Method, system and device for analyzing motion state of excitation source based on distributed optical fiber

Abstract

This application discloses a method, system, and device for analyzing the motion state of an excitation source based on distributed optical fiber. The method includes: acquiring vibration excitation signals from all detection points on a distributed optical fiber laid in the same trench as the oil and gas pipeline; obtaining a waterfall plot of optical fiber vibration data based on the vibration excitation signals; obtaining the characteristic connected components of the excitation signals based on the waterfall plot of optical fiber vibration data; determining the space-time series curve and space-velocity series curve of the distributed optical fiber based on the characteristic connected components of the excitation signals; and determining the motion state of the vibration excitation source based on the space-time series curve and space-velocity series curve. This invention enables long-distance passive distributed sensing, has a simple judgment method, and high calculation accuracy. Based on the judgment of the motion state of the vibration source, it can further determine the dwell point of the vibration source, which is beneficial for optimizing the alarm effect of the oil and gas pipeline safety monitoring system and reducing the false alarm rate of the system.

Description

Technical Field

[0001] This invention relates to the field of laser wavelength measurement technology, and specifically to a method, system, and device for analyzing the motion state of an excitation source based on distributed optical fibers. Background Technology

[0002] Distributed fiber optic sensing technology uses communication optical cables laid in the same trench as oil and gas pipelines as vibration sensing and signal transmission elements. It offers advantages such as long-distance operation, real-time performance, corrosion resistance, electromagnetic insufficiency, and portability, and has already been successfully applied in some pipelines. However, the key to improving system performance lies in the analysis and discrimination of vibration signals, effectively alarming against destructive vibrations while reducing the false alarm rate of non-destructive vibrations.

[0003] Under normal operating conditions, the main vibration excitation source frequently detected by fiber optic vibration monitoring systems comes from vehicle vibrations along the pipeline. Normally, vehicle vibrations originating from vehicles traveling on the pipeline are harmless and do not require warning. However, for abnormal activities such as oil theft or drilling, vehicles typically slow down to a stop before the damage begins. Such vehicle vibrations can be detected by the distributed fiber optic vibration monitoring system, necessitating increased alarm sensitivity and warning levels for the corresponding areas to promptly detect and warn of any damage to the oil and gas pipeline.

[0004] Therefore, it is necessary to design a method, system, and device for analyzing the motion state of excitation sources based on distributed optical fibers, in order to improve the detection accuracy of damage behavior in oil and gas pipelines and reduce the false alarm rate of non-destructive vibrations. Summary of the Invention

[0005] In view of this, it is necessary to provide a system and method for analyzing the motion state of excitation sources based on distributed optical fibers, in order to solve the technical problems of high false alarm rate and poor system operation performance when distributed optical fiber sensing technology is used to detect the destructive behavior of oil and gas pipelines.

[0006] To address the aforementioned problems, this invention provides a method for analyzing the motion state of an excitation source based on distributed optical fibers, comprising:

[0007] Acquire vibration excitation signals from all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline;

[0008] A waterfall plot of fiber optic vibration data is obtained based on the vibration excitation signal;

[0009] Based on the fiber vibration data waterfall plot, the characteristic connected components of the excitation signal are obtained;

[0010] The spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber are determined based on the characteristic connected components of the excitation signal.

[0011] The motion state of the vibration excitation source is determined based on the space-time sequence curve and the space-velocity sequence curve.

[0012] Furthermore, obtaining the fiber optic vibration data waterfall plot based on the vibration excitation signal includes:

[0013] Based on the positional order of the detection points on the distributed optical fiber, the vibration excitation signals collected at each moment are spliced ​​together in a spatial-temporal manner to obtain an optical fiber vibration signal matrix within a preset time period.

[0014] A waterfall plot of fiber vibration data is drawn based on the fiber vibration signal matrix.

[0015] Furthermore, based on the fiber vibration data waterfall plot, the characteristic connected components of the excitation signal are obtained, including:

[0016] Calculate the median value of each column of data in the waterfall plot of the fiber optic vibration data, and determine the waterfall plot segmentation threshold based on the median value;

[0017] The fiber vibration data waterfall plot is binarized according to the waterfall plot segmentation threshold to obtain a binarized image;

[0018] The portion of the binarized image whose area exceeds a preset segmentation area threshold is taken as the feature connected region of the excitation signal.

