Lightweight tuning viscous mass damper spacer and optimal parameter determination method thereof

Abstract

The invention relates to the technical field of electric power engineering, in particular to a light-weight tuned viscous mass damping spacer and an optimal parameter determination method of the light-weight tuned viscous mass damping spacer. Axial movement generated by the lead screw under displacement driving of the power transmission line is converted into high-speed rotating movement of the rotating flywheel, so that viscous fluid in the viscous damping bin generates shear resistance, damping force opposite to the vibration direction is formed, input energy brought by vibration of the power transmission line is dissipated through the damping force, and the deicing jump height is restrained. The composite phase-to-phase spacer is used for transmitting damping force generated by the ball screw-flywheel type tuned viscous mass damper to the power transmission conductor to cooperatively suppress ice-shedding jump vibration. Through the synergistic effect of the ball screw-flywheel type tuning viscous mass damper and the composite phase-to-phase spacer, the deicing jump height of the power transmission line is effectively reduced, and safe and stable operation of the power transmission line is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power engineering, and in particular to a lightweight tuned viscous mass damping spacer and a method for determining optimal parameters thereof. Background Art

[0002] In power transmission systems, transmission lines are prone to icing under extreme climatic conditions, especially low temperatures. When supercooled water droplets in the air contact the surface of overhead wires, which are below 0°C, they release energy and condense to form ice. With temperature fluctuations, natural wind forces, or vibrations caused by human factors, the ice will fall off unevenly, causing large vertical vibrations in the wires. This vibration not only applies huge tensile forces to transmission structures such as transmission towers, insulator strings, and hardware, but also increases the risk of structural damage such as hardware cracking, crossarm breakage, conductor breakage, and even transmission tower damage or collapse. In addition, when the conductors shed ice and jump, the air gap between the phase conductors or the ground wire decreases. If it is less than the electrical insulation clearance requirement, it will cause electrical accidents such as flashover, tripping, and conductor burns, seriously threatening the stable operation of the power system.

[0003] To address the problem of conductor jumping due to ice shedding, existing technologies mainly adopt the methods of adding interphase spacers and setting suspended tuned mass dampers under the conductors to deal with the problem of conductor jumping due to ice shedding, but both have obvious limitations. Although the traditional method of adding interphase spacers can suppress the vibration response to a certain extent, it cannot quickly attenuate the vibration of the conductor and still needs to rely on the damping characteristics of the conductor itself for slow free attenuation. The traditional method of adding a suspended tuned mass damper under the conductor requires the addition of a larger mass block, which increases the deadweight load of the conductor. Moreover, since the mass block of the suspended tuned mass damper may produce a larger vertical displacement than the conductor during the vibration process, there is a risk of collision with the conductor, which also brings inconvenience to on-site maintenance and operation.

[0004] In summary, the existing transmission line ice shedding jump suppression technology has many shortcomings in application. Therefore, it is urgent to develop a new device that is more efficient, lightweight and easy to maintain to more effectively suppress the ice shedding jump phenomenon of transmission lines and ensure the safe and stable operation of transmission lines. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a lightweight tuned viscous mass damping spacer and a method for determining the optimal parameters thereof.

[0006] In a first aspect, the present invention provides a lightweight tuned viscous mass damper spacer, comprising: a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer connected by a spring unit; the ball screw-flywheel type tuned viscous mass damper includes a rotating flywheel, balls, a screw, a guide rail, and a viscous damping chamber;

[0007] The ball screw-flywheel type tuned viscous mass damper is used to convert the axial movement of the screw driven by the displacement of the transmission line into the high-speed rotational motion of the rotating flywheel when the transmission line experiences ice shedding jump vibration, so that the viscous fluid in the viscous damping chamber generates shear resistance due to the rotation of the rotating flywheel, forming a damping force opposite to the vibration direction. The damping force dissipates the input energy caused by the transmission line vibration, thereby suppressing the ice shedding jump height and accelerating the vibration attenuation;

[0008] The composite interphase spacer is used to limit the asymmetric displacement of the transmission conductor after de-icing jump by rigidly connecting the upper and lower phase transmission conductors, and transmit the damping force generated by the ball screw-flywheel type tuned viscous mass damper to the transmission conductor through the spring unit, forming a dynamic coupling between the damping effect and the vibration of the transmission conductor, and synergistically suppressing the de-icing jump vibration.

[0009] In a further embodiment, the composite interphase spacer spans the upper and lower phase transmission conductors and is installed at the sag of the upper and lower phase transmission conductors, and the ball screw-flywheel type tuned viscous mass damper is suspended between the lower phase transmission conductor and the composite interphase spacer through a spring unit.

[0010] In a further embodiment, the rotating flywheel is rigidly connected to the end of the screw by mechanical fixing to form a stable rotating system;

[0011] The rotating flywheel serves as a mass amplification system of the inertia capacity, and is used to cooperate with the viscous fluid in the viscous damping chamber to perform energy consumption and vibration reduction.

[0012] In a further embodiment, the ball is slidably connected between the screw and the viscous damping chamber, and the other end of the screw forms a sliding fit with the guide rail in the viscous damping chamber through the ball, completing the coupling of axial movement and rotational motion.

[0013] In a further embodiment, the composite interphase spacers are made of insulating material, and the insulating material is used to prevent short circuits or leakage between the transmission conductors.

