10kv overhead insulated conductor phase-to-phase spacer and method for analyzing its anti-dancing effect

Abstract

The present application relates to 10kV overhead insulated conductor phase spacing rod and its anti-dancing effect analysis method, a kind of phase spacing rod suitable for 10kV double return vertical arrangement overhead line is designed, and the anti-dancing effect of the spacing rod is analyzed, so as to determine phase spacing rod anti-dancing scheme.A kind of phase spacing rod suitable for 10kV double return vertical arrangement overhead line and installation scheme are proposed, which provides a new dancing countermeasure for 10kV distribution network overhead line dancing, helps to prevent and control wire dancing, and makes up the blank of existing 10kV line phase spacing rod product structure.

Description

Technical Field

[0001] This invention belongs to the field of power distribution analysis technology, and in particular to the analysis method of phase-to-phase spacers for 10kV overhead insulated conductors and their anti-galling effect. Background Technology

[0002] With rapid economic development, people's demand for electricity continues to increase, leading to the more widespread construction of overhead power lines and their ever-expanding coverage.

[0003] While conductor galloping is not the same as a line fault, it can easily cause mechanical and electrical faults in the line, such as damage or detachment of hardware, breakage of insulation layers in insulated conductors or broken strands in bare conductors, damage or even collapse of towers, and flashover short circuits. Currently, for both high-voltage transmission lines and 10kV overhead distribution lines, the main conductor galloping prevention measures can be divided into three categories: first, gallop avoidance, which involves avoiding icing areas and line routes prone to galloping during the planning and design phase, taking into account adverse weather and terrain conditions; second, gallop resistance, which involves improving the line's resistance to galloping from a mechanical and electrical safety perspective, ensuring that no fault occurs even if galloping occurs; and third, gallop suppression, which involves changing and adjusting conductor parameters, installing various anti-galloping devices, and implementing anti-galloping measures to fundamentally suppress the occurrence of galloping.

[0004] Existing anti-galloping devices mainly include disturbance anti-galloping devices, detuning pendulums, centralized vibration dampers, phase-to-phase spacers, double-pendulum anti-galloping devices, integral eccentric counterweights, and clamp-type rotating spacers. Evaluation and analysis of the anti-galloping effects of various provincial power grid companies show that, overall, different anti-galloping devices are effective against galloping, but each also has its limitations. To date, no single anti-galloping device is suitable for all types of line galloping. Furthermore, the aforementioned anti-galloping devices are designed for high-voltage transmission lines, which differs significantly from the actual conditions of 10kV distribution network overhead lines. Based on actual anti-galloping cases from Jilin, Inner Mongolia, and Hebei power grid companies, spacers have proven to be an effective anti-galloping measure. However, there are no spacer products on the market suitable for 10kV double-circuit vertically arranged lines. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and to propose a method for analyzing the anti-galling effect of 10kV overhead insulated conductor phase spacers. This provides a new galloping countermeasure for 10kV distribution network overhead lines and helps prevent and manage conductor galloping.

[0006] The technical problem solved by this invention is achieved through the following technical solution:

[0007] The 10kV overhead insulated conductor phase-to-phase spacer bar has the extension direction of the overhead insulated conductor as the transverse direction and the direction perpendicular to the extension direction of the overhead insulated conductor as the longitudinal direction. It includes several overhead insulated conductor connecting rods, which are connected by a first insulating connecting rod. The overhead insulated conductor connecting rods are arranged transversely, and different overhead insulated conductors are connected to each end of the overhead insulated conductor connecting rod.

[0008] Furthermore, the overhead insulated conductor connecting rod includes a connecting hardware, a second insulated connecting rod, and a wire clamp. The two longitudinal ends of the connecting hardware are respectively connected to the second insulated connecting rod, and the other end of the second insulated connecting rod is respectively connected to the wire clamp. At the same time, the second insulated connecting rod has a rubber skirt for support and insulation.

[0009] Furthermore, the clamp includes a rubber pad, a fastening mechanism, and a fixing clamp. The fastening mechanism controls the opening and closing of the fixing clamp for connecting overhead insulated wires. The fastening mechanism is connected to the second insulating connecting rod through the rubber pad.

[0010] Furthermore, the connecting fittings include cross-shaped connecting fittings and T-shaped connecting fittings. The horizontally arranged overhead insulated wire connecting rod located in the middle is connected to other overhead insulated wire connecting rods through the cross-shaped connecting fittings, and the horizontally arranged overhead insulated wire connecting rods located at both ends are connected to other overhead insulated wire connecting rods through the T-shaped connecting fittings.

