A lightning arrester with self-sensing function and a wind vibration state monitoring and evaluation method

Abstract

The application discloses a lightning arrester with self-sensing function and a wind vibration state monitoring and evaluation method, and mainly solves the technical problems that the existing lightning arrester lacks online monitoring means, cannot realize real-time sensing of the wind vibration state, cannot identify the risk of vortex-induced resonance, and lacks early warning capability, and that the traditional electrical sensor is sensitive to electromagnetic interference and difficult to insulate in a high-voltage environment. The lightning arrester comprises a lightning arrester body, a fiber grating sensing array, a fiber grating demodulator and a data analysis and early warning server. The application can realize all-weather and online monitoring of the wind vibration state of the lightning arrester, provides data support for state maintenance, can identify the resonance risk in real time during operation, and timely issues a warning when the resonance occurs, so that fatigue fracture caused by continuous accumulation of the resonance is avoided, and the real fatigue state of the lightning arrester can be more accurately reflected, thereby providing a scientific basis for maintenance personnel to make a maintenance plan.

Description

Technical Field

[0001] This invention relates to a surge arrester and a condition monitoring and evaluation method, specifically to a surge arrester with self-sensing function and a wind-induced vibration condition monitoring and evaluation method. Background Technology

[0002] Surge arresters are key devices in power systems that limit overvoltage and protect the insulation of electrical equipment. They are widely used in substations, transmission lines, and other locations. With the continuous increase in power grid voltage levels and the frequent occurrence of extreme weather events, the mechanical safety of surge arresters, especially their wind resistance in certain specific locations such as strong wind environments, is receiving increasing attention.

[0003] Surge arresters are typically slender structures, ranging in height from several meters to tens of meters. Their large length-to-slenderness ratio makes them prone to bending deformation and vibration under wind loads. Existing research indicates that wind-induced failure of surge arresters mainly occurs in two modes: first, static strength failure caused by extreme strong winds, manifested as root flange fracture or complete overturning; second, fatigue failure caused by long-term wind-induced vibration, especially when wind speed and the natural frequency of the surge arrester structure generate vortex-induced resonance, continuous periodic vibration leads to cumulative material damage, eventually resulting in fatigue fracture.

[0004] To address the aforementioned problems, some solutions already exist in the existing technology. For example, structural strength can be improved by increasing the cross-sectional size of the surge arrester or using high-strength materials; or the wind resistance of the surge arrester can be verified during the design phase through theoretical calculations and finite element simulations. However, the existing technology still has the following shortcomings:

[0005] (1) Lack of online monitoring methods makes it impossible to perceive wind-induced vibration status in real time.

[0006] The wind resistance design of existing surge arresters mainly relies on theoretical calculations and simulation analysis. However, wind loads in actual operation are random, unsteady, and spatially uneven, making it difficult for theoretical calculations to fully cover all operating conditions.

[0007] (2) Unable to identify the risk of vortex-induced resonance and lacks early warning capability.

[0008] Vortex-induced resonance is one of the main causes of fatigue failure in slender structures. When wind flows past a surge arrester, it creates alternating vortices on its leeward side, generating periodic alternating forces. If the vortex shedding frequency is close to the natural frequency of the surge arrester structure, resonance will occur, leading to a sharp amplification of the amplitude. Currently, there are no monitoring methods capable of identifying the characteristics of vortex-induced resonance, making it impossible to issue timely warnings when resonance occurs.

[0009] (3) The application of traditional electrical sensors is limited in high-voltage environments.

[0010] In recent years, some studies have attempted to install accelerometers or strain sensors on power equipment for condition monitoring. However, traditional electrical sensors suffer from electromagnetic interference sensitivity and insulation coordination difficulties in high-voltage electric fields, and require power supply and signal transmission cables, increasing the complexity and safety risks of on-site implementation. Fiber Bragg grating (FBG) sensing technology, due to its passive nature, immunity to electromagnetic interference, small size, ability to be serially connected at multiple points, and ease of embedding within structures, has been widely used in structural health monitoring in recent years. However, a technical solution has yet to be found that integrates FBG sensors with the surge arrester body and utilizes them for online monitoring of wind-induced vibration and fatigue life assessment. Summary of the Invention

[0011] The purpose of this invention is to address the technical problems of existing surge arresters, such as the lack of online monitoring methods, inability to perceive wind-induced vibration status in real time, inability to identify vortex-induced resonance risks, lack of early warning capabilities, and the sensitivity to electromagnetic interference and difficulties in insulation coordination when using traditional electrical sensors in high-voltage environments. This invention provides a surge arrester with self-sensing function and a method for monitoring and evaluating wind-induced vibration status.

