Ground wire six-order anti-vibration device with broadband adaptability

Abstract

The invention belongs to the field of power transmission line anti-vibration, and particularly relates to a six-order anti-vibration device suitable for a ground wire, the device is fixed on the ground wire through a bolt by a wire clamp (1), three hollow cylinder structures (5, 6, 7) with two closed ends are connected through a connecting frame (4), two springs (for example, 8, 10) are arranged in each cylinder and are respectively connected with different counterweight columns, and the counterweight columns are connected with the three hollow cylinder structures (5, 6, 7). The balance weight column is filled with damping liquid to form a series mass-spring-damping system, and the six-order inherent frequency is achieved by adjusting the mass of the balance weight column and the spring rigidity. Compared with the prior art, by means of the six-order inherent frequency design, the problems that a traditional anti-vibration device is poor in frequency matching performance and low in energy consumption efficiency, and a steel strand is prone to fatigue fracture are solved, and the device has the wider-band vibration suppression capacity and higher stability. The device effectively suppresses aeolian vibration, reduces lead fatigue damage, remarkably prolongs the service life of the power transmission line, and is suitable for power transmission line vibration protection in a complex environment.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration dampers, and particularly to a novel sixth-order vibration damper and its method, which has a wider natural frequency distribution and higher vibration damping ability. Background Art

[0002] Aeolian vibration refers to the formation of a Karman vortex street that alternately sheds up and down on the leeward side of the wire under the action of a stable wind of about 0.5 - 7 m / s, resulting in an alternating aerodynamic force acting on the wire, which in turn causes a vertical vibration perpendicular to the incoming flow direction. When the frequency of the alternating force approaches a certain natural frequency of the wire, the vibration amplitude will increase significantly. This vibration is characterized by small amplitude and high frequency, and occurs frequently and lasts for a long time, up to several hours or even days. Aeolian vibration causes fatigue breakage of the wire at the installation fittings, especially at the suspension clamp, seriously threatening the safety and stability of the power grid system. To reduce the harm of aeolian vibration to the transmission line, vibration dampers are usually installed on the wire to suppress the vibration amplitude and extend the service life of the line.

[0003] Currently, the Stockbridge vibration damper is widely used. It suppresses vibrations in the range of 10 - 65 Hz through the damping performance of the steel strand. Its design is mainly based on the outer diameter of the wire and does not fully consider the frequency characteristics of aeolian vibration in different regions, resulting in limited vibration damping effect. In addition, during the long-term use of traditional vibration dampers, the steel strand is prone to fatigue fracture, leading to a decline in performance. Its damping performance is difficult to accurately measure and adjust, and it is difficult to optimize the design according to the line requirements, with a limited scope of application.

[0004] To address the above problems, the present invention proposes a novel sixth-order vibration damping device. This device is designed with six sets of mass-spring-damping systems, having six natural frequencies. By adjusting the mass of each counterweight column and selecting springs with different stiffnesses, it can suppress aeolian vibrations in the frequency bands below 10 Hz and above 65 Hz. Compared with traditional vibration damping devices, this device can prevent differential vibrations in different frequency bands, and at the same time has the characteristics of high energy consumption, high vibration damping efficiency, and long service life, providing a better solution for complex transmission lines. Summary of the Invention

[0005] The object of the present invention is to provide a sixth-order multi-frequency vibration damping device suitable for suppressing the aeolian vibration of wires. By setting multiple mass-spring-damping systems inside the device to meet the vibration requirements of different frequencies, it can effectively consume the kinetic energy generated by the wire vibration and reduce the vibration intensity. Compared with traditional vibration dampers, this vibration damping device has a wider frequency adaptability and higher vibration suppression efficiency, can adapt to the vibration characteristics under various wind speed conditions, and solves the problems of frequency range mismatch and fatigue damage existing in the prior art.

[0006] To achieve the above object, the present invention provides a sixth-order anti-vibration device based on a mass-spring-damping system, including a wire clamp, a cylinder, a spring, a counterweight column and damping liquid. The device is firmly installed on the transmission line conductor through its wire clamp. The device uses the damping force generated by the internal damping liquid and counterweight column to consume vibration energy and achieve the purpose of effectively suppressing vibration.