[0019] Furthermore, the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber are determined based on the characteristic connected components of the excitation signal, including:

[0020] Determine the vibration excitation signal time-domain data of all detection points corresponding to the characteristic connected domain of the excitation signal to obtain the connected domain time-domain data;

[0021] Extract the valid data segments with non-zero amplitudes from the connected component time-domain data;

[0022] Based on the time point at which the effective data segment is located in the middle and the corresponding vibration amplitude, the spatial-time series curve of the distributed optical fiber is obtained;

[0023] The space-velocity sequence curve corresponding to the space-time sequence curve is obtained using the sliding window algorithm.

[0024] Furthermore, the space-velocity sequence curve corresponding to the space-time series curve is obtained using a sliding window algorithm, including:

[0025] Spline fitting is performed on the space-time series curve to obtain the corrected curve;

[0026] By sliding a window of a preset length across the correction curve, linear fitting is performed on the data within the window to obtain the space-velocity sequence curve corresponding to the space-time sequence curve.

[0027] Furthermore, determining the motion state of the vibration excitation source based on the space-time series curve and the space-velocity series curve includes:

[0028] Determine whether the changing trends of the space-time series curve and the space-velocity series curve are the same. If the changing trends are the same, determine that the vibration excitation source is accelerating motion; if the changing trends are opposite, determine that the vibration excitation source is decelerating motion.

[0029] Furthermore, the method also includes: determining the dwell point of the vibration excitation source when the motion state of the vibration excitation source is decelerating.

[0030] Furthermore, when the vibration excitation source is in a decelerating motion state, determining the dwell point of the vibration excitation source includes:

[0031] When the motion state of the vibration excitation source is decelerating, the maximum value of the vibration signal of each detection unit is extracted from the fiber vibration data waterfall plot to obtain the maximum value sequence;

[0032] The dwell amplitude threshold is determined based on the described characteristic connected components;

[0033] Determine the first dwell point in the sequence of maximum values ​​that is latest to exceed the dwell amplitude threshold;

[0034] Spline fitting is performed on the maximum value sequence, and peak finding is performed in the spline fitting result to extract the peak position that exceeds the dwell amplitude threshold latest, which is recorded as the second dwell point;

[0035] When the second dwell point exists, the dwell point of the vibration excitation source is the second dwell point; when the second dwell point does not exist, the dwell point of the vibration excitation source is the first dwell point.

[0036] The present invention also provides an excitation source motion state analysis system based on distributed optical fiber, comprising:

[0037] The signal acquisition module is used to acquire the vibration excitation signals of all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline;

[0038] A waterfall plot generation module is used to obtain a waterfall plot of fiber optic vibration data based on the vibration excitation signal.

[0039] The connected component determination module is used to obtain the characteristic connected components of the excitation signal based on the waterfall plot of the fiber vibration data;

[0040] A curve generation module is used to determine the spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber based on the characteristic connected components of the excitation signal.

[0041] The motion state determination module is used to determine the motion state of the vibration excitation source based on the space-time sequence curve and the space-velocity sequence curve.

[0042] The present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the excitation source motion state analysis method based on distributed optical fiber as described in any of the above technical solutions.

[0043] Compared with existing technologies, the beneficial effects of this invention include: First, acquiring the vibration excitation signal of the optical fiber detection point and plotting a waterfall plot of the optical fiber vibration data; second, obtaining the characteristic connected components of the excitation signal based on the optical fiber vibration data waterfall plot; third, determining the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber based on the characteristic connected components; and finally, determining the motion state of the vibration excitation source based on the spatial-time series curve and spatial-velocity series curve. This invention, using distributed optical fiber as the vibration sensing signal detection system, can achieve long-distance passive distributed sensing and has the advantages of high reliability and convenient maintenance. By plotting the vibration signal using a waterfall plot and segmenting the connected components, the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber are obtained. The motion state of the vibration excitation source is determined based on these two curves. The judgment method is simple, the calculation accuracy is high, and it can further determine the residence point of the vibration source based on the judgment of the vibration source's motion state, which is beneficial for optimizing the alarm effect of the oil and gas pipeline safety monitoring system and reducing the false alarm rate of the system. Attached Figure Description

[0044] Figure 1 A flowchart illustrating an embodiment of the excitation source motion state analysis method based on distributed optical fiber provided by the present invention;

[0045] Figure 2 The fiber optic vibration data waterfall provided by this invention Figure 1 A schematic diagram of the embodiment;

[0046] Figure 3 This is a schematic diagram of an embodiment of the binarized image provided by the present invention;

[0047] Figure 4 This is a schematic diagram of an embodiment of the binarized image after connected component extraction provided by the present invention.