[0011] A method for analyzing the anti-galling effect of phase-to-phase spacers on 10kV overhead insulated conductors includes the following steps:

[0012] Step 1: Establish a simulation model of a 10kV double-circuit vertically arranged line with spacers installed;

[0013] Step 2: Mesh the simulation model established in Step 1;

[0014] Step 3: Perform prestressed modal analysis on the simulation model generated by mesh generation in Step 2 and obtain the analysis results;

[0015] Step 4: Process the analysis results to obtain the anti-galloping effect of the phase spacers for overhead insulated conductors.

[0016] Moreover, the specific implementation method of step 1 is as follows: based on the actual structural parameters of the overhead insulated conductor, a three-dimensional finite element simulation model of a 10kV double-circuit vertically arranged overhead line with spacers installed is established, and the connection between each part in the model is set such that the contact surfaces neither separate nor slide relative to each other.

[0017] Moreover, the specific implementation method of step 2 is as follows: according to the actual parameters of different structures in the simulation model, different parts are divided into meshes with different roughness.

[0018] Furthermore, the specific implementation method of step 3 is as follows:

[0019]

[0020]

[0021] in, For the first i First natural vibration frequency, For the quality matrix, Here is the stiffness matrix. For the first i The eigenvectors of the modal shape.

[0022] Moreover, the specific implementation method of step 4 is as follows: based on the different modal shapes and modal frequencies of step 3, the anti-galling effect of the phase spacers of the 10kV double-circuit vertically arranged line is analyzed.

[0023] The advantages and positive effects of this invention are:

[0024] 1. This invention designs a phase-to-phase spacer suitable for 10kV double-circuit vertically arranged overhead lines and analyzes its anti-galling effect to determine an anti-galling scheme. It proposes a phase-to-phase spacer and installation scheme suitable for 10kV double-circuit vertically arranged overhead lines, providing a new countermeasure for 10kV distribution network overhead line galloping, contributing to the prevention and control of conductor galloping, and filling a gap in the existing 10kV line phase-to-phase spacer product structure.

[0025] 2. In the anti-galling effect analysis method, the present invention uses finite element simulation to conduct prestressed modal analysis on a 10kV double-circuit vertical overhead line with or without phase spacers. The modal shapes and modal frequencies of different modal orders of the model are obtained. The application effect of phase spacers is compared and analyzed, highlighting the role of phase spacers in the present invention.

[0026] 3. This invention utilizes a pre-stress model to establish the model and apply loads, effectively reducing the difficulty of building a physical model and minimizing accidental errors during data acquisition. Simultaneously, simulation allows for easier modification of experimental conditions and reduces the complexity of data processing. Attached Figure Description

[0027] Figure 1 This is a structural diagram of the phase-to-phase spacer bar for the double-circuit vertically arranged line of the present invention;

[0028] Figure 2 A schematic diagram of a double-circuit vertically arranged circuit with phase spacers added according to the present invention;

[0029] Figure 3Schematic diagram of the model grid division of the present invention;

[0030] Figure 4 It is the diagram of the first four modal shapes of the line before installing spacer dampers of the present invention;

[0031] Figure 5 It is the diagram of the first four modal shapes of the line after installing spacer dampers of the present invention. Description of the drawings:

[0033] 1 - clamp, 2 - second insulating connecting rod, 3 - first insulating connecting rod, 4 - T-shaped connecting fitting, 5 - cross-shaped connecting fitting, 6 - rubber pad, 7 - fastening mechanism, 8 - fixing clamp. Detailed implementation manners

[0034] The present invention will be further described in detail below with reference to the drawings.

[0035] The phase spacer damper for 10kV overhead insulated conductors has the extension direction of the overhead insulated conductors as the transverse direction and the direction perpendicular to the extension direction of the original overhead insulated conductors as the longitudinal direction, and includes a plurality of overhead insulated conductor connecting rods. The overhead insulated conductor connecting rods are connected by the first insulating connecting rod 3 to form a "king" shape. The overhead insulated conductor connecting rods are arranged horizontally, and both ends of the overhead insulated conductor connecting rods are respectively connected to different overhead insulated conductors.

[0036] As Figure 1 shown, the overhead insulated conductor connecting rod includes a connecting fitting, a second insulating connecting rod 2 and a clamp 1. The longitudinal ends of the connecting fitting are respectively connected to the second insulating connecting rods, and the other ends of the second insulating connecting rods are respectively connected to the clamps. The second insulating connecting rod and the connecting fitting are cast as a whole, and the second insulating connecting rod has rubber umbrella skirts for support and insulation.

[0037] The clamp includes a rubber pad 6, a fastening mechanism 7 and a fixing clamp 8. The fastening mechanism controls the opening and closing of the fixing clamp for connecting the overhead insulated conductors, and the fastening mechanism is connected to the second insulating connecting rod through the rubber pad.

