Submarine cable electrical defect fault position detection system and method

Abstract

The invention relates to the technical field of submarine cable fault detection, in particular to a submarine cable electrical defect fault position detection system and method, and the method comprises the steps: carrying out the data sampling of a submarine cable, and obtaining original signal data; performing data preprocessing on the original data to obtain processed signal data, and performing decomposition of different scales on the processed signal by using wavelet transform; searching a local maximum point of the wavelet transform coefficient on a time axis to obtain a modulus maximum point, and determining a propagation time difference; determining the position of a fault point according to the distance measurement equation; and performing preliminary correction on the initial position based on the abnormal performance of the water flow impact, determining a preliminary correction fault point, performing information extraction on the sediment sample in the sampling range, and determining a final correction fault point. According to the invention, fault point correction is carried out by using submarine cable peripheral water flow impact abnormity and submarine sediment change, dependence on a complex electrical detection technology and professional equipment is eliminated, and the problems of high cost, complex operation, need of professional technicians and the like in the prior art are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of submarine cable fault detection, in particular to a detection system and method for the position of an electrical defect fault of a submarine cable. BACKGROUND

[0002] As a core carrier for cross-sea power transmission and communication, a submarine cable is long-term operated in a high-humidity, high-voltage and strong-corrosion submarine environment, and is prone to electrical defect faults such as short circuit and open circuit due to insulation aging and mechanical damage. Accurate detection of the fault position is crucial for rapid repair and system stability. Existing technologies mostly rely on electrical detection methods such as traveling wave distance measurement and pulse reflection, which require high-precision acquisition equipment, professional algorithms and complex data processing procedures, and have problems such as high cost, high operation threshold and strong dependence on technical personnel, especially in scenarios lacking advanced detection facilities. In addition, the traditional method is prone to signal interference in the complex and variable submarine environment, and the positioning accuracy is limited.

[0003] Therefore, there is an urgent need for a low-cost, easy-to-operate and complex-environment-adaptive submarine cable fault position detection scheme to make up for the shortcomings of existing technologies and improve fault detection efficiency and reliability. SUMMARY

[0004] The purpose of the present application is to overcome the shortcomings of the prior art and provide a detection system and method for the position of an electrical defect fault of a submarine cable to solve the problems in the prior art that the traditional method is prone to signal interference in the complex and variable submarine environment, the positioning accuracy is limited, and the submarine electrical defect fault is difficult to detect accurately.

[0005] To achieve the above purpose, the following technical solutions are adopted: A detection method for the position of an electrical defect fault of a submarine cable, comprising the following steps: S1, collecting a traveling wave signal of the submarine cable to obtain original signal data; S2, performing data preprocessing on the original signal data to obtain processed signal data, and decomposing the processed signal data into a low-frequency approximation part and a high-frequency detail part through wavelet transform to obtain corresponding wavelet transform coefficients; S3, obtaining a local maximum point on a time axis from the wavelet transform coefficients, obtaining a modulus maximum point based on the local maximum point, and determining a propagation time difference through the modulus maximum point; S4, determining an initial position of the fault point through a distance measurement equation based on the propagation time difference; S5, preliminarily correcting the initial position based on the abnormal performance of water flow impact to preliminarily correct the position of the fault point; S6, collecting a sediment sample, and obtaining a final corrected fault point position from the preliminarily corrected fault point based on the submarine cable breaking characteristics in the collected sediment sample.

[0006] The further improvement of the present application is that: Preferably, in S1, the traveling wave signal of the submarine cable is collected by the traveling wave collection device.

[0007] Preferably, in S2, the data preprocessing is a noise reduction processing on the original signal data to obtain the processed signal data.

[0008] Preferably, in S3, the process of determining the propagation time difference by the modulus maximum point is that: selecting the time corresponding to the modulus maximum point with the earliest time, taking the time as the initial wave head of the signal, and determining the time of the wave head from one end of the submarine cable to the other end as the propagation time difference.

[0009] Preferably, in S4, the initial position of the fault point is determined by determining the distance from the fault point to one end. The distance from the fault point to one end is calculated by the formula: (2) In the formula, is the output time of the processed signal at the A end; is the receiving time of the processed signal at the B end; and x is the distance from the fault point to the A end.

