A power distribution line fault accurate positioning method and system

Abstract

The application belongs to the technical field of power systems, and particularly relates to a distribution line fault accurate positioning method and system, which comprises a dynamic updating topology impedance library containing topology structure, line parameters and terminal information; after a fault signal is triggered, multiple terminals cooperatively collect a traveling wave signal and a time stamp and complete integrity verification; after signal preprocessing, a traveling wave front feature point time stamp and a voltage-current amplitude ratio are extracted; in combination with topology impedance library information, a fault correlation branch is determined through time difference, impedance deviation and signal polarity screening; a traveling wave path is traced back and simplified, an actual propagation speed is calculated to preliminarily determine a fault distance; and the distance is corrected according to impedance distribution characteristics and converted into geographic coordinates for output. The application solves the problems of large deviation and high misjudgment rate of traditional positioning methods, improves the accuracy and response speed of fault positioning, shortens fault disposal time, reduces operation and maintenance cost, and guarantees safe and reliable operation of the distribution line.

Description

Technical Field

[0001] This invention belongs to the field of power system technology, and in particular relates to a method and system for accurate fault location in power distribution lines. Background Technology

[0002] Power distribution lines are the core carriers of power transmission in power systems, and their operational stability directly affects the reliability of electricity supply for industrial production and residential use. Especially in oilfield settings, power distribution lines are the core power supply guarantee for oil and gas production. Rapid and accurate fault location is crucial for shortening power outage time, ensuring production continuity, and reducing operation and maintenance costs. Oilfield power distribution lines often have a complex radial topology of "main feeder – multi-level branch lines," with dense branch nodes covering remote areas. They need to supply power to equipment such as pumping units and are affected by outdoor corrosion, electromagnetic interference, and changes in line joints and materials, resulting in multiple impedance abrupt changes. This places extremely high demands on the topology adaptability, anti-interference capabilities, and accuracy of positioning technologies. Traditional positioning technologies are difficult to adapt to, necessitating a targeted positioning solution.

[0003] Current mainstream traditional traveling wave positioning technology has significant limitations in complex power distribution scenarios such as oil fields: First, it uses static line information input, which cannot adapt to aging lines and dynamic changes in operating conditions, resulting in lagging basic data and positioning errors. Second, it relies on a single terminal to collect signals, which is easily affected by signal attenuation and electromagnetic interference in the field, making it easy to lose or distort data and difficult to obtain high-quality raw data. Third, the fault feature extraction dimension is single, and the anti-interference ability is weak, making it difficult to accurately capture effective features from noise. Fourth, it lacks a systematic fault branch screening mechanism, cannot eliminate false reflection wave interference, and has a high misjudgment rate. Fifth, the distance calculation does not consider the change in wave impedance and path complexity, and there is no closed-loop verification, so it cannot achieve accurate mapping from distance to geographical coordinates and cannot provide reliable guidance for operation and maintenance. In summary, traditional technology cannot meet the requirements of "intelligent and accurate full-process" fault location for oil field power distribution lines, and a positioning solution that breaks through the above limitations is urgently needed. Summary of the Invention

[0004] This invention provides a method and system for accurate fault location of power distribution lines, which solves the problems of inaccurate positioning, slow response, and low operation and maintenance efficiency caused by the static nature of line information, the limitations of single terminal collection, weak anti-interference of fault feature extraction, high misjudgment rate of fault branch screening, large deviation of fault distance calculation, and inability to achieve accurate mapping from distance to geographic coordinates in complex power distribution scenarios such as oil fields.

[0005] In a first aspect, the present invention provides a method for accurately locating faults in power distribution lines, comprising:

[0006] Construct a distribution line topology impedance database, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, and record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals before entering them into the distribution line topology impedance database;

[0007] After the distribution line topology impedance library is constructed, when any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0008] The traveling wave signal that passes the verification is preprocessed to extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0009] By combining the information from the power distribution line topology impedance library with the extracted parameters, the fault-related branches are determined through filtering based on time difference, impedance deviation, and signal polarity.

[0010] Tracing the traveling wave path of the fault-related branch and constructing a simplified propagation path from the head to the fault point to the end, calculating the actual propagation speed of the traveling wave, and initially determining the fault distance by combining the feature point timestamps;

[0011] The fault distance is corrected based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, converted into geographical coordinates, and the location result is output.

[0012] In a second aspect, the present invention provides a power distribution line fault precise location system, applied to the power distribution line fault precise location method as described in the first aspect; the power distribution line fault precise location system includes:

[0013] The topology impedance library module is used to construct a distribution line topology impedance library, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, and record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals before entering them into the distribution line topology impedance library.

[0014] The multi-terminal acquisition module is used to trigger an alarm when any transient signal acquisition terminal detects a fault traveling wave signal after the power distribution line topology impedance library is constructed, and synchronize it to other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0015] The signal processing and extraction module is used to preprocess the verified traveling wave signal and extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0016] The fault branch filtering module is used to combine the information from the power distribution line topology impedance library with the extracted parameters, and to determine the fault-related branches by filtering based on time difference, impedance deviation and signal polarity.

[0017] The path tracing initial calculation module is used to trace the traveling wave path of the fault-related branch and construct a simplified propagation path from the head to the fault point to the end, calculate the actual propagation speed of the traveling wave, and initially determine the fault distance by combining the feature point timestamps.

[0018] The distance correction output module is used to correct the fault distance based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, convert it into geographic coordinates, and output the location result.

[0019] Thirdly, the present invention also provides an electronic device, comprising: a memory for storing computer software programs; and a processor for reading and executing the computer software programs, thereby realizing the power distribution line fault accurate location method as described above.

[0020] Fourthly, the present invention also provides a non-transitory computer-readable storage medium storing a computer software program, which, when executed by a processor, implements the power distribution line fault accurate location method described above.

[0021] Fifthly, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the method for accurate fault location of power distribution lines as described above.

[0022] This invention addresses the pain points of traditional positioning methods—namely, by constructing a dynamically updated topological impedance library, employing a multi-terminal collaborative acquisition and synchronous verification mechanism, implementing multi-dimensional feature extraction and progressive fault branch screening, and combining path optimization and wave impedance adaptation correction strategies. This not only fundamentally solves the problems of static line information, limitations of single-terminal acquisition, branch reflection interference, and the impact of wave impedance abrupt changes that lead to high positioning deviations and false positioning rates, but also ensures the reliability of basic positioning data, the high quality of raw data, and the accuracy of fault feature identification. Furthermore, it achieves intelligent full-process management from initial distance calculation to precise mapping of geographical coordinates of fault points, significantly improving the response speed, accuracy, and operational stability of fault location. Ultimately, it provides maintenance personnel with intuitive and accurate fault location guidance, effectively shortening fault handling time, reducing maintenance costs, and ensuring the safe and reliable operation of power distribution lines. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the method for accurately locating power distribution line faults provided in an embodiment of the present invention.

[0024] Figure 2This is a schematic diagram of the structure of the power distribution line fault accurate location system provided in an embodiment of the present invention;

[0025] Figure 3 An embodiment diagram of the electronic device provided in this invention;

[0026] Figure 4 An embodiment diagram of a computer-readable medium provided for an embodiment of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] In the description of this invention, the term "such as" is used to mean "used as an example, illustration, or description." Any embodiment described as "such as" in this invention is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use this invention. In the following description, for purposes of explanation...

