An OPGW optical cable vibration area identification method and system based on wave number domain analysis

Abstract

The application discloses an OPGW cable vibration area identification method and system based on wave number domain analysis, relates to the technical field of optical cable vibration area identification, and aims to solve the problem that the existing OPGW cable vibration measurement method cannot accurately estimate the vibration hidden danger area because it can only measure the instantaneous vibration state. The technical points of the application include: obtaining the strain curve of the fiber core of the OPGW cable to be measured; dividing the strain curve according to the span, and performing wave number domain Fourier transform on the strain signal corresponding to each divided optical cable; using a peak searching algorithm to obtain the maximum value of the wave number domain Fourier transform result, i.e. the strain signal wave number; if there is one or more strain signal wave numbers, it is determined that the optical cable in this span is affected by vibration. The application can identify the vibration hidden danger area of the optical cable in which the internal fiber core strain is abnormal due to long-time vibration, and can provide a strong reference for evaluating the safety condition of the optical cable.

Description

Technical Field

[0001] This invention relates to the field of optical cable vibration region identification technology, specifically to a method and system for identifying vibration regions of OPGW optical cables based on wavenumber domain analysis. Background Technology

[0002] OPGW (Optical Fiber-Coated Wi-Fi) cables play a crucial role as ground wires and information transmission media in power systems. Large-scale construction of OPGW cables began in my country around 2000, with early installations reaching nearly 20 years of service life. The failure rate of these cables has been increasing year by year, seriously threatening the stable operation of the power grid. OPGW cables are subjected to a combination of static and dynamic strain, affecting their fatigue life and reducing the safety of line operation. Static strain in OPGW cables mainly includes tensile strain, residual strain after strand stranding, and bending strain caused by bending. Dynamic strain, caused by vibration in the OPGW cable, is far more harmful than static strain and is the root cause of fiber breakage, strand breakage, and even wire breakage in OPGW cables.

[0003] OPGW optical cables can experience light wind vibrations or galloping under wind conditions. Galloping is a self-excited vibration of low-order natural frequencies generated by overhead transmission lines in strong winds. While the amplitude and frequency of this vibration are usually low, galloping can occur infrequently. However, if it does occur and persists for a long time, it can cause severe wear, breakage, and detachment of hardware, as well as strand breakage and detachment in the overhead line, and line tripping, seriously threatening line safety. Identifying the areas prone to galloping and accurately measuring the half-wavelength of the galloping allows for the installation of anti-galloping devices in targeted sections, reducing safety hazards. Accurate acquisition of the galloping wavelength and frequency provides crucial reference for line safety maintenance. Currently, phase-time domain sensitive meters... It has been used in dynamic frequency monitoring of OPGW optical cable lines to monitor cable vibration. Initial vibrations do not cause significant damage to the line. The fatigue limit of the optical cable is related to the number of vibrations. Long-term accumulated vibration can cause significant deformation at the antinodes of the cable. This is because, under prolonged galloping conditions, the stress on the cable exceeds its elastic limit, leading to plastic deformation and elongation. The cable deformation caused by vibration is the result of accumulated historical conditions. It can only reflect the vibration phenomenon in the current state and cannot give an indication of the impact of the vibration on the optical cable.

[0004] In summary, the existing OPGW optical cable vibration measurement technologies can only measure the instantaneous vibration state and cannot reflect the fatigue stress of the optical cable caused by long-term vibration, nor can they accurately predict the area of ​​potential vibration hazards. Summary of the Invention

[0005] Therefore, the present invention provides a method and system for identifying vibration regions of OPGW optical cables based on wavenumber domain analysis, in an attempt to solve or at least alleviate at least one of the problems mentioned above.

[0006] According to one aspect of the present invention, a method for identifying vibration regions of OPGW optical cables based on wavenumber domain analysis is provided, the method comprising the following steps:

[0007] Step 1: Obtain the strain curve of the OPGW optical fiber core to be tested;

[0008] Step 2: Divide the strain curve according to the span, and perform wavenumber domain Fourier transform on the strain signal corresponding to each span of optical cable.