[0007] The wire clamp is used to fixedly install the cylinder on the conductor. The wire clamp and the cylinder are connected by bolts, ensuring the stability and anti-vibration performance of the device, so that it can remain firm under various wind conditions.

[0008] The cylinder structure is a closed cylinder at both ends and is filled with damping liquid inside. The damping liquid generates viscous damping on the movement of the counterweight column and absorbs the kinetic energy of the counterweight column, thereby reducing the impact of vibration on the conductor.

[0009] The damping liquid uses methyl silicone oil. Methyl silicone oil has high viscosity and thermal stability, and can maintain good damping effect within a wide temperature range, ensuring the stability of the anti-vibration device under different climate conditions.

[0010] The inside of the cylinder is completely sealed to ensure that the damping liquid will not leak. The sealed structure isolates the damping liquid from the outside air and water vapor, avoiding the volatilization and pollution of the damping liquid, and at the same time preventing the internal metal spring and counterweight column from rusting due to oxidation.

[0011] Two springs are arranged inside the cylinder, respectively connecting two counterweight columns. Among them, one end of a spring is fixedly connected to the lower end of the cylinder, and the other end is connected to the lower counterweight column; the other spring is connected between the upper counterweight column and the lower counterweight column. This design forms a series double mass-spring system, which can absorb and disperse vibration energy in a wider frequency range.

[0012] The spring and the counterweight column are installed axially inside the cylinder and can vibrate up and down with the vibration of the conductor, further enhancing the anti-vibration effect of the device.

[0013] The fixing method of the spring and the counterweight column adopts welding connection to ensure the stability and reliability of the structure, and avoid loosening or breaking caused by long-term vibration.

[0014] There is at least a 5mm gap between the counterweight column and the inner wall of the cylinder to ensure that the counterweight column can move freely inside the cylinder during vibration without direct contact with the inner wall of the cylinder, thereby avoiding wear and noise caused by metal friction.

[0015] The present invention also provides an optimized design scheme for multiple anti-vibration effects, that is, by adjusting the mass of different counterweight columns inside the cylinder and the stiffness of the spring, different natural frequencies are formed. This design enables the device to be adjusted according to the vibration characteristics of the specific conductor and more effectively suppress vibration.

[0016] The mass of the counterweight column can be selected according to the wire vibration frequency requirements, so as to achieve the best match with the wire vibration frequency range. Combinations of counterweight columns of different masses and springs form a multi-stage frequency resonance system, improving the frequency response range of the anti-vibration device.

[0017] The stiffness of the spring can be adjusted according to the climate characteristics of the installation area, so as to maintain the best anti-vibration effect under different wind speeds and wind pressures.

[0018] The counterweight column is made of high-density material to increase its mass. High-quality counterweight columns can enhance the inertial effect of the mass-spring-damping system and improve the energy dissipation ability under low-frequency vibration.

[0019] In order to improve the anti-fatigue performance of the device, the spring is made of high-strength and corrosion-resistant alloy material to prevent fatigue fracture caused by long-term vibration, while enhancing its antioxidant performance and extending the service life of the device.

[0020] The viscosity and capacity of the damping fluid in the device are strictly designed to ensure stable damping effect under various temperature conditions. The viscosity of the damping fluid can be optimized by adjusting the formula to adapt to the vibration requirements of different lines.

[0021] The six-order anti-vibration device has a compact structure and is easy to install. The wire clamp, cylinder, spring and counterweight column are fixed together by bolts to ensure that the device will not loosen or deform during transportation and installation.

[0022] All metal parts of the device are treated with surface plating to improve the anti-corrosion performance and ensure that the device can operate stably for a long time in an environment with high humidity.

[0023] The six-order anti-vibration device of the present invention can be installed without frequent maintenance after installation. The closed design of the damping fluid avoids the risk of leakage and can maintain a stable anti-vibration effect for a long time.

