Power transmission tower wind vibration response identification method considering influence of power transmission line

Abstract

The invention discloses a power transmission tower wind-induced vibration response identification method considering the influence of a power transmission line, and the method comprises the steps: collecting the wind-induced vibration response time history data of a power transmission tower structure, carrying out the preprocessing and adaptive time-frequency decomposition, and carrying out the time-frequency feature analysis of each obtained response component; classifying and identifying the response components; identifying a response component which reflects the inherent dynamic characteristics of the power transmission tower structure and has concentrated and stable frequency distribution as a resonance response component, and identifying a response component which reflects the random action of an external wind field and the coupling transmission influence of power transmission line vibration through a tower line as a background response component; and respectively reconstructing the resonance response component and the background response component to obtain a resonance response and a background response in the wind vibration response of the power transmission tower structure. Resonance and background response obtained by the method can visually show structural dynamic characteristics and external excitation effects, and a high-quality data basis is provided for structural health monitoring and dynamic performance evaluation.

Description

Technical Field

[0001] This invention relates to the fields of structural dynamics and signal processing technology, specifically to a method for identifying the wind-induced vibration response of transmission towers that takes into account the influence of transmission lines, and more particularly to a method that can separate and reconstruct the resonant components and background components in structural vibration signals under complex external excitation. Background Technology

[0002] Transmission tower structures exhibit significant wind-induced vibration responses under wind loads, which is a crucial factor affecting the safe operation of transmission lines. In practical engineering, transmission towers are typically not independent structures but rather form a tower-line system together with insulators and transmission lines. Transmission lines possess dynamic characteristics such as large spans, high flexibility, and dense modalities, making them prone to significant vibrations under wind excitation. These vibrations are transmitted to the transmission tower structure through the tower-line connection, thus having a non-negligible impact on the tower's wind-induced vibration response.

[0003] Under tower-line system conditions, the wind-induced vibration response of transmission towers not only includes vibration components dominated by the inherent dynamic characteristics of the tower itself, but also superimposed with additional response components caused by the coupling of transmission line vibration through the tower and line. This results in more complex characteristics in terms of frequency composition, energy distribution, and time-varying properties. The high degree of overlap between these response components from different sources in the time and frequency domains increases the difficulty of analyzing and identifying the wind-induced vibration response of transmission towers.

[0004] Existing analytical methods for wind-induced vibration response of transmission towers are mostly based on frequency domain or time-frequency analysis techniques such as Fourier transform and wavelet transform. These methods typically assume that the tower response is primarily controlled by a single structural system, making it difficult to effectively distinguish the response components caused by the coupling between the tower's own vibration and the transmission line vibration. When the tower-line coupling effect is significant, these methods often fail to accurately identify the dominant dynamic components in the tower's wind-induced vibration response, thus affecting the analysis of the transmission tower's dynamic characteristics and wind-induced vibration mechanism.

[0005] Therefore, it is necessary to propose a method for identifying the wind-induced vibration response of transmission towers that is suitable for tower-line system conditions, taking into full account the coupling effect of transmission line vibration, so as to effectively distinguish the different physical sources in the wind-induced vibration response of the tower and improve the physical rationality and engineering applicability of the wind-induced vibration response analysis. Summary of the Invention

[0006] The purpose of this invention is to provide a method for identifying the wind-induced vibration response of transmission towers that takes into account the influence of transmission line coupling. Addressing the problem of the superposition and difficulty in distinguishing different dynamic components in the wind-induced vibration response of transmission towers under tower-line system conditions, this invention, without treating the transmission tower as an isolated structure, achieves effective identification and separation of the tower-dominated resonant response and the background response caused by the coupling of external wind field and transmission line vibration through adaptive decomposition and feature analysis of the tower's wind-induced vibration response signal.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines, comprising the following steps:

[0008] S1. First, collect the wind vibration response time history data of the transmission tower structure under wind action under the tower-line system conditions, and preprocess the wind vibration response time history.