[0012] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0013] A surge arrester with self-sensing function, comprising a surge arrester body, is characterized by:

[0014] It also includes fiber Bragg grating sensor arrays, fiber Bragg grating demodulators, and data analysis and early warning servers;

[0015] The fiber optic grating sensor array is pre-embedded inside the surge arrester body and is used to measure the axial strain distribution of the root section of the surge arrester body, the triaxial vibration acceleration of the top of the surge arrester body, and the temperature of the strain-free area of ​​the surge arrester body.

[0016] The fiber Bragg grating demodulator is connected to the fiber Bragg grating sensor array via an optical cable. It is used to emit a broadband light source to the fiber Bragg grating sensor array and receive reflected light signals to demodulate the corresponding wavelength data.

[0017] The data analysis and early warning server is communicatively connected to both the fiber optic grating demodulator and the wind speed sensor installed around the surge arrester body. It receives demodulated wavelength data and measured real-time wind speed data, and performs the following processing:

[0018] a. Calculate the real-time strain value based on the axial strain distribution, and perform temperature compensation based on the temperature of the strain-free region;

[0019] b. Calculate the bending moment vector borne by the surge arrester body based on the compensated real-time strain value;

[0020] c. Perform spectrum analysis based on triaxial vibration acceleration to identify the dominant vibration frequency in real time;

[0021] d. Calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance.

[0022] e. Perform rainflow counting on the real-time strain value-time history, and calculate the cumulative fatigue damage degree by combining the material SN curve and Miner's linear cumulative damage theory.

[0023] f. When the cumulative fatigue damage exceeds the preset threshold, a warning or alarm signal will be issued.

[0024] Furthermore, the fiber Bragg grating sensing array includes at least three fiber Bragg grating strain sensors, at least one fiber Bragg grating acceleration sensor, and at least one fiber Bragg grating temperature sensor;

[0025] The fiber optic strain sensors are evenly distributed circumferentially on the core surface or metal flange surface of the arrester root section, and are used to measure the axial strain distribution of the section.

[0026] The fiber optic accelerometer sensor is installed on top of the surge arrester and is used to measure the triaxial vibration acceleration of the top of the surge arrester.

[0027] The fiber optic temperature sensor is installed in the strain-free region of the surge arrester body to measure the temperature in that region.

[0028] Furthermore, the number of fiber optic strain sensors is three;

[0029] The number of fiber optic accelerometers and fiber optic temperature sensors is one each.

[0030] Furthermore, the fiber Bragg grating sensor array is led through the inside of the surge arrester body to the junction box at the bottom of the surge arrester body via a transmission optical fiber. The junction box is equipped with an optical fiber splicing device for connecting the transmission optical fiber to the fiber Bragg grating demodulator via an optical cable.

[0031] Meanwhile, the present invention also provides a method for monitoring and evaluating wind-induced vibration conditions, which is characterized by including the following steps:

[0032] Step 1: Sensor Installation and Integration

[0033] During the manufacturing process of the surge arrester body, a fiber optic grating sensor array is pre-embedded inside the surge arrester body; then the fiber optic grating sensor array is sequentially connected to a fiber optic grating demodulator and a data analysis and early warning server to form the aforementioned surge arrester with self-sensing function.

[0034] Step 2: Data Acquisition and Demodulation

[0035] A broadband light source is emitted to the fiber Bragg grating sensor array through a fiber Bragg grating demodulator, and the reflected light signal is received to demodulate the corresponding wavelength data.

[0036] Step 3: Receive the demodulated wavelength data through the data analysis and early warning server, and perform the following processing:

[0037] a. Calculate the real-time strain value based on the axial strain distribution, and perform temperature compensation based on the temperature of the strain-free region;

[0038] b. Calculate the bending moment vector borne by the surge arrester body based on the real-time strain value after temperature compensation;

[0039] c. Perform spectrum analysis based on triaxial vibration acceleration to identify the dominant vibration frequency in real time;

[0040] d. Calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance.