[0038] The connecting fitting includes a cross-shaped connecting fitting 5 and a T-shaped connecting fitting 4. The horizontally arranged overhead insulated conductor connecting rods in the middle are connected to other overhead insulated conductor connecting rods through the cross-shaped connecting fitting, and the horizontally arranged overhead insulated conductor connecting rods at both ends are connected to other overhead insulated conductor connecting rods through the T-shaped connecting fitting.

[0039] A method for analyzing the anti-vibration effect of a phase spacer damper for 10kV overhead insulated conductors includes the following steps:

[0040] Step 1: Establish a simulation model of a 10kV double-circuit vertical arrangement line with spacer dampers installed.

[0041] Based on the actual structural parameters of the overhead insulated conductor, a three-dimensional finite element simulation model of a 10kV double-circuit vertically arranged overhead line with spacers installed was established. At the same time, the connection between each part in the model was set as bonded (i.e., the contact surfaces neither separate nor slide relative to each other).

[0042] Step 2: Mesh the simulation model established in Step 1.

[0043] Based on the actual parameters of different structures in the simulation model, different parts are divided into meshes with different roughness.

[0044] Step 3: Perform prestressed modal analysis on the simulation model generated by mesh generation in Step 2 and obtain the analysis results.

[0045] Considering that the pole-wire system is constantly under the influence of gravity during normal operation, this invention employs a prestressed modal analysis method to analyze the natural frequencies and modal shapes of the model. Before performing prestressed modal analysis, a static analysis must be conducted, and the results of the static analysis must be imported into the modal analysis settings.

[0046] Modal analysis is a method for analyzing the natural frequencies and modal shapes of a structure. It assumes the following in its analysis: 1. The structural stiffness matrix and mass matrix do not change; 2. Damping effects are not considered unless a damping characteristic solution method is specified; 3. There are no time-varying loads in the structure.

[0047] Therefore, in an undamped system, the structural vibration equation is obtained:

[0048]

[0049] in, This is the quality matrix; Here is the stiffness matrix; The nodal acceleration vector; Let be the nodal displacement matrix.

[0050] The stiffness matrix can include the additional stiffness introduced by the prestressing effect. For a linear system, free vibration satisfies the following equation:

[0051]

[0052] in, For the first i Eigenvectors of the first modal shape; For the first i The natural vibration frequency; t For time.

[0053] Based on the structural vibration equation and the free vibration equation, we obtain:

[0054]

[0055] The vibration characteristic equation of the structure is then obtained as follows:

[0056]

[0057] The first [equation] can be obtained from the vibration characteristic equation. i First natural vibration frequency Therefore, the first one can be calculated. i eigenvectors of modal shapes .

[0058] Step 4: Process the analysis results to obtain the anti-galloping effect of the phase spacers for overhead insulated conductors.

[0059] The conductor galloping process is a complex process of superposition of various natural frequencies, with the lower-order mode shapes and natural frequencies playing a major role. Therefore, by analyzing the low-order mode shapes and frequencies, the anti-galloping effect of the spacers can be analyzed to a certain extent. Based on the different order mode shapes and frequencies obtained in step 3, the anti-galloping effect of the spacers between phases of a 10kV double-circuit vertically arranged line can be further analyzed.

[0060] Based on the above-mentioned analysis method of the phase-to-phase spacer bar of 10kV overhead insulated conductor and its anti-galling effect, a simulation calculation is conducted to illustrate the experimental effect of the present invention:

[0061] For example Figure 2 As shown, taking the Z2-3 double-circuit straight cement pole (compact type) as an example, two three-dimensional finite element simulation models are established: one for a line without phase spacers and the other for a line with phase spacers. The models include straight cement poles, crossarms, post insulators, conductors, and phase spacers. The material parameters for different parts of the models are shown in Table 1.

[0062] Table 1 Material parameters of the simulation model

[0063]

[0064] like Figure 3 As shown, based on the actual parameters of different structures in the model, different parts are meshed with varying degrees of roughness. Since the main research object is the conductor, the meshes for the cement straight rods, hardware, insulators, and phase spacers can be relatively coarse, while the meshes for the conductors are relatively finer.

[0065] In this embodiment, a gravity load is applied to the model in the Pre-Stress Model, the bases of the two straight concrete poles are set to a fixed mode, and the two ends of the six wires are also set to a fixed mode. The same boundary conditions are set for both models, and solutions are performed for both models separately.

[0066] The vibration process of a conductor is a complex process of superposition of the frequencies of its various modes, with the first few low-order modal frequencies and modal shapes playing a major role. For example... Figure 4 The figure shown is a calculation result diagram of the four-mode shape of the circuit before the spacer bar is installed. Figure 5 The figure shows the calculation results of the first four modes of the circuit with spacer bars installed. The calculation results of the first four modes of frequency are shown in Table 2, and the calculation results of the vibration amplitude of the first four modes are shown in Table 3.