[0030] Details are listed. It should be understood that those skilled in the art will recognize that the invention can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the illustrated embodiments, but rather to be consistent with...

[0031] This is consistent with the broadest scope of the principles and features disclosed in this invention.

[0032] See Figure 1 , Figure 1 This is a flowchart illustrating the precise fault location method for power distribution lines provided by the present invention. In this embodiment, the executing entity of the precise fault location method for power distribution lines is a precise fault location system for power distribution lines. Therefore, the precise fault location method for power distribution lines includes:

[0033] Step 10: Construct a distribution line topology impedance database, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals and then enter them into the distribution line topology impedance database.

[0034] Optionally, the control system sorts out the topology relationship at all key nodes of the power distribution line, collects the core parameters of the line, deploys transient signal acquisition terminals, and builds a topology impedance library, and then adopts a dual update mechanism of "periodic update + abnormal trigger update".

[0035] In other words, in addition to setting a fixed periodic update cycle, the database will be updated immediately when the acquisition terminal detects a sudden change in line parameters.

[0036] The collected topology, parameters, and terminal information are organized and entered into a database to form a structured topology impedance library. See steps 101-104 for details.

[0037] Furthermore, this step, through a comprehensive review and dynamic update mechanism, fundamentally ensures the integrity and timeliness of the information in the topological impedance database. This solves the positioning deviation problem caused by the static nature of line information in traditional methods, providing unified and reliable basic data support for all subsequent positioning analysis steps. It is a prerequisite for achieving accurate positioning and significantly improves the credibility of the data source and the reliability of the processing results of the entire system.

[0038] Step 20: After the distribution line topology impedance library is constructed, when any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0039] Optionally, the control system presets a fault traveling wave trigger threshold and a trigger delay to prevent false triggering. When any transient signal acquisition terminal detects a fault traveling wave signal exceeding the preset threshold, it immediately triggers an alarm and synchronizes it to other transient signal acquisition terminals in the same fault monitoring zone via a multi-mode communication link. After each terminal synchronously acquires the transient traveling wave signal and its corresponding timestamp, it uploads it to the positioning host via the communication network. The positioning host performs integrity verification on the uploaded data and removes abnormal data. See steps 201-204 for details.

[0040] Furthermore, this step, through a multi-terminal collaborative acquisition and synchronous verification mechanism, ensures the timeliness and integrity of fault signal acquisition. This process effectively avoids the limitations of single-terminal acquisition, solves the data loss problem caused by signal attenuation or interference in traditional single-terminal acquisition, and provides high-quality raw data for subsequent signal processing and feature extraction, which is a key data guarantee for achieving accurate positioning.

[0041] Step 30: Preprocess the verified traveling wave signal to extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0042] Optionally, the control system first performs combined filtering on the verified traveling wave signal to effectively remove environmental electromagnetic interference, mechanical vibration conducted noise, and sensor background noise, obtaining a purified signal. Subsequently, the feature extraction module extracts key parameters that can characterize fault features from the purified signal, including the timestamp of the traveling wave leading edge feature point and the voltage-current amplitude ratio. After standardizing these feature parameters, operating condition feature information is formed. See steps 301-304 for details.

[0043] Furthermore, this step utilizes combined filtering and feature extraction techniques to transform the raw, noisy sensor readings into refined feature information that characterizes the fault state. This process effectively removes environmental interference, highlights key information closely related to fault location, provides accurate feature basis for subsequent fault association branch selection, avoids feature misjudgment caused by signal noise, and improves the accuracy of fault location.

[0044] Step 40: Combining the information from the power distribution line topology impedance library with the extracted parameters, the fault-related branches are determined by filtering based on time difference, impedance deviation, and signal polarity.

[0045] Optionally, the control system uses the extracted operating condition feature information as a basis, combined with topological impedance library information, to determine the fault-related branches through multi-dimensional screening.

[0046] First, a preliminary screening of time differences is performed by calculating the time difference between characteristic points between terminals and comparing it with the theoretical time difference range to retain candidate fault branches. Next, a secondary screening of impedance deviation is performed, using the voltage-current amplitude ratio deviation threshold as a standard to eliminate branches with no fault risk. Finally, a final screening of signal polarity is performed by comparing the signal polarity of the beginning and end terminals of the candidate branches to identify fault-related branches and eliminate false reflection interference. See steps 401-403 for details.

[0047] Furthermore, this step employs a multi-dimensional, progressive filtering mechanism to accurately pinpoint the fault-related branch from multiple line branches. This process effectively eliminates interference from non-faulty branches, resolves the problem of misjudging faulty branches due to branch reflection in traditional methods, narrows the range for subsequent fault point distance calculations, and improves positioning efficiency and accuracy.

[0048] Step 50: Trace the traveling wave path of the fault-related branch and construct a simplified propagation path from the head to the fault point to the end. Calculate the actual propagation speed of the traveling wave and determine the fault distance by combining the feature point timestamps.

[0049] Optionally, the control system traces the propagation path of the fault traveling wave within the fault-related branch based on the topological impedance library information, clarifying the propagation trajectory of the fault traveling wave; it ignores non-critical small wave impedance abrupt changes on the line, constructing a simplified propagation path of "branch head - fault point - branch end"; it calculates the actual propagation speed of the traveling wave based on the line parameters; and it initially determines the distance to the fault point based on the time difference of the characteristic point and the actual propagation speed. See steps 501-504 for details.

[0050] Furthermore, this step provides a reliable basis for the initial calculation of the fault point distance through path simplification and accurate velocity calculation. This process effectively avoids interference from non-critical factors in the distance calculation, solves the problem of distance calculation deviation caused by the complexity of the propagation path in traditional methods, lays the foundation for subsequent distance correction, and improves the initial accuracy of fault point location.

[0051] Step 60: Correct the fault distance based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, convert it into geographic coordinates, and output the location result.

[0052] Optionally, the control system extracts the wave impedance distribution data of the fault-related branch from the topology impedance library to determine the wave impedance continuity in the area where the fault point is located. If there is a sudden change in wave impedance, a correction coefficient is introduced to correct the actual propagation speed of the traveling wave. The corrected speed is substituted into the distance formula to recalculate the corrected distance to the fault point. The installation coordinates of the first terminal of the fault-related branch are retrieved, and the geographical coordinates of the fault point are calculated through coordinate system transformation in combination with the line route. The positioning host integrates the fault location information, displays it through the monitoring platform, and pushes it to the operation and maintenance terminal. See steps 601-604 for details.

[0053] Furthermore, this step achieves a precise mapping of the fault point from distance to actual location through impedance matching correction and geographic coordinate transformation. This process effectively compensates for the impact of sudden changes in impedance on distance calculation, solves the positioning error problem caused by ignoring differences in line parameter distribution in traditional methods, and finally provides maintenance personnel with intuitive and accurate fault location guidance through the output geographic coordinates, significantly improving fault handling efficiency.