[0014] In a second aspect, the present invention provides a method for determining optimal parameters of a lightweight tuned viscous mass damping spacer, the method comprising:

[0015] According to the design drawings of the transmission tower line system, a finite element calculation model of the conductor is established, and modal vibration analysis is performed on the finite element calculation model of the conductor to obtain the first-order modal parameters of the conductor;

[0016] An uncontrolled ice shedding jump response analysis is performed based on the first-order modal parameters to determine a target jump height ratio of the conductor when ice shedding jumps;

[0017] Based on the target jump height ratio, the pole placement method is used to optimize the parameters of the ball screw-flywheel type tuned viscous mass damper to obtain the optimal parameter configuration scheme for suppressing ice shedding jump; the optimal parameter configuration scheme includes the optimal stiffness ratio, the optimal damping ratio, and the optimal inertia-to-mass ratio;

[0018] Determining actual physical parameters of the ball screw-flywheel type tuned viscous mass damper according to the optimal inertia-mass ratio, and inputting the actual physical parameters into a pre-established conductor-damper spacer coupling dynamic model including the ball screw-flywheel type tuned viscous mass damper and the composite interphase spacer;

[0019] The shedding jump response is analyzed under controlled and uncontrolled conditions using the conductor-damper spacer coupling dynamic model, and the shedding jump suppression results are obtained.

[0020] When the de-icing jump suppression results meet the preset performance indicators of the conductor, the optimal parameter configuration solution is output.

[0021] In a further embodiment, the actual physical parameters include an equivalent radius of the rotating flywheel, a physical mass of the rotating flywheel, a lead of a screw and a rotational damping coefficient of a viscous material.

[0022] In a further embodiment, the step of optimizing the parameters of the ball screw-flywheel tuned viscous mass damper using a pole placement method based on the target jump height ratio to obtain an optimal parameter placement solution for suppressing ice shedding jumps includes:

[0023] A conductor-damper spacer coupled dynamic model is constructed, which includes a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer. The governing equations of the deicing jump motion of the conductor-damper spacer coupled dynamic model are determined based on the first-order modal parameters of the conductor.

[0024] Performing Laplace transform on the de-icing jump motion control equation to obtain the conductor displacement frequency domain transfer function;

[0025] Performing eigenvalue analysis on the conductor displacement frequency domain transfer function to obtain a real part of the eigenvalue, and defining a vibration attenuation rate based on the real part of the eigenvalue;

[0026] Under the constraint that the actual jump height ratio is no greater than the target jump height ratio, the optimal stiffness ratio, optimal damping ratio, and optimal inertia-to-mass ratio of the ball screw-flywheel tuned viscous mass damper are solved by the pole placement method with maximizing the vibration attenuation rate as the optimization goal.

[0027] In a further embodiment, the de-icing jump motion control equation is specifically:

[0028]

[0029] Where m l is the first-order modal mass of the lower-phase transmission conductor; is the second-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; c l is the damping coefficient of the upper phase conductor; k is the first-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; l is the first-order modal stiffness of the lower phase transmission conductor; u l is the first-order modal displacement of the lower-phase transmission conductor; k f is the stiffness of the upper spacer; u u is the first-order modal displacement of the upper phase transmission conductor; k t is the stiffness of the ball screw-flywheel type tuned viscous mass damper; u t is the vertical displacement of the ball screw-flywheel type tuned viscous mass damper; F s is the impact load; m t is the inertia coefficient of the ball screw-flywheel type tuned viscous mass damper; is the second-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; c t is the damping coefficient of the ball screw-flywheel type tuned viscous mass damper; is the first-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; m u is the first-order modal mass of the upper phase transmission conductor; is the second-order derivative of the first-order modal displacement of the upper-phase transmission conductor with respect to time; c u is the damping coefficient of the lower phase transmission line; k is the first-order derivative of the first-order modal displacement of the upper phase transmission line with respect to time; u is the first-order modal stiffness of the upper phase transmission line.

[0030] In a further embodiment, the actual jump height ratio at the conductor sag is calculated based on the ratio between the maximum vertical displacement at the lower phase transmission conductor sag after vibration reduction and the vertical displacement at the lower phase transmission conductor sag before vibration reduction.

[0031] The present invention provides a lightweight tuned viscous mass damping spacer and a method for determining its optimal parameters. The lightweight tuned viscous mass damping spacer comprises a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer. The ball screw-flywheel type tuned viscous mass damper is used to convert the axial movement of the screw generated by the displacement drive of the transmission line into high-speed rotational motion of a rotating flywheel when the transmission line experiences de-icing jump vibration, so that the viscous fluid in the viscous damping chamber generates shear resistance due to the rotation of the rotating flywheel, forming a damping force opposite to the vibration direction, and dissipating the input energy caused by the vibration of the transmission line through the damping force, thereby suppressing the de-icing jump height and accelerating the vibration attenuation. The composite interphase spacer is used to transmit the damping force generated by the ball screw-flywheel type tuned viscous mass damper to the transmission line through a spring unit, so as to synergistically suppress the de-icing jump vibration. Compared with the existing technology, this lightweight tuned viscous mass damping spacer effectively dissipates the vibration energy of the transmission line, suppresses the de-icing jump height and accelerates the vibration attenuation process through the synergistic effect of the ball screw-flywheel type tuned viscous mass damper connected by the spring unit and the composite phase spacer, thereby significantly improving the operating stability of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the structure of a lightweight tuned viscous mass damping spacer rod provided by an embodiment of the present invention;