[0041] e. Perform rainflow counting on the real-time strain value-time history, and calculate the cumulative fatigue damage degree by combining the material SN curve and Miner's linear cumulative damage theory.

[0042] f. When the cumulative fatigue damage exceeds the preset threshold, a warning or alarm signal will be issued.

[0043] Furthermore, step 3 specifically involves:

[0044] a. Calculate the real-time strain value based on the axial strain distribution, and calculate the real-time temperature change based on the center wavelength corresponding to the temperature in the strain-free region. The real-time strain value is then temperature-compensated according to the following formula to obtain the compensated real-time strain value. :

[0045] ;

[0046] In the formula: This is the initial center wavelength of the fiber optic strain sensor; This represents the drift of the center wavelength of the fiber optic strain sensor. The thermo-optic coefficient of the optical fiber material; The coefficient of thermal expansion of the optical fiber material; The effective elastic-optical coefficient of the optical fiber material;

[0047] b. The following method is used to calculate the bending moment vector borne by the surge arrester body based on the compensated real-time strain value:

[0048] b.1. Based on the compensated real-time strain value, calculate the maximum bending strain amplitude according to the following formula. :

[0049] ;

[0050] In the formula: , and These are the real-time strain values ​​after compensation at three different locations;

[0051] b.2. Calculate the bending moment vector borne at the root of the surge arrester body according to the following formula. :

[0052] ;

[0053] In the formula: The elastic modulus of the core material of the surge arrester; The moment of inertia of the cross section; This is the distance from the location of the fiber optic strain sensor to the neutral axis of the cross section;

[0054] c. Perform a Fast Fourier Transform on the triaxial vibration acceleration to achieve spectral analysis and obtain the spectrum of the resultant horizontal acceleration. Based on the spectrum of the horizontal resultant acceleration. The real-time dominant vibration frequency is extracted according to the following formula. :

[0055] ;

[0056] d. Using the following method, calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data, and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance:

[0057] d.1. Based on the following formula and real-time wind speed data... and the effective diameter of the surge arrester body Calculate the theoretical frequency of vortex-induced shedding. :

[0058] ;

[0059] In the formula: The Strohar number was calibrated through wind tunnel testing.

[0060] d.2. Compare the theoretical frequency of vortex-induced shedding with the real-time dominant vibration frequency. When the following conditions are met, it is determined to be in a state of vortex-induced resonance:

[0061] and ;

[0062] In the formula: This is the frequency tolerance coefficient, with a value ranging from 0.1 to 0.15; This represents the root mean square value of the triaxial vibration acceleration; The preset acceleration threshold;

[0063] e. Using the following method, rainflow counting is performed on the real-time strain-time history, and the cumulative fatigue damage is calculated by combining the material SN curve and Miner's linear cumulative damage theory:

[0064] e.1. Perform rainflow counting on the real-time strain value-time history to obtain the amplitude of each stress cycle. mean and number of loops The mean stress was corrected using the Goodman formula, and the equivalent stress amplitude was calculated. :

[0065] ;

[0066] In the formula: The ultimate tensile strength of the material; The stress amplitude order;

[0067] e.2. Calculate the first step based on the material's SN curve. Fatigue life corresponding to stress amplitude :

[0068]

[0069] In the formula: These are strength coefficients related to the fatigue strength of materials. The slope parameter of the SN curve;

[0070] e.3. Calculate the cumulative fatigue damage degree using Miner's linear cumulative damage theory. :

[0071] ;

[0072] In the formula: This represents the maximum stress amplitude level.

[0073] f. When the cumulative fatigue damage degree When the first preset threshold is reached, an early warning signal is issued; when the accumulated fatigue damage degree... When the second preset threshold is reached, an alarm signal is issued; when it is determined that the state is in vortex-induced resonance, a resonance warning signal is issued.

[0074] Furthermore, in step 3, the first preset threshold is set to 0.8, and the second preset threshold is set to 1.0.

[0075] Compared with the prior art, the present invention has the following beneficial technical effects:

[0076] 1. This invention embeds a fiber optic grating sensor array inside the surge arrester body, completing the sensor implantation simultaneously during the surge arrester manufacturing process, thus achieving structural and functional integration of the sensor and the surge arrester. Compared to post-installation methods, this invention does not change the external dimensions and electrical performance of the surge arrester, while avoiding insulation hazards caused by external wiring, thereby improving the reliability and safety of the monitoring system.