[0009] Step 3: Use the peak finding algorithm to find the maximum value of the Fourier transform result in the wavenumber domain, that is, to obtain the strain signal wavenumber; if there are one or more strain signal wavenumbers, then it is determined that the optical cable is affected by vibration.

[0010] Furthermore, the specific steps of step one include:

[0011] Step 1: Measure the Brillouin frequency shift data of the fiber core of the OPGW optical cable under test using BOTDR or BOTDA;

[0012] Step 1 and Step 2: Identify the fiber splice points of the OPGW fiber core under test based on the step point differences in the Brillouin frequency shift data of the fiber core under test, locate the splice towers in conjunction with the tower list, and divide the tension sections.

[0013] Step 13: Using each tension section as a calculation unit, calculate the strain value at each point of the OPGW optical fiber core under test according to the following formula, and form a strain curve from the multiple strain values:

[0014]

[0015] In the formula, Strain j This represents the strain value at point j; BFS j Represents the Brillouin shift value at the j-th point; BFS REF This represents the average Brillouin frequency shift at multiple points along the lead-out line; The strain coefficient represents the Brillouin frequency shift.

[0016] Furthermore, in step two, a wavenumber domain Fourier transform is performed according to the following formula:

[0017]

[0018] In the formula, y(x) represents the spatial domain strain signal; Y(k) represents the wavenumber domain strain signal; and k represents the wavenumber of the strain signal.

[0019] Furthermore, it also includes step four: calculating the vibration wavelength based on the strain signal wavenumber; and calculating the installation position of the vibration damper based on the vibration wavelength.

[0020] Furthermore, the vibration wavelength λ is calculated using the following formula:

[0021] λ = 2k.

[0022] Furthermore, if multiple strain signal wavenumbers exist, multiple vibration wavelengths are calculated, and the installation position of the vibration damper is calculated according to the following formula:

[0023]

[0024] In the formula, λ min and λ max These represent the minimum and maximum vibration wavelengths, respectively.

[0025] According to another aspect of the present invention, a vibration region identification system for OPGW optical cables based on wavenumber domain analysis is provided, the system comprising:

[0026] The strain curve acquisition module is configured to acquire the strain curve of the OPGW optical fiber core under test.

[0027] The wavenumber domain transformation module is configured to divide the strain curve according to the span and perform wavenumber domain Fourier transform on the strain signal corresponding to each span of optical cable.

[0028] The vibration area identification module is configured to use a peak-finding algorithm to find the maximum value of the result of the Fourier transform in the wavenumber domain, that is, to obtain the strain signal wavenumber; if there are one or more strain signal wavenumbers, it is determined that the optical cable is affected by vibration.

[0029] Furthermore, the specific steps for obtaining the strain curve of the OPGW optical fiber core under test in the strain curve acquisition module include:

[0030] Step 1: Measure the Brillouin frequency shift data of the fiber core of the OPGW optical cable under test using BOTDR or BOTDA;

[0031] Step 1 and Step 2: Identify the fiber splice points of the OPGW fiber core under test based on the step point differences in the Brillouin frequency shift data of the fiber core under test, locate the splice towers in conjunction with the tower list, and divide the tension sections.

[0032] Step 13: Using each tension section as a calculation unit, calculate the strain value at each point of the OPGW optical fiber core under test according to the following formula, and form a strain curve from the multiple strain values:

[0033]

[0034] In the formula, Strain j This represents the strain value at point j; BFS j Represents the Brillouin shift value at the j-th point; BFS REF This represents the average Brillouin frequency shift at multiple points along the lead-out line; The strain coefficient represents the Brillouin frequency shift.

[0035] Furthermore, the wavenumber domain transformation module performs a wavenumber domain Fourier transform according to the following formula:

[0036]

[0037] In the formula, y(x) represents the spatial domain strain signal; Y(k) represents the wavenumber domain strain signal; and k represents the wavenumber of the strain signal.