[0033] Figure 2 This is a flow chart of a method for determining optimal parameters of a lightweight tuned viscous mass damping spacer provided by an embodiment of the present invention;

[0034] Figure 3 Schematic diagram of ice shedding jump response suppression for upper and lower phase conductors provided by an embodiment of the present invention;

[0035] Figure 4 This is a flowchart of a process for determining optimal parameters of a lightweight tuned viscous mass damping spacer provided by an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the ice shedding jump time history at the sag of a transmission line installed with only rigid spacers provided by an embodiment of the present invention;

[0037] Figure 6 This is a schematic diagram of the ice shedding jump time history at the sag of a conductor installed with a lightweight tuned viscous mass damping spacer provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention in detail with reference to the accompanying drawings. The embodiments are provided for illustrative purposes only and are not to be construed as limiting the present invention. The accompanying drawings are provided for reference and illustration only and do not constitute a limitation on the scope of protection of the present invention. Many changes may be made to the present invention without departing from the spirit and scope of the present invention.

[0039] The embodiment of the present invention provides a lightweight tuned viscous mass damping spacer, which includes a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer connected by a spring unit. Figure 1 As shown, the ball screw-flywheel type tuned viscous mass damper includes an insulating sealing chamber 1, a screw 2, a positioning nut 3, a sealing ring 4, a rotating flywheel 5, a spring unit 6, a sliding bearing 7, a viscous fluid 8, a guide rail 9, a ball and a viscous damping chamber. In this embodiment, the ball screw-flywheel type tuned viscous mass damper is used to convert the axial movement of the screw driven by the displacement of the transmission line into high-speed rotational motion of the rotating flywheel when the transmission line experiences de-icing jump vibration. The viscous fluid in the viscous damping chamber generates shear resistance due to the rotation of the rotating flywheel, forming a damping force in the opposite direction of the de-icing jump vibration of the transmission line. The damping force dissipates the input energy caused by the transmission line vibration, offsets the vertical vibration energy of the transmission line caused by de-icing jump, and thus suppresses the de-icing jump height and accelerates vibration attenuation.

[0040] In some embodiments, the composite interphase spacer spans the upper and lower phase transmission conductors and is installed at the sag of the upper and lower phase transmission conductors. The ball screw-flywheel type tuned viscous mass damper is suspended between the lower phase transmission conductor and the composite interphase spacer through a spring unit, thereby forming a new type of tuned viscous mass damping spacer that has good electrical insulation performance and can effectively suppress the ice shedding and jumping of the transmission conductor. In the ball screw-flywheel type tuned viscous mass damper, the rotating flywheel is rigidly connected to the end of the screw by mechanical fixing to form a stable rotating system. The rotating flywheel serves as an inertial mass amplification system for cooperating with the viscous fluid in the viscous damping tank to dissipate energy and reduce vibration; the ball is slidably connected between the screw and the viscous damping tank. The other end of the screw rod forms a sliding fit with the guide rail in the viscous damping chamber through the ball. The guide rail provides a guiding function for the screw rod, completing the coupling of axial movement and rotational motion. The viscous damping chamber is filled with viscous fluid, and a damping effect is generated through the rotational motion of the rotating flywheel and the shear action of the viscous fluid. Specifically, when the transmission line jumps due to ice shedding, the vertical displacement of the transmission line drives the screw rod to generate axial movement, which is converted into high-speed rotational motion of the rotating flywheel through the sliding fit of the ball and the guide rail. The rotational kinetic energy is transmitted to the guide rail through the ball and generates a damping effect in the viscous damping chamber. The coupling of rotational kinetic energy and viscous damping is used to consume vibration energy, that is, the coupling effect of rotational kinetic energy and viscous damping is used to provide additional damping for the spacer rod.

[0041] At the same time, the composite interphase spacer is used to limit the asymmetric displacement of the transmission conductors after de-icing jump by rigidly connecting the upper and lower phase transmission conductors, thereby preventing electrical flashover caused by too small an air gap between the conductors, and transmitting the damping force generated by the ball screw-flywheel type tuned viscous mass damper to the transmission conductor through the spring unit, so that the damping effect of the ball screw-flywheel type tuned viscous mass damper directly acts on the transmission conductor, forming a dynamic coupling between the damping effect and the vibration of the transmission conductor, and synergistically suppressing the de-icing jump vibration. In this embodiment, the composite interphase spacer serves as a supporting structure for the transmission conductor, and is used to maintain the spacing between the transmission conductors. At the same time, the composite interphase spacer is made of an insulating material (such as a glass fiber reinforced composite material), and the insulating material is used to prevent short circuits or leakage between the transmission conductors.

[0042] In one embodiment, Figure 2 As shown, an embodiment of the present invention provides a method for determining optimal parameters of a lightweight tuned viscous mass damping spacer, which is applied to the above-mentioned lightweight tuned viscous mass damping spacer. The optimal parameter determination method includes:

[0043] S1. Based on the design drawings of the transmission tower-line system, establish a finite element calculation model of the conductor, perform modal vibration analysis on the finite element calculation model of the conductor, and obtain the first-order modal parameters of the conductor.