[0067] Table 2 Calculation results of the first four modal frequencies

[0068]

[0069] Table 3 Calculation results of vibration amplitude for the first four modes

[0070]

[0071] After installing spacers, the modal frequencies of the line increased, and the higher the modal order, the more significant the increase in modal frequency. Without spacers, the conductor galloping mode shape was close to a complete half-wave. With spacers, the galloping mode shape was greater than one half-wave, and in the fourth mode, it approached two complete half-waves. The increase in the number of half-waves in the conductor mode shape can reduce the amplitude of the vibration. Table 3 shows that installing spacers significantly reduced the conductor amplitude. Although the amplitude in the fourth mode was slightly greater than that without spacers, the difference was not significant. Considering the first four modes, it can be concluded that installing spacers can suppress the amplitude of conductor galloping. This can reduce the probability of galloping-induced faults and improve the safe and reliable operation of the power grid.

[0072] It should be emphasized that the embodiments described in this invention are illustrative rather than limiting. Therefore, this invention includes, but is not limited to, the embodiments described in the specific implementation. Any other implementations derived by those skilled in the art based on the technical solutions of this invention are also within the scope of protection of this invention.

Claims

A method for analyzing the anti-galloping effect of phase-to-phase spacers for 1.10kV overhead insulated conductors, wherein the spacer is positioned transversely along the extension direction of the overhead insulated conductor and longitudinally along a direction perpendicular to the extension direction of the overhead insulated conductor, characterized by: The spacer includes several overhead insulated conductor connecting rods, which are connected by a first insulated connecting rod. The overhead insulated conductor connecting rods are arranged horizontally, and different overhead insulated conductors are connected to both ends of the overhead insulated conductor connecting rods respectively. The overhead insulated conductor connecting rod includes a connecting hardware, a second insulated connecting rod, and a wire clamp. The two longitudinal ends of the connecting hardware are respectively connected to the second insulated connecting rod, and the other end of the second insulated connecting rod is respectively connected to the wire clamp. The second insulated connecting rod also has a rubber awning for support and insulation. The wire clamp includes a rubber pad, a fastening mechanism, and a fixing clamp. The fastening mechanism controls the opening and closing of the fixing clamp to connect the overhead insulated wire. The fastening mechanism is connected to the second insulating connecting rod through the rubber pad. The connecting hardware includes cross-shaped connecting hardware and T-shaped connecting hardware. The horizontally arranged overhead insulated wire connecting rod in the middle is connected to other overhead insulated wire connecting rods through the cross-shaped connecting hardware. The horizontally arranged overhead insulated wire connecting rods at both ends are connected to other overhead insulated wire connecting rods through the T-shaped connecting hardware. The method for analyzing the effectiveness of anti-fighting techniques includes the following steps: Step 1: Establish a simulation model of a 10kV double-circuit vertically arranged line with spacers installed; Step 2: Mesh the simulation model established in Step 1; Step 3: Perform prestressed modal analysis on the simulation model generated by mesh generation in Step 2 and obtain the analysis results; Step 4: Process the analysis results to obtain the anti-galloping effect of the phase spacers for overhead insulated conductors.

2. The method for analyzing the anti-galloping effect of phase-to-phase spacers for 10kV overhead insulated conductors according to claim 1, characterized in that: The specific implementation method of step 1 is as follows: Based on the actual structural parameters of the overhead insulated conductor, a three-dimensional finite element simulation model of a 10kV double-circuit vertically arranged overhead line with spacers installed is established. At the same time, the connection between each part in the model is set so that the contact surfaces neither separate nor slide relative to each other.

3. The method for analyzing the anti-galloping effect of the phase-to-phase spacer bar of the 10kV overhead insulated conductor according to claim 1, characterized in that: The specific implementation method of step 2 is as follows: according to the actual parameters of different structures in the simulation model, different parts are divided into meshes with different roughness.

4. The method for analyzing the anti-galloping effect of the phase-to-phase spacer bar of the 10kV overhead insulated conductor according to claim 1, characterized in that: The specific implementation method of step 3 is as follows: in, For the first i First natural vibration frequency, For the quality matrix, Here is the stiffness matrix. For the first i The eigenvectors of the modal shape.

5. The method for analyzing the anti-galloping effect of the phase-to-phase spacer bar of the 10kV overhead insulated conductor according to claim 1, characterized in that: The specific implementation method of step 4 is as follows: based on the modal shape and modal frequency of different orders in step 3, the anti-galling effect of the phase spacer of the 10kV double-circuit vertically arranged line is analyzed.

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