[0038] Furthermore, the system also includes a vibration damping installation position calculation module, which is configured to calculate the vibration wavelength based on the strain signal wavenumber and calculate the installation position of the vibration damping hammer based on the vibration wavelength.

[0039] The OPGW optical cable vibration zone identification method and system according to the present invention can achieve at least one of the following beneficial effects:

[0040] (1) Using a distributed Brillouin fiber optic strain monitor to identify vibration areas only requires one static measurement to find the potential vibration area. Due to the presence of excess fiber length in the optical cable, when permanent strain caused by vibration has appeared in the optical cable, it indicates that the line has been subjected to long-term vibration. Measuring the magnitude of the strain caused by vibration is a simple and intuitive way to reflect the impact of vibration. It can assess the vibration fatigue damage of the line, provide a reference for the safety status of the line, facilitate the early detection and elimination of potential hazards, and is easy to operate.

[0041] (2) The method of identifying vibration areas using a distributed Brillouin fiber optic strain monitor only requires one measurement at the station endpoint to determine the safety hazards caused by vibration, without the need to apply additional sensors in the line, making it easy to deploy.

[0042] (3) Using a distributed Brillouin fiber optic strain gauge to identify the vibration region and wavelength, the wavelength is calculated and used to design an anti-vibration scheme, such as adding anti-vibration clamps or protective lines, damping lines, and anti-vibration hammers to prevent and reduce the impact of overhead line vibration. Since the anti-vibration hammer is best installed near the anti-vibration point, the vertical displacement of the hammer is maximized during vibration, and the inertia of the hammer increases the bending degree of the optical cable, which can maximize the absorption of vibration. Attached Figure Description

[0043] Figure 1A flowchart of a vibration region identification method for OPGW optical cables based on wavenumber domain analysis according to an embodiment of the present invention is shown;

[0044] Figure 2 A schematic diagram of the standing wave of an OPGW optical cable according to an embodiment of the present invention is shown;

[0045] Figure 3 The diagram shows the actual field test results and corresponding tower results of measuring the fiber core strain of OPGW optical cable using a distributed Brillouin fiber strain monitor according to an embodiment of the present invention.

[0046] Figure 4 This illustrates an embodiment of the invention using a distributed Brillouin fiber optic strain gauge and wavenumber domain analysis method to obtain... Figure 3 A schematic diagram showing the wave values ​​of the strain curves between towers 166# and 165# shown in the figure;

[0047] Figure 5 An embodiment of the present invention is shown. Figure 3 The wavenumber domain FFT result of the strain curve between towers 165# and 164# is shown in the figure.

[0048] Figure 6 An embodiment of the present invention is shown. Figure 3 The wavenumber domain FFT result of the strain curve between towers 168# and 167# is shown in the figure.

[0049] Figure 7 An embodiment of the present invention is shown. Figure 3 The wavenumber domain FFT result of the strain curve between towers 167# and 166# is shown in the figure.

[0050] Figure 8 A strain map of a volatile region identified using a distributed Brillouin fiber optic strain monitor according to an embodiment of the present invention is shown.

[0051] Figure 9 This illustrates an embodiment of the invention using wavenumber domain FFT and peak-finding algorithms to obtain... Figure 8 The results of the wave numerical values ​​of the medium strain curve are shown in the figure, where the extreme points are the obtained set of wave numerical values ​​K. n . Detailed Implementation

[0052] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0053] This invention provides a method for identifying vibration zones in OPGW optical cables based on a distributed Brillouin fiber optic strain monitor (i.e., Brillouin optical time domain reflectometer - BOTDR or Brillouin optical time domain analyzer - BOTDA) and wavenumber domain analysis. Since the strain generated by the natural vibration of the optical cable reflects the deformation of the optical cable caused by long-term vibration, this method can identify vulnerable areas of the optical cable that are prone to vibration due to abnormal strain in the internal fiber core caused by long-term vibration. Furthermore, by using the strain curve of the optical cable and performing wavenumber domain analysis, the multi-order wavelengths of the optical cable vibration can be obtained, providing a strong reference for assessing the safety status of the optical cable. The accurate solution of the vibration wavelength guides the vibration prevention and control of the line.

