coefficients directly impact the vibration reduction effect. The damping coefficient of an eddy current damper is related to various parameters, such as the magnetic flux density of the permanent magnet, the air gap size, the conductivity, and the conductor thickness. Furthermore, the permanent magnets in eddy current dampers have a complex three-dimensional, interlaced circular distribution, making magnetic field analysis extremely difficult and hindering the direct determination of the optimal damping coefficient. In existing technologies, finite element software is typically used to directly calculate the parameters of the damper. This method is complex, time-consuming, and not conducive to initial parameter design and parameter optimization. In practice, it is still difficult to accurately determine the optimal damping coefficient in the initial design stage of the eddy current damper. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a vibration reduction method and damping device for transmission tower steel pipes that is simple to implement, low in cost, easy to apply and has good vibration reduction effect.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0006] A method for vibration reduction of steel pipes in transmission towers, comprising the following steps:

[0007] Construct an equivalent one-dimensional linear magnetic circuit model of an eddy current damper, wherein the equivalent one-dimensional linear magnetic circuit model is composed of an air gap magnetoresistive element. Magnetic resistance of conductor tube Permanent magnet reluctance and the magnetomotive force provided by the permanent magnet It is composed of series connection, which consists of air gap magnetoresistive Magnetic resistance of conductor tube Permanent magnet reluctance Magnetic resistance The magnetomotive force The total magnetic reluctance is calculated based on the geometric parameters and material properties of the permanent magnet. It is calculated based on the geometric parameters of the permanent magnet, air gap, and conductor tube;

[0008] A calculation model for eddy current damping force is constructed, wherein the calculation model for eddy current damping force is based on the air gap magnetic flux density. With eddy current damping force Relationship model and damping coefficient With eddy current damping force The relationship model between the air gap magnetic flux density According to the magnetomotive force and the total magnetic resistance Calculated;

[0009] The configuration values ​​of the geometric parameters and material properties of the permanent magnet, air gap, and conductor tube are continuously adjusted, and the corresponding damping coefficient is calculated according to the eddy current damping force calculation model. Continue until the optimal damping coefficient is obtained;

[0010] The eddy current damper is configured according to the optimal configuration values ​​of the geometric parameters and material properties of the permanent magnet, air gap, and conductor tube corresponding to the optimal damping coefficient, and the configured eddy current damper is installed on the steel pipe structure of the transmission tower to achieve vibration reduction.

[0011] Furthermore, based on the characteristic that the permanent magnets in the eddy current damper are periodically and alternately distributed in the circumferential direction, the problem of the three-dimensional circumferentially distributed magnetic field is simplified into a two-dimensional planar model containing rectangular cross-sectional elements of magnetic pole pairs. Half of the adjacent magnetic poles are taken as the analysis unit, and the two-dimensional planar model is abstracted into a one-dimensional linear model to construct the equivalent one-dimensional linear magnetic circuit model.

[0012] Furthermore, the magnetomotive force The calculation expression is:

[0013] ,

[0014] in, The residual magnetic flux density of the permanent magnet. The thickness of the permanent magnet. The vacuum permeability;

[0015] The total magnetic reluctance The calculation expression is:

[0016] ,

[0017] in, The relative permeability of the permanent magnet. The thickness of the air gap. The thickness of the conductor tube, The cross-sectional area of ​​the permanent magnet, air gap, and conductor tube;

[0018] The air gap magnetic flux density The calculation expression is:

[0019] ,

[0020] in, denoted as , where is the magnetic flux of the magnetic circuit.

[0021] Furthermore, the geometric parameters include the cross-sectional area of ​​the permanent magnet, the thickness of the permanent magnet, the thickness of the air gap, and the thickness of the conductor tube; the material property parameters include the remanent magnetic flux density of the permanent magnet, the relative permeability of the magnet, and the conductor conductivity of the conductor tube; and the calculation expression for the eddy current damping force calculation model is as follows:

[0022] ,

[0023] in, The cross-sectional area of ​​the permanent magnet is... The number of magnetic pole pairs, The conductivity of a conductor. The residual magnetic flux density of a permanent magnet The air gap magnetic flux density is... The relative velocity between the permanent magnet and the conductor tube. The thickness of the air gap. The thickness of the conductor tube, The relative permeability of the permanent magnet. The damping coefficient is... This is the eddy current damping force.

[0024] Furthermore, the configuration values ​​of the geometric parameters and material properties of the permanent magnet, air gap, and conductor tube are continuously adjusted, and the corresponding damping coefficient is calculated according to the eddy current damping force calculation model. Until the optimal configuration values ​​for each parameter are obtained, including:

[0025] Determine the target damping coefficient Scope;

[0026] The number of magnetic pole pairs is determined based on the installation space of the eddy current damper. and permanent magnet cross-sectional area The upper limit;

[0027] The initial configuration values ​​of the geometric parameters, material properties, and number of pole pairs p of the permanent magnet, air gap, and conductor tube in a target eddy current damper are selected as the starting point for iteration. The geometric parameters include the cross-sectional area of ​​the permanent magnet, the thickness of the permanent magnet, the thickness of the air gap, and the thickness of the conductor tube. The material properties include the remanent magnetic flux density of the permanent magnet, the relative permeability of the magnet, and the conductor conductivity of the conductor tube.

[0028] Input the configured values ​​of each parameter into the constructed eddy current damping force calculation model to calculate the corresponding damping coefficient. ;

[0029] Determine the currently calculated damping coefficient Does it meet the preset requirements?

[0030] If the calculated damping coefficient Meeting the preset requirements yields the optimal damping coefficient, as well as the corresponding geometric parameters, material properties, and number of pole pairs for the permanent magnet, air gap, and conductor tube. Output the optimal configuration value;

[0031] If the calculated damping coefficient If the preset requirements are not met, adjust the geometric parameters, material properties, and number of pole pairs of the permanent magnet, air gap, and conductor tube. Any one or more configuration values ​​from the configuration values ​​are re-entered into the eddy current damping force calculation model for iterative calculation.

[0032] Furthermore, it also includes configuring the thickness of the permanent magnet according to the following rules. Thickness of the permanent magnet The initial value is continuously increased, and the following condition is met: ,in The thickness of the conductor tube, The thickness of the permanent magnet. A preset coefficient greater than 1 is used when the thickness of the permanent magnet is increased. The corresponding damping coefficient The optimal thickness of the permanent magnet is determined when the increase is less than a preset ratio. The thickness of the conductor tube according to Calculations show that The thickness of the air gap.

[0033] A vibration damper for transmission tower steel pipes using the method described above includes a cylindrical assembly and a connecting assembly for connecting to the steel pipe. The connecting assembly is connected to one end of the cylindrical assembly. A permanent magnet is provided inside the cylindrical assembly. Mass blocks are provided on both sides of the permanent magnet. An elastic element is abutted between the mass blocks and the end of the cylindrical assembly. The cylindrical assembly includes a conductor tube that cooperates with the permanent magnet. An air gap is formed by the air gap between the mass blocks and the conductor tube.