[0048] Figure 5 This is a schematic diagram of an embodiment of the space-time series curve provided by the present invention;

[0049] Figure 6 This is a schematic diagram of an embodiment of the correction curve after spline fitting of a space-time series curve provided by the present invention;

[0050] Figure 7 This is a schematic diagram of an embodiment of the space-velocity sequence curve provided by the present invention;

[0051] Figure 8 A schematic diagram of an embodiment of the maximum sequence curve provided by the present invention;

[0052] Figure 9 A schematic diagram of an embodiment of an excitation source motion state analysis system based on distributed optical fiber provided by the present invention;

[0053] Figure 10 This is a schematic diagram of an embodiment of an electronic device provided by the present invention. Detailed Implementation

[0054] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0055] Before describing the embodiments, we will first introduce the application of distributed optical fiber sensing technology in the safety monitoring of oil and gas pipelines.

[0056] Distributed fiber optic sensing technology uses communication optical cables laid in the same trench as oil and gas pipelines as vibration sensing and signal transmission elements. For abnormal activities such as drilling for oil theft, there is usually a vehicle decelerating to a stop before the act of damaging the pipeline begins. Therefore, it is necessary to improve the alarm sensitivity and early warning level of such signals to provide timely warnings of pipeline damage. Thus, rapid and accurate judgment of the motion state of vibration signal sources is of great significance for the safety monitoring of oil and gas pipelines.

[0057] This invention provides a method for analyzing the motion state of excitation sources based on distributed optical fibers, such as... Figure 1 As shown, Figure 1 This is a flowchart illustrating the motion state analysis method for excitation sources based on distributed optical fibers, including:

[0058] Step S101: Obtain the vibration excitation signals of all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline;

[0059] Step S102: Obtain a waterfall plot of fiber optic vibration data based on the vibration excitation signal;

[0060] Step S103: Obtain the characteristic connected components of the excitation signal based on the waterfall plot of the fiber vibration data;

[0061] Step S104: Determine the spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber based on the characteristic connected components of the excitation signal;

[0062] Step S105: Determine the motion state of the vibration excitation source based on the space-time sequence curve and the space-velocity sequence curve.

[0063] This embodiment provides a method for analyzing the motion state of an excitation source based on distributed optical fiber. First, the vibration excitation signal from the optical fiber detection point is acquired, and a waterfall plot of the optical fiber vibration data is drawn. Second, the characteristic connected components of the excitation signal are obtained based on the waterfall plot. Third, the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber are determined based on the characteristic connected components. Finally, the motion state of the vibration excitation source is determined based on the spatial-time series curve and spatial-velocity series curve. This embodiment uses distributed optical fiber as the detection system for the vibration sensing signal of the excitation source, enabling long-distance passive distributed sensing with advantages such as high reliability and convenient maintenance. By drawing a waterfall plot and segmenting the connected components of the vibration signal, the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber are obtained. The motion state of the vibration excitation source is determined based on these two curves. The judgment method is simple, the calculation accuracy is high, and it can further determine the residence point of the vibration source based on the judgment of the motion state, which is beneficial to optimizing the alarm effect of the oil and gas pipeline safety monitoring system and reducing the false alarm rate of the system.

[0064] In a preferred embodiment, step S102, obtaining the fiber optic vibration data waterfall plot based on the vibration excitation signal, includes:

[0065] Based on the positional order of the detection points on the distributed optical fiber, the vibration excitation signals collected at each moment are spliced ​​together in a spatial-temporal manner to obtain an optical fiber vibration signal matrix within a preset time period.

[0066] A waterfall plot of fiber vibration data is drawn based on the fiber vibration signal matrix.