[0054] This invention addresses the pain points of traditional positioning methods—namely, by constructing a dynamically updated topological impedance library, employing a multi-terminal collaborative acquisition and synchronous verification mechanism, implementing multi-dimensional feature extraction and progressive fault branch screening, and combining path optimization and wave impedance adaptation correction strategies. This not only fundamentally solves the problems of static line information, limitations of single-terminal acquisition, branch reflection interference, and the impact of wave impedance abrupt changes that lead to high positioning deviations and false positioning rates, but also ensures the reliability of basic positioning data, the high quality of raw data, and the accuracy of fault feature identification. Furthermore, it achieves intelligent full-process management from initial distance calculation to precise mapping of geographical coordinates of fault points, significantly improving the response speed, accuracy, and operational stability of fault location. Ultimately, it provides maintenance personnel with intuitive and accurate fault location guidance, effectively shortening fault handling time, reducing maintenance costs, and ensuring the safe and reliable operation of power distribution lines.

[0055] In one embodiment, steps 101-104 are described as follows:

[0056] Step 101: Organize the power distribution line topology.

[0057] Optionally, a dual verification mode of "drawing analysis + on-site measurement" can be adopted to carry out topology sorting work.

[0058] First, retrieve the CAD drawings of the power distribution line design, and use professional vectorization analysis tools to extract the routing information of the main feeder and branch lines at all levels, clarify the design coordinates of the branch nodes, conductor types and connection relationships between nodes, and form a preliminary topology draft.

[0059] Subsequently, on-site measurements and verifications were carried out. High-precision positioning equipment was used to accurately locate branch nodes and line corners. Combined with distance measuring equipment, the length of each line segment was measured segment by segment to correct the deviation between the drawings and the actual working conditions. Key information such as the distribution location, model specifications, and aging status of line joints were recorded simultaneously.

[0060] Finally, the sorted and verified information is organized into a structured topology table containing fields such as line ID, start and end node coordinates, actual length, conductor type, and joint information. This ensures the integrity and accuracy of the basic topology data and provides reliable core topology support for the subsequent construction of the topology impedance library.

[0061] Step 102: Collect core parameters of the line.

[0062] Optionally, a standardized process of "segmented acquisition + multi-point verification + data validation" can be used to acquire the core parameters of the line.

[0063] For the wave impedance parameter, a high-precision impedance tester was used to perform multiple measurements at both ends of each line segment. The average value was taken as the initial wave impedance value of that line segment. The ambient temperature and humidity data during the test were recorded simultaneously for subsequent parameter temperature compensation correction.

[0064] To determine the reference value for traveling wave propagation speed, the initial speed is first calculated by referring to the theoretical values ​​of inductance and capacitance per unit length in the conductor parameter manual. Then, the speed is corrected by actual measurement through on-site traveling wave calibration tests to ensure that the speed error is controlled within the preset accuracy range.

[0065] After data collection, an outlier detection algorithm is used to detect and remove outliers from all parameter data, ultimately forming a standardized list of line parameters containing information such as line segment ID, wave impedance, traveling wave propagation speed, and temperature and humidity correction coefficients. This provides accurate parameter support for subsequent core steps such as fault distance calculation and theoretical propagation time measurement.

[0066] Step 103: Divide the monitoring zones and deploy terminals.

[0067] Optionally, monitoring zones can be divided based on the three-dimensional principle of "load density + topology + communication coverage".

[0068] Prioritize dividing areas with concentrated industrial loads and high probability of failure into independent monitoring zones, ensuring that each zone contains a complete "main feeder-branch line" unit, and at the same time check the communication network coverage within the zone to ensure the stability of terminal data transmission.

[0069] After the partitioning is completed, transient signal acquisition terminals with built-in dual synchronization modules are deployed at key nodes such as the beginning and end of the main feeder, branch forks, and heavy-load sections of the line to ensure that the time synchronization accuracy between terminals meets the positioning requirements.

[0070] During deployment, the unique identifier, latitude and longitude installation coordinates, monitoring zone and topology of each terminal are recorded in detail to form a terminal deployment list that has been verified on-site, providing basic information support for subsequent multi-terminal collaborative data collection and accurate time difference calculation.

[0071] Step 104: Build and update the topological impedance library.

[0072] Optionally, a topology impedance library can be built using a distributed database architecture. The library contains three core data tables: a topology structure table, a line parameter table, and a terminal information table. A correlation index is established using line ID and unique terminal identifier to improve the efficiency of data query and retrieval.

[0073] The previously identified topology relationships, collected line parameters, and terminal deployment information are categorized and entered into the corresponding data tables. During the entry process, a data verification mechanism is enabled to check the rationality of the topology logic, the validity of the parameter values, and the uniqueness of the terminal information, ensuring that the data entered into the database is accurate.

[0074] A dual update mechanism of "regular updates + parameter mutation anomaly triggered updates" is established. When the terminal detects a line parameter mutation exceeding the preset threshold, an alarm is immediately triggered. After on-site verification, the operation and maintenance personnel manually update the data in the database to ensure that the topology impedance database data matches the actual line conditions in real time, avoiding subsequent positioning errors due to data lag.

[0075] In one embodiment, steps 201-204 are described as follows:

[0076] Step 201: Preset fault trigger threshold.

[0077] Optionally, by combining historical fault data statistics and simulation test verification, a fault traveling wave trigger threshold can be scientifically preset.

[0078] First, retrieve the fault recording data of the power distribution line within the preset number of years, and count the voltage and current surge peaks corresponding to different fault types (short circuit, grounding, etc.). Take the preset proportion of the minimum peak value of each type of fault as the initial threshold.

[0079] Then, by simulating different load conditions and fault locations using simulation models, the sensitivity and anti-interference capability of the initial threshold are verified, and the preset voltage change threshold and preset current change threshold are finally determined.

[0080] Meanwhile, the system is equipped with an adaptive threshold adjustment function, which can dynamically fine-tune the threshold range according to the real-time load changes of the line, effectively avoiding false alarms caused by load fluctuations and ensuring the accuracy and reliability of fault signal capture.

[0081] Step 202: Fault triggering and alarm synchronization.

[0082] Optionally, when any transient signal acquisition terminal detects that the voltage or current signal exceeds the preset trigger threshold, it immediately activates a local audible and visual alarm and simultaneously sends a synchronous alarm command to other terminals in the same monitoring zone via a multi-mode communication link.

[0083] A data transmission priority mechanism is adopted, setting alarm commands to the highest priority to ensure that their transmission speed is better than that of ordinary data, and to ensure that alarm synchronization of all terminals in the partition is completed within a preset time.

[0084] The synchronization command contains key information such as the trigger terminal ID, the initial fault timestamp, and the amplitude of the signal mutation. Other terminals activate the acquisition module immediately after receiving the command to avoid missing fault traveling wave signals due to startup delays.

[0085] Step 203: Collaboratively acquire signals and timestamps.

[0086] Optionally, after each terminal is activated, it can perform synchronous acquisition according to preset sampling parameters to ensure complete capture of the leading edge and subsequent waveforms of the fault traveling wave.

[0087] The terminal uses a built-in dual synchronization module to mark each sampling point with a timestamp that meets the accuracy requirements. At the same time, a master-slave synchronization mechanism is adopted, designating the main feeder head terminal as the master terminal and sending time calibration signals to each slave terminal at a preset cycle to correct the time deviation between terminals.

[0088] After data acquisition, the terminal performs local circular buffering of the raw data and carries out preliminary preprocessing (removing DC components of the signal) to avoid data loss or contamination, laying a solid foundation for subsequent data upload and integrity verification.

[0089] Step 204: Data upload and integrity verification.