[0034] As a further improvement to the above technical solution:

[0035] The cylindrical assembly consists of two sets: a vertical damping cylinder assembly arranged along the height of the transmission tower, and a horizontal damping cylinder assembly arranged intersecting the vertical damping cylinder assembly. The vertical damping cylinder assembly and the horizontal damping cylinder assembly are connected to each other by guide sliding members and move along their respective arrangement directions.

[0036] The vertical damping cylinder assembly and the horizontal damping cylinder assembly are arranged orthogonally. The guide sliding member is a guide sliding plate. The two end faces of the guide sliding plate are respectively provided with a vertical mating part that slides with the vertical damping cylinder assembly and a horizontal mating part that slides with the horizontal damping cylinder assembly.

[0037] The permanent magnet is a ring-shaped permanent magnet, and the mass blocks on both sides are connected by threaded fasteners, which pass through the middle of the ring-shaped permanent magnet. The mass block has an annular protrusion on the side away from the permanent magnet, and a flexible anti-collision block is provided in the annular protrusion.

[0038] Compared with the prior art, the advantages of the present invention are as follows:

[0039] 1. The method of this invention utilizes the characteristic of the periodic staggered distribution of permanent magnets in the circumferential direction of the eddy current damper to construct an equivalent one-dimensional linear magnetic circuit model of the eddy current damper for quantitative calculation of the magnetic circuit. Simultaneously, it constructs an eddy current damping force calculation model, establishes the correspondence between the geometric parameters and material properties of the permanent magnets, air gap, and conductor tube in the eddy current damper and the damping coefficient, and determines the optimal configuration value of each parameter by adjusting the geometric parameters and material properties of the permanent magnets, air gap, and conductor tube in the eddy current damper until the optimal damping coefficient is reached. Then, the optimal configuration value of each parameter is determined, and the eddy current damper is configured according to the determined optimal configuration value. Applying this eddy current damper to the steel pipe of the transmission tower can effectively prevent the vibration of the steel pipe tower members and achieve the best vibration reduction effect, effectively suppressing wind-induced vibration and ensuring safe and stable operation under actual wind speeds.

[0040] 2. This invention's vibration damper is based on the principle of eddy currents and features an overall cylindrical structure, making it easy to install. Its volume is significantly smaller than existing plate array dampers, avoiding limitations imposed by installation space and conditions. It is also lighter, minimizing its impact on steel pipe loads. Furthermore, the elastic element, permanent magnet, and mass block are all easily adjustable. This allows for adjustments to be made for different steel pipe vibration frequencies, specifically suppressing the vibration of each individual pipe without affecting the overall or local structure of the steel pipe tower. Additionally, it can resonate with the steel pipe structure to be damped, resulting in better vibration reduction performance. The modular replacement design further facilitates handling different specific steel pipe vibration situations, effectively preventing steel pipe vibration. Attached Figure Description

[0041] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0042] Figure 1 This is a schematic diagram illustrating the implementation process of the vibration reduction method for transmission tower steel pipes according to the present invention.

[0043] Figure 2 This is a schematic diagram illustrating the principle of the periodic unit and magnetic flux flow direction constructed in this embodiment.

[0044] Figure 3 This is a schematic diagram of the principle of the magnetic flux equivalent one-dimensional linear magnetic circuit model constructed in this embodiment.

[0045] Figure 4 This is a schematic diagram of the simplified mathematical model of an eddy current damper.

[0046] Figure 5 This is a schematic diagram of the structure of the transmission tower steel pipe vibration damper of the present invention in a specific application.

[0047] Figure 6 This is a three-dimensional structural schematic diagram of the vibration reduction and damping of the steel pipe of the transmission tower according to the present invention.

[0048] Figure 7 This is a three-dimensional structural schematic diagram of the vertical damping cylinder assembly of the present invention.

[0049] Figure 8 This is a front view of the vertical damping cylinder assembly of the present invention.

[0050] Figure 9 yes Figure 8 A sectional view of section AA.

[0051] Figure 10 This is a three-dimensional structural diagram of the transverse damping cylinder assembly of the present invention.

[0052] Figure 11 This is a three-dimensional structural diagram of the guide sliding plate of the present invention.

[0053] Figure 12 This is a comparison curve of the vibration damping response of the present invention and that of the untreated vortex-induced vibration in the vortex vibration range.

[0054] The labels in the diagram represent:

[0055] 1. Cylinder assembly; 11. Conductor tube; 12. Guide cylinder; 13. Protective cylinder; 14. End cap; 15. Sealing element; 16. Vertical damping cylinder assembly; 161. Vertical guide rail; 17. Transverse damping cylinder assembly; 171. Transverse guide rail; 2. Connecting assembly; 3. Permanent magnet; 4. Mass block; 41. Threaded fastener; 42. Annular protrusion; 43. Flexible anti-collision block; 5. Elastic element; 6. Guide sliding part; 61. Vertical mating part; 62. Transverse mating part; 7. Transmission tower; 8. Air gap. Detailed Implementation

[0056] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, but this does not limit the scope of protection of the present invention.

[0057] like Figure 1 As shown, the steps of the vibration reduction method for transmission tower steel pipes in this embodiment include:

[0058] Step S01. Construct an equivalent one-dimensional linear magnetic circuit model of the eddy current damper, wherein the equivalent one-dimensional linear magnetic circuit model is composed of an air gap magnetoresistive... Magnetic resistance of conductor tube Permanent magnet reluctance and the magnetomotive force provided by permanent magnet 3 It is composed of series connection, which consists of air gap magnetoresistive Magnetic resistance of conductor tube Permanent magnet reluctance The series connection constitutes the total magnetic reluctance magnetomotive force The total magnetic reluctance was calculated based on the geometric parameters and material properties of permanent magnet 3. The results were calculated based on the geometric parameters of permanent magnet 3, air gap 8, and conductor tube.

[0059] Step S02. Construct a calculation model for eddy current damping force, which is based on the air gap magnetic flux density. With eddy current damping force Relationship model and damping coefficient With eddy current damping force Relationship model between air gap magnetic flux density According to magnetomotive force and total magnetic reluctance Calculated;

[0060] Step S03. Continuously adjust the configuration values ​​of the geometric parameters and material property parameters of the permanent magnet 3, air gap 8, and conductor tube, and calculate the corresponding damping coefficient according to the eddy current damping force calculation model. Continue until the optimal damping coefficient is obtained;

[0061] Step S04. Configure the eddy current damper according to the optimal configuration values ​​of the geometric parameters and material property parameters of the permanent magnet 3, air gap 8, and conductor tube corresponding to the optimal damping coefficient, and set the configured eddy current damper on the steel pipe structure of the transmission tower 7 to achieve vibration reduction.