[0077] 2. This invention utilizes an embedded fiber optic strain sensor to measure the strain distribution at the base of the surge arrester in real time, thereby inverting the bending moment vector and bending stress; and a top-mounted fiber optic accelerometer sensor to monitor the vibration frequency and amplitude in real time. Compared to traditional manual inspection methods, this invention achieves all-weather, online monitoring of the surge arrester's wind-induced vibration status, providing data support for condition-based maintenance.

[0078] 3. This invention extracts the dominant vibration frequency in real time through spectral analysis of triaxial vibration acceleration, and calculates the theoretical frequency of vortex-induced shedding by combining real-time wind speed data. Frequency comparison is then used to determine whether a vortex-induced resonance state is present. Compared to existing technologies that rely solely on theoretical calculations during the design phase, this invention can identify resonance risks in real time during operation and issue timely warnings when resonance occurs, preventing the continuous accumulation of resonance that could lead to fatigue fracture.

[0079] 4. This invention performs rainflow counting on the strain-time history, and combines the material SN curve and Miner's linear cumulative damage theory to quantitatively calculate the cumulative fatigue damage experienced by the surge arrester in the actual operating environment. Compared with existing technologies that rely solely on theoretical estimations during the design phase, this invention performs damage assessment based on measured stress spectra, which can more accurately reflect the true fatigue state of the surge arrester and provide a scientific basis for maintenance personnel to formulate maintenance plans. Attached Figure Description

[0080] Figure 1 This is a schematic diagram of the installation of a fiber optic strain sensor in an embodiment of a surge arrester with self-sensing function according to the present invention.

[0081] Figure 2 This is a schematic diagram of the installation of a fiber optic grating accelerometer sensor in an embodiment of a surge arrester with self-sensing function according to the present invention.

[0082] The attached figures are labeled as follows:

[0083] 1-Surge arrester body, 2-Fiber optic strain sensor, 3-Fiber optic accelerometer sensor. Detailed Implementation

[0084] To make the objectives, advantages, and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0085] See Figure 1 and Figure 2 This embodiment describes a surge arrester with self-sensing function, including a surge arrester body 1, a fiber optic grating sensor array, a fiber optic grating demodulator, and a data analysis and early warning server.

[0086] Specifically, the fiber Bragg grating sensing array includes at least three fiber Bragg grating strain sensors 2, at least one fiber Bragg grating accelerometer 3, and at least one fiber Bragg grating temperature sensor. In this embodiment, the number of fiber Bragg grating strain sensors 2 is three; the number of fiber Bragg grating accelerometer 3 and fiber Bragg grating temperature sensor is one each.

[0087] Three fiber Bragg grating strain sensors 2 are evenly distributed circumferentially on the core surface or metal flange surface of the arrester root section to measure the axial strain distribution of this section. One fiber Bragg grating accelerometer 3 is installed on the top of the arrester to measure the triaxial vibration acceleration at the top of the arrester. One fiber Bragg grating temperature sensor is installed in the strain-free region of the arrester body 1 to measure the temperature in that region.

[0088] Three fiber Bragg grating strain sensors 2, one fiber Bragg grating accelerometer 3, and one fiber Bragg grating temperature sensor are respectively led through transmission optical fibers along the inside of the surge arrester body 1 to the junction box at the bottom of the surge arrester body 1. The junction box is equipped with an optical fiber splicing device, which connects the transmission optical fiber to the fiber Bragg grating demodulator through an optical cable. Thus, the fiber Bragg grating demodulator transmits a broadband light source to the fiber Bragg grating sensor array and receives the reflected light signal to demodulate the corresponding wavelength data. This wavelength data includes the axial strain distribution of the root section of the surge arrester body 1, the triaxial vibration acceleration of the top of the surge arrester body 1, and the temperature of the strain-free region of the surge arrester body 1.

