Optical fiber cable insulation damage positioning method

Abstract

The present application belongs to the technical field of optical fiber cable detection, and particularly relates to a method for positioning insulation damage of an optical fiber cable, which comprises: applying pressure to a conductive copper tube of the optical fiber cable, and collecting a time-space two-dimensional distribution vibration signal diagram of the optical fiber cable; when a certain sensing channel area on the signal diagram repeatedly appears an impulse abnormal signal group in the time dimension, the impulse abnormal signal group appearing each time presents a bidirectional propagation characteristic occurring with time in the space dimension, and the voltage on the conductive copper tube suddenly drops each time the impulse abnormal signal group appears, then a space position area of the optical fiber cable corresponding to the certain sensing channel area is an abnormal partial discharge area; in the impulse abnormal signal group appearing each time, a space position area corresponding to a sensing channel in which the impulse abnormal signal first appears is locked as an abnormal partial discharge signal occurrence area, and the positioning error is less than the sensing channel length. The present application can accurately realize long-distance distributed insulation damage positioning of the optical fiber cable.

Description

Technical Field

[0001] This invention belongs to the technical field of optical-electric composite cable detection, and more specifically, relates to a method for locating insulation damage in optical-electric composite cables. Background Technology

[0002] Optical fiber composite cables are composite cables integrating optical fibers and copper conductors, used to simultaneously transmit optical and electrical signals. With the rapid development of optical communication technology, the application of optical fiber composite cables is increasing, especially in transoceanic submarine communication networks. However, with increasing usage time and unreliable construction, the internal insulation of optical fiber composite cables gradually deteriorates, eventually developing into permanent faults, leading to localized abnormal discharges and severely affecting their normal operation for carrying out routine services. Therefore, the detection and localization of internal insulation problems in optical fiber composite cables will become an urgent need for future economic development.

[0003] Given the unique characteristics of long-distance deployment of fiber optic composite cables, especially the large-capacity submarine fiber optic composite cables currently used for power transmission in offshore wind power, conventional partial discharge detection methods and equipment are relatively difficult to use. Furthermore, the various influences caused by the excessive length of the fiber optic composite cable on the detection signals significantly reduce the detection effectiveness. For example, existing traditional electrical detection schemes typically use the traveling wave method to determine the location of partial discharge in the cable. However, due to the attenuation of the discharge pulse during cable transmission, positioning errors exist, making it impossible to locate partial discharges over long distances.

[0004] In addition, considering that partial discharge in the optical-electric composite cable will generate a spectral distribution of 10 to 10, 7 Since Hz sound waves are generated, some studies have explored using sound signals generated by partial discharge to reflect the condition of the partial discharge. However, traditional ultrasonic detection is mostly achieved through piezoelectric ceramic sensors, which makes it difficult to perform distributed detection of long-distance underwater optical-electric composite cables. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a method for locating insulation damage in optoelectronic composite cables, the purpose of which is to accurately locate insulation damage in optoelectronic composite cables over long distances in a distributed manner.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for locating insulation damage in an optoelectronic composite cable is provided, comprising:

[0007] A continuous pressure is applied to the conductive copper tube of the optoelectronic composite cable under test. A two-dimensional spatiotemporal distribution vibration signal map of the optoelectronic composite cable is acquired in real time using fiber optic distributed acoustic wave sensing. When a certain sensing channel region on the two-dimensional spatiotemporal distribution vibration signal map repeatedly exhibits impulse abnormal signal groups in the time dimension, and each impulse abnormal signal group shows bidirectional propagation characteristics over time in the spatial dimension, and the voltage on the conductive copper tube suddenly drops each time an impulse abnormal signal group appears, then each impulse abnormal signal group is identified as an abnormal partial discharge signal group; the spatial location region of the optoelectronic composite cable corresponding to the certain sensing channel region is the abnormal partial discharge region.