[0044] This embodiment first obtains design drawings of the transmission tower-line system. The design drawings of the transmission tower-line system may include information such as the layout of the transmission conductors, the geometric parameters of the transmission conductors, the material properties of the conductors, and the connection method between the conductors and the towers and spacers. Then, based on the design drawings of the transmission tower-line system, a finite element analysis method such as ANSYS is used to establish a three-dimensional finite element model of the transmission conductors to obtain a finite element calculation model of the conductors. Since the first-order mode generally has a significant impact on the dynamic response of the transmission conductors, this embodiment may use a modal analysis method to perform a modal solution on the conductor finite element calculation model to obtain the first-order modal parameters of the conductors. The modal analysis method may include a modal matrix iteration method or a subspace iteration method. The first-order modal parameters may include parameters such as the first-order modal mass, the first-order modal stiffness, the first-order modal damping ratio, and the first-order modal frequency.

[0045] S2. Perform an uncontrolled ice shedding jump response analysis based on the first-order modal parameters to determine a target jump height ratio of the conductor when it jumps due to ice shedding.

[0046] Specifically, this embodiment extracts the first-order modal parameters of the transmission conductor from an established conductor finite element calculation model. Based on the climatic conditions and historical icing data of the area where the conductor is located in an actual transmission tower-line system, the conductor's ice thickness and deicing rate are determined. The conductor's initial icing state and deicing process are set based on the ice thickness and deicing rate. The equivalent distributed load corresponding to the ice thickness, the deicing rate, and the conductor's first-order modal parameters are input into the conductor finite element calculation model to simulate the conductor's deicing jump process. An ice load is applied to the conductor surface to simulate a static icing state. A transient deicing load is applied using a transient dynamic response analysis method. An deicing jump response analysis is performed on the conductor finite element calculation model to obtain response analysis data for the conductor under deicing. The response analysis data may include displacement, velocity, acceleration, and other data. Furthermore, based on the electrical insulation clearance requirements of the transmission line and the response analysis data under an uncontrolled state, a target jump height ratio is determined for the conductor during deicing jump. This target jump height ratio represents the degree to which the conductor jump height is reduced relative to the uncontrolled state under the action of a ball screw-flywheel tuned viscous mass damper.

[0047] S3. Based on the target jump height ratio, the pole configuration method is used to optimize the parameters of the ball screw-flywheel type tuned viscous mass damper to obtain the optimal parameter configuration scheme for suppressing ice shedding jump; the optimal parameter configuration scheme includes the optimal stiffness ratio, the optimal damping ratio, and the optimal inertia-to-mass ratio.

[0048] In some embodiments, the step of optimizing the parameters of the ball screw-flywheel tuned viscous mass damper using a pole placement method based on the target jump height ratio to obtain an optimal parameter placement solution for suppressing ice shedding jumps includes:

[0049] A conductor-damper spacer coupled dynamic model is constructed, which includes a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer. The governing equations of the deicing jump motion of the conductor-damper spacer coupled dynamic model are determined based on the first-order modal parameters of the conductor.

[0050] Performing Laplace transform on the de-icing jump motion control equation to obtain the conductor displacement frequency domain transfer function;

[0051] Performing eigenvalue analysis on the conductor displacement frequency domain transfer function to obtain a real part of the eigenvalue, and defining a vibration attenuation rate based on the real part of the eigenvalue;

[0052] Under the constraint that the actual jump height ratio is no greater than the target jump height ratio, the optimal stiffness ratio, optimal damping ratio, and optimal inertia-to-mass ratio of the ball screw-flywheel tuned viscous mass damper are solved by the pole placement method with maximizing the vibration attenuation rate as the optimization goal.

[0053] Specifically, this embodiment establishes a conductor-damping spacer coupling dynamic model including a ball screw-flywheel type tuned viscous mass damper (TVMD) and a composite interphase spacer. The conductor-damping spacer coupling dynamic model should consider the connection relationship of each structure in the above-mentioned lightweight tuned viscous mass damping spacer, such as Figure 3 As shown in the figure, based on the first-order modal parameters of the conductor and the initial physical parameters of the ball screw-flywheel type tuned viscous mass damper, the control equation of the conductor's ice shedding jump motion in the conductor-damping spacer coupling dynamic model is derived. The specific control equation of the ice shedding jump motion is:

[0054]

[0055] Where m l is the first-order modal mass of the lower-phase transmission conductor; is the second-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; c l is the damping coefficient of the upper phase conductor; k is the first-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; l is the first-order modal stiffness of the lower phase transmission conductor; u l is the first-order modal displacement of the lower-phase transmission conductor; k f is the stiffness of the upper spacer; u u is the first-order modal displacement of the upper phase transmission conductor; k tis the stiffness of the ball screw-flywheel type tuned viscous mass damper; u t is the vertical displacement of the ball screw-flywheel type tuned viscous mass damper; F s is the impact load; m t is the inertia coefficient of the ball screw-flywheel type tuned viscous mass damper; is the second-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; c t is the damping coefficient of the ball screw-flywheel type tuned viscous mass damper; is the first-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; m u is the first-order modal mass of the upper phase transmission conductor; is the second-order derivative of the first-order modal displacement of the upper-phase transmission conductor with respect to time; c u is the damping coefficient of the lower phase transmission line; k is the first-order derivative of the first-order modal displacement of the upper phase transmission line with respect to time; u is the first-order modal stiffness of the upper phase transmission line.