[0067] In a preferred embodiment, in step S103, the characteristic connected components of the excitation signal are obtained based on the fiber vibration data waterfall plot, including:

[0068] Calculate the median value of each column of data in the waterfall plot of the fiber optic vibration data, and determine the waterfall plot segmentation threshold based on the median value;

[0069] The fiber vibration data waterfall plot is binarized according to the waterfall plot segmentation threshold to obtain a binarized image;

[0070] The portion of the binarized image whose area exceeds a preset segmentation area threshold is taken as the feature connected region of the excitation signal.

[0071] In a preferred embodiment, step S104, determining the space-time series curve and space-velocity series curve of the distributed optical fiber based on the characteristic connected components of the excitation signal, includes:

[0072] Determine the vibration excitation signal time-domain data of all detection points corresponding to the characteristic connected domain of the excitation signal to obtain the connected domain time-domain data;

[0073] Extract the valid data segments with non-zero amplitudes from the connected component time-domain data;

[0074] Based on the time point at which the effective data segment is located in the middle and the corresponding vibration amplitude, the spatial-time series curve of the distributed optical fiber is obtained;

[0075] The space-velocity sequence curve corresponding to the space-time sequence curve is obtained using the sliding window algorithm.

[0076] In a preferred embodiment, the space-velocity sequence curve corresponding to the space-time sequence curve is obtained using a sliding window algorithm, including:

[0077] Spline fitting is performed on the space-time series curve to obtain the corrected curve;

[0078] By sliding a window of a preset length across the correction curve, linear fitting is performed on the data within the window to obtain the space-velocity sequence curve corresponding to the space-time sequence curve.

[0079] In a preferred embodiment, step S105, determining the motion state of the vibration excitation source based on the space-time sequence curve and the space-velocity sequence curve, includes:

[0080] Determine whether the changing trends of the space-time series curve and the space-velocity series curve are the same. If the changing trends are the same, determine that the vibration excitation source is accelerating motion; if the changing trends are opposite, determine that the vibration excitation source is decelerating motion.

[0081] The following combination Figures 2 to 7 The motion state process of the above-mentioned vibration excitation source is described in detail.

[0082] Step 1: Connect the communication optical cable laid in the same trench as the oil and gas pipeline to the distributed fiber optic vibration measurement system. This cable will act as a vibration sensor to collect vibration excitation signals along the pipeline. Based on the location sequence of the monitoring units, the data collected at various times are spliced ​​spatially and temporally to obtain a full-segment vibration signal matrix over a given period. A fiber optic vibration data waterfall plot is then created based on this matrix, with each column representing the time-domain signal of each detection point. The fiber optic vibration data waterfall plot is shown below. Figure 2 As shown.

[0083] The second step is to first calculate the median of each column of the waterfall plot, that is, to extract the median of the signal amplitude of the time series at each detection point to obtain the time-series median sequence; then calculate the median of the time-series median sequence to obtain the spatial sequence median, and multiply the spatial sequence median by a preset multiple n using the spatial sequence median as the base value. a (For example, a value of 10 can be used, and the range of values ​​can be adjusted according to the actual situation), thus obtaining the waterfall plot segmentation threshold. This segmentation threshold is then used to binarize the waterfall plot; for example... Figure 3 As shown, Figure 3 This is the binarized image after segmenting the waterfall plot.

[0084] Step 3: Perform connected component extraction on the binarized image, finding connected components whose area exceeds a preset segmentation area threshold of S pixels, thus obtaining the feature connected components of the excitation signal; where S is adjusted according to the actual situation. Figure 4 As shown, Figure 4 The binarized image after connected component extraction is shown.

[0085] Step 4: For the characteristic connected domain of the excitation signal, extract the effective data segments with non-zero amplitudes within the characteristic connected domain range of the original time-domain signal at each detection point, and find the time point located in the middle position, thereby obtaining the spatial-time series curve of the distributed optical fiber. For example... Figure 5 As shown, Figure 5 This is a schematic diagram of a space-time series curve.

[0086] Step 5: Perform smooth spline fitting on the space-time series curve to correct for discontinuities in the time-point positioning curve; for example... Figure 6 As shown, Figure 6 This is a schematic diagram of the corrected curve after spline fitting of the space-time series curve.

[0087] Step 6: Using a window of length L, slide it across the space-time series, perform linear fitting on the data within the window, and correlate the fitting coefficients with the center of the window to obtain the space-velocity series curve; the sliding window length L is greater than 3 detection points but less than the total detection length, typically taken as 50. Figure 7 As shown, Figure 7 This is a schematic diagram of the space-velocity sequence curve.