[0008] In any given set of impulse abnormal signals, based on the bidirectional propagation characteristics, the spatial location region of the optoelectronic composite cable corresponding to the sensing channel that first exhibits the impulse abnormal signal is further identified. This region is used as the abnormal partial discharge signal occurrence area of ​​the abnormal partial discharge region, which is the preliminary location of the insulation damage location of the optoelectronic composite cable to be detected. The positioning error is less than the sensing channel length L. S .

[0009] Furthermore, the fiber-optic distributed acoustic wave sensing system is connected to any fiber core of the optoelectronic composite cable to be tested. The fiber-optic distributed acoustic wave sensing system collects the backscattered light signal of that fiber core and demodulates it to obtain the spatiotemporal two-dimensional distributed vibration signal map.

[0010] Furthermore, after coarse positioning, it also includes:

[0011] In a two-dimensional spatiotemporal distribution vibration signal map, an abnormal signal containing any abnormal partial discharge signal group is extracted from a certain sensing channel region. The duration of the abnormal signal is longer than the occurrence duration of the abnormal partial discharge signal group and covers the signal before the occurrence of the abnormal partial discharge signal group. A time sampling window of a preset size is used, with a sliding step size of 1 time sampling interval. The data of each sensing channel is slid-sampled in the extracted abnormal signal. A short-time Fourier transform is performed on the short-time signal frame obtained from each sampling of the sensing channel to obtain a frequency domain energy distribution.

[0012] Take any one sensing channel in a certain sensing channel region, perform a Fourier transform on the abnormal partial discharge signal of the sensing channel in any abnormal partial discharge signal group, and take the obtained frequency domain distribution characteristics as the frequency domain distribution characteristics of the abnormal partial discharge signal group in the certain sensing channel region; determine the continuous frequency domain range of the superimposed power density spectrum based on the frequency domain distribution characteristics, and calculate the energy of the frequency domain distribution characteristics within the continuous frequency domain range.

[0013] The power density spectrum of each frequency domain energy distribution is superimposed within a continuous frequency domain to obtain the energy of the short-time signal frame corresponding to that frequency domain energy distribution. The energy of all short-time signal frames corresponding to each sensing channel in a certain sensing channel region is used to construct an energy spectrum in time. The energy spectrum of the reference sensing channel and the energy spectra of other sensing channels in the certain sensing channel region are respectively delayed to obtain the delay τ of the abnormal local signal occurrence of other sensing channels relative to the reference sensing channel. The reference sensing channel is the sensing channel in which the abnormal partial discharge signal first appears in the abnormal partial discharge signal group selected during the short-time Fourier transform.

[0014] Construct distance and delay data pairs (X+(a-1)L) S ,τ -a ), ..., (X,τ -1 ), (L S -X,τ +1 ), ..., (bL S -X,τ +b ), where X represents the assumed precise discharge location at a distance from the starting point of the reference sensing channel; 0 ≤ X ≤ sensing channel length L S ;X+(a-1)L S bL represents the distance between the a-th adjacent sensing channel preceding the reference sensing channel and the precise discharge position. S -X represents the distance between the b-th adjacent sensing channel following the reference sensing channel and the precise discharge location; τ -a τ represents the delay in the occurrence of abnormal local signals in the a-th sensing channel relative to the reference sensing channel; +b This represents the delay in the occurrence of abnormal local signals in the b-th sensing channel relative to the reference sensing channel; within 0 to L S Within the range X, perform linear fitting on the distance and delay data pair for each current X, and take the X corresponding to the smallest fitting error as the fine position of the abnormal partial discharge signal on the reference sensing channel.

[0015] Furthermore, a Fourier transform is performed on the first abnormal partial discharge signal in any abnormal partial discharge signal group of the selected sensing channel, and the resulting frequency domain distribution characteristics are used as the frequency domain distribution characteristics of the abnormal partial discharge signal group of the certain sensing channel region.

[0016] Furthermore, generalized cross-correlation is used for delay calculation.