[0010] Preferably, the specific process of S5 is: S51, placing a sub-region at a standard distance on the submarine cable laying path, collecting buoy data in each sub-region; the buoy data includes the water flow direction, flow speed, and marker band position offset; S52, calculating the parameter difference of the water flow direction, flow speed, and marker band position offset by the formula parameter difference calculation formula, to obtain the water flow angle difference, flow speed difference, and marker band position offset difference; S53, comparing the water flow angle difference with the preset angle difference threshold, the flow speed difference with the flow speed difference threshold, and the marker band position offset difference with the marker band position offset difference threshold; if any parameter difference is greater than the corresponding difference threshold, it is determined that the buoy has abnormal water flow, and S54 is executed; otherwise, the initial position of the existing fault point is taken as the preliminary corrected fault point position; S54, if more than a set threshold number of buoys in the same sub-region have abnormal water flow determination results, the sub-region is determined as the fault point range after preliminary correction, and the center position of the fault point range is taken as the preliminary corrected fault point.

[0011] Preferably, in S54, if multiple adjacent sub-regions have abnormal water flow determination results, the multiple sub-regions are merged as the fault point range, and the center position of the fault point range is taken as the preliminary corrected fault point.

[0012] Preferably, the specific process of S6 is: S61, determining a sampling range with the preliminary corrected fault point position as the center, sampling the sediment in the sampling range, and obtaining a sediment sample; S62, judging whether the sediment sample has a submarine cable breaking feature, and obtaining a final corrected fault point position.

[0013] Preferably, in S62, the judging whether the sediment sample has a submarine cable breaking feature and obtaining a final corrected fault point position includes the following three cases: Case one: if the sediment sample has a submarine cable breaking feature, the sample collection point of the sediment sample is the final corrected fault point position; Case two: if there are multiple sediment samples having a submarine cable breaking feature, the geometric center point of the positions of the multiple sample collection points is taken as the final corrected fault point position; Case three: if there is no sediment sample having a submarine cable breaking feature, the preliminary corrected fault point position is the final corrected fault point.

[0014] A detection system of a submarine cable electrical defect fault position, comprising: A data acquisition unit is configured to collect a traveling wave signal of a submarine cable and obtain original signal data. A data decomposition unit is configured to perform data preprocessing on the original signal data to obtain processed signal data, and decompose the processed signal data into a low-frequency approximation part and a high-frequency detail part through wavelet transform to obtain corresponding wavelet transform coefficients. A time difference determination unit is configured to obtain a local maximum value point on a time axis from the wavelet transform coefficients, obtain a modulus maximum value point based on the local maximum value point, and determine a propagation time difference through the modulus maximum value point. An initial fault unit is configured to determine an initial position of a fault point through a ranging equation based on the propagation time difference. A preliminary correction unit is configured to preliminarily correct the initial position based on water flow impact abnormality, and preliminarily correct a fault point position. A final correction unit is configured to collect a sediment sample, and obtain a final corrected fault point position from the preliminarily corrected fault point based on a submarine cable breaking feature in the collected sediment sample.

[0015] Compared with the prior art, the present application has the following beneficial effects: The application discloses a kind of detection methods of submarine cable electrical defect fault position, by collecting travelling wave signal and decomposition processing, module maximum point determines propagation time difference, in combination with water flow impact correction and sediment sample verification, obtain the final fault location, the present application utilizes submarine cable peripheral water flow impact anomaly and submarine sediment variation to carry out fault point correction, get rid of the dependence on complex electrical detection technology and professional equipment, solve the problems, such as high cost of prior art, complex operation, need professional technical personnel etc., the method comprehensively improves fault location precision, with the advantages of improving fault location precision, reducing environmental interference, reducing detection cost and operation difficulty. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 For the flow chart of the submarine cable electrical defect fault position detection method of the application; Figure 2 For the flow chart of the method of preliminary correction fault point of the application; Figure 3 For the flow chart of the method of determining final correction fault point of the application. DETAILED DESCRIPTION

[0017] Hereinafter, the terms "first", "second", "third", "fourth" are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second", "third", "fourth" can explicitly or implicitly include one or more of the features.