[0090] Optionally, each terminal uploads the cached collected data to the positioning host in segments through a preset communication link. During the upload process, a CRC32 checksum mechanism is used to ensure the integrity of data transmission.

[0091] After receiving the data, the positioning host initiates a three-layer integrity check: the first layer checks the matching of the number of bytes of uploaded data with the preset acquisition parameters; the second layer traverses the data frame sequence number to determine whether there are any missing data frames; the third layer uses a threshold filtering method to remove extreme data caused by sensor failure.

[0092] After verification, a data verification report is generated, clearly marking valid data and abnormal data. A retransmission command is sent to terminals with missing data. If the retransmission fails, the terminal's data is marked as invalid.

[0093] Finally, all valid data are integrated to form a standardized raw data file, which is used for subsequent traveling wave signal preprocessing.

[0094] In one embodiment, steps 301-304 are described as follows:

[0095] Step 301, Filtering and purification process.

[0096] Optionally, a combination of "power frequency notch filtering + wavelet threshold filtering" can be used to purify the acquired raw signal, effectively removing environmental electromagnetic interference, mechanical vibration transmission noise and sensor background noise.

[0097] First, use a power frequency notch filter to accurately remove power frequency and harmonic interference, ensuring that the power frequency interference is attenuated to a negligible range.

[0098] Then, a preset wavelet basis is used to perform multi-level decomposition on the signal after power frequency removal, and the wavelet coefficients of each level are denoised by an improved threshold function to suppress high-frequency noise components.

[0099] Finally, the processed wavelet coefficients are reconstructed by inverse transform to obtain the purified fault traveling wave signal.

[0100] After filtering is completed, the signal-to-noise ratio (SNR) is used to evaluate the filtering effect, ensuring that the SNR meets the requirements for subsequent feature extraction and providing a high-quality signal foundation for subsequent fault feature extraction.

[0101] Step 302: Wavelet transform decomposes the signal.

[0102] Optionally, the filtered and purified signal is decomposed using a multi-layer preset wavelet basis, and the separation of signals in different frequency bands is achieved through multi-resolution analysis.

[0103] The low-frequency components mainly contain information about normal line operation, while the high-frequency detail components contain information about fault traveling wave characteristics.

[0104] By calculating the energy values ​​of the high-frequency detail components of each layer, several adjacent frequency bands with the highest energy are selected as the core frequency bands of the fault traveling wave. The high-frequency detail components of the corresponding frequency bands are merged, and irrelevant low-frequency and high-frequency noise is further removed to highlight the characteristics of the fault traveling wave.

[0105] Simultaneously, the amplitude and phase information of wavelet coefficients at each layer are recorded, providing auxiliary judgment basis for the accurate identification of subsequent traveling wave front feature points and improving the accuracy of feature identification.

[0106] Step 303: Identify feature points and record timestamps.

[0107] Optionally, a combination of "modulus maxima detection + threshold judgment" can be used to identify feature points of the traveling wave front.

[0108] First, calculate the local modulus maxima of the core frequency band signal, set a preset proportion of the maximum modulus maxima of the signal as the feature point recognition threshold, and filter out candidate feature points that exceed the threshold.

[0109] Then, by calculating the amplitude change rate of adjacent candidate feature points, the point with the largest change rate is selected as the final traveling wave leading edge feature point.

[0110] Record the timestamp corresponding to the feature point and start the synchronization verification mechanism. If the synchronization deviation between the timestamp and other terminals exceeds the preset range, it will be corrected immediately.

[0111] An interpolation algorithm is used to fit several consecutive sampling points near the feature point to optimize the timestamp accuracy, providing a core guarantee for the accurate calculation of the subsequent time difference.

[0112] Step 304: Calculate the voltage-current amplitude ratio.

[0113] Optionally, based on the precise feature point timestamp, the voltage amplitude and current amplitude at the corresponding moment are accurately extracted from the purified signal, and the ratio of the two is calculated to obtain the voltage-current amplitude ratio.

[0114] Before calculation, a timestamp calibration mechanism is used to eliminate sampling delay deviations between terminals, ensuring the synchronization of voltage and current sampling.

[0115] Since there is a one-to-one correspondence between the voltage-current amplitude ratio and the line impedance, this ratio can directly reflect the matching state of the line impedance: when there is no fault, the amplitude ratio is stable within the normal range, and when there is a fault, it will deviate from the normal range due to the sudden change in impedance.

[0116] The calculated amplitude ratio is associated with and stored along with the feature point timestamp and the corresponding line segment ID to form a standardized list of feature parameters, providing a quantitative basis for subsequent impedance deviation screening of faulty branches. See steps 3041-3043 for details.

[0117] In one embodiment, steps 3041-3043 are described as follows:

[0118] Step 3041: Accurately record the timestamp.

[0119] Optionally, a high-precision timestamp recording process can be initiated to ensure the accuracy and synchronization of feature point timestamps.

[0120] First, retrieve the high-precision real-time time of the terminal after calibration by the dual synchronization module, accurately map the sampling point number corresponding to the feature point to the real-time time, and calculate the initial timestamp by combining it with the preset sampling frequency.

[0121] Then, an interpolation algorithm is used to fit several consecutive sampling points near the feature point to correct the error of the initial timestamp and obtain a high-precision timestamp.

[0122] A timestamp record table is formed by associating the precise timestamp with the corresponding terminal ID and line segment ID. The table is compared with the terminal's standard time in real time. If a deviation occurs, a correction is initiated immediately, providing a core time reference for the accuracy of subsequent voltage-current amplitude ratio calculations.

[0123] Step 3042: Calculate the voltage-current amplitude ratio.

[0124] Optionally, based on the synchronized high-precision timestamp, the peak voltage and current amplitudes at the corresponding moment can be accurately extracted from the filtered and purified signal.

[0125] By traversing several sampling points before and after the timestamp, the peak voltage and peak current are accurately extracted using a peak detection algorithm, and the ratio of the two is calculated to obtain the voltage-current amplitude ratio.

[0126] During the calculation process, a numerical verification mechanism is enabled. If the amplitude ratio result exceeds the preset multiple of the normal range of the wave impedance of the corresponding line segment, it is determined to be abnormal data, and the process automatically returns to step 303 to re-identify feature points and record timestamps.

[0127] The effective amplitude ratio is associated with and stored with the corresponding timestamp, terminal ID, and line segment ID to form a standardized feature parameter dataset, providing accurate quantitative data support for subsequent impedance deviation analysis.

[0128] Step 3043: Analyze the amplitude ratio deviation.

[0129] Optionally, the standard value of the wave impedance of the current line segment can be retrieved from the topology impedance library, and the deviation value and deviation rate between the voltage-current amplitude ratio and the standard value of the wave impedance can be calculated.

[0130] Based on the line's years of operation, several deviation level thresholds are preset: a deviation rate within the first preset range is considered normal (good wave impedance matching); a deviation rate within the second preset range is considered slightly abnormal (potentially indicating loose connections); and a deviation rate exceeding the second preset range is considered seriously abnormal (highly likely indicating short circuits, grounding, or other faults).

[0131] By assessing the impedance matching status of the output line waveform using deviation levels, line segments marked as severely or slightly abnormal are prioritized for monitoring and recorded in the fault diagnosis log for subsequent traceability. This analysis provides a clear basis for screening impedance deviations in subsequent faulty branches, effectively narrowing down the scope of fault investigation.