[0062] This embodiment draws an analogy between resistance and current in a circuit and magnetic field theory. Utilizing the periodic, staggered distribution of permanent magnets 3 in the circumferential direction within the eddy current damper, an equivalent one-dimensional linear magnetic circuit model of the eddy current damper is constructed to quantitatively calculate the magnetic circuit. Simultaneously, an eddy current damping force calculation model is established, defining the geometric parameters, material properties, and damping coefficients of the permanent magnets 3, air gap 8, and conductor tube within the eddy current damper. The correspondence between them can be determined by adjusting the geometric parameters and material properties of the permanent magnet 3, air gap 8, and conductor tube in the eddy current damper until the optimal damping coefficient is reached. The optimal configuration value of each parameter can then be determined. The eddy current damper can then be configured according to the determined optimal configuration value of each parameter. When the eddy current damper is applied to the steel pipe of the transmission tower 7, it can effectively prevent the vibration of the steel pipe tower members and achieve the best vibration reduction effect. It can also effectively suppress wind-induced vibration and ensure safe and stable operation under actual wind speed.

[0063] In this embodiment, step S01 is specifically based on the characteristic that the permanent magnets 3 in the eddy current damper are periodically and alternately distributed in the circumferential direction. The problem of the three-dimensional circumferentially distributed magnetic field is simplified into a two-dimensional planar model containing rectangular cross-sectional units of magnetic pole pairs. Half of the adjacent magnetic poles are taken as the analysis unit, and the two-dimensional planar model is abstracted into a one-dimensional linear model to form an equivalent one-dimensional linear magnetic circuit model.

[0064] Specifically, this embodiment simplifies the complex three-dimensional magnetic field analysis into an equivalent one-dimensional linear magnetic circuit model through two steps:

[0065] First, by utilizing the periodicity of the magnetic pole arrangement, a complete circular structure can be cut and unfolded, transforming the three-dimensional rotation problem into a two-dimensional planar static model (i.e., a rectangular cross-sectional element containing typical N and S pole pairs), which can significantly reduce the dimensionality of the analysis.

[0066] Furthermore, based on the key characteristics of the main magnetic flux path, the two-dimensional field is further abstracted into a one-dimensional linear magnetic circuit model, which is an equivalent circuit composed of a magnetomotive force source and series / parallel magnetic reluctance. Thus, Kirchhoff's laws of magnetic circuits can be used for simple analytical calculations, achieving a perfect balance between accuracy and efficiency.

[0067] This embodiment cleverly utilizes the periodicity of the circumferential distribution of permanent magnets 3 to expand and represent the circumferentially staggered permanent magnets 3 through the periodic assumption. By "taking half a period and expanding radially," a complex three-dimensional circumferential problem can be effectively simplified into a two-dimensional planar problem, and further simplified into a one-dimensional linear magnetic circuit model. By solving this magnetic circuit model, the total magnetic reluctance can be easily and quantitatively calculated based on the geometric parameters and material properties of the permanent magnets 3, the air gap 8, and the conductor tube. and magnetomotive force This makes it easier to perform initial design and parameter optimization of eddy current dampers.

[0068] In a specific application embodiment, the detailed steps for constructing the equivalent one-dimensional linear magnetic circuit model of the eddy current damper are as follows: When there are materials with high magnetic permeability (such as ferromagnetic materials) or magnetic objects (such as permanent magnets 3) in the magnetic field, the magnetic field distribution will be significantly affected. That is, the trend and distribution of magnetic field lines can be roughly determined by the arrangement of ferromagnetic materials and magnetic objects.

[0069] A magnetic circuit is defined as a closed loop formed by magnetic flux. The laws of magnetic circuits can be expressed as:

[0070] (1)

[0071] In the formula, Represents the magnetic flux of a magnetic circuit. This represents the magnetomotive force, used to describe the ability of a permanent magnet 3 to generate magnetic flux. Indicates magnetic reluctance.

[0072] Similar to electric potential, magnetomotive force is defined as the integral of the magnetic field strength along the path:

[0073] (2)

[0074] In the formula, denoted as , where is the magnetic field strength.

[0075] Magnetic resistance Defined as:

[0076] (3)

[0077] In the formula, For length, Permeability, Cross-sectional area. As can be seen from equation (3), the magnetic reluctance is directly proportional to the length of the material and inversely proportional to the permeability. The longer, thinner, and lower the permeability of the material, the greater the corresponding magnetic reluctance.

[0078] This embodiment draws an analogy between the relationships of magnetic flux, magnetomotive force, and magnetic reluctance in a magnetic circuit and the relationships of current, voltage, and resistance in Ohm's law for electrical circuits; that is, the magnetic circuit also obeys similar laws to those for electrical circuits. If we consider the magnetic reluctance... , ...connected in series, the total magnetic reluctance It obeys Kirchhoff's first law of magnetic circuits, namely:

[0079] (4)

[0080] Furthermore, every node in the magnetic circuit obeys Kirchhoff's second law of magnetic flux, meaning the sum of the magnetic fluxes is zero, expressed as:

[0081] (5)

[0082] Considering that the permanent magnets 3 in the eddy current damper are periodically and alternately distributed along the circumference, for ease of analysis, this embodiment unfolds them radially and takes half of the cycle for magnetic circuit calculation. For example... Figure 2 As shown, half of the adjacent magnetic poles are taken as the analysis unit, forming a structure as follows: Figure 3 The magnetic circuit shown in the diagram has arrows indicating the direction of magnetic flux flow. Then, from... Figure 3 It can be seen that the magnetic circuit passes through two permanent magnets 3, two air gaps 8, two conductor tubes 11, one permanent magnet frame, and one magnetic conductor tube. The cross-sectional areas of the permanent magnets 3, air gaps 8, and conductor tubes 11 can be approximated as half the projected area of ​​a complete permanent magnet 3. Assume the thickness of permanent magnet 3 is... The residual magnetic flux density is Then the magnetomotive force that permanent magnet 3 can provide is:

[0083] (6)

[0084] In the formula, is the vacuum permeability.

[0085] Since the conductor tube 11 and the permanent magnet frame are made of ferromagnetic materials with very high permeability, their magnetic reluctance can be ignored. Assume the thickness of the air gap 8 is... The thickness of conductor tube 11 is The total magnetic reluctance of the magnetic circuit can then be expressed as:

[0086] (7)

[0087] In the formula, denoted as , where is the relative permeability of permanent magnet 3.

[0088] Equation (6) can be used to determine the remanent magnetic flux density of permanent magnet 3. and the thickness of permanent magnet 3 Calculate the magnetomotive force that permanent magnet 3 can provide. According to equation (7), the relative permeability of permanent magnet 3 can be used to determine the specific properties of the magnet. Thickness of permanent magnet 3 Thickness of air gap 8 Thickness of conductor tube 11 and cross-sectional area Calculate the total magnetic reluctance of the magnetic circuit .