[0018] The method of shooting provided by the embodiments of the present application can be applied to terminal devices such as mobile phones, tablet computers, wearable devices, vehicle-mounted devices, augmented reality (AR) / virtual reality (VR) devices, notebook computers, ultra-mobile personal computers (UMPC), netbooks, personal digital assistants (PDA), etc. The embodiments of the present application do not make any limitation on the specific type of terminal device.

[0019] It should be noted that the terms "first", "second", and the like in the description and in the claims of the present application are used for distinguishing between similar objects and not necessarily for describing a specific sequential or chronological order. It is to be understood that the use of such terms herein is only to facilitate identifying the description of the embodiments of the application and that the terms are not necessarily a limitation on the scope of the application. Moreover, the terms "comprise", "comprising", and "comprises", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is, meanings and scope of term should be given the broadest interpretation so as to encompass the entire process, method, system, product, or apparatus that the terms directly or indirectly refer to. Additionally, it should be understood that although the terms "first", "second" etc. can be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another. It will be understood that like terms and phrases including related terms and phrases can be readily inferred from the description.

[0020] Referring to Figure 1 The first aspect of the present application discloses a method for detecting the location of an electrical defect fault of a submarine cable, comprising the following steps: S1, collecting a traveling wave signal of the submarine cable to obtain original signal data; S2, performing data preprocessing on the original signal data to obtain processed signal data, and decomposing the processed signal data into a low-frequency approximation part and a high-frequency detail part through wavelet transform to obtain corresponding wavelet transform coefficients; S3, obtaining a local maximum point on a time axis from the wavelet transform coefficients, obtaining a modulus maximum point based on the local maximum point, and determining a propagation time difference through the modulus maximum point; S4, determining an initial position of the fault point through a ranging equation based on the propagation time difference; S5, preliminarily correcting the initial position based on abnormal performance of water flow impact, and correcting the position of the fault point; S6, collecting a sediment sample, and obtaining a final corrected fault point position from the preliminarily corrected fault point based on a submarine cable breaking feature in the collected sediment sample.

[0021] After the traveling wave signal is obtained by the collecting device, the submarine environmental noise is removed through noise reduction processing. The processed signal is decomposed into low-frequency and high-frequency components, the modulus maximum point is extracted to obtain the arrival time difference of the traveling wave, and the initial fault position is calculated by combining the ranging equation. Then, the buoy data in the water flow abnormal area is compared, and if the parameter exceeds the threshold value, the fault range is adjusted. Finally, the sediment sample is collected in the correction area, and the final fault point is verified and determined by detecting the breaking feature. For example, in the preliminary correction stage, if the water flow is abnormal in the adjacent sub-regions, the center of the combined region is taken as the new positioning point; in the final correction stage, the geometric center of multiple sampling points containing the breaking feature can improve the positioning accuracy.

[0022] Compared with the prior art, the traditional method only relies on electrical signal analysis and does not consider the interference of the seabed environment on positioning. The scheme effectively offsets the signal propagation error caused by the flow impact by introducing a double correction mechanism of flow monitoring and sediment verification, solving the problem that single electrical detection is easily disturbed by the environment. At the same time, wavelet transform decomposition is used instead of a complex pulse reflection algorithm, reducing the demand for high-precision equipment and making the detection process more suitable for operation scenarios lacking advanced facilities.

[0023] In some embodiments of the present application, in S1, high-precision traveling wave acquisition devices are installed at both ends of the submarine cable respectively to sample data of the submarine cable and obtain original signal data.

[0024] Among them, the traveling wave acquisition device refers to a special device for capturing transient current or voltage changes in the submarine cable conductor, which can be implemented by a piezoelectric sensor or an electromagnetic induction unit. It is coupled to the surface of the submarine cable through physical contact or non-contact mode, and converts the traveling wave signal inside the conductor into a measurable electrical signal.

[0025] Among them, the traveling wave signal refers to the electromagnetic transient wave propagating in the submarine cable conductor when a fault occurs, which is specifically manifested as a sudden change in voltage or current. Its propagation speed is related to the conductor material and the dielectric constant of the insulating layer. By detecting the signal, the position information of the fault occurrence can be reflected.