[0054] According to one embodiment of the present invention, such as Figure 1 As shown, the method for identifying vibration zones in OPGW optical cables includes the following steps:

[0055] Step 1: Obtain the strain curve of the OPGW optical fiber core to be tested;

[0056] Step 2: Divide the strain curve according to the span, and perform wavenumber domain Fourier transform on the strain signal corresponding to each span of optical cable.

[0057] Step 3: Use the peak finding algorithm to find the maximum value of the Fourier transform result in the wavenumber domain, that is, to obtain the strain signal wavenumber; if there are one or more strain signal wavenumbers, then it is determined that the optical cable is affected by vibration.

[0058] In step one, a distributed Brillouin fiber strain gauge is used to acquire Brillouin frequency shift data of the OPGW fiber core under test. Based on the step point differences in the Brillouin frequency shift data of the OPGW fiber core under test, fiber splice points are identified. The splice towers are located using the tower list, and tension sections are divided. Using each tension section as a calculation unit, the strain values ​​at each point of the OPGW fiber core under test are calculated according to the following formula, and the strain values ​​at multiple points form a strain curve:

[0059]

[0060] In the formula, Strain j This represents the strain value at point j; BFS j Represents the Brillouin shift value at the j-th point; BFS REF This represents the average Brillouin frequency shift value at multiple points along the lead-out line; The strain coefficient represents the Brillouin frequency shift.

[0061] Since the Brillouin frequency shift is affected by both temperature and strain, it can be calculated using the formula based on the Brillouin frequency shift data of a single empty fiber core. The continuous strain curve of the optical fiber core was calculated, with each tension section serving as a calculation unit, and the strain was calculated separately for each section. Since the fiber at the downlead is not subjected to strain and the temperature difference within the tension section is relatively small, the Brillouin frequency shift (BFS) at multiple points at the downlead was averaged. REF The average Brillouin frequency shift at the downlead is used as the reference Brillouin frequency shift, which is treated as the zero-strain reference point. It is assumed that the Brillouin frequency shift is only affected by temperature, and temperature compensation is applied to the optical cable within the tension section. Furthermore, the zero-strain reference point can also be selected as the Brillouin frequency shift value of a flat area within the tension section.

[0062] It should be noted that the method for identifying vibration zones in OPGW optical cables of the present invention is executed in a distributed Brillouin fiber strain monitor. The monitoring device can be a Brillouin optical time domain analyzer (BOTDA) or a Brillouin optical time domain reflectometer (BOTDR), or other terminal devices for measuring the fiber core strain of OPGW optical cables, but is not limited thereto.

[0063] In step two, based on the obtained strain curves, strain regions containing periodic deformation are identified and designated as vibration regions. Furthermore, tower numbers for these abnormal regions can be assigned based on the tower location results. Figure 2 A schematic diagram of a standing wave of an OPGW optical cable according to an embodiment of the present invention is shown, wherein l is the span, α is the vibration angle, point A is the wave node, the wavelength of the standing wave is λ, and points B and C are both antinodes, corresponding to the strain maxima of the strain curve.

[0064] The strain curve is divided into processing units according to each span, and the range of each span is characterized by the fiber length, such as... Figure 3 For a certain tension section shown, the strain curve is divided according to the fiber length of each span; the divided processing units, i.e. the strain signals of each span, are subjected to wavenumber domain Fourier transform (FFT).