[0009] S2. Considering the impact of transmission line vibration on the wind-induced vibration response of the transmission tower through tower-line coupling, the preprocessed wind-induced vibration response is subjected to adaptive time-frequency decomposition to obtain several response components with different time scales and frequency characteristics.

[0010] S3. Perform time-frequency characteristic analysis on each obtained response component and extract characteristic parameters to characterize the frequency stability, frequency fluctuation characteristics and energy distribution characteristics of the response component.

[0011] S4. Based on the correspondence between the time-frequency characteristics of the response components and the inherent frequency characteristics of the transmission tower structure, the response components are classified and identified.

[0012] S5. The response components that mainly reflect the inherent dynamic characteristics of the transmission tower structure and have a concentrated and stable frequency distribution are identified as resonant response components, and the response components that mainly reflect the random effects of the external wind field and the influence of the transmission line vibration transmitted through the tower-line coupling are identified as background response components.

[0013] S6. Reconstruct the resonant response component and the background response component respectively to obtain the resonant response and background response in the wind vibration response of the transmission tower structure.

[0014] Preferably, in step S1, the specific steps include acquiring the wind vibration response signal of the transmission tower structure under wind action. The wind vibration response signal is derived from measured data acquired by the field monitoring system, wind tunnel test data considering the influence of the transmission line, or structural dynamic response data obtained by numerical analysis based on the tower-line coupling model. The acquired wind vibration response signal includes at least one of displacement response, velocity response, or acceleration response, preferably the dynamic response signal at the top of the tower or a key location on the tower body, so as to highlight the influence of transmission line vibration on the tower body response.

[0015] Preferably, in step S1, the acquired wind vibration response signal is preprocessed. The preprocessing includes removing trend terms, abnormal drift components, and measurement noise interference from the signal, so that the processed signal meets the requirements of subsequent empirical mode decomposition and instantaneous frequency analysis. For wind vibration response signals with long duration and significant changes in wind field conditions, the signal can be segmented as needed to ensure the stability of the analysis process and the comparability of the results. The preprocessed wind vibration response signal is used as the input signal for the subsequent empirical mode decomposition step.

[0016] Preferably, in step S2, the preprocessed wind vibration response signal of the transmission tower structure is decomposed using the empirical mode decomposition method, which decomposes the original wind vibration response signal into several intrinsic mode components with different time scale characteristics and a residual component; the empirical mode decomposition is an adaptive decomposition method that can decompose the nonlinear and non-stationary wind vibration response under the action of the tower line system into a set of approximately narrow-band intrinsic mode components according to the characteristics of the signal itself; through empirical mode decomposition, the wind vibration response signal is expressed as the superposition of each intrinsic mode component and the residual component, and its expression is shown in equation (1):

[0017] (1)

[0018] Among them, IMF i r(t) represents the i-th intrinsic mode component, r(t) represents the residual component, and n is the number of intrinsic mode components.

[0019] Preferably, in step S3, each intrinsic mode component obtained in step S2 is subjected to Hilbert transform processing to convert the intrinsic mode component into a corresponding analytical signal, and its instantaneous amplitude, instantaneous phase and instantaneous frequency information are extracted from the analytical signal; by analyzing the change characteristics of the instantaneous phase with time, the instantaneous frequency sequence corresponding to each IMF component is obtained, and the analytical signal of the i-th intrinsic mode component is expressed as Equation (2) through Hilbert transform:

[0020] (2)

[0021] Where H{} denotes the Hilbert transform operator, and j is the imaginary unit; the corresponding instantaneous frequency characteristics are obtained by differentiating the instantaneous phase of the analytic signal with respect to time.