[0089] Furthermore, according to the law of magnetic circuits, magnetic flux density It can be calculated using the following formula:

[0090] (8)

[0091] in, denoted as , where is the magnetic flux of the magnetic circuit.

[0092] As shown in equation (8), based on the residual magnetic flux density of permanent magnet 3 Relative permeability ,thickness and the thickness of air gap 8 Thickness of conductor tube 11 That is, the magnetic flux density can be calculated quantitatively. .

[0093] This embodiment, by analogy with Ohm's law in circuits and simultaneously introducing Kirchhoff's laws (i.e., the law of magnetic flux continuity and Ampere's circuital law) of magnetic circuits, constructs a magnetomotive force based on an equivalent one-dimensional linear magnetic circuit model. Total magnetic reluctance and magnetic flux density The calculation model can be used to calculate the magnetomotive force in the magnetic circuit. Total magnetic reluctance and magnetic flux density Quantitative calculations are performed, enabling the analysis of magnetic field problems in a manner similar to that of analytical circuits, allowing for rapid and accurate estimation of key parameters such as magnetic flux and air gap magnetic flux density.

[0094] In this embodiment, the geometric parameters specifically include the cross-sectional area of ​​the permanent magnet 3. Thickness of permanent magnet 3 Thickness of air gap 8 and the thickness of conductor tube 11 Material property parameters include the remanent magnetic flux density of permanent magnet 3. Relative permeability of magnets Conductor conductivity of conductor tube 11 In step S02, based on the Lorentz force formula, the calculation model for the eddy current damping force can be specifically expressed as follows:

[0095] (9)

[0096] in, This represents the cross-sectional area of ​​permanent magnet 3, that is, the projected area of ​​a single permanent magnet 3 onto the conductor. The number of magnetic pole pairs, Conductor conductivity Let be the residual magnetic flux density of permanent magnet 3. The air gap magnetic flux density is... The relative velocity between the permanent magnet 3 and the conductor tube 11 The thickness of air gap 8, The thickness of conductor tube 11, The thickness of permanent magnet 3. Let be the relative permeability of permanent magnet 3. The damping coefficient is... This is the eddy current damping force.

[0097] The model constructed based on equation (9) can characterize the effect of each parameter on the damping force. The influence law and sensitivity can be obtained, and the calculation formula of the damping coefficient of the eddy current damping force can be quantitatively obtained. The key to vibration reduction of transmission tower 7 is to provide damping force, and the key to determining the magnitude of the damping force is the damping coefficient of the eddy current damper. As shown in equation (9), the damping coefficient Cross-sectional area of ​​permanent magnet 3 Thickness of permanent magnet 3 Thickness of air gap 8 and the thickness of conductor tube 11 Isogeometry parameters and remanent magnetic flux density of permanent magnet 3 Relative permeability of magnets Conductor conductivity of conductor tube 11 Related to material property parameters. In this embodiment, the model constructed according to equation (9) is used to determine the damper's properties before actual fabrication and testing, based only on the geometric parameters (damping coefficient). Cross-sectional area of ​​permanent magnet 3 Thickness of permanent magnet 3 Thickness of air gap 8 and the thickness of conductor tube 11 ) and material property parameters (remanent magnetic flux density) Relative permeability of magnets Conductor conductivity of conductor tube 11 This allows for the precise quantitative calculation of the corresponding damping coefficient. The expected value can be obtained, thus accurately predicting the performance of the damper. This enables precise design, optimization, and performance prediction of eddy current dampers, solving the problem that traditional design methods rely on experience and trial and error.

[0098] Specifically, from equation (9), it can be seen that the damping force With the thickness of air gap 8 The damping force is inversely proportional to the square of the number of units. With the number of magnetic pole pairs Conductor conductivity Thickness of conductor tube 11 and the cross-sectional area of ​​permanent magnet 3 Proportional to, and also proportional to, the thickness of permanent magnet 3 and material property parameters remanent magnetic flux density The relationship is nonlinear, and therefore the damping coefficient can be determined using the aforementioned characteristics. The settings were adjusted. The geometric parameters and material properties of the permanent magnet 3, air gap 8, and conductor tube 11 were continuously adjusted, and the corresponding damping coefficient was calculated according to the eddy current damping force calculation model described above. The optimal damping coefficient is obtained by configuring the eddy current damper according to the optimal configuration values ​​of the geometric parameters and material properties corresponding to the optimal damping coefficient, thus providing the best vibration reduction effect.

[0099] In this embodiment, step S03 continuously adjusts the configuration values ​​of the geometric parameters and material property parameters of the permanent magnet 3, the air gap 8, and the conductor tube 11, and calculates the corresponding damping coefficient according to the eddy current damping force calculation model. The specific steps to obtain the optimal damping coefficient include:

[0100] Step S301. Determine the target damping coefficient Scope;

[0101] Step S302. Determine the number of pole pairs p and the cross-sectional area of ​​the permanent magnet 3 based on the installation space of the eddy current damper. The upper limit;

[0102] Step S303. Select a set of initial configuration values ​​of geometric parameters, material property parameters, and pole pair number p of permanent magnet 3, air gap 8, and conductor tube 11 in the target eddy current damper as the starting point for iteration. The geometric parameters include the cross-sectional area of ​​permanent magnet 3, the thickness of permanent magnet 3, the thickness of air gap 8, and the thickness of conductor tube 11. The material property parameters include the remanent magnetic flux density of permanent magnet 3, the relative permeability of magnet, and the conductor conductivity of conductor tube 11.

[0103] Step S304. Input the configuration values ​​of each parameter into the constructed eddy current damping force calculation model, and calculate the corresponding damping coefficient. ;

[0104] Step S305. Determine the currently calculated damping coefficient. If the preset requirements are met, proceed to step S306; otherwise, adjust any one or more of the configuration values ​​of the geometric parameters, material property parameters, and magnetic pole pair number p of the permanent magnet 3, air gap 8, conductor tube 11, and return to step S304 to re-input into the eddy current damping force calculation model for iterative calculation.

[0105] Step S306. Set the current damping coefficient As the optimal damping coefficient, and obtain the current damping coefficient. The geometric parameters, material properties, and the number of pole pairs p of the corresponding permanent magnet 3, air gap 8, and conductor tube 11 are taken as the optimal configuration values.