[0026] In some embodiments of the present application, in S2, the preprocessing is to perform noise reduction processing on the original signal. The noise reduction processing refers to eliminating the interference components in the original signal through signal processing technology. Specifically, it can be implemented by using the wavelet threshold denoising method to suppress high-frequency noise components and retain effective signal components. The processed signal data refers to the signal data after noise reduction, and the signal-to-noise ratio is improved to provide basic data quality assurance for subsequent wavelet transform decomposition and avoid noise interference leading to false judgment of the modulus maximum point.

[0027] Specifically, the original signal data may be affected by factors such as seabed environmental noise and electromagnetic interference during the acquisition process, resulting in signal waveform distortion. Through the wavelet threshold denoising method, the original signal is first decomposed at multiple scales to separate high-frequency detail components of different frequency bands. The threshold value is applied to each high-frequency component to eliminate random noise, and the signal is finally reconstructed to obtain the processed signal data. For example, in the decomposition process, db4 wavelet basis function can be used for 5-layer decomposition, and soft threshold value processing is used for the 1st-3rd layer high-frequency coefficients, so as to effectively remove high-frequency noise without damaging the signal mutation characteristics.

[0028] In some embodiments of the present application, in S2, the formula of wavelet transform is: (1) In the formula, a and b are the wavelet transform parameters, and c is the wavelet transform coefficient. is a wavelet basis function; a is a scale parameter, and b is a translation parameter. is a wavelet basis function; a is a scale parameter, and b is a translation parameter.

[0029] The processing signal is divided into a low-frequency approximation part and a high-frequency detail part, and the corresponding coefficients are respectively referred to as low-frequency approximation coefficients and high-frequency detail coefficients. In S3, local maximum points of wavelet transform coefficients on the time axis are searched in the low-frequency approximation coefficients and the high-frequency detail coefficients.

[0030] It should be understood that the modulus maximum point refers to a point at which the modulus (absolute value) of the wavelet transform coefficient reaches a local maximum in the neighborhood of the point at a certain scale. Therefore, in some embodiments of the present application, the modulus maximum point is obtained based on the local maximum point by a directional derivative method, a neighborhood comparison method, or a Lipschitz index method in S3.

[0031] In some embodiments of the present application, a method for determining the propagation time difference based on the modulus maximum point in S3 is as follows: The time corresponding to the modulus maximum point with the earliest time is selected as the time at which the signal initial wave front reaches the other end from one end of the submarine cable, and is marked as the propagation time difference .

[0032] Further, the length L of the submarine cable is obtained, and the signal propagation speed v is calculated by the formula . In some embodiments of the present application, a ranging equation is determined by using a double-end traveling wave ranging principle in S4, and the position of the fault point is determined according to the ranging equation. The ranging equation is as follows: (2) In the formula, is the output time of the processing signal at the A end; is the receiving time of the processing signal at the B end; and x is the distance from the fault point to the A end. According to the distance from the fault point to the A end, the initial position of the fault point is determined. The traditional method relies on complex algorithms such as wavelet transform for signal feature extraction, and requires the configuration of a high-performance computing unit. However, the present scheme avoids the multi-layer signal decomposition and reconstruction process by establishing a direct physical mathematical model to convert the time parameter into a spatial coordinate, thereby reducing the data processing complexity. At the same time, since a two-end time synchronous acquisition mechanism is adopted, the error accumulation caused by the environmental interference of a single sensor signal is effectively reduced.

[0033] Referring to Figure 2 In some embodiments of the present application, the initial position is preliminarily corrected based on the abnormal performance of water flow impact in S5, and a preliminarily corrected fault point is determined On the cable laying path, a sub-area is set every standard distance, a buoy device is placed in each sub-area, an elongated flexible rod is connected to the bottom of each buoy device, the bottom end of the flexible rod is fixed to the seabed directly above the submarine cable, a simple flow direction and flow rate monitoring device is installed on the buoy, which is used to record the flow direction and flow rate data in real time.

[0034] Based on the above-mentioned submarine cable laying buoy device, the method for determining the preliminary corrected fault point comprises the following steps: S51, collecting buoy data. Based on the initial position of the fault point, the operation and maintenance personnel are notified to go to the area and the surrounding area to check the flow monitoring data of the buoy device and the marker belt state, and obtain the buoy data, including the flow direction, flow rate, and marker belt position offset.