[0017] Furthermore, based on this frequency domain distribution characteristic, multiple continuous frequency domain ranges Fr for the superposition of power density spectra are determined. i And calculate Fr for each continuous frequency range. iEnergy Pr of internal frequency domain distribution characteristics i ;

[0018] Fr in each continuous frequency domain i Next, calculate the delay τ of abnormal local signals occurring in each of the other sensing channels relative to the reference sensing channel. i ;

[0019] For each continuous frequency range Fr i Construct distance and latency data pairs Among them, X i Fr represents the continuous frequency domain range i The assumed precise discharge location is the distance from the starting point of the reference sensing channel; 0 ≤ X i ≤Sensing channel length L S ;X i +(a-1)L S bL represents the distance between the a-th adjacent sensing channel preceding the reference sensing channel and the precise discharge position. S -X i This represents the distance between the b-th adjacent sensing channel following the reference sensing channel and the precise discharge location; Fr represents the continuous frequency domain range i The following describes the delay in the occurrence of abnormal local signals in the a-th sensing channel relative to the reference sensing channel; Fr represents the continuous frequency domain range i The delay of the abnormal local signal occurrence of the b-th sensing channel relative to the reference sensing channel; in the range of 0 to L S Traverse X within the range i In each current X that is traversed i Next, a linear fit is performed on the distance and delay data pair, and the X corresponding to the minimum fitting error is selected. i As Fr passes through the continuous frequency domain range i The precisely determined location of the abnormal partial discharge signal on the reference sensing channel;

[0020] All continuous frequency domain ranges Fr i The X corresponding to the minimum fitting error i The average value is taken as the final precise location.

[0021] Furthermore, the step of combining all continuous frequency domain ranges Fr i The X corresponding to the minimum fitting error i The method for taking the average is as follows:

[0022]

[0023] In the formula, Fr represents the continuous frequency domain range i The X corresponding to the minimum fitting error i .

[0024] According to another aspect of the present invention, an electronic device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the steps of the method described above.

[0025] According to another aspect of the invention, a computer-readable storage medium is provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is run by a processor, it controls the device where the storage medium is located to perform the steps of the method described above.

[0026] According to another aspect of the invention, a computer program product is provided, comprising a computer program or instructions that, when executed by a processor, implement the steps of the method described above.

[0027] In summary, compared with the prior art, the technical solutions conceived by this invention have the following main advantages:

[0028] 1. This invention provides a method for locating insulation damage in fiber optic composite cables. It utilizes fiber-optic distributed acoustic sensing to detect vibrations generated by discharge at the location of insulation damage. When a sensing channel region on a two-dimensional spatiotemporal vibration signal map repeatedly exhibits impulse abnormal signal groups in the time dimension, and each impulse abnormal signal group displays bidirectional propagation characteristics over time in the spatial dimension, with a sudden voltage drop on the conductive copper tube at each occurrence, then each impulse abnormal signal group is identified as an abnormal partial discharge signal group. The spatial location region of the fiber optic composite cable corresponding to a certain sensing channel region is the abnormal partial discharge region. By utilizing the bidirectional propagation characteristic of the discharge vibration signal, the location of the insulation damage in the fiber optic composite cable can be initially located based on the position where the signal first appears. This invention, based on this method, can accurately achieve the initial location of insulation damage, providing reliable information for repair and greatly improving repair efficiency. Moreover, this invention only requires testing at one end of the submarine optical cable, making it convenient and highly operable.

[0029] 2. Furthermore, this invention proposes a method for precise location of discharge signals based on propagation delay. By extracting the distributed discharge signal collected by the fiber optic distributed acoustic wave sensing system, frequency domain energy is used to accurately estimate the delay, solving the problem of large errors when using time-domain signals for cross-correlation when signal waveforms are inconsistent. By segmenting different frequency domains, errors caused by inconsistent propagation speeds of signals at different frequencies can be reduced. Finally, the final location is calculated based on power weighting of the positions obtained from multiple frequency bands, achieving high accuracy and sub-meter precision. This method can provide precise fault location for subsequent repairs of damaged optical fiber composite cable insulation, improving repair efficiency. Attached Figure Description

[0030] Figure 1 A flowchart illustrating a method for locating insulation damage in an optoelectronic composite cable, provided in an embodiment of the present invention.