[0089] The data analysis and early warning server is communicatively connected to both the fiber Bragg grating demodulator and the wind speed sensors installed around the arrester body 1 (such as on a pole or adjacent mounting bracket). It receives demodulated wavelength data and measured real-time wind speed data, and performs the following processing:

[0090] a. Calculate the real-time strain value based on the axial strain distribution, and perform temperature compensation based on the temperature of the strain-free region;

[0091] b. Calculate the bending moment vector borne by the arrester body 1 based on the compensated real-time strain value;

[0092] c. Perform spectrum analysis based on triaxial vibration acceleration to identify the dominant vibration frequency in real time;

[0093] d. Calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance.

[0094] e. Perform rainflow counting on the real-time strain value-time history, and calculate the cumulative fatigue damage degree by combining the material SN curve and Miner's linear cumulative damage theory.

[0095] f. When the cumulative fatigue damage exceeds the preset threshold, a warning or alarm signal will be issued.

[0096] Based on the aforementioned surge arrester with self-sensing function, the following steps are specifically adopted when conducting wind-induced vibration condition monitoring and evaluation:

[0097] Step 1: Sensor Installation and Integration

[0098] During the manufacturing process of the surge arrester body 1, a fiber optic grating sensor array is pre-embedded inside the surge arrester body 1 to form an integrated sensor array; then the integrated sensor array is connected to the fiber optic grating demodulator and the data analysis and early warning server in the manner described above.

[0099] Step 2: Data Acquisition and Demodulation

[0100] A broadband light source is emitted to the fiber Bragg grating sensor array through a fiber Bragg grating demodulator, and the reflected light signal is received to demodulate the corresponding wavelength data.

[0101] Step 3: Receive the demodulated wavelength data through the data analysis and early warning server, and perform the following processing:

[0102] a. Calculate the real-time temperature change based on the center wavelength corresponding to the temperature in the strain-free region. The real-time strain value is then temperature-compensated according to the following formula to obtain the compensated real-time strain value. :

[0103] ;

[0104] In the formula: The initial center wavelength of fiber optic strain sensor 2 is given. The amount of drift of the center wavelength of fiber optic strain sensor 2; The thermo-optic coefficient of the optical fiber material; The coefficient of thermal expansion of the optical fiber material; The effective elastic-optical coefficient of the optical fiber material;

[0105] b. The bending moment vector borne by the arrester body 1 is calculated based on the compensated real-time strain value using the following method:

[0106] b.1. Calculate the maximum bending strain amplitude based on the compensated real-time strain value using the following formula. :

[0107] ;

[0108] In the formula: , and These are the real-time strain values ​​after compensation at three different locations;

[0109] b.2 Calculate the bending moment vector borne by the root of the surge arrester body 1 according to the following formula. :

[0110] ;

[0111] In the formula: The elastic modulus of the core material of the surge arrester body; The moment of inertia of the cross section; The distance from the location of fiber optic strain sensor 2 to the neutral axis of the cross section;

[0112] c. Perform a Fast Fourier Transform on the triaxial vibration acceleration according to the following formula to achieve spectral analysis and obtain the spectrum of the resultant horizontal acceleration. Based on the spectrum of the horizontal resultant acceleration. Extract the dominant vibration frequency in real time :

[0113] ;

[0114] d. Using the following method, calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data, and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance:

[0115] d.1. Based on the following formula and real-time wind speed data... and the effective diameter of the surge arrester body 1 Calculate the theoretical frequency of vortex-induced shedding. :

[0116] ;

[0117] In the formula: The Strohar number was calibrated through wind tunnel testing.

[0118] d.2. When the following conditions are met, it is determined to be in a state of vortex-induced resonance:

[0119] and ;

[0120] In the formula: This is the frequency tolerance coefficient, with a value ranging from 0.1 to 0.15; This represents the root mean square value of the triaxial vibration acceleration; The preset acceleration threshold;

[0121] e. Using the following method, rainflow counting is performed on the real-time strain-time history, and the cumulative fatigue damage is calculated by combining the material SN curve and Miner's linear cumulative damage theory:

[0122] e.1. Perform rainflow counting on the real-time strain value-time history to obtain the amplitude of each stress cycle. mean and number of loops The mean stress was corrected using the Goodman formula, and the equivalent stress amplitude was calculated. :

[0123] ;

[0124] In the formula: The ultimate tensile strength of the material; The stress amplitude order;

[0125] e.2. Calculate the first step based on the material's SN curve. Fatigue life corresponding to stress amplitude :

[0126]

[0127] In the formula: These are strength coefficients related to the fatigue strength of materials. The slope parameter of the SN curve is obtained by taking standard fatigue test specimens from the arrester core material and conducting constant amplitude fatigue tests in accordance with relevant national standards such as GB / T 35465.2.