[0132] In one embodiment, steps 401-403 are described as follows:

[0133] Step 401: Initial screening of time differences.

[0134] Optionally, by combining the parameters of the topological impedance library to conduct multi-terminal time difference comparison and screening, the range of candidate fault branches can be significantly narrowed.

[0135] First, extract the length deviation value of the target line segment (the difference between the designed length and the measured length) and the reference value of the traveling wave propagation speed (calculated by the correlation of inductance and capacitance per unit length) from the topology impedance library. Then, obtain the theoretical propagation time range of the traveling wave through the correlation calculation between the two.

[0136] Next, extract the timestamps of the characteristic points of the traveling wave leading edge of each transient signal acquisition terminal, and calculate the absolute value of the time difference between any two terminals according to the "pair pairing" principle to form a set of actual time differences. Compare the actual time differences with the theoretical propagation time range one by one, and retain the branches whose actual time differences fall within the theoretical range as candidate fault branches.

[0137] This screening process can effectively eliminate a large number of non-faulty branches, reduce invalid calculations in subsequent screening stages, improve overall screening efficiency, and lay the foundation for accurately identifying faulty branches. See steps 4011-4013 for details.

[0138] Step 402, secondary screening of impedance deviation.

[0139] Optionally, a secondary screening can be conducted using the voltage-current amplitude ratio as the core quantitative indicator, combined with the standard value of the topological impedance Coulomb impedance, to further eliminate branches with no risk of failure.

[0140] The standard wave impedance values ​​of each candidate branch are retrieved from the topology impedance library, and the differential deviation range is preset according to the line's commissioning years.

[0141] Calculate the deviation rate between the voltage-current amplitude ratio of each candidate branch and the corresponding standard value of the wave impedance. Branches with deviation rates exceeding the preset range are identified as high-risk branches, while branches with deviation rates within the preset range are retained.

[0142] This step effectively eliminates false fault signal branches caused by normal aging of the line or slight loosening of the connectors, improving the accuracy of candidate fault branches and providing a more reliable list of branches for the final screening.

[0143] Step 403: Final screening of signal polarity.

[0144] Optionally, by comparing the signal polarity of the first and last terminals of the candidate fault branches, the fault-related branches can be locked using the fault traveling wave propagation characteristics, thus eliminating false reflection wave interference.

[0145] First, extract the fault traveling wave core frequency band signal waveforms at the beginning (close to the main feeder end) and the end (far from the main feeder end) of the candidate branch to ensure that the waveform sampling duration meets the analysis requirements and contains complete traveling wave front characteristics.

[0146] The zero-phase point is determined by the "zero-crossing detection + phase fitting" method: the initial zero-crossing point transitioning from negative to positive is found by traversing the signal sequence, and then the signal near the point is curve-fitted by the fitting algorithm to obtain the precise zero-phase point time.

[0147] Using the zero-phase point as a reference, the polarity is determined by judging the sign of the signal amplitude at a preset time. According to the propagation law of fault traveling waves, the polarities of the signals at the beginning and end of the fault branch are opposite, while the polarities of the non-fault branches (only reflected waves) are the same. Based on this, branches with opposite polarities are selected as fault-related branches. See steps 4031-4033 for details.

[0148] In one embodiment, steps 4011-4013 are described as follows:

[0149] Step 4011: Calculate the theoretical propagation time range.

[0150] Optionally, a standardized process of "parameter retrieval + correlation calculation + data verification" can be adopted to accurately obtain the propagation time range of traveling wave theory.

[0151] Retrieve the design length and measured length of the target line segment, as well as the inductance and capacitance parameters per unit length of the matching conductor type, from the topology impedance library to ensure that the parameters correspond one-to-one with the line segment.

[0152] First, calculate the difference between the designed length and the measured length to obtain the deviation value of the line segment length, and at the same time, eliminate abnormal data in the inductance and capacitance parameters.

[0153] Based on electromagnetic propagation theory, the reference value of traveling wave propagation speed is obtained by calculating the correlation between inductance and capacitance per unit length. Then, the propagation time range of traveling wave theory is obtained by correlating the length deviation value with the reference speed.

[0154] After the calculation is completed, a rationality check is performed to ensure that the range is within the normal propagation time interval of this type of line. This range will serve as the core benchmark for subsequent comparison of actual time differences, providing a quantitative standard for preliminary screening.

[0155] Step 4012: Compare the actual and theoretical time differences.

[0156] Optionally, after completing the calculation and preprocessing of the actual time difference, a precise comparison with the theoretical range can be carried out.

[0157] Extract the timestamps of the characteristic points of the traveling wave leading edge of all terminals in the candidate branch, calculate the absolute value of the time difference between any two terminals according to the "pair pairing" principle, form the actual time difference set, and label the terminal pairing and line segment information corresponding to each time difference.

[0158] An outlier detection algorithm is used to remove extreme value data from the set to avoid outlier data interfering with the comparison results.

[0159] Subsequently, a one-to-one comparison mode was adopted to match each preprocessed actual time difference with the theoretical propagation time range, and a threshold was set for the percentage of actual time differences falling within the theoretical range.

[0160] If the compliance rate of a candidate branch reaches the threshold, it is determined to pass the comparison; otherwise, it is marked as a branch to be removed, providing a clear basis for subsequent branch removal work.

[0161] Step 4013: Remove branch lines that are out of range.

[0162] Optionally, based on the results of the previous comparison, branch elimination and list optimization can be carried out to ensure the reliability of candidate branches.

[0163] Candidate branches that clearly fail the comparison should be removed directly from the list, and the reasons for removal should be recorded in detail (such as the proportion of time difference that failed the comparison, extreme value data, etc.) to facilitate subsequent traceability and verification.

[0164] For branches whose comparison results are in a critical state (the proportion of compliance is close to the threshold), a secondary verification process is initiated to retrieve the terminal timestamp and theoretical range data again, repeat the calculation and comparison, and remove branches that fail the secondary verification.

[0165] After the elimination process is completed, the key information such as the line ID, monitoring zone, and terminal configuration of the remaining branches is sorted out to form a simplified candidate list.

[0166] If all branches fail the comparison, it is determined that the previous feature point identification was biased, and the process will automatically return to step 303 to start the work again, ensuring that subsequent screening is based on reliable data.

[0167] In one embodiment, steps 4031-4033 are described as follows:

[0168] Step 4031: Extract the waveforms of the first and last signals.

[0169] Optionally, the signal waveforms of the first and last terminals of the candidate fault branch can be accurately extracted to provide complete and effective basic data for polarity determination.

[0170] Retrieve the core frequency band signal data of the fault traveling wave from the valid data file of the positioning host, specifically from the first end (close to the main feeder) and the last end (far from the main feeder) of the candidate branch. Ensure that the sampling duration of the retrieved waveform data meets the analysis requirements and can fully include the leading edge characteristics, peak value, and subsequent attenuation segment of the fault traveling wave.

[0171] The retrieved waveform data undergoes a preliminary integrity check to verify for missing data, broken frames, or other issues. If any are found, the terminal data retransmission process is initiated; if retransmission fails, the candidate branch is removed. The verified waveform data is then stored according to the terminal affiliation, labeled with the corresponding branch ID, terminal ID, and acquisition time, to prepare data for subsequent zero-phase point determination and polarity assessment.