[0031] Figure 2 This is a spatiotemporal two-dimensional distribution vibration signal diagram provided in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of a spatiotemporal two-dimensional distribution vibration signal acquisition device provided in an embodiment of the present invention;

[0033] Figure 4 A cross-sectional view of the optoelectronic composite cable to be tested provided in an embodiment of the present invention;

[0034] Figure 5 A schematic diagram of linear fitting of all delays of the abnormal partial discharge signal provided in an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of two-dimensional spatial positioning using a multi-sensor array provided in an embodiment of the present invention;

[0036] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0037] 1 is the fiber optic distributed acoustic wave sensing system; 2 is the optical-electric composite cable under test; 2-1 is the conductive copper tube; 2-2 is the optical fiber tube; 3 is the abnormal signal; 3-1 is the abnormal partial discharge region; 4 is the energy spectrum; 5 is the third sensing channel after the reference sensing channel and its delay with the reference sensing channel; 6 is the reference sensing channel; 7 is the backward propagation direction of the abnormal partial discharge signal; 8 is the forward propagation direction of the abnormal partial discharge signal. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0039] Example 1

[0040] A method for locating insulation damage in an optical-electric composite cable, such as Figure 1 As shown, it includes:

[0041] The conductive copper tube of the optoelectronic composite cable under test is continuously pressurized, and the spatiotemporal two-dimensional distribution vibration signal map of the optoelectronic composite cable is collected in real time through fiber optic distributed acoustic wave sensing.

[0042] When a certain sensing channel region (e.g.) is displayed on a two-dimensional spatial-temporal distribution vibration signal map. Figure 2 As shown in the diagram, if the impulsive abnormal signal group repeatedly appears in the time dimension, and each impulsive abnormal signal group exhibits bidirectional propagation characteristics over time in the spatial dimension, and the voltage on the conductive copper tube suddenly drops each time the impulsive abnormal signal group appears, then each impulsive abnormal signal group is identified as an abnormal partial discharge signal group; the spatial location area of ​​the optoelectronic composite cable corresponding to a certain sensing channel area is the abnormal partial discharge area.

[0043] In any given set of impulse abnormal signals, based on the bidirectional propagation characteristics, the spatial location region of the optoelectronic composite cable corresponding to the sensing channel that first exhibits the impulse abnormal signal is further identified. This region is used as the abnormal partial discharge signal occurrence area of ​​the abnormal partial discharge region, which is the coarse location of the insulation damage position of the optoelectronic composite cable to be detected. The location error is less than the sensing channel length L. S .

[0044] This embodiment utilizes fiber optic distributed acoustic sensing to detect vibrations generated by discharge at the location of insulation damage, thereby achieving coarse localization of the insulation damage location. The test only needs to be performed at one end of the submarine optical cable.

[0045] As a preferred option, the fiber-optic distributed acoustic wave sensing system can be connected to any fiber core of the optoelectronic composite cable to be tested. The fiber-optic distributed acoustic wave sensing system can collect the backscattered light signal of the fiber core and demodulate it to obtain the spatiotemporal two-dimensional distributed vibration signal map.

[0046] For example, such as Figure 3 and Figure 4As shown, the phase-sensitive optical time-domain reflectometer 1 of the fiber optic distributed acoustic wave sensing system is connected to any core fiber in the optical fiber tube 2-2 of the optical fiber composite cable 2 to be tested; the conductive copper tube 2-1 of the optical fiber composite cable to be tested is pressurized until partial discharge occurs; the phase-sensitive optical time-domain reflectometer 1 monitors the distributed vibration signal of the optical fiber composite cable in real time during the pressurization process with a spatial resolution of 10m and a sampling rate of 2000Hz (example, set according to the specific situation, the length of the composite cable, etc.).