[0088] Step 7: Based on the spatial-temporal correspondence (i.e., spatial-time series curve) and speed change trend (i.e., spatial-speed series curve), acceleration and deceleration signals can be distinguished: for acceleration, the trends of these two correspondences are the same, while for deceleration, the trends are opposite. For abnormal behaviors such as puncturing for oil theft, there is usually a vehicle deceleration to a complete stop before the act of damaging the pipeline begins. Therefore, deceleration and stopping should be the focus of detection, and alarm sensitivity and warning levels should be increased.

[0089] In order to locate the dwell position of the vibration excitation source, as a preferred embodiment, the method further includes: determining the dwell point of the vibration excitation source when the motion state of the vibration excitation source is decelerating.

[0090] In a preferred embodiment, when the motion state of the vibration excitation source is decelerating, determining the dwell point of the vibration excitation source includes:

[0091] When the motion state of the vibration excitation source is decelerating, the maximum value of the vibration signal of each detection unit is extracted from the fiber vibration data waterfall plot to obtain the maximum value sequence;

[0092] The dwell amplitude threshold is determined based on the described characteristic connected components;

[0093] Determine the first dwell point in the sequence of maximum values ​​that is latest to exceed the dwell amplitude threshold;

[0094] Spline fitting is performed on the maximum value sequence, and peak finding is performed in the spline fitting result to extract the peak position that exceeds the dwell amplitude threshold latest, which is recorded as the second dwell point;

[0095] When the second dwell point exists, the dwell point of the vibration excitation source is the second dwell point; when the second dwell point does not exist, the dwell point of the vibration excitation source is the first dwell point.

[0096] The following combination Figure 8 The process of determining the residence point of the incentive source is explained in detail.

[0097] Step 1: For the excitation data segment identified as a deceleration signal, find the maximum value of the sampled data from each detection unit in the fiber optic vibration data waterfall plot to obtain the maximum value sequence; for example... Figure 8 As shown, Figure 8 A schematic diagram of the curve for the maximum sequence;

[0098] Step 2: For the maximum value sequence, determine the stopping interval based on the spatial region where the connected components are located, and extract the data segment after the stopping (for calculating the noise floor). Determine the median of the data segment, multiply it by a preset multiple, and use it as the dwell amplitude threshold. Find the position in the maximum value sequence that is latest to exceed this threshold, and denote it as the first dwell point P. a ;like Figure 8 As shown, Figure 8 The circle in the diagram indicates the position Pa;

[0099] Step 3: Perform a smooth spline fit on the maximum value sequence; Figure 8 In the diagram, the thick black line represents the result after spline fitting. Peaks are found in the smooth spline fitting results, and the position of the latest peak is extracted and denoted as the second residence point P. b ( Figure 8 The asterisks in the diagram indicate the positions (in this figure, Pa and Pb coincide); if P b If it exists, then the residence point of the stimulus source = P b If P b If it does not exist, then the stimulus source residence point = P a .

[0100] Since extracting the left / right boundaries of the connected components of the image to locate the dwell position of the excitation source is not the most accurate method for the excitation patch obtained by threshold segmentation of the waterfall image, the signal amplitude of the vehicle excitation source will undergo a jump during the short time of braking. Therefore, in the third step, the dwell position of the excitation source can be located more accurately by finding the position of the last peak point of the signal amplitude.

[0101] This embodiment also provides a motion state analysis system for excitation sources based on distributed optical fibers, such as... Figure 9 As shown, the excitation source motion state analysis system 900 based on distributed optical fiber includes:

[0102] The signal acquisition module 901 is used to acquire the vibration excitation signals of all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline.

[0103] The waterfall plot generation module 902 is used to obtain a waterfall plot of fiber optic vibration data based on the vibration excitation signal.

[0104] The connected component determination module 903 is used to obtain the characteristic connected components of the excitation signal based on the fiber vibration data waterfall plot.

[0105] Curve generation module 904 is used to determine the spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber based on the characteristic connected components of the excitation signal.

[0106] The motion state determination module 905 is used to determine the motion state of the vibration excitation source based on the space-time sequence curve and the space-velocity sequence curve.