[0172] Step 4032: Determine the zero phase point and determine the polarity.

[0173] Optionally, a combination of "zero-crossing detection + phase fitting + accuracy verification" is adopted to ensure the accuracy of the zero-phase point and the reliability of polarity determination. Effective data segments of the core frequency band signal at the beginning and end terminals are extracted, and the initial zero-crossing point where the amplitude transitions from negative to positive is located by traversing the signal sequence, recording its initial time and amplitude.

[0174] Curve fitting is performed on sampling points near the initial zero-crossing point. The fitting parameters are optimized using a fitting algorithm to obtain an accurate waveform fitting curve. The precise zero-phase point time is then determined based on the curve. Using this time as a benchmark, a preset judgment time that avoids the signal transition region is selected. The polarity is determined by judging the positive or negative signal amplitude at this time (positive polarity, negative polarity). The rate of change of signal amplitude before and after the zero-phase point is calculated. If the rate of change is lower than a threshold, signal distortion is determined, and the waveform is re-extracted for analysis; if it meets the threshold, the polarity is confirmed to be valid, providing a core basis for the comparison between the beginning and end points.

[0175] Step 4033: Filter branches with opposite polarities.

[0176] Optionally, the final identification of the fault-related branch can be completed by comparing the polarity of the signals at the beginning and end terminals.

[0177] The polarity of the first terminal obtained in step 4032 is compared with the polarity of the last terminal one by one, and the target branch is selected according to the propagation characteristics of the fault traveling wave: when there is a fault in the line, the fault traveling wave propagates from the fault point to both ends, and the polarity of the signals received by the first and last terminals must be opposite; if there is no fault in the line, and there is only reflected wave interference, the polarity of the signals of the first and last terminals remains the same.

[0178] Based on this pattern, candidate branches with opposite polarities at the beginning and end of the signal are selected and identified as fault-related branches. At the same time, branches with the same polarity are eliminated to completely remove interference from pseudo-reflected waves, ensuring that the finally locked fault-related branches are accurate and providing reliable branch objects for subsequent fault distance calculation.

[0179] In one embodiment, steps 501-504 are described as follows:

[0180] Step 501: Trace the propagation path of the fault traveling wave.

[0181] Optionally, the propagation trajectory of the fault traveling wave can be accurately traced based on topological impedance library data and terminal timestamp sequences.

[0182] Retrieve complete topology data of fault-related branches from the topology impedance library, clarify node connection relationships, line segment affiliation, terminal deployment location and direction, and construct a visualized topology map.

[0183] The timestamps of the fault traveling wave signals collected by each terminal are sorted in time sequence, and the direction of traveling wave propagation is preliminarily determined by combining the spatial distribution of the terminals.

[0184] By combining the reflection and refraction patterns of traveling waves at branch nodes, the complete trajectory of the fault traveling wave propagating from the fault point to the surrounding terminals is deduced. In the process, the pseudo propagation paths caused by branch reflection are investigated and eliminated.

[0185] Through multiple rounds of time series analysis and trajectory deduction verification, the precise propagation path of the fault traveling wave was finally determined, providing accurate path basis for subsequent path simplification and distance calculation, and ensuring the accuracy of distance calculation.

[0186] Step 502: Construct a simplified propagation path.

[0187] Optionally, based on the complete propagation path, the path can be simplified according to the principle of "simplifying the complex and retaining the core", thereby reducing the complexity of subsequent distance calculations.

[0188] A comprehensive analysis of the entire propagation path was conducted to identify core nodes and non-critical interference factors: core nodes include the beginning of a branch, the fault point, the end of the branch, and major branch nodes; non-critical factors include minor joints, slight differences in local materials, and short-distance line bends (their impact on traveling wave propagation is negligible).

[0189] Eliminate non-critical interference factors, retain core nodes and the main line segments between each node, and discard redundant path details.

[0190] Based on the retained core nodes and main line segments, a standardized simplified path of "branch start point - fault point - branch end point" is constructed, clearly defining key parameters such as the length and direction of each segment in the simplified path. The simplified path is compared and verified with the complete path to ensure that the core characteristics of traveling wave propagation are not changed, guaranteeing that subsequent distance calculations can accurately reflect the actual location of the fault point.

[0191] Step 503: Calculate the actual propagation speed of the traveling wave.

[0192] Optionally, the traveling wave propagation speed that fits the actual working conditions can be accurately obtained through a combination of theoretical calculation and actual correction.

[0193] Retrieve the unit length inductance and capacitance parameters of each main line segment of the fault-related branch from the topology impedance library to ensure that the parameters are accurately matched with the line segment.

[0194] Based on electromagnetic propagation theory, the theoretical value of traveling wave propagation speed is calculated through the correlation between inductance and capacitance. Considering that environmental factors such as temperature and humidity can affect line parameters and thus lead to speed deviations, the theoretical value needs to be corrected by combining actual signal data.

[0195] Extract the time difference of the leading edge feature points of each terminal signal, and combine it with the line length between terminals in the simplified path to calculate the actual observed value of the traveling wave propagation speed.

[0196] By comparing theoretical and observed values, analyzing the deviation patterns, and introducing an environmental influence correction coefficient to iteratively correct the theoretical velocity, the actual propagation velocity of the traveling wave that conforms to the actual working conditions is finally obtained, providing core and accurate parameters for the initial calculation of fault distance.

[0197] Step 504: Initial calculation of the distance to the fault point.

[0198] Optionally, the initial distance to the fault point can be calculated based on accurate actual propagation speed and timestamp data of the traveling wave.

[0199] The system analyzes the fault signal timestamps of all terminals, removes abnormal data, sorts the valid timestamps in sequence, and determines the earliest timestamp as the fault trigger time (corresponding to the precise time of fault occurrence).

[0200] Extract the timestamp of the leading edge feature point of the traveling wave at the first terminal of the fault-related branch (the first terminal has higher stability), calculate the difference between the fault trigger time and the timestamp, and obtain the time difference of the traveling wave propagating from the fault point to the first terminal.

[0201] Combining the actual propagation speed of the traveling wave obtained in step 503, the initial distance between the fault point and the first terminal is obtained through the correlation calculation between time difference and speed.

[0202] The initial distance is validated to ensure it is within the length range of the fault-related branch. If it exceeds this range, the previous steps are returned and the initial distance is recalculated. This initial distance provides the basis for subsequent distance correction.

[0203] In one embodiment, steps 601-604 are described as follows:

[0204] Step 601: Extract wave impedance data and determine continuity.

[0205] Optionally, wave impedance data extraction and continuity analysis can be carried out based on the topological impedance library to clarify the direction of distance correction.

[0206] Retrieve the standard wave impedance values ​​(accurate data verified by multiple field tests) of each line segment of the fault-related branch from the topology impedance library, and record key information affecting wave impedance such as conductor type, service life, and joint distribution of each line segment.

[0207] By associating standard wave impedance values ​​with corresponding line segments, a wave impedance distribution map of fault-related branches is constructed, clearly presenting the wave impedance values ​​and distribution of each segment. A segmented continuity analysis method is used to calculate the wave impedance difference between adjacent line segments, and a continuity judgment threshold is set based on the line material and service life.