[0047] The phase-sensitive optical time-domain reflectometer 1 monitors the distributed vibration signal of the optoelectronic composite cable in real time during the pressurization process. Specifically, this involves continuously increasing the voltage applied to the conductive copper tube 2-1 of the optoelectronic composite cable under test, and continuously monitoring the temporal-spatial two-dimensional distribution signal map (i.e., the distributed vibration signal) output by the phase-sensitive optical time-domain reflectometer 1. This continues until a set of impulse-like abnormal signals repeatedly appears in the time domain at a certain position on the temporal-spatial two-dimensional distribution signal map, exhibiting bidirectional propagation characteristics in space. Each time this impulse-like abnormal signal set appears, the voltage on the conductive copper tube 2-1 of the optoelectronic composite cable under test suddenly drops. When both conditions are met simultaneously, the impulse-like abnormal signal set is identified as an abnormal partial discharge signal set.

[0048] The spatial location of the optoelectronic composite cable corresponding to the sensing channel area where the abnormal partial discharge signal group is detected is the abnormal partial discharge region. According to the propagation characteristics, the spatial location of the optoelectronic composite cable corresponding to the sensing channel where the abnormal partial discharge signal first appears is the approximate location of the abnormal partial discharge signal (i.e., preliminary location), which is the preliminary location of the insulation damage location of the optoelectronic composite cable to be tested. The location error is less than the sensing channel length L. S .

[0049] In this implementation case, the phase-sensitive optical time-domain reflectometer 1 is connected to the optical fiber of the optical-electric composite cable, which is arranged in a straight line in the optical fiber tube 2-2 inside the optical-electric composite cable 2.

[0050] As a preferred implementation method, after coarse positioning, it further includes:

[0051] Extract the abnormal signal (e.g., any abnormal partial discharge signal group) from a certain sensing channel region in the spatiotemporal two-dimensional distributed vibration signal map. Figure 2 As shown in the label 3), the duration of the abnormal signal is longer than the duration of the abnormal partial discharge signal group and covers the signal before the occurrence of the abnormal partial discharge signal group; a time sampling window of a preset size is used, with a sliding step of 1 time sampling interval, and the data of each sensing channel in the extracted abnormal signal is slid sampled, and a short-time Fourier transform is performed on the short-time signal frame obtained by each sampling of the sensing channel to obtain a frequency domain energy distribution.

[0052] Take any one sensing channel in a certain sensing channel region, perform a Fourier transform on the abnormal partial discharge signal of the sensing channel in any abnormal partial discharge signal group, and take the obtained frequency domain distribution characteristics as the frequency domain distribution characteristics of the abnormal partial discharge signal group in the certain sensing channel region; determine the continuous frequency domain range of the superimposed power density spectrum based on the frequency domain distribution characteristics, and calculate the energy of the frequency domain distribution characteristics within the continuous frequency domain range.

[0053] Power density spectra of each frequency domain energy distribution are superimposed within a continuous frequency domain to obtain the energy of the short-time signal frame corresponding to that frequency domain energy distribution. The energy of all short-time signal frames corresponding to each sensing channel in a certain sensing channel region is then used to construct an energy spectrum over time. The energy spectrum of the reference sensing channel and the energy spectra of other sensing channels in the same sensing channel region are then subjected to delay calculations to obtain the delay τ (e.g., the delay of abnormal local signals in other sensing channels relative to the reference sensing channel). Figure 5 The rising edge of the abnormal signal of each channel within the marked 4 is shown; wherein, the reference sensing channel is the sensing channel in the abnormal partial discharge signal group selected during the short-time Fourier transform that first shows an abnormal partial discharge signal.