[0056] At the same time, this embodiment introduces the following conductor parameters and dimensionless parameters of TVMD, which are specifically expressed as follows:

[0057]

[0058] Where ω is the natural circular frequency of the lower phase conductor; ζ0 is the natural damping ratio of the lower phase conductor; κ s is the stiffness ratio of the upper phase conductor to the lower phase conductor; μ s is the mass ratio of the upper phase conductor to the lower phase conductor; κ f is the stiffness ratio of the spacer relative to the lower phase conductor; ζ is the damping ratio of the TVMD (tuned viscous mass damper) relative to the lower phase conductor; κ is the stiffness ratio of the TVMD relative to the lower phase conductor; μ is the inertia-mass ratio of the TVMD relative to the lower phase conductor; b is the inertia coefficient of the TVMD, Figure 3 In the figure, L is the span between the two towers.

[0059] In this embodiment, based on the above-mentioned conductor parameters and dimensionless parameters of TVMD, the de-icing jump motion control equation is rewritten into the following form. The following is the de-icing jump motion control equation:

[0060]

[0061] Where, f s is the normalized rectangular short-time impact load.

[0062] Then, in order to analyze the dynamic characteristics of the system in the frequency domain, this embodiment performs Laplace transform on the de-icing jump motion control rewriting equation. The frequency domain de-icing jump motion control equation is obtained through Laplace transform. The frequency domain de-icing jump motion control equation is specifically expressed as:

[0063]

[0064] Where s is a complex frequency variable, where s = iΩ; Ω is the excitation frequency; i is a complex unit; U l is the Laplace transform of the first-order modal displacement of the lower-phase transmission conductor; U u is the Laplace transform of the first-order modal displacement of the upper phase transmission line; U t is the Laplace transform of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper; Γ s is the Laplace transform of the normalized rectangular short-duration impact load.

[0065] In this embodiment, by solving the frequency domain ice shedding jump motion control equation, the vertical displacement frequency response function (FRF) of the two conductors can be obtained, namely:

[0066]

[0067] Where, is the vertical displacement frequency response function of the lower phase conductor, which is used to describe the frequency domain relationship between the displacement of the lower phase conductor and the load; is the vertical displacement frequency response function of the upper phase conductor, which is used to describe the frequency domain relationship between the upper phase conductor displacement and load.

[0068] Because the load on conductors during ice shedding typically exhibits a strong short-term impact effect, the most unfavorable vibration response of the conductors is the displacement peak within a short period of time. To effectively control this impulse-type vibration response, this embodiment can configure the transfer function poles on the complex plane so that the impulse response in the time domain achieves the "maximized stability" effect with the fastest vibration attenuation. When the mechanical parameters of the upper and lower phase conductors are identical, the frequency domain responses of the upper and lower phase conductors are almost identical due to the installation of rigid spacers. Therefore, to simplify the derivation of formulas, this embodiment simplifies the two-phase conductors of the transmission conductor-novel tuned viscous mass damping spacer system into the lower phase conductor subjected to the impact load, that is, simplifying the three-degree-of-freedom system into a two-degree-of-freedom system (lower phase conductor-TVMD). In this simplified system, this embodiment uses the conductor displacement frequency domain transfer function HU to represent the conductor displacement transfer function of the lower phase conductor as an example. The specific form is:

[0069]

[0070] Where H Uis the frequency domain transfer function of the lower phase conductor displacement in a 2-DOF system (lower phase conductor-TVMD).

[0071] At the same time, in order to determine the frequency domain transfer function H of the wire displacement U (s). In this embodiment, the characteristic value of the wire displacement frequency domain transfer function is analyzed by the characteristic equation corresponding to the wire displacement frequency domain transfer function to obtain its characteristic value. The real part of the characteristic value reflects the attenuation characteristics of the system response, and the imaginary part is related to the vibration frequency. The characteristic equation corresponding to the wire displacement frequency domain transfer function is specifically:

[0072] δ4λ 4 +δ3λ 3 +δ2λ 2 +δ1λ+δ0=0

[0073] Where, δ j By the transfer function H U (s) is the real part coefficient determined by the characteristic equation, and the value range of j is 0 to 4; λ is the frequency domain transfer function of the conductor displacement H U The eigenvalue of (s) reflects the attenuation characteristics of the system response.

[0074] Real coefficient δ of the lower phase conductor-TVMD system j for:

[0075] δ4=μ, δ3=2ζ, δ2=k+μ+κμ, δ1=2ζ(1+κ), δ0=κ

[0076] This embodiment analyzes the eigenvalues ​​of the frequency domain transfer function of the conductor displacement and defines the vibration attenuation rate based on the real part of the eigenvalue. Considering the stability condition of the lower-phase conductor-TVMD system, that is, the real part of the system eigenvalue is negative, which generally reflects the attenuation trend of the structural response, this embodiment defines the vibration attenuation rate as the inverse of the maximum real part of the system eigenvalue. The larger the vibration attenuation rate, the faster the vibration attenuation of the system after the ice shedding jump and the better the stability. The specific expression of the vibration attenuation rate is:

[0077] Λ=-max(Re(λ j ))

[0078] Where Λ is the attenuation rate, which is defined as the inverse of the maximum real part of the system eigenvalue, reflecting the attenuation rate of the system response; λ j is the conductor displacement frequency domain transfer function H U The j-th eigenvalue of (s).