[0024] The six-order anti-vibration device of the present invention realizes the efficient suppression of aeolian vibration through the design of the mass-spring-damping system. The device has a simple structure, is easy to install, has a wide anti-vibration frequency band, effectively reduces wire vibration, and has good application prospects. Description of the Drawings

[0025] The present invention will be further described below with reference to the drawings and embodiments.

[0026] Figure 1 is a three-dimensional external structure diagram of the present invention;

[0027] Figure 2 is a perspective view of the overall structure of the present invention;

[0028] Figure 3 Explosion diagram of the device of the present invention;

[0029] Figure 4 Top view of the overall external structure of the present invention;

[0030] Figure 5 Structural diagram of the cylinder - mass - spring - damper system of the present invention.

[0031] In the figure: 1. Line clamp, 2. Hexagon head bolt, 3. Locknut, 4. Connecting frame, 5. First cylinder, 6. Second cylinder, 7. Third cylinder, 8. First spring, 9. First counterweight column, 10. Second spring, 11. Second counterweight column, 12. Third spring, 13. Third counterweight column, 14. Fourth spring, 15. Fourth counterweight column, 16. Fifth spring, 17. Fifth counterweight column, 18. Sixth spring, 19. Sixth counterweight column. Detailed implementation manners

[0032] To better understand the present invention, the content of the present invention will be further described below in conjunction with the accompanying drawings of the specification and examples.

[0033] 1. Vibration prevention principle:

[0034] The six - order vibration prevention device of the present invention aims to suppress the vibration of transmission lines under the action of gentle breeze. The device realizes multiple vibration suppression effects at different vibration frequencies through the built - in mass - spring - damper system. The device relies on different combinations of damping liquid and multiple counterweight columns to dissipate the vibration energy of the wire, prevent the further increase of the vibration amplitude of the wire, and ensure the stability of the line. The damping liquid in the cylinder provides viscous damping when the counterweight column vibrates, and gradually converts the vibration energy into heat energy for dissipation. In addition, through the double mass - spring system in the cylinder, the device works at six natural frequencies, forming a wide - band vibration suppression bandwidth.

[0035] The vibration prevention device of the present invention adopts a symmetric layout, and the center of mass of the overall system is located at the center. The line clamp and the connecting frame of the vibration preventer are used as the fixed ends, and the vibrations in the three cylinders do not interfere with each other. Taking the connecting frame as the boundary, the vibration preventer is divided into three independent subsystems. Taking the mass - spring - damper system of each cylinder as the research object, its motion can be simplified into a two - degree - of - freedom vibration system in series.

[0036] The masses of the two counterweight columns in a single cylinder are m1 and m2 respectively, the stiffness coefficients of the two springs are k1 and k2 respectively, and the viscous damping coefficient is c. When vibrating under gentle breeze, the dynamic equation in a single cylinder is as follows:

[0037]

[0038] Where u, and They are the displacement, velocity, and acceleration of the counterweight column relative to the cylinder, respectively; is the acceleration of the cylinder in the vertical direction, which is equal to the acceleration at the wire clamp; the mass matrix M, stiffness matrix K, and damping matrix C are respectively:

[0039]

[0040] Considering the undamped free vibration corresponding to the shock absorber subsystem, so c = 0, At this time

[0041]

[0042] Then its frequency equation is:

[0043] |K - ω 2 M| = 0 (4)

[0044] Substitute the mass matrix M and stiffness matrix K to get:

[0045]

[0046] The roots solved are:

[0047]

[0048] At this time, the characteristic equation has two positive real roots and So there are two frequencies ω1 and ω2, which are uniquely determined by the mass of the counterweight column and the spring stiffness of this subsystem.

[0049] 2. Device assembly:

[0050] This shock absorber device includes a wire clamp 1, a hexagon head bolt 2, a fastening nut 3, a connecting frame 4, a first cylinder 5, a second cylinder 6, a third cylinder 7, damping liquid 11, and multiple groups of springs and counterweight columns (as Figure 1 , Figure 2 shown). The wire clamp 1 is used to firmly install the shock absorber device on the transmission line conductor. The wire clamp 1 and the connecting frame 4 are connected by bolts 2 and fastening nuts 3 to ensure that the device remains stable under high wind conditions. The cylinders 5, 6, and 7 are all filled with damping liquid 11 to provide viscous damping and slow down the vibration effect. The damping liquid 11 uses methyl silicone oil, which has high viscosity and thermal stability, can adapt to various temperature conditions, and effectively isolates the outside air and moisture to avoid corrosion of the internal metal components.