[0107] like Figure 10 As shown in the above-described method for analyzing the motion state of an excitation source based on distributed optical fiber, this invention also provides an electronic device 1000, which can be a mobile terminal, desktop computer, laptop, handheld computer, server, or other computing device. The electronic device includes a processor 1001, a memory 1002, and a display 1003.

[0108] In some embodiments, memory 1002 may be an internal storage unit of a computer device, such as a hard disk or memory. In other embodiments, memory 1002 may be an external storage device of a computer device, such as a plug-in hard disk, smart media card (SMC), secure digital card (SD), flash card, etc., provided on the computer device. Further, memory 1002 may include both internal and external storage units of the computer device. Memory 1002 is used to store application software and various types of data installed on the computer device, such as program code for installing the computer device. Memory 1002 can also be used to temporarily store data that has been output or will be output. In one embodiment, memory 1002 stores a program 1004 for a distributed optical fiber-based excitation source motion state analysis method, which can be executed by processor 1001 to implement a distributed optical fiber-based excitation source motion state analysis method according to various embodiments of the present invention.

[0109] In some embodiments, processor 1001 may be a central processing unit (CPU), microprocessor or other data processing chip, used to run program code stored in memory 1002 or process data, such as executing a motion state analysis program for an excitation source based on distributed optical fiber.

[0110] In some embodiments, display 1003 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 1003 is used to display information on the computer device and to display a visual user interface. Components 1001-1003 of the computer device communicate with each other via a system bus.

[0111] The present invention discloses a method, system, and device for analyzing the motion state of an excitation source based on distributed optical fiber. First, the vibration excitation signal of the optical fiber detection point is acquired and a waterfall plot of the optical fiber vibration data is plotted. Second, the characteristic connected components of the excitation signal are obtained based on the optical fiber vibration data waterfall plot. Third, the space-time series curve and space-velocity series curve of the distributed optical fiber are determined based on the characteristic connected components. Finally, the motion state of the vibration excitation source is determined based on the space-time series curve and space-velocity series curve.

[0112] This invention relates to a vibration sensing signal detection system using distributed optical fiber as the excitation source. It enables long-distance passive distributed sensing and offers advantages such as high reliability and ease of maintenance. By plotting the vibration signal using a waterfall diagram and segmenting connected components, the spatial-time and spatial-velocity sequence curves of the distributed optical fiber are obtained. The motion state of the vibration excitation source is determined based on these two curves. The method is simple, the calculation accuracy is high, and it can further determine the residence point of the vibration source based on the determined motion state. This is beneficial for optimizing the alarm effect of the oil and gas pipeline safety monitoring system and reducing the false alarm rate.

[0113] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for analyzing the motion state of an excitation source based on distributed optical fiber, characterized in that, include; Acquire vibration excitation signals from all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline; A waterfall plot of fiber optic vibration data is obtained based on the vibration excitation signal; Based on the fiber vibration data waterfall plot, the characteristic connected components of the excitation signal are obtained; The spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber are determined based on the characteristic connected components of the excitation signal. The motion state of the vibration excitation source is determined based on the space-time sequence curve and the space-velocity sequence curve. Based on the fiber vibration data waterfall plot, the characteristic connected components of the excitation signal are obtained, including: Calculate the median value of each column of data in the waterfall plot of the fiber optic vibration data, and determine the waterfall plot segmentation threshold based on the median value; The fiber vibration data waterfall plot is binarized according to the waterfall plot segmentation threshold to obtain a binarized image; The portion of the binarized image whose area exceeds a preset segmentation area threshold is taken as the feature connected region of the excitation signal. When the motion state of the vibration excitation source is decelerating, determine the dwell point of the vibration excitation source; When the motion state of the vibration excitation source is decelerating, the maximum value of the vibration signal of each detection unit is extracted from the fiber vibration data waterfall plot to obtain the maximum value sequence; The dwell amplitude threshold is determined based on the described characteristic connected components; Determine the first dwell point in the sequence of maximum values ​​that is latest to exceed the dwell amplitude threshold; Spline fitting is performed on the maximum value sequence, and peak finding is performed in the spline fitting result to extract the peak position that exceeds the dwell amplitude threshold latest, which is recorded as the second dwell point; When the second dwell point exists, the dwell point of the vibration excitation source is the second dwell point; when the second dwell point does not exist, the dwell point of the vibration excitation source is the first dwell point.