[0079] In this embodiment, the actual jump height ratio at the conductor sag is calculated based on the ratio of the maximum vertical displacement at the sag of the lower phase transmission conductor after vibration reduction to the vertical displacement at the sag of the lower phase transmission conductor before vibration reduction. To optimize the design parameters of the TVMD, this embodiment introduces the jump height ratio at the conductor sag as a constraint:

[0080]

[0081] Where, γ is the jump height ratio at the conductor sag; is the vertical displacement of the lower phase conductor sag before vibration reduction.

[0082] Combined with the jump height ratio constraint at the conductor sag, the optimization problem for the vibration attenuation rate in this embodiment can be expressed as:

[0083]

[0084] Where, l is the lower bound of the optimization variable; v is the optimization variable; υ u is the upper bound of the optimization variable; the superscript T is the transpose symbol; to maximize is the optimization goal, which represents the objective function to be maximized; for given represents the given parameters or conditions; and subject to represents the constraints in the optimization problem.

[0085] When the eigenvalues ​​of the system are in the form of a double complex conjugate pair, that is, λ1 = λ3 = a + bi and λ2 = λ4 = λ′1 = λ′3 = a + bi, the above optimization goal can be met. In this embodiment, the assumed complex eigenvalues ​​are substituted into the characteristic equation corresponding to the frequency domain transfer function to obtain the rearranged characteristic polynomial in the characteristic equation corresponding to the frequency domain transfer function:

[0086] λ 4 -4aλ 3 +(6a 2 +2b 2 )λ 2 +(-4a 3 -4ab 2 )λ+(a 4 +2a 2 b 2 +b 4 )=0

[0087] Where a is the real part of the complex eigenvalue, which represents the attenuation rate of the system response; b is the imaginary part of the complex eigenvalue, which represents the vibration frequency of the system response; λ1, λ2, λ3, and λ4 are the eigenvalues ​​of the transfer function; λ′1 is the conjugate complex number of the eigenvalue λ1 of the transfer function; and λ′3 is the conjugate complex number of the eigenvalue λ3 of the transfer function.

[0088] like Figure 4 As shown, when the actual jump height ratio is not greater than the target jump height ratio γ t Under the constraint condition of , this embodiment takes maximizing the vibration attenuation rate as the optimization goal and uses the pole placement method to place the desired closed-loop pole (i.e., the pole with the largest negative real part) on the eigenvalue of the transfer function, thereby solving the optimal stiffness ratio, optimal damping ratio, and optimal inertia-mass ratio of the TVMD. Figure 4 In, γ opt is the optimal jump height ratio obtained after optimization, which means that under a given target jump height ratio γ t Under the above conditions, the wire jump height ratio is obtained by optimizing the pole placement method. The pole placement method can ensure that the system has the desired dynamic performance in the time domain. If the characteristic equation corresponding to the frequency domain transfer function and the coefficients of the rearranged characteristic polynomial remain unchanged, the calculation formula of the optimal parameter configuration scheme based on the pole placement is:

[0089]

[0090] Where μ opt is the optimal inertia-mass ratio of TVMD; ζ opt is the optimal damping ratio of TVMD.

[0091] S4. Determine the actual physical parameters of the ball screw-flywheel type tuned viscous mass damper based on the optimal inertia-mass ratio, and input the actual physical parameters into a pre-established wire-damping spacer coupling dynamic model including the ball screw-flywheel type tuned viscous mass damper and the composite phase spacer.

[0092] S5. The shedding jump response is analyzed under controlled and uncontrolled conditions using the conductor-damper spacer coupling dynamic model to obtain the shedding jump suppression results.

[0093] S6. When the de-icing jump suppression result meets the preset performance index of the conductor, output the optimal parameter configuration solution.

[0094] In this embodiment, the actual physical parameters of the TVMD are determined based on the optimal inertia-mass ratio and the physical relationship between the ball screw lead, the equivalent radius of the rotating flywheel, and the rotational damping coefficient. The actual physical parameters include data such as the equivalent radius of the rotating flywheel, the physical mass of the rotating flywheel, the screw lead, and the rotational damping coefficient of the viscous material. The calculation formula for the actual physical parameters is:

[0095]

[0096] Where B is the inertia coefficient; r f is the equivalent radius of the rotating flywheel; l b is the lead of the screw; m tis the physical mass of the rotating flywheel; c r is the rotational damping coefficient.

[0097] In this embodiment, actual physical parameters are input into a coupled dynamics model, and the coupled dynamics model is used to analyze the deicing jump response under controlled and uncontrolled conditions, respectively. The actual jump height ratio and vibration attenuation rate are calculated. If the actual jump height ratio and the attenuation rate meet the requirements, the optimal parameter configuration scheme is output; if not, the target jump height ratio is adjusted and the optimization is repeated in step S3 until the preset performance indicators are met. Finally, the optimal parameter configuration scheme for the TVMD adapted to the transmission line is output. When analyzing the sag displacement response of the conductor in the uncontrolled state and when only rigid undamped spacers are installed, this embodiment specifically considers the deicing of the lower phase conductor. The time course of the deicing jump response is shown as follows: Figure 5 As shown, in order to more intuitively compare the responses under different conditions, this embodiment provides example data of normalized response of conductor sag in the state of no control and only installation of spacer bars as shown in Table 1. Table 1 is as follows:

[0098] Table 1

[0099]