[0208] If the difference is within the threshold range, the impedance is determined to be continuous; if it exceeds the threshold, a sudden change is determined. This allows for precise location of the fault point and provides a clear basis for developing differentiated correction strategies.

[0209] Step 602, correct the fault distance.

[0210] Optionally, based on the results of wave impedance continuity analysis, a differentiated strategy is adopted to correct the initial distance and compensate for the influence of differences in line parameter distribution. For cases where the fault point is located in an impedance continuity region, since the traveling wave propagation speed is stable, only a small error correction is needed: a small correction coefficient is determined by combining factors such as line measurement accuracy and signal acquisition error, and the corrected distance is obtained by calculating the correlation between the initial distance and the coefficient.

[0211] For cases where the fault point is located in a region of abrupt change in wave impedance, since the abrupt change in wave impedance will cause a change in propagation speed, it is necessary to introduce an additional correction factor (calibrated by experimental data) related to the amplitude of the abrupt change, on the basis of the small correction factor. The corrected distance is obtained by combining the initial distance with the two factors.

[0212] All correction coefficients are determined based on the topological impedance library and experimental data to ensure the scientific validity of the corrections. The corrected distances are closer to the actual locations, providing high-quality data for coordinate transformation.

[0213] Step 603: Convert geographic coordinates.

[0214] Optionally, a standardized coordinate system transformation process can be used to convert the corrected relative distance into absolute geographic coordinates, achieving a precise mapping between "relative distance and actual location". High-precision GPS coordinates (longitude and latitude) and route angle (angle with true north) of the fault-related branch's first-end terminal are retrieved from the topology impedance library.

[0215] A local planar coordinate system is constructed with the coordinates of the initial terminal as the origin. Combining the corrected distance and orientation angle of the fault point, trigonometric functions are used to calculate the relative coordinates of the fault point in the local coordinate system. Considering the impact of Earth's curvature on large-scale positioning, an Earth curvature correction coefficient is introduced. Using geodetic coordinate system transformation formulas and local geodetic reference surface parameters, the local relative coordinates are converted to globally universal geographic coordinates. After conversion, the coordinates are compared and verified with the coordinates of surrounding known landmarks to ensure that the error is within a preset range, providing intuitive guidance for maintenance personnel to locate fault points on-site.

[0216] Step 604: Output the positioning results.

[0217] Optionally, the core information of the entire fault location process can be integrated and formatted, and output through multiple channels to provide accurate guidance for operation and maintenance work.

[0218] The system integrates core information such as fault-related branch ID, corrected fault distance, precise geographic coordinates, positioning time, and positioning accuracy level, and processes it according to the data specifications of the industrial monitoring platform to generate a standardized positioning result file.

[0219] It adopts a dual output mode of "platform display + terminal push": on the one hand, the geographical coordinates of the fault point (overlaid on the electronic map of the line) and related location information are displayed on the industrial monitoring platform, so that the monitoring personnel can keep track of the situation in real time; on the other hand, the location results are pushed to the mobile terminal of the operation and maintenance personnel through the wireless communication network, along with auxiliary information such as surrounding landmarks and traffic routes, which greatly improves the efficiency of fault handling.

[0220] The embodiments of the present invention achieve intelligent and precise fault location of power distribution lines through a complete technical chain of basic construction, data acquisition, feature processing, branch filtering, distance calculation and result output.

[0221] Compared to traditional positioning methods, its core advantage lies in:

[0222] First, by relying on a dynamically updated topology impedance library, the positioning deviation caused by static line information is resolved, ensuring the reliability of the positioning base data.

[0223] Secondly, the combination of multi-terminal collaborative data collection and multi-dimensional feature extraction effectively avoids the limitations of single-terminal data collection and signal noise interference, and improves the accuracy of fault feature identification.

[0224] Third, the progressive fault branch screening mechanism accurately eliminates non-faulty branches and false reflection wave interference, significantly reducing the false location rate.

[0225] Fourth, through propagation path optimization and impedance matching correction, accurate calculation of fault distance and accurate mapping of geographical coordinates were achieved, providing precise guidance for operation and maintenance work.

[0226] Fifth, the closed-loop design of the entire process covers all key links from data acquisition to result output, which significantly improves the response speed and operational stability of fault location, effectively shortens the fault handling time, reduces operation and maintenance costs, and ensures the safe and reliable operation of power distribution lines.

[0227] Optionally, refer to Figure 2 , Figure 2 This is a schematic diagram of the structure of the power distribution line fault accurate location system provided by the present invention. The power distribution line fault accurate location system includes...

[0228] The topology impedance library module 210 is used to construct a distribution line topology impedance library, sort out the topology structure of the main feeder and branch lines, collect line parameters and deploy transient signal acquisition terminals, and record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals before entering them into the distribution line topology impedance library.

[0229] The multi-terminal acquisition module 220 is used to trigger an alarm when any transient signal acquisition terminal detects a fault traveling wave signal after the power distribution line topology impedance library is constructed, and synchronize it to other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0230] The signal processing and extraction module 230 is used to preprocess the verified traveling wave signal and extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0231] The fault branch screening module 240 is used to combine the information of the power distribution line topology impedance library with the extracted parameters, and to screen for fault-related branches by time difference, impedance deviation and signal polarity.

[0232] The path tracing initial calculation module 250 is used to trace the traveling wave path of the fault-related branch and construct a simplified propagation path from the head to the fault point to the end, calculate the actual propagation speed of the traveling wave, and initially determine the fault distance by combining the feature point timestamps.

[0233] The distance correction output module 260 is used to correct the fault distance based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, convert it into geographic coordinates, and output the location result.

[0234] This invention addresses the pain points of traditional positioning methods—namely, by constructing a dynamically updated topological impedance library, employing a multi-terminal collaborative acquisition and synchronous verification mechanism, implementing multi-dimensional feature extraction and progressive fault branch screening, and combining path optimization and wave impedance adaptation correction strategies. This not only fundamentally solves the problems of static line information, limitations of single-terminal acquisition, branch reflection interference, and the impact of wave impedance abrupt changes that lead to high positioning deviations and false positioning rates, but also ensures the reliability of basic positioning data, the high quality of raw data, and the accuracy of fault feature identification. Furthermore, it achieves intelligent full-process management from initial distance calculation to precise mapping of geographical coordinates of fault points, significantly improving the response speed, accuracy, and operational stability of fault location. Ultimately, it provides maintenance personnel with intuitive and accurate fault location guidance, effectively shortening fault handling time, reducing maintenance costs, and ensuring the safe and reliable operation of power distribution lines.

[0235] Please see Figure 3 , Figure 3 An embodiment diagram of an electronic device provided in accordance with the present invention. For example... Figure 3As shown, an embodiment of the present invention provides an electronic device 300, including a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor 320. When the processor 320 executes the computer program 311, it performs the following steps:

[0236] Construct a distribution line topology impedance database, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals and then enter them into the distribution line topology impedance database;

[0237] After the distribution line topology impedance library is constructed, when any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0238] The traveling wave signal that passes the verification is preprocessed to extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0239] By combining the information from the power distribution line topology impedance library and the extracted parameters, the fault-related branches are determined through filtering based on time difference, impedance deviation, and signal polarity.