[0035] S52, data processing and analysis of buoy data, including converting the flow direction into a flow angle, and then calculating the parameter difference value of each buoy data, specifically calculating the difference value of the flow angle, flow rate, and marker belt position offset; the specific calculation method of each parameter is: For each sub-area, the parameter difference value is calculated by the formula The parameter difference value is calculated as ; in the formula, is the i-th buoy parameter, i is the buoy number, and i is a positive integer; is the average value of the buoy parameters in the sub-area.

[0036] S53, the flow angle difference value, flow rate difference value, and marker belt position offset difference value of the buoy are calculated based on the parameter difference value calculation formula, and the flow angle difference value, flow rate difference value, and marker belt position offset difference value are compared with the preset angle difference value threshold, flow rate difference value threshold, and marker belt position offset difference value threshold, respectively. If any parameter difference value is greater than the corresponding difference value threshold, it is determined that the buoy has abnormal flow.

[0037] S54, determining the fault point range, including the following two cases: Case one: if more than half of the buoys in the same sub-area have abnormal flow determination results, the sub-area is determined as the preliminary corrected fault point range; If multiple adjacent sub-areas have abnormal flow determination results, these sub-areas are combined as the fault point range.

[0038] The center position of the fault point range is taken as the preliminary corrected fault point.

[0039] Case two: if there is no parameter difference value greater than the corresponding difference value threshold, the existing fault point marker is taken as the preliminary corrected fault point.

[0040] Specifically, when multiple adjacent sub-regions trigger the abnormal water flow determination, it indicates that there is a large-scale water flow impact anomaly in the region, at this time the adjacent sub-regions are merged into a unified fault range, and the geometric center point of the merged region is calculated to determine the preliminary correction position. For example, if three consecutive sub-regions (for example, A3, A4, A5 regions with a distance of 500 meters) all have a flow rate difference of more than 70% of the buoys above the threshold value, then the three regions are merged into a rectangular region, and the geometric center point coordinates are calculated as the preliminary correction point. This way can avoid misjudgment caused by local water flow mutation, and at the same time reduce the influence of single sub-region boundary error on positioning.

[0041] Compared with the prior art, the traditional method relies on single electrical signal analysis and does not consider the influence of submarine water flow impact on fault location, which is easy to cause positioning deviation due to environmental interference. The method can dynamically identify the submarine cable displacement or damage area caused by water flow impact and effectively distinguish electrical signal anomalies and environmental interference factors by introducing a buoy network monitoring and multi-parameter threshold determination mechanism.

[0042] Referring to Figure 3 In some embodiments of the present application, in S6, information extraction is performed on the sediment samples in the sampling range to determine the final corrected fault point. The method comprises: S61, setting a sampling range composed of a sampling radius based on the preliminary corrected fault point, deploying multiple submarine sediment sampling devices within the sampling range for sediment sampling to obtain sediment samples; S62, judging whether the sediment samples have submarine cable breakage characteristics.

[0043] If a sediment sample in a certain sample collection point has submarine cable breakage characteristics, the sample collection point is determined as the final corrected fault point; If multiple sediment samples have submarine cable breakage characteristics, the position center point of the multiple sample collection points is taken as the final corrected fault point; If there is no sediment sample with submarine cable breakage characteristics, the existing fault point is taken as the final corrected fault point.

[0044] The sampling range refers to a circular region with the preliminary corrected fault point as the center, which can be specifically delimited by a preset radius value, for example, a radius of 50 meters to 200 meters, and the boundary range is determined by GPS positioning or sonar equipment, which is used to limit the physical space of sediment collection. The submarine cable breakage characteristics refer to the mixed cable metal fragments, insulation layer residues or broken structure traces in the sediment, which can be specifically identified by microscope observation, chemical analysis or spectral detection means, and are used to verify whether there is physical damage evidence around the fault point.

[0045] Compared with the prior art, the traditional method only relies on electrical signal analysis and is prone to misjudgment due to interference of the seabed environment, while the scheme directly verifies whether there is damage evidence around the fault point through physical sample detection, combines electrical positioning with physical evidence, and reduces the error risk of single signal dependence. For example, the prior art may generate false signal peaks due to water flow disturbance, while the scheme can exclude such interference through sediment analysis.