[0022] Preferably, in step S4, the intrinsic modal components obtained in step S2 are combined with the instantaneous frequency and amplitude characteristics extracted in step S3 to screen the effectiveness of each intrinsic modal component, so as to determine the effective modal components that can truly reflect the wind vibration response characteristics of the transmission tower structure under the tower-line system conditions. In the screening process, each intrinsic modal component is comprehensively judged based on its frequency distribution characteristics, energy proportion, and instantaneous frequency stability. Intrinsic modal components whose frequency distribution deviates significantly from the vibration characteristics of the transmission tower structure, whose energy contribution is small, or whose frequency fluctuations are severe are not included as effective modal components in subsequent analysis. Intrinsic modal components with stable frequency characteristics, significant energy contribution, and that can reflect the coupled vibration characteristics of the tower body or tower-line are retained as effective modal components. After the above screening, a set of effective intrinsic modal components for subsequent classification and identification is obtained.

[0023] Preferably, in step S5, the effective intrinsic mode components obtained in step S4 are classified and identified according to their instantaneous frequency characteristics and energy distribution characteristics, and divided into two categories: resonant components and background components. Among them, the intrinsic mode components whose instantaneous frequency changes relatively stably over time, whose frequency distribution is concentrated, and which correspond to the inherent vibration characteristics of the transmission tower structure are identified as resonant components, which are used to characterize the dominant vibration response of the tower body under the tower-line system conditions. The intrinsic mode components whose instantaneous frequency changes significantly over time, whose frequency distribution range is wide, and which mainly reflect the external wind field effect and the vibration coupling effect of the transmission line are identified as background components.

[0024] Preferably, in step S6, based on the resonant component set and background component set obtained in step S5, the intrinsic mode components are superimposed and reconstructed to obtain the resonant response and background response in the wind vibration response of the transmission tower structure; wherein, the intrinsic mode components belonging to the resonant component set are superimposed to obtain the resonant response reflecting the inherent dynamic characteristics of the transmission tower structure; the intrinsic mode components belonging to the background component set are superimposed to obtain the background response reflecting the effects of the external wind field and the coupling influence of the transmission line vibration; the superposition of the resonant response and the background response constitutes the reconstructed signal corresponding to the original wind vibration response.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. This invention addresses the problem of overlapping components and unclear physical origins in the wind-induced vibration response of transmission towers under tower-line system conditions due to the vibration coupling of transmission lines. By adaptively decomposing and identifying features of the wind-induced vibration response signal of the transmission tower, the invention achieves effective identification and separation of the resonant response dominated by the tower body and the background response caused by the external wind field and the vibration coupling of transmission lines.

[0027] 2. The decomposition and identification method based on the response characteristics adopted in this invention can adapt to the non-stationary and multi-scale characteristics of the wind vibration response signal of the transmission tower under the tower-line system conditions. Without simplifying the transmission tower into an isolated structure or directly introducing the transmission line response signal, it can more realistically reflect the dynamic characteristics of the wind vibration response of the transmission tower in the tower-line system, and improve the physical rationality and stability of the response identification results.

[0028] 3. The resonance response and background response obtained by this invention have clear physical meanings and can provide reliable technical support for the analysis of wind vibration response of transmission towers considering the influence of transmission lines, dynamic performance evaluation and structural safety and health monitoring. It has good engineering applicability and promotion value. Attached Figure Description

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0030] In the attached diagram:

[0031] Figure 1 This is a flowchart of a method for identifying the wind-induced vibration response of transmission towers that takes into account the influence of transmission lines, according to the present invention.

[0032] Figure 2 This is a schematic diagram of the three-tower, four-span, eight-line system of the present invention;

[0033] Figure 3 This is the spectrum of the IMF (Intrinsic Mode Function) components of the tower top displacement response of the present invention;

[0034] Figure 4 This is a histogram of the instantaneous frequency distribution of each IMF in the present invention under constant frequency coordinates;

[0035] Figure 5 This is a box plot of the instantaneous frequency distribution of each IMF in the present invention under constant frequency coordinates;

[0036] Figure 6 This is the time history diagram of the tower top displacement response resonance and background components of the present invention;

[0037] Figure 7 This is the spectrum diagram of the tower top displacement response resonance and background components of the present invention. Detailed Implementation