[0128] e.3. Calculate the cumulative fatigue damage degree using Miner's linear cumulative damage theory. :

[0129] ;

[0130] In the formula: This represents the maximum stress amplitude level.

[0131] f. When the cumulative fatigue damage degree When the first preset threshold is reached (in this embodiment, the first preset threshold is 0.8), a warning signal is issued; when the accumulated fatigue damage degree... When the second preset threshold is reached (in this embodiment, the second preset threshold is 1.0), an alarm signal is issued; when it is determined that the state is in vortex-induced resonance, a resonance warning signal is issued.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A surge arrester with self-sensing function, comprising a surge arrester body (1), characterized in that: It also includes fiber Bragg grating sensor arrays, fiber Bragg grating demodulators, and data analysis and early warning servers; The fiber optic grating sensing array is pre-embedded inside the surge arrester body (1) to measure the axial strain distribution of the root section of the surge arrester body (1), the triaxial vibration acceleration of the top of the surge arrester body (1), and the temperature of the strain-free area of ​​the surge arrester body (1). The fiber Bragg grating demodulator is connected to the fiber Bragg grating sensor array via an optical cable. It is used to emit a broadband light source to the fiber Bragg grating sensor array and receive reflected light signals to demodulate the corresponding wavelength data. The data analysis and early warning server is communicatively connected to the fiber optic demodulator and the wind speed sensor installed around the arrester body (1), respectively, to receive the demodulated wavelength data and the measured real-time wind speed data, and to perform the following processing: a. Calculate the real-time strain value based on the axial strain distribution, and perform temperature compensation based on the temperature of the strain-free region; b. Calculate the bending moment vector borne by the arrester body (1) based on the real-time strain value after temperature compensation; c. Perform spectrum analysis based on triaxial vibration acceleration to identify the dominant vibration frequency in real time; d. Calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance. e. Perform rainflow counting on the real-time strain value-time history, and calculate the cumulative fatigue damage degree by combining the material SN curve and Miner's linear cumulative damage theory. f. When the cumulative fatigue damage exceeds the preset threshold, a warning or alarm signal will be issued.

2. A surge arrester with self-sensing function according to claim 1, characterized in that: The fiber grating sensing array includes at least three fiber grating strain sensors (2), at least one fiber grating acceleration sensor (3), and at least one fiber grating temperature sensor; The fiber optic strain sensor (2) is evenly distributed circumferentially on the core surface or metal flange surface of the root section of the surge arrester, and is used to measure the axial strain distribution of the section. The fiber optic accelerometer (3) is installed on the top of the surge arrester to measure the triaxial vibration acceleration of the top of the surge arrester. The fiber optic temperature sensor is installed in the strain-free region of the arrester body (1) to measure the temperature of that region.

3. A surge arrester with self-sensing function according to claim 2, characterized in that: The number of fiber optic strain sensors (2) is three; The fiber optic accelerometer (3) and the fiber optic temperature sensor are both one in number.

4. A surge arrester with self-sensing function according to any one of claims 1-3, characterized in that: The fiber optic grating sensor array is led through the inside of the surge arrester body (1) to the junction box at the bottom of the surge arrester body (1) via a transmission fiber. The junction box is equipped with a fiber optic splicing device for connecting the transmission fiber to the fiber optic grating demodulator via an optical cable.

5. A method for monitoring and evaluating wind-induced vibration conditions, characterized in that, Includes the following steps: Step 1: Sensor Installation and Integration During the manufacturing process of the surge arrester body (1), the fiber optic grating sensor array is pre-embedded inside the surge arrester body (1); then the fiber optic grating sensor array is sequentially connected to the fiber optic grating demodulator and the data analysis and early warning server to form a surge arrester with self-sensing function as described in any one of claims 1-4. Step 2: Data Acquisition and Demodulation A broadband light source is emitted to the fiber Bragg grating sensor array through a fiber Bragg grating demodulator, and the reflected light signal is received to demodulate the corresponding wavelength data. Step 3: Receive the demodulated wavelength data through the data analysis and early warning server, and perform the following processing: a. Calculate the real-time strain value based on the axial strain distribution, and perform temperature compensation based on the temperature of the strain-free region; b. Calculate the bending moment vector borne by the arrester body (1) based on the compensated real-time strain value; c. Perform spectrum analysis based on triaxial vibration acceleration to identify the dominant vibration frequency in real time; d. Calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance. e. Perform rainflow counting on the real-time strain value-time history, and calculate the cumulative fatigue damage degree by combining the material SN curve and Miner's linear cumulative damage theory. f. When the cumulative fatigue damage exceeds the preset threshold, a warning or alarm signal will be issued.