[0046] Through the technical scheme, the application can perform secondary verification on the fault point based on the actual physical state of the seabed, avoid positioning deviation caused by signal distortion or environmental interference, and improve the reliability of fault detection in a complex seabed scene. For example, in a strong ocean current area, the time difference of electrical signal propagation may be affected by flow rate, but the broken features in the sediment can independently confirm the fault location, achieving double verification.

[0047] Through the technical scheme, the application can exclude false correction caused by water flow impact anomalies and avoid marking non-fault areas as fault points. Through physical verification of sediment samples, real faults and signal interference scenarios can be accurately distinguished, and the reliability of fault positioning in a complex seabed environment can be improved. When there are multiple damage features, the geometric center algorithm can eliminate local sampling errors and ensure the spatial consistency of the positioning result with the actual fault area.

[0048] The second aspect of the application discloses a detection system for the fault position of an electrical defect of a submarine cable, comprising: A data acquisition unit is configured to acquire a traveling wave signal of the submarine cable and obtain original signal data. A data decomposition unit is configured to perform data preprocessing on the original signal data to obtain processed signal data, decompose the processed signal data into a low-frequency approximation part and a high-frequency detail part through wavelet transform, and obtain corresponding wavelet transform coefficients. A time difference determination unit is configured to obtain local maximum points on a time axis from the wavelet transform coefficients, obtain modulus maximum points based on the local maximum points, and determine a propagation time difference through the modulus maximum points. An initial fault unit is configured to determine an initial position of a fault point through a ranging equation based on the propagation time difference. A preliminary correction unit is configured to preliminarily correct the initial position based on water flow impact anomalies, and correct the position of the fault point. A final correction unit is configured to collect sediment samples, and obtain a final corrected fault point position from the preliminarily corrected fault point based on submarine cable broken features in the collected sediment samples.

[0049] The following will be further described with specific embodiments: As Figure 1As shown, the application provides a method for detecting the fault position of the electrical defects of the submarine cable, comprising the following steps: S1, high-precision traveling wave acquisition devices are respectively installed at both ends of the submarine cable to sample data of the submarine cable and obtain original signal data; both ends of the submarine cable are set as A end and B end; the data sampling comprises sampling at a low sampling frequency by the traveling wave acquisition device in a normal operation state; and the traveling wave acquisition device samples at a high sampling frequency in an abnormal state.

[0050] S2, the original data is preprocessed to obtain processed signal data; the processing data comprises processing the collected traveling wave signal by using a wavelet threshold denoising method, and calibrating the collected traveling wave signal by using the GPS time information of the two end acquisition devices.

[0051] S3, the processed signal is decomposed into a low-frequency approximate part and a high-frequency detail part by using wavelet transform, and the formula is: (1) In the formula, is a wavelet transform function; t is a time stamp; f(t) is a processed signal; is a wavelet base function; a is a scale parameter, and b is a translation parameter.

[0052] In the low-frequency approximate coefficient and the high-frequency detail coefficient after the wavelet transform, the local maximum value point of the wavelet transform coefficient on the time axis is found to obtain a modulus maximum value point, and the time corresponding to the earliest modulus maximum value point is selected as the time when the signal initial wave head reaches the other end from one end of the submarine cable and is marked as a propagation time difference .