[0038] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] Example: This invention addresses the wind-induced vibration response characteristics of transmission tower structures under tower-line system conditions. Considering the coupling effect of transmission line vibration on the tower's wind-induced vibration response, it provides a method for identifying the background and resonant components of the wind-induced vibration response of transmission tower structures. This method, based on empirical mode decomposition and Hilbert instantaneous frequency analysis, processes the wind-induced vibration response signal of the transmission tower structure under tower-line system conditions to identify and separate the resonant component dominated by the structure's inherent dynamic characteristics from the background component caused by the coupling of external wind field and transmission line vibration. For example... Figure 1 As shown, the method includes the following steps:

[0040] (I) Acquisition and Preprocessing of Structural Wind Vibration Response Signals

[0041] This step aims to obtain the wind-induced vibration response signal that reflects the true dynamic response characteristics of the transmission tower structure under tower-line system conditions, and to preprocess it to lay a reliable foundation for subsequent analysis.

[0042] The wind-induced vibration response signal of the transmission tower structure under wind load is obtained. This signal can originate from measured data acquired by a field monitoring system, wind tunnel test data considering the influence of the transmission line, or structural dynamic response data obtained through numerical analysis based on a tower-line coupling model. The obtained wind-induced vibration response signal includes at least one of displacement response, velocity response, or acceleration response, preferably a dynamic response signal from the tower top or a key location on the tower body, to highlight the impact of transmission line vibration on the tower's response.

[0043] The acquired wind vibration response signal is preprocessed, including removing trend terms, abnormal drift components, and measurement noise interference, so that the processed signal meets the requirements of subsequent empirical mode decomposition and instantaneous frequency analysis. For wind vibration response signals with long durations and significant changes in wind field conditions, the signal can be segmented as needed to ensure the stability of the analysis process and the comparability of the results.

[0044] The preprocessed wind vibration response signal is used as the input signal for the subsequent empirical mode decomposition step.

[0045] (ii) Extraction of intrinsic mode components from empirical mode decomposition

[0046] The preprocessed wind-induced vibration response signal of the transmission tower structure is decomposed using the empirical mode decomposition method, which decomposes the original wind-induced vibration response signal into several intrinsic mode components with different time-scale characteristics and a residual component. The empirical mode decomposition is an adaptive decomposition method that can decompose the nonlinear and non-stationary wind-induced vibration response of the tower system into a set of approximately narrow-band intrinsic mode components based on the characteristics of the signal itself.

[0047] Through empirical mode decomposition, the wind-induced vibration response signal can be expressed as the superposition of each intrinsic mode component and the residual component, as shown in equation (1):

[0048] (1)

[0049] Among them, IMF i r(t) represents the i-th intrinsic mode component, r(t) represents the residual component, and n is the number of intrinsic mode components.

[0050] In the specific implementation process, depending on the complexity of the wind vibration response signal under the tower line system, the original signal can be decomposed multiple times using ensemble empirical mode decomposition or its improved form to reduce the influence of mode aliasing caused by transmission line vibration coupling on the decomposition results.

[0051] (III) Extraction of Hilbert instantaneous frequency features

[0052] Each intrinsic mode component obtained in step (ii) is subjected to Hilbert transform to convert it into a corresponding analytic signal, thereby extracting its instantaneous amplitude and instantaneous frequency characteristics. The instantaneous frequency characteristics are used to describe the frequency variation characteristics of the intrinsic mode components in the time domain.

[0053] Through the Hilbert transform, the analytic signal of the i-th intrinsic mode component is expressed as Equation (2):

[0054] (2)

[0055] Here, H{} denotes the Hilbert transform operator, and j is the imaginary unit. The instantaneous frequency characteristics can be obtained by differentiating the instantaneous phase of the analytic signal with respect to time.

[0056] In the specific implementation process, the instantaneous frequency distribution characteristics, frequency stability and instantaneous amplitude variation characteristics of each intrinsic mode component can be statistically analyzed to provide characteristic basis for distinguishing the inherent vibration response of the tower body from the background response caused by the coupling of the transmission line.