[0100] As can be seen from Table 1, after the spacer is installed in this embodiment, the de-icing jump height ratio of the lower phase conductor is reduced to 0.515. In order to more effectively suppress the transient de-icing jump response of the conductor, this embodiment presets a target jump height ratio of 0.05 for installing a tuned viscous mass damper (TVMD). Combined with the calculation formula for the optimal parameter configuration solution, the optimal TVMD parameters shown in Table 2 can be calculated. Table 2 is as follows:

[0101] Table 2

[0102]

[0103] In this embodiment, the mass magnification factor is considered to be 200, and the physical mass of the TVMD flywheel can be calculated to be 2.40 kg. If the equivalent radius of the flywheel is r f If it is determined to be 50mm, the lead of the ball screw can be calculated to be 15.71mm. In addition, the rotation damping coefficient c of the TVMD is r Expressed as 0.0229N / (rad / s), in order to verify the effect of TVMD in suppressing ice shedding jump, this embodiment compares and analyzes the sag displacement response of the conductor in the uncontrolled state and the installation of spacer-TVMD. Figure 6The time-history curve of the de-icing jump response is presented. By comparing the response curves under different conditions, the effectiveness of the TVMD in practical applications can be evaluated. In this embodiment, a ball screw is used to drive a rotating flywheel to rotate at high speed, thereby generating a significant damping force. This not only effectively suppresses the de-icing jump phenomenon of the transmission line, but also can amplify the apparent mass of the TVMD to thousands of times the actual physical mass of the flywheel. This feature greatly promotes the lightweighting process of the device. In terms of optimal parameter design, this embodiment uses the pole configuration method as the theoretical basis to determine the optimal parameters of the new tuned viscous mass damping spacer. By flexibly adjusting the physical mass of the flywheel, the equivalent radius of the flywheel, and the lead of the ball screw, the precise design of the rotational damping of any TVMD can be achieved. This design strategy not only significantly reduces the de-icing jump height of the transmission line, but also effectively accelerates the stabilization speed of the transmission line vibration after de-icing, thereby comprehensively improving the safety and stability of the power system.

[0104] For the specific definition of the method for determining the optimal parameters of a lightweight tuned viscous mass damping spacer, please refer to the above-mentioned definition of a lightweight tuned viscous mass damping spacer, which will not be repeated here. A person of ordinary skill in the art will realize that the various modules and steps described in conjunction with the embodiments disclosed in this application can be implemented in hardware, software, or a combination of both. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application. It should be noted that the size of the serial number of each of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0105] An embodiment of the present invention provides a lightweight tuned viscous mass damping spacer and a method for determining its optimal parameters. The lightweight tuned viscous mass damping spacer includes a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer. The ball screw-flywheel type tuned viscous mass damper is used to convert the axial movement of the screw generated by the displacement of the transmission line into high-speed rotational motion of a rotating flywheel when the transmission line undergoes de-icing jump vibration, so that the viscous fluid in the viscous damping chamber generates shear resistance due to the rotation of the rotating flywheel, forming a damping force opposite to the vibration direction, and dissipating the input energy caused by the vibration of the transmission line through the damping force, thereby suppressing the de-icing jump height and accelerating the vibration attenuation. The composite interphase spacer is used to transmit the damping force generated by the ball screw-flywheel type tuned viscous mass damper to the transmission line through a spring unit, thereby collaboratively suppressing the de-icing jump vibration. Compared with the existing technology, this lightweight tuned viscous mass damping spacer effectively dissipates the vibration energy of the transmission line, suppresses the de-icing jump height and accelerates the vibration attenuation process through the synergistic effect of the ball screw-flywheel type tuned viscous mass damper connected by the spring unit and the composite phase spacer, thereby significantly improving the operating stability of the power system.

[0106] The above-described embodiments merely represent several preferred implementations of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art could make several improvements and substitutions without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be based on the scope of protection of the claims.

Claims

1. A lightweight tuned viscous mass damping spacer, characterized in that: include: A ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer connected by a spring unit; the ball screw-flywheel type tuned viscous mass damper includes a rotating flywheel, balls, a screw, a guide rail and a viscous damping chamber; The ball screw-flywheel type tuned viscous mass damper is used to convert the axial movement of the screw driven by the displacement of the transmission line into the high-speed rotational motion of the rotating flywheel when the transmission line experiences ice shedding jump vibration, so that the viscous fluid in the viscous damping chamber generates shear resistance due to the rotation of the rotating flywheel, forming a damping force opposite to the vibration direction. The damping force dissipates the input energy caused by the transmission line vibration, thereby suppressing the ice shedding jump height and accelerating the vibration attenuation; The composite interphase spacer is used to limit the asymmetric displacement of the transmission conductor after de-icing jump by rigidly connecting the upper and lower phase transmission conductors, and transmit the damping force generated by the ball screw-flywheel type tuned viscous mass damper to the transmission conductor through the spring unit, forming a dynamic coupling between the damping effect and the vibration of the transmission conductor, and synergistically suppressing the de-icing jump vibration.

2. A lightweight tuned viscous mass damping spacer according to claim 1, characterized in that: The composite interphase spacer spans the upper and lower phase transmission conductors and is installed at the sag of the upper and lower phase transmission conductors. The ball screw-flywheel type tuned viscous mass damper is suspended between the lower phase transmission conductor and the composite interphase spacer through a spring unit.