[0053] S4, the length L of the submarine cable is obtained through the propagation time difference, and the signal propagation speed v is calculated through the formula Based on the propagation time difference, the ranging equation is determined by using the double-end traveling wave ranging principle, the position of the fault point is determined according to the ranging equation, and the ranging equation is as follows: (2) In the formula, is the output time of the processed signal at the A end; is the receiving time of the processed signal at the B end; x is the distance from the fault point to the A end; S5, a sub-area is set every standard placement distance on the submarine cable laying path, a buoy device is placed in each sub-area, an elongated flexible rod is connected to the bottom of each buoy device, the bottom end of the flexible rod is fixed to the seabed directly above the submarine cable, and a simple flow direction and flow speed monitoring equipment is installed on the buoy, which is used for recording the flow direction and flow speed data in real time, respectively; Based on the initial position of the fault point, the operation and maintenance personnel are notified to go to the area and the surrounding area to check the flow monitoring data of the buoy device and the marker belt state, and obtain the buoy data, including the flow direction, flow rate, and marker belt position offset; The buoy data is processed and analyzed, including converting the flow direction into a flow angle, and for each sub-area, calculating the parameter difference value through a formula The parameter difference value is calculated ; in the formula, is the i-th buoy parameter, i is the buoy number, and i is a positive integer; is the average value of the buoy parameters in the sub-area; Based on the parameter difference value calculation formula, the flow angle difference, flow rate difference, and marker belt position offset difference of the buoy are calculated, and the flow angle difference, flow rate difference, and marker belt position offset difference are compared with the preset angle difference threshold, flow rate difference threshold, and marker belt position offset difference threshold, respectively. If any parameter difference value is greater than the corresponding difference threshold, it is determined that the buoy has abnormal flow; If more than half of the buoys in the same sub-area have abnormal flow determination results, the sub-area is determined as the preliminary corrected fault point range; If multiple adjacent sub-areas have abnormal flow determination results, the sub-areas are combined as the fault point range; The center position of the fault point range is taken as the preliminary corrected fault point; If none of the parameter difference values is greater than the corresponding difference threshold, the existing fault point marker is taken as the preliminary corrected fault point; S5, based on the preliminary corrected fault point, a sampling range is set with a sampling radius, and multiple seabed sediment sampling devices are deployed inside the sampling range to sample sediments and obtain sediment samples; for example, each sampling device is composed of a cylindrical metal container with an openable and closable sampling bin and a telescopic mechanical arm. The mechanical arm can control the sampling bin to descend to the seabed and collect sediment samples. The sampling depth is set to be within 20 centimeters above and below the submarine cable burial depth position; Determine whether the sediment sample has a submarine cable breaking feature. If there is a sediment sample with a submarine cable breaking feature, the sample collection point is determined as the final corrected fault point; If there are multiple sediment samples with submarine cable breaking features, the position center point of the multiple sample collection points is taken as the final corrected fault point; If there is no sediment sample having the cable breaking feature, the existing fault point is taken as the final modified fault point; for example, the method for judging whether the sediment sample has the cable breaking feature includes judging whether the sediment sample includes abnormal substances such as metal debris, insulating material fragments, etc. in the observation sample, detecting whether the physicochemical properties such as the conductivity and the pH value of the sediment change obviously; if any abnormal situation occurs in a certain sediment sample, the sample collection point is determined as the final modified fault point.

[0054] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable data processing apparatus to produce a computer-implemented process such that the instructions executed on the computer or other programmable data processing apparatus provide steps for implementing the processes specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps in one or more flow or blocks.

[0055] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable data processing apparatus to produce a computer-implemented process such that the instructions executed on the computer or other programmable data processing apparatus provide steps for implementing the processes specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks.

[0056] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable data processing apparatus to produce a computer-implemented process such that the instructions executed on the computer or other programmable data processing apparatus provide steps for implementing the processes specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks.

[0057] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not limited thereto, although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application, any modification or equivalent replacement thereof should be covered within the protection scope of the claims of the present application.

Claims

1. A method for detecting the location of electrical defects in submarine cables, characterized in that: The following steps are involved: S1, collects traveling wave signals from submarine cables to obtain original signal data; S2, performing data preprocessing on the original signal data to obtain processed signal data, decomposing the processed signal data at different scales through wavelet transform, decomposing the processed signal data into a low-frequency approximate part and a high-frequency detail part, and obtaining corresponding wavelet transform coefficients; S3, obtaining the local maximum point on the time axis from the wavelet transform coefficients, obtaining the modulus maximum point based on the local maximum point, and determining the propagation time difference through the modulus maximum point; S4, based on the propagation time difference, determines the initial position of the fault point through the ranging equation; S5, based on the abnormal performance of water flow impact, the initial position is preliminarily corrected to preliminarily correct the fault point location; S6, collecting sediment samples, and obtaining a final corrected fault point location from a preliminary corrected fault point based on the submarine cable breakage characteristics in the collected sediment samples.

2. A method for detecting the location of a submarine cable electrical defect according to claim 1, characterized in that: In S1, the traveling wave signal of the submarine cable is collected by a traveling wave collection device.