[0057] (iv) Screening of intrinsic modal components

[0058] For the intrinsic modal components obtained in step (ii), combined with the instantaneous frequency and amplitude characteristics extracted in step (iii), the effectiveness of each intrinsic modal component is screened to determine the effective modal components that can truly reflect the wind vibration response characteristics of the transmission tower structure under the tower-line system conditions.

[0059] During the screening process, each intrinsic mode component (IMF) is comprehensively evaluated based on its frequency distribution characteristics, energy proportion, and instantaneous frequency stability. IMFs with frequency distributions significantly deviating from the transmission tower structure's vibration characteristics, small energy contributions, or drastic frequency fluctuations are excluded from subsequent analysis as valid IMFs. IMFs with stable frequency characteristics, significant energy contributions, and the ability to reflect the coupled vibration characteristics of the tower or tower-line are retained as valid IMFs. To ensure the physical consistency of the decomposition results, the obtained IMF sequences undergo validity screening. This process incorporates multi-dimensional discrimination criteria, including:

[0060] Frequency range constraints: Based on the structure's natural frequency and the wind load spectrum distribution, set reasonable upper and lower frequency limits to eliminate IMFs whose instantaneous frequency or center frequency exceeds the range;

[0061] Energy threshold screening: Calculate the energy level and proportion of each IMF. Components with excessively low energy usually correspond to noise or weak disturbances and should be eliminated.

[0062] Spectral kurtosis discrimination: Spectral kurtosis is used to measure the sharpness and non-Gaussianity of the spectral distribution, and IMFs with abnormally high or low kurtosis values ​​are eliminated to exclude non-physical components.

[0063] The above screening process can significantly improve the stability and physical rationality of component separation, ensuring that the retained IMF is closely related to the actual dynamic characteristics of the structure.

[0064] After the above screening, a set of effective intrinsic mode components for subsequent classification and recognition is obtained.

[0065] (v) Classification and identification of intrinsic modal components (resonance components and background components)

[0066] Based on the instantaneous frequency characteristics and energy distribution characteristics of the effective intrinsic mode components obtained in step (iv), each intrinsic mode component is classified and identified into two categories: resonant components and background components.

[0067] Among them, the intrinsic mode components whose instantaneous frequency changes relatively stably over time, have a concentrated frequency distribution, and correspond to the inherent vibration characteristics of the transmission tower structure are identified as resonance components, used to characterize the dominant vibration response of the tower body under tower-line system conditions; the intrinsic mode components whose instantaneous frequency changes significantly over time, have a wide frequency distribution range, and mainly reflect the effects of external wind fields and the coupling effect of transmission line vibration are identified as background components.

[0068] In the specific implementation process, the intrinsic mode components can be automatically classified and identified based on the instantaneous frequency statistical characteristics, energy proportion or frequency band distribution characteristics, thereby forming a set of resonant components and a set of background components.

[0069] (vi) Response Restructuring

[0070] Based on the set of resonant components and the set of background components obtained in step (v), the intrinsic mode components are superimposed and reconstructed to obtain the resonant response and background response in the wind vibration response of the transmission tower structure.

[0071] The resonant response, reflecting the inherent dynamic characteristics of the transmission tower structure, is obtained by superimposing the eigenmode components belonging to the resonant component set. The background response, reflecting the effects of the external wind field and the coupling influence of transmission line vibration, is obtained by superimposing the eigenmode components belonging to the background component set. The superposition of the resonant response and the background response constitutes the reconstructed signal corresponding to the original wind-induced vibration response.

[0072] Through the above reconstruction process, the resonant response and background response in the wind-induced vibration response of the transmission tower structure under the tower-line system condition were separated and characterized, providing a clear signal basis for further analysis of the influence of the transmission line on the wind-induced vibration response of the tower.