[0065] When an OPGW optical cable generates stable vibration, the vibration wave is a standing wave over the entire span. The magnitude of the displacement of the OPGW optical cable from its equilibrium position can be approximated as a sinusoidal change in both span and time. The positions of the wave crests (antinodes) and nodes remain unchanged. The vibration equation at any point x near the outlet of the OPGW optical cable clamp is as follows:

[0066]

[0067] Where y0 is the maximum amplitude, λ n f is the wavelength of the vibration wave. n The inherent frequency of the OPGW is [value]. Here, n represents the wavelength of the vibration wave, l is the span, T0 is the horizontal tension of the OPGW optical cable, and m is the mass per unit length of the OPGW. The natural frequency of the conductor depends only on n, l, T0, and m, and is determined by the system. Different n result in different frequencies f. n The natural frequency is not a single value, but a set of values.

[0068] For a specific time t0, we have The vibration wave exhibits a sinusoidal standing wave distribution along the span, with the positions of the nodes and antinodes remaining unchanged, and its amplitude is y. t =y0sinω n t0. The amplitude of each point on the OPGW optical cable. Performing simple harmonic motion, in At that time, y x =0, that is, the node position, the amplitude is always 0, when At this point, the amplitude reaches its maximum, which is the position of the antinode.

[0069] The repeated cyclic stress on an optical cable is below its ultimate strength level. After a certain number of cycles, cracks or fractures will appear in the structure. Cyclic stress on the optical cable causes permanent loss, i.e., fatigue failure. Prolonged vibration at the natural frequency causes plastic elongation, leading to the depletion of excess fiber core length and strain. The strain is greatest at the antinodes, and the half-wavelength of the vibration can be identified based on the location of the antinodes on the strain curve.

[0070] The strain signal obtained by BOTDR has spatial location information. Let the strain signal in the spatial domain be y(x). Divide the above strain curve into intervals and perform a Fourier transform on it in the spatial direction to realize the conversion of the signal from the spatial domain to the wavenumber domain.

[0071]

[0072] In the formula, k is the strain signal wavenumber, the strain wavenumber is twice the optical cable standing wave number, and the standing wave number of the optical cable vibration curve is k′=k2, where k′=1λ, and λ is the standing wave wavelength.

[0073] In step three, the peak-finding algorithm is used to find the maximum value of the Fourier transform result in each wavenumber domain, that is, to obtain the wavenumber of the strain signal; it is determined whether there is a maximum value. If there is a maximum value, it is determined that the span contains periodic strain and that the optical cable in that span is affected by vibration.

[0074] Furthermore, it also includes step four: calculating the vibration wavelength based on the strain signal wavenumber. The magnitude of the vibration wavelength is λ = 1k′ = 2k. Within a span, the standing wave wavelength of the vibration may not have a single value, but rather a set of values, denoted as λ. n The installation location of the vibration damper is calculated based on the vibration wavelength: the wavelength value λ is obtained from the calculation.n For optical cable vibration damping retrofitting, the optimal installation location for the vibration damper is at the "wave crest" point, where the upward and downward swing amplitude is larger, effectively absorbing the maximum vibration energy. Since the wavelength of overhead line vibration varies with wind speed and stress, within the vibration wind speed range, the wavelength varies between its maximum and minimum values. Therefore, the vibration damper should be installed within the overlapping portion of the maximum and minimum wave nodes, one and a half wavelengths apart. In other words, if multiple strain signal wavenumbers exist, the installation location of the vibration damper is calculated based on the calculated vibration wavelengths using the following formula:

[0075]

[0076] In the formula, λ min and λ max λ represents the minimum and maximum vibration wavelength values, respectively. If only one strain signal wavenumber exists, i.e., only one vibration wavelength is obtained, then λ min =λ max .