[0054] Construct distance and delay data pairs (X+(a-1)L) S ,τ -a ), ..., (X,τ -1 ), (L S -X,τ +1 ), ..., (bL S -X,τ +b ), where X represents the assumed precise discharge location at a distance from the starting point of the reference sensing channel; 0 ≤ X ≤ sensing channel length L S ;X+(a-1)L S bL represents the distance between the a-th adjacent sensing channel preceding the reference sensing channel and the precise discharge position. S -X represents the distance between the b-th adjacent sensing channel following the reference sensing channel and the precise discharge location; τ -a τ represents the delay in the occurrence of abnormal local signals in the a-th sensing channel relative to the reference sensing channel; +b This represents the delay in the occurrence of abnormal local signals in the b-th sensing channel relative to the reference sensing channel; within 0 to L S Within the range X, perform linear fitting on the distance and delay data pair for each current X, and take the X corresponding to the smallest fitting error as the fine position of the abnormal partial discharge signal on the reference sensing channel.

[0055] like Figure 6As shown, the red star represents the precise discharge location X, traversing the vertical direction between the two red dashed lines. 6 represents the reference sensing channel, 5 represents the third sensing channel after the reference sensing channel and its communication delay with the reference sensing channel, 7 represents the backward propagation direction of the abnormal partial discharge signal, and 8 represents the forward propagation direction of the abnormal partial discharge signal.

[0056] In this implementation case, the short-time Fourier transform steps of the local area discharge signal are as follows: the data of all sensing channels containing the abnormal signal group are subjected to short-time Fourier transform with 100 time-sampled data to obtain a frequency domain energy distribution (for the same time window, each sensing channel corresponds to a frequency domain energy distribution), and the short-time signal frame of 100 time-sampled data is moved by only one time sampling interval each time.

[0057] In addition, for example, if a wide frequency distribution is observed within 1000Hz, the superimposed frequency domain range of the power density spectrum can be determined to be 0 to 1000Hz.

[0058] In this preferred embodiment, the final accurate location result of the abnormal discharge signal is the position X corresponding to the minimum fitting error, with an accuracy of sub-meter level. The positioning error is much smaller than the spatial resolution of the phase-sensitive optical time-domain reflectometer.

[0059] Preferably, the frequency domain distribution characteristics obtained by performing a Fourier transform on the first abnormal partial discharge signal in any abnormal partial discharge signal group of the selected sensing channel are used as the frequency domain distribution characteristics of the abnormal partial discharge signal group of the certain sensing channel region.

[0060] As a preferred method, generalized cross-correlation can be used for delay calculation.

[0061] Preferably, multiple continuous frequency ranges Fr for the superposition of power density spectra can be determined based on the frequency domain distribution characteristics. i And calculate Fr for each continuous frequency range. i Energy Pr of internal frequency domain distribution characteristics i ;

[0062] Fr in each continuous frequency domain i Next, calculate the delay τ of abnormal local signals occurring in each of the other sensing channels relative to the reference sensing channel. i ;

[0063] For each continuous frequency range Fr i Construct distance and latency data pairs Among them, X i Fr represents the continuous frequency domain range iThe assumed precise discharge location is the distance from the starting point of the reference sensing channel; 0 ≤ X i ≤Sensing channel length L S ;X i +(a-1)L S bL represents the distance between the a-th adjacent sensing channel preceding the reference sensing channel and the precise discharge position. S -X i This represents the distance between the b-th adjacent sensing channel following the reference sensing channel and the precise discharge location; Fr represents the continuous frequency domain range i The following describes the delay in the occurrence of abnormal local signals in the a-th sensing channel relative to the reference sensing channel; Fr represents the continuous frequency domain range i The delay of the abnormal local signal occurrence of the b-th sensing channel relative to the reference sensing channel; in the range of 0 to L S Traverse X within the range i In each current X that is traversed i Next, a linear fit is performed on the distance and delay data pair, and the X corresponding to the minimum fitting error is selected. i As Fr passes through the continuous frequency domain range i The precisely determined location of the abnormal partial discharge signal on the reference sensing channel;

[0064] All continuous frequency domain ranges Fr i The X corresponding to the minimum fitting error i The average value is taken as the final precise location.