6. The wind-induced vibration condition monitoring and evaluation method according to claim 5, characterized in that, Step 3 specifically involves: a. Calculate the real-time strain value based on the axial strain distribution, and calculate the real-time temperature change based on the center wavelength corresponding to the temperature in the strain-free region. The real-time strain value is then temperature-compensated according to the following formula to obtain the compensated real-time strain value. : ； In the formula: The initial center wavelength of the fiber optic strain sensor (2) is given. The amount of drift of the center wavelength of the fiber optic strain sensor (2); The thermo-optic coefficient of the optical fiber material; The coefficient of thermal expansion of the optical fiber material; The effective elastic-optical coefficient of the optical fiber material; b. The bending moment vector borne by the arrester body (1) is calculated based on the compensated real-time strain value using the following method: b.

1. Based on the compensated real-time strain value, calculate the maximum bending strain amplitude according to the following formula. : ； In the formula: , and These are the real-time strain values ​​after compensation at three different locations; b.

2. Calculate the bending moment vector borne by the root of the surge arrester body (1) according to the following formula. : ； In the formula: The elastic modulus of the core material of the surge arrester body (1); The moment of inertia of the cross section; The distance from the location of the fiber optic strain sensor (2) to the neutral axis of the cross section; c. Perform a Fast Fourier Transform on the triaxial vibration acceleration to achieve spectral analysis and obtain the spectrum of the resultant horizontal acceleration. Furthermore, based on the spectrum of the horizontal resultant acceleration. The real-time dominant vibration frequency is extracted according to the following formula. : ； d. Using the following method, calculate the theoretical frequency of vortex-induced shedding based on real-time wind speed data, and compare it with the real-time dominant vibration frequency to determine whether it is in a state of vortex-induced resonance: d.

1. Based on the following formula and real-time wind speed data... and the effective diameter of the surge arrester body (1) Calculate the theoretical frequency of vortex-induced shedding. : ； In the formula: The Strohar number was calibrated through wind tunnel testing. d.

2. Compare the theoretical frequency of vortex-induced shedding with the real-time dominant vibration frequency. When the following conditions are met, it is determined to be in a state of vortex-induced resonance: and ; In the formula: This is the frequency tolerance coefficient, with a value ranging from 0.1 to 0.15; This represents the root mean square value of the triaxial vibration acceleration; The preset acceleration threshold; e. Using the following method, rainflow counting is performed on the real-time strain-time history, and the cumulative fatigue damage is calculated by combining the material SN curve and Miner's linear cumulative damage theory: e.

1. Perform rainflow counting on the real-time strain value-time history to obtain the amplitude of each stress cycle. mean and number of loops ; The mean stress was corrected using the Goodman formula, and the equivalent stress amplitude was calculated. : ； In the formula: The ultimate tensile strength of the material; The stress amplitude order; e.

2. Calculate the first step based on the material's SN curve. Fatigue life corresponding to stress amplitude : ； In the formula: These are strength coefficients related to the fatigue strength of materials. The slope parameter of the SN curve; e.

3. Calculate the cumulative fatigue damage degree using Miner's linear cumulative damage theory. : ； In the formula: This represents the maximum stress amplitude level. f. When the cumulative fatigue damage degree When the first preset threshold is reached, an early warning signal is issued; When the cumulative fatigue damage When the second preset threshold is reached, an alarm signal is issued; when it is determined that the state is in vortex-induced resonance, a resonance warning signal is issued.

7. The wind-induced vibration condition monitoring and evaluation method according to claim 6, characterized in that: In step 3, the first preset threshold is set to 0.8, and the second preset threshold is set to 1.0.

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