[0073] The specific benefits of this method include the following:

[0074] Taking the three-tower, four-span, eight-line transmission tower-transmission line coupling system as the research object, such as Figure 2 As shown, a wind-induced vibration analysis model for a tower-line system considering the dynamic coupling effect between the transmission line and the transmission tower is established. In this system, the vibration generated by the transmission line under wind action is transmitted to the tower body through the tower-line connection, thus significantly affecting the overall wind-induced vibration response characteristics of the transmission tower structure.

[0075] Under given wind conditions, an incoming wind is applied to the tower-line system, with an average wind speed of 10 m / s at a reference height of 10 m and a wind direction angle of 60°. The displacement response time history of the top of the intermediate transmission tower under wind action is obtained as the analysis object. The wind vibration response background and resonance component identification method considering the influence of the transmission line, proposed in this invention, is used to process the total displacement response of the tower top, achieving separation of the background response and resonance response in the wind vibration response of the tower body.

[0076] First, empirical mode decomposition (EMD) was performed on the time history of the tower top displacement response to obtain several intrinsic mode function (EMF) components. Then, combining Hilbert instantaneous frequency analysis with the EMF component screening and classification method proposed in this invention, the decomposed modal components were analyzed. The analysis results show that six effective EMF components were identified in the wind-induced vibration response of the tower system, such as... Figure 3 As shown, the spectral characteristics of each intrinsic mode component after decomposition of the tower top displacement response are given, which correspond to the resonance components of the inherent characteristics of the tower body, the resonance components excited by the higher-order vibration under the coordinated vibration of the tower and the line, the resonance components excited by the second-higher-order vibration under the coordinated vibration of the tower and the line, and the three background components under random wind field excitation.

[0077] Where freMedian represents the median instantaneous frequency of the intrinsic mode components, E represents the energy of the intrinsic mode components, r represents the energy proportion of the intrinsic mode components in the corresponding frequency band, and σ² represents the variance of the instantaneous frequency of the intrinsic mode components. These characteristic parameters are used to quantitatively characterize the differences in frequency stability, energy concentration, and physical origin of different intrinsic mode components.

[0078] like Figure 4 and Figure 5 As shown, histograms and box plots of the instantaneous frequency distribution of each IMF under constant frequency coordinates are further presented. These results verify that the method of this invention can effectively distinguish between the resonant response dominated by the inherent vibration of the transmission tower structure and the background response caused by the random effects of the wind field and the coupling of transmission line vibrations under tower-line system conditions.

[0079] The effectiveness of the methods described above can be seen as follows: Figure 6 and Figure 7As shown, the wind vibration response identification method proposed in this invention can effectively separate and characterize different dynamic components in the wind vibration response of transmission tower structures, taking into account the influence of transmission lines. It overcomes the shortcomings of accurately identifying the tower-line coupling effect when only analyzing a single tower structure, and has good engineering applicability and promotion value.

[0080] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines, characterized in that, Includes the following steps: S1. First, collect the wind vibration response time history data of the transmission tower structure under wind action under the tower-line system conditions, and preprocess the wind vibration response time history. S2. Adaptive time-frequency decomposition is performed on the preprocessed wind vibration response to obtain several response components with different time scales and frequency characteristics. S3. Perform time-frequency characteristic analysis on each obtained response component and extract characteristic parameters to characterize the frequency stability, frequency fluctuation characteristics and energy distribution characteristics of the response component. S4. Based on the correspondence between the time-frequency characteristics of the response components and the inherent frequency characteristics of the transmission tower structure, the response components are classified and identified. S5. The response components that reflect the inherent dynamic characteristics of the transmission tower structure and have a concentrated and stable frequency distribution are identified as resonant response components, and the response components that reflect the random action of the external wind field and the influence of the transmission line vibration transmitted through the tower-line coupling are identified as background response components. S6. Reconstruct the resonant response component and the background response component respectively to obtain the resonant response and background response in the wind vibration response of the transmission tower structure.