[0077] Figure 3 This diagram illustrates the actual field test results of measuring the Brillouin frequency shift of OPGW optical cable cores using a distributed Brillouin fiber strain gauge. The diagram shows the wavenumber domain FFT results for each span obtained from the Brillouin frequency shift and the tower correspondence diagram obtained from the tower details table. Figures 4-7 As shown, it can be seen that Figure 4 (166#-165#) and Figure 5 (165#-164#) is a vibration-prone area. Figure 6 (168#-167#) and Figure 7 (167#-166#) is a non-easily vibrating region. The first extreme value in each figure corresponds to the wave value at zero frequency, not the true wave value, but rather... Figure 4 The strain wave value is 0.0048828, corresponding to a standing wave wavelength of λ = 2k = 2 / 0.0048828 = 409.6m. Figure 5 The strain wave value is 0.0097656, and the corresponding vibration standing wave wavelength is λ=2k=2 / 0.0097656=204.8m. Figure 8 The strain map of a volatile region identified using a distributed Brillouin fiber strain monitor is shown. Figure 9 The image shows the results of obtaining wavenumber values ​​using wavenumber-domain FFT and peak-finding algorithms, where the extreme points are a set of obtained wavenumber values ​​K. n .

[0078] According to another embodiment of the present invention, an OPGW optical cable vibration region identification system based on wavenumber domain analysis includes:

[0079] The strain curve acquisition module is configured to acquire the strain curve of the OPGW optical fiber core under test.

[0080] The wavenumber domain transformation module is configured to divide the strain curve according to the span and perform wavenumber domain Fourier transform on the strain signal corresponding to each span of optical cable.

[0081] The vibration area identification module is configured to use a peak-finding algorithm to find the maximum value of the result of the Fourier transform in the wavenumber domain, that is, to obtain the strain signal wavenumber; if there are one or more strain signal wavenumbers, it is determined that the optical cable is affected by vibration.

[0082] In this embodiment, preferably, the specific steps for obtaining the strain curve of the OPGW optical fiber core under test in the strain curve acquisition module include:

[0083] Step 1: Measure the Brillouin frequency shift data of the fiber core of the OPGW optical cable under test using BOTDR or BOTDA;

[0084] Step 1 and Step 2: Identify the fiber splice points of the OPGW fiber core under test based on the step point differences in the Brillouin frequency shift data of the fiber core under test, locate the splice towers in conjunction with the tower list, and divide the tension sections.

[0085] Step 13: Using each tension section as a calculation unit, calculate the strain value at each point of the OPGW optical fiber core under test according to the following formula, and form a strain curve from the multiple strain values:

[0086]

[0087] In the formula, Strain j This represents the strain value at point j; BFS j Represents the Brillouin shift value at the j-th point; BFS REF This represents the average Brillouin frequency shift at multiple points along the lead-out line; The strain coefficient represents the Brillouin frequency shift.

[0088] In this embodiment, preferably, the wavenumber domain Fourier transform is performed in the wavenumber domain transform module according to the following formula:

[0089]

[0090] In the formula, y(x) represents the spatial domain strain signal; Y(k) represents the wavenumber domain strain signal; and k represents the wavenumber of the strain signal.

[0091] In this embodiment, preferably, the system further includes a vibration damping installation position calculation module, which is configured to calculate the vibration wavelength based on the strain signal wavenumber and calculate the installation position of the vibration damping hammer based on the vibration wavelength.

[0092] The function of the OPGW optical cable vibration region identification system based on wavenumber domain analysis described in this embodiment can be explained by the aforementioned OPGW optical cable vibration region identification method based on wavenumber domain analysis. For parts not described in detail in this embodiment, please refer to the above method embodiments.

[0093] It should be noted that although several units and modules have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of the present invention, the features and functions of two or more modules described above can be embodied in one module. Conversely, the features and functions of one module described above can be further divided and embodied by multiple modules.