[0106] Specifically, in the design process of eddy current damper parameters, the target damping coefficient is first determined. The range (e.g., a damping of 500 Ns / m is required); then the geometric constraints of the installation space (e.g., the length and diameter of the rods available for mounting the damper) are defined to determine the number of pole pairs. and permanent magnet 3 dimensions The upper limit can be determined; the choice of materials can also be determined based on cost constraints, such as the choice of permanent magnet material type and conductor material type; then, based on the constraints, a preliminary set of design parameters is selected as the starting point for iteration, including the number of magnetic pole pairs. Dimensions of permanent magnet 3 (including the cross-sectional area of ​​permanent magnet 3) and thickness 3. Permanent magnet material (determine the remanent magnetic flux density) and relative permeability (etc.), conductor materials (determining conductivity) ) and conductor tube 11 Design air gap thickness Substitute the selected parameters into the eddy current damping force calculation model to calculate the theoretical damping coefficient. Adjusting the configuration of each parameter will adjust the corresponding damping coefficient. Finally, based on the determined parameters, a physical eddy current damper product is designed, thus obtaining an eddy current damper with the required vibration reduction effect.

[0107] Furthermore, for the low-speed case, it can be seen from equation (9) that:

[0108] 1. Eddy current damping coefficient and conductor conductivity Proportional to the remanent magnetic flux density of the permanent magnet It is proportional to the square of.

[0109] 2. Thickness of permanent magnet 3 The thicker the material, the larger the damping coefficient, but the relationship is not linear. To maximize the damping coefficient, it is necessary to ensure... Continue to increase at this point It has little effect on the damping coefficient.

[0110] 3. Air gap The smaller the value, the larger the damping coefficient. At that time, its impact is negligible.

[0111] 4. Conductor tube thickness The effect on the damping coefficient is non-monotonic. When When, the damping coefficient and Approximately proportional The larger the value, the larger the damping coefficient; as As the damping factor continues to increase, it no longer increases proportionally. This is because... An increase in will also lead to an increase in magnetic reluctance; when When the damping coefficient is at its maximum, if If the damping coefficient is increased further, it will actually decrease.

[0112] It should be noted that the low-speed damping force calculated according to equation (9) will be larger than the actual value. Even without considering the nonlinear effect at high speed, the following errors will still exist: (1) Since the magnetic flux in the calculation model follows the assumed magnetic path, in reality, the magnetic field lines will not be completely perpendicular to the surface of the permanent magnet 3 or the surface of the conductor tube. The perpendicular component is smaller than the calculated value and is not limited to the projected area of ​​the permanent magnet 3; (2) The calculation model expands the radially arranged magnetic poles and maps them into a straight line, and uses a uniform magnetic path cross-sectional area. Calculations were performed, but in reality, the cross-sectional area varies; the projected area inside permanent magnet 3 is less than... Meanwhile, the cross-sectional area of ​​the magnetic circuit in the conductor tube increases from the inside to the outside.

[0113] Therefore, the damping force or damping coefficient can be calculated according to the calculation model of Equation (9). The calculation accuracy can be further improved by selecting damper devices and parameter dimensions.

[0114] Specifically, based on the above derivation, the damping coefficient and the conductor conductivity and the residual magnetic flux density of permanent magnets The thickness is proportional to the square of the magnetic field. Preferably, the conductor tube 11 can be made of a high-conductivity material, and the permanent magnet 3 is preferably a high-performance permanent magnet material with high remanence and high coercivity, such as neodymium iron boron (NdFeB). In some applications with extremely high temperature requirements, samarium cobalt (SmCo) can also be considered. The thickness of the permanent magnet 3... This would require a value significantly greater than the sum of the air gap 8 and the conductor thickness. To achieve optimal performance.

[0115] Specifically, it also includes configuring the thickness of the permanent magnet 3 according to the following rules. : Configure the thickness of permanent magnet 3 The initial value is continuously increased, and the following condition is met: ,in The thickness of conductor tube 11, The thickness of permanent magnet 3. For example, a preset coefficient greater than 1. Choosing option 2 ensures that the magnetic potential primarily falls onto the air gap 8 and the conductor, rather than being wasted inside the magnet. Furthermore, increasing the thickness of the permanent magnet 3... The corresponding damping coefficient The optimal thickness of the permanent magnet 3 is determined when the increase is less than a preset ratio (e.g., 5%). This can effectively save costs and reduce the weight of the damper. Preferably, the thickness of the permanent magnet 3 can be determined. , After determining the thickness of air gap 8, it can be done according to... The optimal thickness of a conductor tube 11 was calculated. _optimal. If the optimal thickness cannot be used due to process, cost, or weight considerations, the thickness of conductor tube 11 can be determined according to the following rules. If the thickness Less than the optimal thickness When the value is _optimal, the conductor thickness should be increased as much as possible; if the thickness is... Greater than the optimal thickness If the thickness is optimal, a smaller thickness can be used to reduce weight.

[0116] Specifically, based on the above derivation of the air gap thickness This is the most sensitive parameter and needs to be configured to a minimum value.

[0117] High-precision machining and assembly processes can be used to ensure an extremely small and uniform air gap 8. Preferably, a non-metallic wear-resistant bearing sleeve (such as POM or PTFE) made of POM (polyoxymethylene) or PTFE (polytetrafluoroethylene) can be integrated into the moving parts as a guide mechanism. Compared with the traditional use of direct metal contact, this can ensure an extremely small installation air gap 8 (e.g., 0.5-2mm) between the magnet and the conductor, and also ensure that no metal contact and wear occur under long-term vibration, permanently maintaining the air gap value of the initial design.

[0118] The simplified mathematical model of an eddy current damper can be expressed as follows: Figure 4 As shown, m, c, and k are the mass, damping, and stiffness coefficients of the main structure, respectively. Let m be the mass, damping coefficient, and stiffness coefficient of the eddy current damper, respectively. After installing the eddy current damper on transmission tower 7 (mass m, damping coefficient c, stiffness k), the vibration control equation of the eddy current damper can be expressed by the following formula:

[0119] 10)

[0120] In the formula, Indicates the displacement of the main structure. Indicates the speed of the main structure. Indicates the acceleration of the main structure; Represents the damper displacement. Represents the damper speed. Represents the damper acceleration. The external excitation force that causes the main structure to vibrate.

[0121] Equation (10) above can describe the damper (whose mass is Additional stiffness is Additional damping is After being installed on transmission tower 7 (mass m, damping c, stiffness k), the entire coupled system under wind-induced vibration excitation... The motion law under the condition. Based on this equation, the vibration response (such as displacement) of the entire system under excitation after the damper is added to transmission tower 7 can be obtained. ,speed (e.g., acceleration, etc.), thus the vibration reduction effect of the damper can be evaluated.

[0122] In formula (10) The physical essence of the term corresponds to the eddy current damping force. .in, The relative velocity between the permanent magnet 3 and the conductor tube 11 (or equivalent moving part) corresponds to the speed of the relative velocity between them. Then the damping coefficient calculated by equation (9) It is the key input parameter of the system equation (10). After determining the optimal damping coefficient according to step S03, the vibration reduction effect of the entire transmission tower 7 can be further effectively determined.