2. The method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines according to claim 1, characterized in that: In step S1, the specific steps include acquiring the wind vibration response signal of the transmission tower structure under wind action. The wind vibration response signal comes from the measured data acquired by the field monitoring system, the wind tunnel test data considering the influence of the transmission line, or the structural dynamic response data obtained by the numerical analysis method based on the tower-line coupling model. The acquired wind vibration response signal includes at least one of displacement response, velocity response, or acceleration response.

3. The method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines according to claim 2, characterized in that: In step S1, the acquired wind vibration response signal is preprocessed. The preprocessing includes removing trend terms, abnormal drift components and measurement noise interference from the signal, so that the processed signal meets the requirements of subsequent empirical mode decomposition and instantaneous frequency analysis. The preprocessed wind vibration response signal is used as the input signal for the subsequent empirical mode decomposition step.

4. The method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines according to claim 3, characterized in that: In step S2, the preprocessed wind-induced vibration response signal of the transmission tower structure is decomposed using the empirical mode decomposition method, which decomposes the original wind-induced vibration response signal into several intrinsic mode components with different time scale characteristics and a residual component. Through empirical mode decomposition, the wind-induced vibration response signal is represented as the superposition of each intrinsic mode component and the residual component, and its expression is shown in equation (1): （1） Among them, IMF i r(t) represents the i-th intrinsic mode component, r(t) represents the residual component, and n is the number of intrinsic mode components.

5. The method for identifying the wind-induced vibration response of transmission towers considering the influence of transmission lines according to claim 4, characterized in that: In step S3, each intrinsic mode component obtained in step S2 is subjected to Hilbert transform to convert the intrinsic mode component into a corresponding analytical signal, and its instantaneous amplitude, instantaneous phase and instantaneous frequency information are extracted from the analytical signal; by analyzing the change characteristics of the instantaneous phase with time, the instantaneous frequency sequence corresponding to each IMF component is obtained. Through Hilbert transform, the analytical signal of the i-th intrinsic mode component is expressed as Equation (2): （2） Where H{} denotes the Hilbert transform operator, and j is the imaginary unit; the corresponding instantaneous frequency characteristics are obtained by differentiating the instantaneous phase of the analytic signal with respect to time.

6. The method for identifying the wind-induced vibration response of a transmission tower considering the influence of transmission lines, as described in claim 5, is characterized in that: In step S4, the intrinsic mode components obtained in step S2 are combined with the instantaneous frequency and amplitude characteristics extracted in step S3 to screen the effectiveness of each intrinsic mode component in order to determine the effective mode components that can truly reflect the wind vibration response characteristics of the transmission tower structure under the tower-line system conditions. During the screening process, each intrinsic mode component is comprehensively judged based on its frequency distribution characteristics, energy proportion, and instantaneous frequency stability. Intrinsic modal components with stable frequency characteristics, significant energy contribution, and the ability to reflect the coupled vibration characteristics of the tower body or tower line are retained as effective modal components. After the above screening, a set of effective intrinsic modal components for subsequent classification and identification is obtained.

7. The method for identifying the wind-induced vibration response of a transmission tower considering the influence of transmission lines according to claim 6, characterized in that: In step S5, the effective intrinsic mode components obtained in step S4 are classified and identified according to their instantaneous frequency characteristics and energy distribution characteristics, and divided into two categories: resonance components and background components.

8. The method for identifying the wind-induced vibration response of a transmission tower considering the influence of transmission lines according to claim 7, characterized in that: In step S6, based on the resonant component set and background component set obtained in step S5, the intrinsic mode components are superimposed and reconstructed to obtain the resonant response and background response in the wind vibration response of the transmission tower structure. Specifically, the intrinsic mode components belonging to the resonant component set are superimposed to obtain the resonant response reflecting the inherent dynamic characteristics of the transmission tower structure; the intrinsic mode components belonging to the background component set are superimposed to obtain the background response reflecting the effects of the external wind field and the coupling influence of the transmission line vibration. The superposition of the resonant response and the background response constitutes the reconstructed signal corresponding to the original wind vibration response.

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