3. The lightweight tuned viscous mass damping spacer according to claim 1, characterized in that: The rotating flywheel is rigidly connected to the end of the screw rod by mechanical fixing to form a stable rotating system; The rotating flywheel serves as a mass amplification system of the inertia capacity, and is used to cooperate with the viscous fluid in the viscous damping chamber to perform energy consumption and vibration reduction.

4. The lightweight tuned viscous mass damping spacer according to claim 1, characterized in that: The ball is slidably connected between the screw and the viscous damping chamber, and the other end of the screw forms a sliding fit with the guide rail in the viscous damping chamber through the ball, completing the coupling of axial movement and rotational motion.

5. The lightweight tuned viscous mass damping spacer according to claim 1, characterized in that: The composite interphase spacer is made of insulating material, and the insulating material is used to prevent short circuit or leakage between transmission lines.

6. A method for determining optimal parameters of a lightweight tuned viscous mass damping spacer, characterized in that: The optimal parameter determination method includes: According to the design drawings of the transmission tower line system, a finite element calculation model of the conductor is established, and modal vibration analysis is performed on the finite element calculation model of the conductor to obtain the first-order modal parameters of the conductor; An uncontrolled ice shedding jump response analysis is performed based on the first-order modal parameters to determine a target jump height ratio of the conductor when ice shedding jumps; Based on the target jump height ratio, the pole placement method is used to optimize the parameters of the ball screw-flywheel type tuned viscous mass damper to obtain the optimal parameter configuration scheme for suppressing ice shedding jump; the optimal parameter configuration scheme includes the optimal stiffness ratio, the optimal damping ratio, and the optimal inertia-to-mass ratio; Determining actual physical parameters of the ball screw-flywheel type tuned viscous mass damper according to the optimal inertia-mass ratio, and inputting the actual physical parameters into a pre-established conductor-damper spacer coupling dynamic model including the ball screw-flywheel type tuned viscous mass damper and the composite interphase spacer; The shedding jump response is analyzed under controlled and uncontrolled conditions using the conductor-damper spacer coupling dynamic model, and the shedding jump suppression results are obtained. When the de-icing jump suppression results meet the preset performance indicators of the conductor, the optimal parameter configuration solution is output.

7. The method for determining optimal parameters of a lightweight tuned viscous mass damping spacer according to claim 6, characterized in that: The actual physical parameters include the equivalent radius of the rotating flywheel, the physical mass of the rotating flywheel, the lead of the screw and the rotational damping coefficient of the viscous material.

8. The method for determining optimal parameters of a lightweight tuned viscous mass damping spacer according to claim 6, wherein: The step of optimizing the parameters of the ball screw-flywheel type tuned viscous mass damper using a pole placement method according to the target jump height ratio to obtain an optimal parameter placement solution for suppressing ice shedding jumps comprises: A conductor-damper spacer coupled dynamic model is constructed, which includes a ball screw-flywheel type tuned viscous mass damper and a composite interphase spacer. The governing equations of the deicing jump motion of the conductor-damper spacer coupled dynamic model are determined based on the first-order modal parameters of the conductor. Performing Laplace transform on the de-icing jump motion control equation to obtain the conductor displacement frequency domain transfer function; Performing eigenvalue analysis on the conductor displacement frequency domain transfer function to obtain a real part of the eigenvalue, and defining a vibration attenuation rate based on the real part of the eigenvalue; Under the constraint that the actual jump height ratio is no greater than the target jump height ratio, the optimal stiffness ratio, optimal damping ratio, and optimal inertia-to-mass ratio of the ball screw-flywheel tuned viscous mass damper are solved by the pole placement method with maximizing the vibration attenuation rate as the optimization goal.

9. The method for determining optimal parameters of a lightweight tuned viscous mass damping spacer according to claim 8, wherein: The de-icing jump motion control equation is specifically: Where m l is the first-order modal mass of the lower-phase transmission conductor; is the second-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; c l is the damping coefficient of the upper phase conductor; k is the first-order derivative of the first-order modal displacement of the lower-phase transmission conductor with respect to time; l is the first-order modal stiffness of the lower phase transmission conductor; u l is the first-order modal displacement of the lower-phase transmission conductor; k f is the stiffness of the upper spacer; u u is the first-order modal displacement of the upper phase transmission conductor; k t is the stiffness of the ball screw-flywheel type tuned viscous mass damper; u t is the vertical displacement of the ball screw-flywheel type tuned viscous mass damper; F s is the impact load; m t is the inertia coefficient of the ball screw-flywheel type tuned viscous mass damper; is the second-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; c t is the damping coefficient of the ball screw-flywheel type tuned viscous mass damper; is the first-order derivative of the vertical displacement of the ball screw-flywheel type tuned viscous mass damper with respect to time; m u is the first-order modal mass of the upper phase transmission conductor; is the second-order derivative of the first-order modal displacement of the upper-phase transmission conductor with respect to time; c u is the damping coefficient of the lower phase transmission line; k is the first-order derivative of the first-order modal displacement of the upper phase transmission line with respect to time; u is the first-order modal stiffness of the upper phase transmission line.

10. The method for determining optimal parameters of a lightweight tuned viscous mass damping spacer according to claim 8, wherein: The actual jump height ratio at the conductor sag is calculated based on the ratio of the maximum vertical displacement at the sag of the lower phase transmission conductor after vibration reduction to the vertical displacement at the sag of the lower phase transmission conductor before vibration reduction.

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