[0123] Combined with equation (10), we can obtain equation (11) based on the principles of dynamics:

[0124] (11)

[0125] In the formula, Represents the amplitude of the main structure. Represents static deformation. The frequency ratio representing the ratio of the eddy current damper to the main structure, Represents the external excitation frequency. This represents the mass ratio of the eddy current damper to the main structure. This represents the damping ratio of the eddy current damper. The damping ratio can be calculated using formula (12):

[0126] (12)

[0127] In the formula, Represents the damper's vibration frequency. This represents the velocity at which the conductor plate cuts the magnetic field lines. Represents Lorentz force.

[0128] Wind-induced vibration is a continuous and periodic energy input. Suppressing wind-induced vibration requires continuously and efficiently dissipating the energy input by the wind. Based on the above derivation, this embodiment, by installing an eddy current damper on the steel pipe member of the transmission tower 7, allows the eddy current damper to continuously convert the continuous wind energy into heat energy through the eddy current effect, and the amount of energy dissipated is proportional to the damping coefficient. It is proportional to the square of the relative velocity, and is extremely efficient. However, since the damping c of the original transmission tower structure is usually very small, it leads to severe wind-induced vibration. By installing an eddy current damper, a huge additional damping can be added to the system. The additional damping Dynamic coupling can significantly improve the equivalent damping ratio of the entire system, thereby greatly reducing the resonance response amplitude. By applying a force opposite to the wind load to the main structure at the installation point, part of the wind-induced vibration force is directly offset, thus effectively suppressing wind-induced vibration and ensuring safe and stable operation under actual wind speeds. Furthermore, the optimal damping coefficient is determined using the method described in this embodiment. This allows for optimal vibration reduction performance, ensuring that it can achieve the best vibration reduction effect in actual dynamic systems.

[0129] like Figures 5 to 11As shown, the vibration damper for the transmission tower steel pipe in this embodiment includes a cylindrical assembly 1 and a connecting assembly 2 connected to the steel pipe. The connecting assembly 2 is connected to one end of the cylindrical assembly 1. A permanent magnet 3 is disposed inside the cylindrical assembly 1, and mass blocks 4 are disposed on both sides of the permanent magnet 3. An elastic element 5 is abutting between the mass blocks 4 and the end of the cylindrical assembly 1. See details... Figure 9 An elastic element 5 is provided between the upper mass block 4 and the upper end cover of the cylinder assembly 1, and an elastic element 5 is provided between the lower mass block 4 and the lower end cover of the cylinder assembly 1. The cylinder assembly 1 includes a conductor tube 11 that cooperates with the permanent magnet 3, and an air gap 8 is formed by the air gap between the mass block 4 and the conductor tube 11.

[0130] Existing vibration dampers for transmission tower steel pipes mostly involve adding vortex interference devices to the structure to reduce the vibration response of the steel pipe, as well as some viscoelastic dampers. Existing eddy current-based steel pipe dampers are mostly plate-type eddy current dampers. Plate-type eddy current dampers are suitable for vibration reduction of large structures, but they have problems such as inconvenient installation and application difficulties in the eddy-induced vibration reduction of small steel pipe components. In addition, the damper structure is simple and singular, and it cannot form a resonance effect with the steel pipe structure, resulting in poor vibration reduction effect and low reliability. It is difficult to directly apply it to the control of eddy-induced vibration of steel pipes, and the actual reliability is unknown.

[0131] The steel pipe damping vibration isolator of this embodiment is based on the principle of eddy currents. It has an overall cylindrical structure, making installation convenient. Its volume is much smaller than existing plate array dampers, avoiding limitations imposed by installation space and conditions. It is also lighter, minimizing its impact on the load on the steel pipe. Furthermore, the elastic element 5, permanent magnet 3, and mass block 4 are all easily adjustable. On one hand, they can be adjusted for different steel pipe vibration frequencies, specifically suppressing the vibration of each individual steel pipe without affecting the overall or local structure of the steel pipe tower. On the other hand, they can resonate with the steel pipe structure to be damped, resulting in better vibration reduction performance. The modular replacement design also makes it easier to address different specific steel pipe vibration situations, effectively preventing steel pipe vibration.

[0132] like Figure 5 and Figure 6 As shown, the cylinder assembly 1 consists of two sets: a vertical damping cylinder assembly 16 and a horizontal damping cylinder assembly 17. The vertical damping cylinder assembly 16 is arranged along the height of the transmission tower 7, while the horizontal damping cylinder assembly 17 is arranged intersecting with it. The vertical damping cylinder assembly 16 and the horizontal damping cylinder assembly 17 are interconnected by a guide sliding member 6. The vertical damping cylinder assembly 16 and the horizontal damping cylinder assembly 17 move along their respective arrangement directions, allowing the damper to slide stably in both directions. This achieves bidirectional vibration control and decouples the movements in the intersecting two directions, solving the problem that existing dampers cannot effectively reduce vibration in both directions.

[0133] In other embodiments, the cylindrical assembly 1 may also be arranged as a group, with the group of cylindrical assemblies 1 arranged along the height or horizontal direction of the transmission tower 7 to achieve vertical or horizontal vibration reduction.

[0134] In this embodiment, the vertical damping cylinder assembly 16 and the horizontal damping cylinder assembly 17 are arranged orthogonally. The guide sliding member 6 is a guide sliding plate, and the two end faces of the guide sliding plate are respectively provided with a vertical mating part 61 and a horizontal mating part 62. The mass block 4 of the vertical damping cylinder assembly 16 is provided with a vertical guide rail 161, and the mass block 4 of the horizontal damping cylinder assembly 17 is provided with a horizontal guide rail 171. The vertical mating part 61 is slidably engaged with the vertical guide rail 161, and the horizontal mating part 62 is slidably engaged with the horizontal guide rail 171. In other embodiments, the setting angle of the vertical damping cylinder assembly 16 and the horizontal damping cylinder assembly 17 can also be adjusted according to the actual vibration reduction requirements.

[0135] This invention employs a "dual-track-cross connector" structure to achieve motion decoupling and avoid motion interference between the vertical damping cylinder assembly 16 and the lateral damping cylinder assembly 17. Specifically, when the structure experiences vertical vibration, the force is transmitted to the vertical damping cylinder assembly 16 through the sliding engagement of the vertical fitting part 61 with the vertical guide rail 161, while the lateral fitting part 62 is allowed to "float" freely in the lateral direction, almost without triggering the lateral damping cylinder assembly 17. Conversely, when lateral vibration occurs, the force is transmitted to the lateral damping cylinder assembly 17 through the sliding engagement of the lateral fitting part 62 with the lateral guide rail 171, while the vertical fitting part 61 is allowed to "float" freely in the vertical direction, almost without triggering the vertical damping cylinder assembly 16. This avoids mutual interference between the damping cylinder assemblies in the two directions, ensuring that the pure and efficient damping force provided by the damper in any single direction of vibration is obtained.