3. A method for detecting the location of a submarine cable electrical defect according to claim 1, characterized in that: In S2, the data preprocessing is to perform noise reduction processing on the original signal data to obtain processed signal data.

4. A method for detecting the location of a submarine cable electrical defect according to claim 1, characterized in that: The process of determining the propagation time difference through the modulus maximum point in S3 is as follows: selecting the time corresponding to the earliest modulus maximum point, taking the time as the initial wave head of the signal, and determining the time when the wave head reaches the other end from one end of the submarine cable as the propagation time difference.

5. The method for detecting the location of a submarine cable electrical defect according to claim 1, wherein: In S4, the initial position of the fault point is determined by determining the distance from the fault point to a certain end; The distance calculation formula from the fault point to a certain end is: （2） Where, is the output time of the processing signal at terminal A; is the reception time of the processed signal reaching end B; x is the distance from the fault point to end A.

6. A method for detecting the location of a submarine cable electrical defect according to claim 1, characterized in that: The specific process of S5 is as follows: S51, setting up a sub-area at a standard distance along the cable laying path, and collecting buoy data in each sub-area; the buoy data includes water flow direction, flow velocity, and marker position offset; S52, calculating the parameter differences of the water flow direction, flow velocity, and marker position offset respectively by using a parameter difference calculation formula to obtain the water flow angle difference, flow velocity difference, and marker position offset difference; S53, comparing the preset angle difference threshold of the water flow angle difference, the flow velocity difference and the flow velocity difference threshold, the marker position offset difference and the marker position offset difference threshold. If any parameter difference is greater than the corresponding difference threshold, it is determined that the buoy has abnormal water flow, and S54 is executed. Otherwise, the initial position of the existing fault point is used as the preliminary correction position of the fault point; S54, if the number of buoys in the same sub-area that exceeds the set threshold value shows abnormal water flow judgment results, the sub-area is determined as the fault point range after preliminary correction, and the center position of the fault point range is taken as the preliminary correction fault point.

7. A method for detecting the location of a submarine cable electrical defect according to claim 6, characterized in that: In S54, if abnormal water flow determination results appear in multiple adjacent sub-areas, the multiple sub-areas are merged to form a fault point range, and the center position of the fault point range is taken as the preliminary correction fault point.

8. The method for detecting the location of a submarine cable electrical defect according to claim 1, wherein: The specific process of S6 is as follows: S61, determining a sampling range with the preliminary corrected fault point location as the center of a circle, and performing sediment sampling within the sampling range to obtain a sediment sample; S62, determining whether the sediment sample has characteristics of submarine cable breakage, and obtaining the final corrected fault point location.

9. A method for detecting the location of a submarine cable electrical defect according to claim 8, characterized in that: In S62, the determination of whether the sediment sample has the characteristics of submarine cable breakage and obtaining the final corrected fault point location include the following three situations: Case 1: If the sediment sample has the characteristics of submarine cable breakage, the sampling point of the sediment sample is the final corrected fault point location; Case 2: If there are multiple sediment samples with cable breakage characteristics, the geometric center point of the multiple sample collection points will be used as the final corrected fault point location; Case 3: If there is no sediment sample with the characteristics of submarine cable breakage, the preliminary corrected fault point position is the final corrected fault point.

10. A system for detecting the location of electrical defects in submarine cables, characterized in that: include: A data acquisition unit is used to collect traveling wave signals from submarine cables and obtain original signal data; A data decomposition unit is used to perform data preprocessing on the original signal data to obtain processed signal data, decompose the processed signal data at different scales through wavelet transform, decompose the processed signal data into a low-frequency approximate part and a high-frequency detail part, and obtain corresponding wavelet transform coefficients; A time difference determination unit is used to obtain a local maximum point on the time axis from the wavelet transform coefficient, obtain a modulus maximum point based on the local maximum point, and determine the propagation time difference through the modulus maximum point; An initial fault unit is used to determine the initial position of the fault point using a ranging equation based on the propagation time difference; A preliminary correction unit is used to make preliminary corrections to the initial position based on the abnormal performance of water flow impact and to preliminarily correct the fault point location; The final correction unit is used to collect sediment samples, and obtain the final corrected fault point position from the preliminary corrected fault point based on the submarine cable breakage characteristics in the collected sediment samples.

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