[0065] Preferably, the step of combining all continuous frequency domain ranges Fr i The X corresponding to the minimum fitting error i The method for taking the average is as follows:

[0066]

[0067] In the formula, Fr represents the continuous frequency domain range i The X corresponding to the minimum fitting error i .

[0068] Example 2

[0069] This application also relates to an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0070] The electronic device can be a desktop computer, laptop, handheld computer, or cloud server, etc. The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The memory can be used to store computer programs and / or modules. The processor performs various functions of the electronic device by running or executing the computer programs and / or modules stored in the memory, and by accessing data stored in the memory.

[0071] The relevant technical solutions are the same as above, and will not be repeated here.

[0072] Example 3

[0073] This application also relates to a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described above.

[0074] Specifically, the memory may include high-speed random access memory, as well as non-volatile memory, such as hard disks, RAM, plug-in hard disks, smart media cards (SMC), secure digital cards (SD), flash cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0075] The relevant technical solutions are the same as above, and will not be repeated here.

[0076] Example 4

[0077] This application provides a computer program product or computer program that includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the steps of the method described in the above embodiments of this application.

[0078] The relevant technical solutions are the same as above, and will not be repeated here.

[0079] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for locating insulation damage in an optoelectronic composite cable, characterized in that, include: A continuous pressure is applied to the conductive copper tube of the optoelectronic composite cable under test. A two-dimensional spatiotemporal distribution vibration signal map of the optoelectronic composite cable is acquired in real time using fiber optic distributed acoustic wave sensing. When a certain sensing channel region on the two-dimensional spatiotemporal distribution vibration signal map repeatedly exhibits impulse abnormal signal groups in the time dimension, and each impulse abnormal signal group shows bidirectional propagation characteristics over time in the spatial dimension, and the voltage on the conductive copper tube suddenly drops each time an impulse abnormal signal group appears, then each impulse abnormal signal group is identified as an abnormal partial discharge signal group; the spatial location region of the optoelectronic composite cable corresponding to the certain sensing channel region is the abnormal partial discharge region. In any given set of impulse abnormal signals, based on the bidirectional propagation characteristics, the spatial location region of the optoelectronic composite cable corresponding to the sensing channel that first exhibits the impulse abnormal signal is further identified. This region is used as the abnormal partial discharge signal occurrence area of ​​the abnormal partial discharge region, which is the preliminary location of the insulation damage location of the optoelectronic composite cable to be detected. The positioning error is less than the sensing channel length L. S ; Following the initial positioning, this also includes: In a two-dimensional spatiotemporal distribution vibration signal map, an abnormal signal containing any abnormal partial discharge signal group is extracted from a certain sensing channel region. The duration of the abnormal signal is longer than the occurrence duration of the abnormal partial discharge signal group and covers the signal before the occurrence of the abnormal partial discharge signal group. A time sampling window of a preset size is used, with a sliding step size of 1 time sampling interval. The data of each sensing channel is slid-sampled in the extracted abnormal signal. A short-time Fourier transform is performed on the short-time signal frame obtained from each sampling of the sensing channel to obtain a frequency domain energy distribution. Take any one sensing channel in a certain sensing channel region, and perform a Fourier transform on the abnormal partial discharge signal of that sensing channel in any abnormal partial discharge signal group. ， The obtained frequency domain distribution characteristics are used as the frequency domain distribution characteristics of the abnormal partial discharge signal group in a certain sensing channel region; the continuous frequency domain range of the power density spectrum superposition is determined based on the frequency domain distribution characteristics, and the energy of the frequency domain distribution characteristics within the continuous frequency domain range is calculated; Power density spectra of each frequency domain energy distribution are superimposed within a continuous frequency domain to obtain the energy of the short-time signal frame corresponding to that frequency domain energy distribution. The energy of all short-time signal frames corresponding to each sensing channel in a certain sensing channel region is then used to construct an energy spectrum over time. The energy spectrum of the reference sensing channel and the energy spectra of other sensing channels in the same sensing channel region are then subjected to delay calculations to obtain the delay of abnormal local signals occurring in other sensing channels relative to the reference sensing channel. The reference sensing channel is the sensing channel that first exhibits an abnormal partial discharge signal in the abnormal partial discharge signal group selected during the short-time Fourier transform. Construct distance and latency data pairs , ..., , ……, ,in, This represents the distance of the assumed precise discharge location from the starting point of the reference sensing channel; 0 ≤ ≤Sensor channel length ; Indicates the number of adjacent channels before the reference sensor channel. The distance between each sensing channel and the precise discharge location Indicates the number of adjacent channels after the reference sensor channel. The distance between each sensing channel and the precise discharge location; Indicates the first The delay of abnormal local signals occurring in each sensing channel relative to the reference sensing channel; Indicates the first The delay of abnormal local signals occurring in each sensing channel relative to the reference sensing channel; in 0~ Traversal within range In each current iteration Next, a linear fit is performed on the distance and delay data pairs, and the data with the smallest fitting error is selected. This serves as the precise location of the anomalous partial discharge signal on the reference sensing channel.