[0136] Meanwhile, the dual dampers are integrated into a single unit via the guide sliding component 6. This design is simple and compact, saves space, facilitates installation, reduces the overall weight and cost of the damper, and ensures stable sliding of the damper in two orthogonal directions. The mechanical connection method of the guide sliding plate (double groove-double convex rail) replaces the traditional vulnerable hinge structure, which improves the overall stability, anti-overturning ability, and environmental durability of the damper, fully considering the application scenarios of the transmission tower 7.

[0137] Furthermore, such as Figure 9 As shown, the permanent magnet 3 is an annular permanent magnet, and the mass blocks 4 on both sides are fastened by threaded fasteners 41 (for example, the side of the mass block 4 away from the permanent magnet 3 has an annular protrusion 42 (specifically the upper part of the upper mass block 4 and the lower part of the lower mass block 4). The annular protrusion 42 has a flexible anti-collision block 43 (for example, it can be a rubber block, plastic block, etc.). The flexible anti-collision block 43 can prevent rigid collisions between the mass block 4 and the end cap 14 of the cylinder assembly 1, further improving reliability.

[0138] In a preferred embodiment, the elastic element 5 is a helical spring, with one end of the helical spring fitted around the outer periphery of the annular protrusion 42. The annular protrusion 42 provides a mounting base for the flexible anti-collision block 43 and also provides positioning for the helical spring, preventing displacement under stress. This design is simple and reliable. More preferably, protrusions or grooves can be provided on the end caps 14 of the cylindrical assembly 1 to also provide positioning for the end of the helical spring furthest from the mass block 4.

[0139] Furthermore, in this embodiment, the cylindrical assembly 1 also includes a guide cylinder 12, which is located inside the conductor tube 11. The guide cylinder 12 can provide guidance for the reciprocating movement of the mass block 4 and the permanent magnet 3, making the movement process more stable and smooth.

[0140] Furthermore, in this embodiment, a protective cylinder 13 is provided on the outside of the conductor tube 11. The protective cylinder 13 serves two purposes: firstly, to protect the internal components from damage, and secondly, to seal the magnetic field lines.

[0141] As a preferred embodiment, the conductor tube 11 can be an aluminum cylinder or a copper cylinder, which is beneficial for polymerizing the magnetic circuit and cutting the magnetic field lines to induce eddy currents, and is lightweight; the guide cylinder 12 is a polytetrafluoroethylene cylinder, which is heat and cold resistant, suitable for complex outdoor environments, and has a low coefficient of friction, which is beneficial for reducing the wear of the mass block 4; the protective cylinder 13 can be an iron cylinder or a steel cylinder.

[0142] Furthermore, in this embodiment, the lower end of the cylindrical assembly 1 is provided with a detachable end cap 14. After removing the end cap 14, it is convenient to replace the elastic element 5, permanent magnet 3, and mass block 4 inside the cylindrical assembly 1. Preferably, the lower end cap 14 is threadedly connected to the protective cylindrical body 13, which has good connection reliability and is convenient for disassembly and assembly. As for the upper end cap 14, it can be an integral structure with the protective cylindrical body 13 or it can also be threadedly connected to the protective cylindrical body 13.

[0143] Furthermore, in this embodiment, the detachable end cap 14 is equipped with a sealing element 15 (such as a sealing ring, sealing strip, etc.) to ensure the sealing between the end cap 14 and the lower end of the cylinder assembly 1, and to prevent dust and other foreign objects from entering the interior of the cylinder assembly 1.

[0144] Furthermore, in this embodiment, the connecting component 2 includes a clamp. Using a clamp facilitates the installation of the cylinder component 1 onto the steel pipe to be vibration-damped. Of course, in other embodiments, the connecting component 2 can also take other forms, as long as it can be installed onto the steel pipe to be vibration-damped.

[0145] The working principle of the steel pipe damping vibration absorber in this embodiment is as follows:

[0146] When the steel pipe vibrates under external load excitation, the mass block 4 will undergo a certain displacement and provide inertial force, enabling it to generate relative displacement with the steel pipe. The upper and lower elastic elements 5 can automatically compress and stretch according to the vibration of the steel pipe, providing restoring force when the mass block 4 and the steel pipe structure generate relative displacement, so that the steel pipe and the damping vibration isolator can maintain common vibration as a two-degree-of-freedom system. At the same time, the unique stiffness of the two elastic elements 5 connected in series can also adjust the frequency of this two-degree-of-freedom system, improve its vibration response characteristics, and restore the steel pipe to its original position. Eddy current damping mainly plays the role of dissipating vibration energy. When the whole composed of the mass block 4 and the ring permanent magnet 3 moves relative to the steel pipe, the conductor tube 11 can aggregate the magnetic circuit and cut the magnetic field lines to induce eddy currents. At the same time, the eddy currents will also excite the induced magnetic field. The outer protective cylinder 13 plays the role of sealing the magnetic field lines. According to Lenz's law, under the influence of the induced magnetic field, a force is generated on the steel pipe structure that opposes the relative motion between the annular permanent magnet 3 and the conductor pipe 11 and the protective cylinder 13, i.e., a damping force is applied to the steel pipe structure. Since the conductor pipe 11 has resistance, according to the law of conservation of energy, the mechanical energy converted from magnetic energy is ultimately dissipated as heat energy. The transmission tower steel pipe vibration damper effectively absorbs the energy of the steel pipe vibration through resonance and dissipates it through its own eddy current damping, thereby achieving the purpose of rapidly attenuating the energy of the steel pipe structure and controlling its vibration.

[0147] See details Figure 12 The comparison curves of the vortex-induced vibration response of the transmission tower steel pipe with and without the first-order vibration damper (vortex vibration range) were obtained. The root mean square of the acceleration response was calculated at each wind speed with a data acquisition time of 30 seconds to reflect the degree of vibration response of the steel pipe at each wind speed. The smaller the root mean square of the acceleration response of the tested steel pipe, the better the vibration reduction effect. The vibration reduction results show that after the installation of the eddy current damper, the vibration reduction rate of the tested steel pipe exceeded 73%, especially the first-order (mass ratio 0.01) and second-order (mass ratio 0.02) vibration reduction effects exceeded 90%. In practice, installing this type of transmission tower steel pipe vibration damper on the steel pipe members can effectively suppress vibration and protect the structure to work safely and stably in the actual environment.