2. The method for analyzing the motion state of an excitation source based on distributed optical fiber according to claim 1, characterized in that, The fiber optic vibration data waterfall plot is obtained based on the vibration excitation signal, including: Based on the spatial location of the detection points on the distributed optical fiber, the vibration excitation signals collected at each moment are spliced ​​together in a space-time manner to obtain the optical fiber vibration signal matrix within a preset time period. A waterfall plot of fiber vibration data is drawn based on the fiber vibration signal matrix.

3. The method for analyzing the motion state of an excitation source based on distributed optical fiber according to claim 1, characterized in that, Determining the spatial-time series curve and spatial-velocity series curve of the distributed optical fiber based on the characteristic connected components of the excitation signal includes: Determine the vibration excitation signal time-domain data of all detection points corresponding to the characteristic connected domain of the excitation signal to obtain the connected domain time-domain data; Extract the valid data segments with non-zero amplitudes from the connected component time-domain data; Based on the time point at which the effective data segment is located in the middle and the corresponding vibration amplitude, the spatial-time series curve of the distributed optical fiber is obtained; The space-velocity sequence curve corresponding to the space-time sequence curve is obtained using the sliding window algorithm.

4. The method for analyzing the motion state of an excitation source based on distributed optical fiber according to claim 3, characterized in that, The space-velocity sequence curve corresponding to the space-time series curve is obtained using the sliding window algorithm, including: Spline fitting is performed on the space-time series curve to obtain the corrected curve; By sliding a window of a preset length across the correction curve, linear fitting is performed on the data within the window to obtain the space-velocity sequence curve corresponding to the space-time sequence curve.

5. The method for analyzing the motion state of an excitation source based on distributed optical fiber according to claim 1, characterized in that, Determining the motion state of the vibration excitation source based on the space-time series curve and the space-velocity series curve includes: Determine whether the changing trends of the space-time series curve and the space-velocity series curve are the same. If the changing trends are the same, determine that the vibration excitation source is accelerating motion; if the changing trends are opposite, determine that the vibration excitation source is decelerating motion.

6. A motion state analysis system for excitation sources based on distributed optical fibers, characterized in that, include: The signal acquisition module is used to acquire the vibration excitation signals of all detection points on the distributed optical fiber laid in the same trench as the oil and gas pipeline; A waterfall plot generation module is used to obtain a waterfall plot of fiber optic vibration data based on the vibration excitation signal. The connected component determination module is used to obtain the characteristic connected components of the excitation signal based on the waterfall plot of the fiber vibration data; A curve generation module is used to determine the spatial-time sequence curve and spatial-velocity sequence curve of the distributed optical fiber based on the characteristic connected components of the excitation signal. The motion state determination module is used to determine the motion state of the vibration excitation source based on the space-time sequence curve and the space-velocity sequence curve. Based on the fiber vibration data waterfall plot, the characteristic connected components of the excitation signal are obtained, including: Calculate the median value of each column of data in the waterfall plot of the fiber optic vibration data, and determine the waterfall plot segmentation threshold based on the median value; The fiber vibration data waterfall plot is binarized according to the waterfall plot segmentation threshold to obtain a binarized image; The portion of the binarized image whose area exceeds a preset segmentation area threshold is taken as the feature connected region of the excitation signal. When the motion state of the vibration excitation source is decelerating, determine the dwell point of the vibration excitation source; When the motion state of the vibration excitation source is decelerating, the maximum value of the vibration signal of each detection unit is extracted from the fiber vibration data waterfall plot to obtain the maximum value sequence; The dwell amplitude threshold is determined based on the described characteristic connected components; Determine the first dwell point in the sequence of maximum values ​​that is latest to exceed the dwell amplitude threshold; Spline fitting is performed on the maximum value sequence, and peak finding is performed in the spline fitting result to extract the peak position that exceeds the dwell amplitude threshold latest, which is recorded as the second dwell point; When the second dwell point exists, the dwell point of the vibration excitation source is the second dwell point; when the second dwell point does not exist, the dwell point of the vibration excitation source is the first dwell point.

7. An electronic device, characterized in that, It includes a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the excitation source motion state analysis method based on any one of claims 1-5.

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