[0051] Two springs and multiple counterweight columns are installed in each cylinder to form a series mass-spring system (as Figure 4As shown. For example, a first spring 8 and a second spring 10 are installed inside the first cylinder 5, connecting the first counterweight column 9 and the second counterweight column 12 respectively. One end of the first spring 8 is fixed to the bottom of the cylinder, and the other end is connected to the first counterweight column 9; the second spring 10 is connected between the first counterweight column 9 and the second counterweight column 12, forming a double-mass system in series.

[0052] 3. Technical guarantee:

[0053] To ensure that the device can adapt to the design requirements of different lines, the connection between the wire clamp 1 and the wire adopts a hinge structure, which can better adapt to the bending and swinging of the line. In addition, the masses of different springs and counterweight columns in the device are optimized through calculation to provide a sixth-order natural frequency, ensuring that the device can work effectively under low, medium, and high-frequency vibration conditions and avoiding the problem of insufficient frequency band range of traditional vibration dampers.

[0054] The counterweight columns 9, 12, 14, etc. are all made of high-density materials to increase their mass and enhance the vibration suppression effect of the device under low-frequency vibration. The springs are made of high-strength corrosion-resistant materials and are welded between each counterweight column and the cylinder wall to ensure structural stability during long-term use and prevent fatigue fracture.

[0055] To better adapt to different environmental conditions, the viscosity and capacity of the damping liquid are strictly designed to ensure that the device can maintain a stable vibration suppression effect under various temperature conditions. The viscosity can be adjusted according to the installation environment and the specific vibration frequency requirements of the line to further optimize the vibration suppression performance.

[0056] 4. Working principle: When the wire is subjected to aeolian vibration, the mass-spring-damping system inside the cylinder vibrates accordingly, and the damping liquid in the system provides viscous damping to dissipate the vibration energy. Springs with different lengths and stiffnesses and counterweight columns with different masses produce resonance effects at the sixth-order natural frequency, thereby consuming the vibration input energy.

[0057] The springs and counterweight columns are distributed along the axial direction of the cylinder. There is a gap of more than 5 mm between the counterweight column and the inner wall of the cylinder to ensure that the counterweight column does not directly contact the cylinder wall during vibration, so as to avoid wear and noise caused by friction and further improve the durability of the device.

[0058] The sixth-order vibration suppression device of the present invention has the following characteristics:

[0059] (1) Adopting a multi-stage vibration suppression structure with a sixth-order natural frequency distribution, it can suppress vibrations from low frequency to high frequency;

[0060] (2) The combined design of the damping liquid and multiple counterweight columns ensures the high energy consumption effect of the device;

[0061] (3) Strong durability, excellent anti-corrosion performance, suitable for various climate environments.

Claims

1. A sixth-order anti-vibration device applicable to transmission lines, characterized in that, The device is hung on a transmission wire and includes: a wire clamp (1), a plurality of closed cylinders (5, 6, 7), springs (8, 10, 13, etc.), counterweight columns (9, 12, 14, etc.) and damping fluid (11); the cylinders (5, 6, 7) are hollow structures with closed ends, filled with damping fluid (11) inside, and two springs and corresponding counterweight columns are arranged in each cylinder to form a series mass-spring system, realizing a six-order natural frequency distribution; the damping fluid (11) is used to absorb vibration energy and reduce the vibration amplitude of the wire through viscous damping, avoiding fatigue damage of the wire.

2. The sixth-order vibration isolation device according to claim 1, characterized in that The damping fluid (11) uses methyl silicone oil, the springs use corrosion-resistant alloy materials, and the counterweight columns are made of high-density materials; there is at least a 5-mm gap between the counterweight columns and the inner wall of the cylinder to ensure that the counterweight columns move freely during vibration, avoiding contact with the inner wall of the cylinder to cause friction and noise, and improving the stability and durability of the device.

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