[0148] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for vibration reduction of steel pipes in transmission towers, characterized in that the steps include... include: Construct an equivalent one-dimensional linear magnetic circuit model of an eddy current damper, wherein the equivalent one-dimensional linear magnetic circuit model is composed of an air gap magnetoresistive element. Magnetic resistance of conductor tube Permanent magnet reluctance and the magnetomotive force provided by the permanent magnet It is composed of series connection, which consists of air gap magnetoresistive Magnetic resistance of conductor tube Permanent magnet reluctance The series connection constitutes the total magnetic reluctance The magnetomotive force The total magnetic reluctance is calculated based on the geometric parameters and material properties of the permanent magnet. It is calculated based on the geometric parameters of the permanent magnet, air gap, and conductor tube; A calculation model for eddy current damping force is constructed, wherein the calculation model for eddy current damping force is based on the air gap magnetic flux density. With eddy current damping force Relationship model and damping coefficient With eddy current damping force The relationship model between the air gap magnetic flux density According to the magnetomotive force and the total magnetic resistance Calculated; The configuration values ​​of the geometric parameters and material properties of the permanent magnet, air gap, and conductor tube are continuously adjusted, and the corresponding damping coefficient is calculated according to the eddy current damping force calculation model. Until the optimal damping coefficient is obtained; configure the eddy current damper according to the optimal configuration values ​​of the geometric parameters and material property parameters of the permanent magnet, air gap, and conductor tube corresponding to the optimal damping coefficient, and set the configured eddy current damper on the steel pipe structure of the transmission tower to achieve vibration reduction. Based on the characteristic that the permanent magnets in the eddy current damper are periodically and alternately distributed in the circumferential direction, the problem of the three-dimensional circumferentially distributed magnetic field is simplified into a two-dimensional planar model containing rectangular cross-sectional elements of magnetic pole pairs. Half of the adjacent magnetic poles are taken as the analysis unit, and the two-dimensional planar model is abstracted into a one-dimensional linear model to construct the equivalent one-dimensional linear magnetic circuit model. The magnetomotive force The calculation expression is: ， in, The residual magnetic flux density of the permanent magnet. The thickness of the permanent magnet. The vacuum permeability; The total magnetic reluctance The calculation expression is: ， in, The relative permeability of the permanent magnet. The thickness of the air gap. The thickness of the conductor tube, The cross-sectional area of ​​the permanent magnet, air gap, and conductor tube; The air gap magnetic flux density The calculation expression is: ， in, The magnetic flux of the magnetic circuit; The calculation expression for the eddy current damping force calculation model is as follows: ， in, Let be the cross-sectional area of ​​the permanent magnet. The number of magnetic pole pairs, The conductor conductivity of the conductor tube. The relative velocity between the permanent magnet and the conductor tube.

2. The vibration reduction method for transmission tower steel pipes according to claim 1, characterized in that, The geometric parameters include the cross-sectional area of ​​the permanent magnet, the thickness of the permanent magnet, the thickness of the air gap, and the thickness of the conductor tube. The material property parameters include the remanent magnetic flux density of the permanent magnet, the relative permeability of the magnet, and the conductor conductivity of the conductor tube.

3. The vibration reduction method for transmission tower steel pipes according to any one of claims 1 to 2, characterized in that, The configuration values ​​of the geometric parameters and material properties of the permanent magnet, air gap, and conductor tube are continuously adjusted, and the corresponding damping coefficient is calculated according to the eddy current damping force calculation model. Until the optimal configuration values ​​for each parameter are obtained, including: Determine the target damping coefficient Scope; The number of magnetic pole pairs is determined based on the installation space of the eddy current damper. and permanent magnet cross-sectional area The upper limit; The initial configuration values ​​of the geometric parameters, material properties, and number of pole pairs p of the permanent magnet, air gap, and conductor tube in a target eddy current damper are selected as the starting point for iteration. The geometric parameters include the cross-sectional area of ​​the permanent magnet, the thickness of the permanent magnet, the thickness of the air gap, and the thickness of the conductor tube. The material properties include the remanent magnetic flux density of the permanent magnet, the relative permeability of the magnet, and the conductor conductivity of the conductor tube. Input the configured values ​​of each parameter into the constructed eddy current damping force calculation model to calculate the corresponding damping coefficient. ; Determine the currently calculated damping coefficient Does it meet the preset requirements? If the calculated damping coefficient Meeting the preset requirements yields the optimal damping coefficient, as well as the corresponding geometric parameters, material properties, and number of pole pairs for the permanent magnet, air gap, and conductor tube. Output the optimal configuration value; If the calculated damping coefficient If the preset requirements are not met, adjust the geometric parameters, material properties, and number of pole pairs of the permanent magnet, air gap, and conductor tube. Any one or more configuration values ​​from the configuration values ​​are re-entered into the eddy current damping force calculation model for iterative calculation.

4. The vibration reduction method for transmission tower steel pipes according to any one of claims 1 to 2, characterized in that, It also includes configuring the thickness of the permanent magnet according to the following rules. Thickness of the permanent magnet The initial value is continuously increased, and the following condition is met: ,in, A preset coefficient greater than 1 is used when the thickness of the permanent magnet is increased. The corresponding damping coefficient The optimal thickness of the permanent magnet is determined when the increase is less than a preset ratio. The thickness of the conductor tube according to Calculated.

5. A vibration damper for transmission tower steel pipes using the method described in any one of claims 1 to 4, characterized in that, The device includes a cylindrical assembly and a connecting assembly for connecting to a steel pipe. The connecting assembly is connected to one end of the cylindrical assembly. The cylindrical assembly contains a permanent magnet, and mass blocks are provided on both sides of the permanent magnet. An elastic element is provided between the mass blocks and the end of the cylindrical assembly. The cylindrical assembly includes a conductor tube that cooperates with the permanent magnet. An air gap is formed by the air gap between the mass blocks and the conductor tube.

6. The vibration damper for transmission tower steel pipes according to claim 5, characterized in that, The cylindrical assembly consists of two sets: a vertical damping cylinder assembly arranged along the height of the transmission tower, and a horizontal damping cylinder assembly arranged intersecting the vertical damping cylinder assembly. The vertical damping cylinder assembly and the horizontal damping cylinder assembly are connected to each other by guide sliding members and move along their respective arrangement directions.

7. The vibration damping device for transmission tower steel pipes according to claim 6, characterized in that, The vertical damping cylinder assembly and the horizontal damping cylinder assembly are arranged orthogonally. The guide sliding member is a guide sliding plate. The two end faces of the guide sliding plate are respectively provided with a vertical mating part that slides with the vertical damping cylinder assembly and a horizontal mating part that slides with the horizontal damping cylinder assembly.

8. The vibration damper for transmission tower steel pipes according to claim 5, characterized in that, The permanent magnet is a ring-shaped permanent magnet, and the mass blocks on both sides are connected by threaded fasteners, which pass through the middle of the ring-shaped permanent magnet. The mass block has an annular protrusion on the side away from the permanent magnet, and a flexible anti-collision block is provided in the annular protrusion.

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