2. The method for locating insulation damage in an optoelectronic composite cable as described in claim 1, characterized in that, The fiber-optic distributed acoustic wave sensing system is connected to any fiber core of the optoelectronic composite cable to be tested. The fiber-optic distributed acoustic wave sensing system collects the backscattered light signal of that fiber core and demodulates it to obtain the spatiotemporal two-dimensional distributed vibration signal map.

3. The method for locating insulation damage in an optoelectronic composite cable as described in claim 1, characterized in that, Fourier transform is performed on the first abnormal partial discharge signal appearing in any abnormal partial discharge signal group of the selected sensing channel. ， The obtained frequency domain distribution characteristics are used as the frequency domain distribution characteristics of the abnormal partial discharge signal group in a certain sensing channel region.

4. The method for locating insulation damage in an optoelectronic composite cable as described in claim 1, characterized in that, Generalized cross-correlation is used for delay calculation.

5. The method for locating insulation damage in an optoelectronic composite cable as described in claim 1, characterized in that, Based on this frequency domain distribution characteristic, determine multiple continuous frequency domain ranges of the superimposed power density spectrum. ; And calculate each continuous frequency range Energy distribution characteristics in the internal frequency domain ; In each continuous frequency domain range Next, calculate the delay of abnormal local signals occurring in each of the other sensing channels relative to the reference sensing channel. ; For each continuous frequency range Construct distance and latency data pairs , ..., , ……, ,in, Indicates the range of continuous frequency domain The assumed precise discharge location is the distance from the starting point of the reference sensing channel; 0 ≤ ≤Sensor channel length ; Indicates the number of adjacent channels before the reference sensor channel. The distance between each sensing channel and the precise discharge location Indicates the number of adjacent channels after the reference sensor channel. The distance between each sensing channel and the precise discharge location; Indicates the range of continuous frequency domain The following is the first The delay of abnormal local signals occurring in each sensing channel relative to the reference sensing channel; Indicates the range of continuous frequency domain The following is the first The delay of abnormal local signals occurring in each sensing channel relative to the reference sensing channel; in 0~ Traversal within range In each current iteration Next, a linear fit is performed on the distance and delay data pairs, and the data with the smallest fitting error is selected. As through the continuous frequency domain range The precisely determined location of the abnormal partial discharge signal on the reference sensing channel; All continuous frequency domain range The minimum fitting error corresponds to The average value is taken as the final precise location.

6. The method for locating insulation damage in an optoelectronic composite cable as described in claim 5, characterized in that, The term encompasses all continuous frequency domain ranges The minimum fitting error corresponds to The method for taking the average is as follows: In the formula, Indicates the range of continuous frequency domain The minimum fitting error corresponds to .

7. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein the computer program, when executed by a processor, controls the device on which the storage medium is located to perform the steps of the method as described in any one of claims 1 to 6.

9. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by a processor, they implement the steps of the method as described in any one of claims 1 to 6.

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