[0094] Furthermore, although the operations of the method of the present invention are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0095] While the spirit and principles of the invention have been described with reference to several specific embodiments, it should be understood that the invention is not limited to the disclosed specific embodiments, and the division of aspects does not imply that features in these aspects cannot be combined for benefit; such division is merely for ease of description. The invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. An OPGW optical cable vibration area identification method based on wave number domain analysis, characterized in that, The method comprises the following steps: Step one, obtaining the strain curve of the OPGW optical cable core to be measured; The method comprises: Step one, measuring the Brillouin frequency shift data of the OPGW optical cable core to be measured by using BOTDR or BOTDA; Step two, identifying the fiber splicing point of the OPGW optical cable core to be measured according to the difference of the step points in the Brillouin frequency shift data of the OPGW optical cable core to be measured, positioning the splicing tower in combination with the tower detail table, and dividing the strain section; Step three, taking each strain section as a calculation unit, calculating the strain value of each point of the OPGW optical cable core to be measured according to the following formula, and forming a strain curve with the strain values of multiple points: ； In the formula, denotes the strain value of the jth point; denotes the Brillouin frequency shift value of the jth point; denotes the average value of the multi-point Brillouin frequency shift at the down conductor; denotes the strain coefficient of the Brillouin frequency shift; Step two, dividing the strain curve according to the span, and performing wave number domain Fourier transform on the strain signal corresponding to each divided optical cable; wherein the wave number domain Fourier transform is performed according to the following formula: ； wherein represents a spatial domain strain signal; represents a wave number domain strain signal; represents a strain signal wave number; Step three, using a peak searching algorithm to find the maximum value of the result of the wave number domain Fourier transform, i.e. obtaining the strain signal wave number; if there is one or more strain signal wave numbers, it is determined that the optical cable of this span is affected by vibration.

2. The OPGW cable vibration area identification method based on wave number domain analysis according to claim 1, characterized in that, The method further comprises step four, calculating the vibration wavelength according to the strain signal wave number; and calculating the installation position of the anti-vibration hammer according to the vibration wavelength.

3. The OPGW cable vibration area identification method based on wave number domain analysis according to claim 2, characterized in that, The vibration wavelength is calculated according to the following formula : ； In the formula, represents the number of strain signal waves.

4. The OPGW cable vibration area identification method based on wave number domain analysis according to claim 2, characterized in that, If there are multiple strain signal wave numbers in step four, multiple vibration wavelengths are calculated, and the installation position of the anti-vibration hammer is calculated according to the following formula: ； wherein and respectively represent the minimum value of the vibration wavelength and the maximum value of the vibration wavelength.

5. An OPGW optical cable vibration area identification system based on wave number domain analysis, characterized in that, The method comprises: A strain curve acquisition module configured to obtain the strain curve of the OPGW optical cable core to be measured; The method comprises: Step one, measuring the Brillouin frequency shift data of the OPGW optical cable core to be measured by using BOTDR or BOTDA; Step two, identifying the fiber splicing point of the OPGW optical cable core to be measured according to the difference of the step points in the Brillouin frequency shift data of the OPGW optical cable core to be measured, positioning the splicing tower in combination with the tower detail table, and dividing the strain section; Step three, taking each strain section as a calculation unit, calculating the strain value of each point of the OPGW optical cable core to be measured according to the following formula, and forming a strain curve with the strain values of multiple points: ； In the formula, denotes the strain value of the jth point; denotes the Brillouin frequency shift value of the jth point; denotes the average value of the Brillouin frequency shift at multiple points of the down conductor; denotes the strain coefficient of the Brillouin frequency shift; A wave number domain transform module configured to divide the strain curve according to the span, and perform wave number domain Fourier transform on the strain signal corresponding to each divided optical cable; wherein the wave number domain Fourier transform is performed according to the following formula: ； wherein represents a spatial domain strain signal; represents a wave number domain strain signal; represents a strain signal wave number; A vibration area identification module configured to use a peak searching algorithm to find the maximum value of the result of the wave number domain Fourier transform, i.e. obtaining the strain signal wave number; if there is one or more strain signal wave numbers, it is determined that the optical cable of this span is affected by vibration.

6. The OPGW cable vibration area identification system based on wave number domain analysis according to claim 5, characterized in that, The system further comprises an anti-vibration installation position calculation module configured to calculate the vibration wavelength according to the strain signal wave number, and calculate the installation position of the anti-vibration hammer according to the vibration wavelength.

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