[0240] Tracing the traveling wave path of the fault-related branch and constructing a simplified propagation path from the head to the fault point to the end, calculating the actual propagation speed of the traveling wave, and initially determining the fault distance by combining the feature point timestamps;

[0241] Based on the impedance distribution characteristics of fault-related branches in the power distribution line topology impedance library, the fault distance is corrected, converted into geographic coordinates, and the location result is output.

[0242] Please see Figure 4 , Figure 4 An embodiment diagram of a computer-readable storage medium provided in accordance with an embodiment of the present invention is shown. Figure 4 As shown, this embodiment provides a computer-readable storage medium 400 on which a computer program 311 is stored. When the computer program 311 is executed by a processor, it performs the following steps:

[0243] Construct a distribution line topology impedance database, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals and then enter them into the distribution line topology impedance database;

[0244] After the distribution line topology impedance library is constructed, when any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification.

[0245] The traveling wave signal that passes the verification is preprocessed to extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter.

[0246] By combining the information from the power distribution line topology impedance library and the extracted parameters, the fault-related branches are determined through filtering based on time difference, impedance deviation, and signal polarity.

[0247] Tracing the traveling wave path of the fault-related branch and constructing a simplified propagation path from the head to the fault point to the end, calculating the actual propagation speed of the traveling wave, and initially determining the fault distance by combining the feature point timestamps;

[0248] Based on the impedance distribution characteristics of fault-related branches in the power distribution line topology impedance library, the fault distance is corrected, converted into geographic coordinates, and the location result is output.

[0249] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0250] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0251] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for accurately locating a fault on a power distribution line, the method comprising: Includes the following steps: ​ Construct a distribution line topology impedance database, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, and record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals before entering them into the distribution line topology impedance database; After the distribution line topology impedance library is constructed, when any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification. The traveling wave signal that passes the verification is preprocessed to extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter. By combining the information from the power distribution line topology impedance library with the extracted parameters, the fault-related branches are determined through filtering based on time difference, impedance deviation, and signal polarity. Tracing the traveling wave path of the fault-related branch and constructing a simplified propagation path from the head to the fault point to the end, calculating the actual propagation speed of the traveling wave, and initially determining the fault distance by combining the feature point timestamps; Based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, the fault distance is corrected, converted into geographic coordinates, and the location result is output. The step of determining the fault-related branch by combining the information from the power distribution line topology impedance library with the extracted parameters and filtering by time difference, impedance deviation, and signal polarity includes: A preliminary screening of time differences is performed. Based on the parameters of the distribution line topology impedance library, the theoretical propagation time range of traveling waves is calculated, and branch lines whose traveling wave leading edge time difference exceeds the range are eliminated. A secondary screening of impedance deviations is performed, based on the voltage-current amplitude ratio, to retain candidate fault branches with deviations within a preset range; The final screening of signal polarity is carried out, and the branch lines with opposite signal polarities at the first and last transient signal acquisition terminals are selected and identified as fault-related branches. The preliminary time difference screening includes: Based on the parameters of the aforementioned distribution line topology impedance library, using the formula... The theoretical propagation time range is calculated, where, This indicates the propagation time range of traveling wave theory. This indicates the deviation value of the line segment length. This represents the reference value for the propagation speed of traveling waves; Compare the actual time difference of the traveling wave leading edge with the theoretical propagation time range; Remove branch lines that exceed the theoretical propagation time range; The final signal polarity screening includes: Extract the signal waveforms from the transient signal acquisition terminal at the beginning and end of the candidate fault branch; Determine the zero-phase point of the waveform, and use the zero-phase point as a reference to determine the signal polarity; Filter out branches with opposite signal polarities; The steps of tracing the traveling wave path of the fault-related branch and constructing a simplified propagation path from the head to the fault point to the end, calculating the actual propagation speed of the traveling wave, and initially determining the fault distance by combining the feature point timestamps include: Based on the topological information of the fault-related branches, the propagation path of the traveling wave is traced; Construct a simplified propagation path from the beginning to the point of failure to the end; Calculate the actual propagation speed of the traveling wave; Extract the timestamps of all transient signal acquisition terminals that detected fault signals, and determine the earliest timestamp as the fault trigger time; The initial distance to the fault point is calculated by combining the traveling wave leading edge time of the transient signal acquisition terminal at the first end; The step of correcting the fault distance based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance database, converting it into geographic coordinates, and outputting the location result includes: Extract the wave impedance data of the fault-related branch; Determine the impedance continuity of the corresponding line segment based on the wave impedance data; The fault distance is corrected based on impedance continuity; Retrieve the installation coordinates of the transient signal acquisition terminal and convert the corrected fault distance into geographical coordinates; The output includes the fault branch name, distance to the fault point, and geographic coordinates.

2. The method for accurate fault location in power distribution lines according to claim 1, characterized in that, The steps for constructing the distribution line topology impedance library include: Based on the design drawings and on-site measurement data, the topology of the power distribution line was sorted out, and the location of branch nodes, line length, conductor type and joint distribution information were clarified. Collect line parameters, which specifically include the measured wave impedance values ​​and the reference values ​​of traveling wave propagation speed for each line segment; Divide the fault monitoring zones and deploy transient signal acquisition terminals with built-in time synchronization modules in each zone; Record the unique identifier, installation coordinates, and topology information of the transient signal acquisition terminal, input them into the power distribution line topology impedance database, and update the database in real time.

3. The method for accurate fault location in power distribution lines according to claim 1, characterized in that, When any transient signal acquisition terminal detects a fault traveling wave signal, it triggers an alarm and synchronizes with other transient signal acquisition terminals in the same fault monitoring zone. The steps for each transient signal acquisition terminal to collaboratively acquire voltage and current transient traveling wave signals and corresponding timestamps and then upload them to the positioning host for data integrity verification include: Preset fault traveling wave trigger threshold; When the signal amplitude detected by the transient signal acquisition terminal exceeds the fault traveling wave trigger threshold, an alarm is immediately triggered, and the alarm information is synchronized to other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and their corresponding timestamps; The collected data is uploaded to the positioning host, which verifies the integrity of the data and removes missing data.

4. The method for accurate fault location in power distribution lines according to claim 1, characterized in that, The steps of preprocessing the verified traveling wave signal and extracting the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter include: The traveling wave signal that has passed the verification of the positioning host is filtered to remove high and low frequency interference; Wavelet transform decomposition is performed on the filtered signal to extract the detail components of the core frequency band of the fault transient traveling wave; Identify the characteristic points of the traveling wave leading edge and record the timestamp, while ensuring that the timestamp is consistent with the time synchronization module of the transient signal acquisition terminal; Calculate the ratio of voltage to current amplitude. This ratio directly reflects the impedance matching status of the line segment and serves as the core parameter for subsequent branch selection.

5. The method for accurate fault location in power distribution lines according to claim 4, characterized in that, The steps for calculating the voltage-current amplitude ratio include: Accurately record the timestamps of characteristic points at the leading edge of the traveling wave to ensure that the timestamps are accurately synchronized with the time synchronization module of the transient signal acquisition terminal; Calculate the voltage-to-current amplitude ratio and use this ratio as the core screening parameter; By analyzing the numerical deviation of the voltage-current amplitude ratio, the degree of abnormality in the impedance matching state of the corresponding line segment can be determined.

6. A precise fault location system for power distribution lines, characterized in that, The system, applied to the precise fault location method for power distribution lines as described in any one of claims 1 to 5, comprises: The topology impedance library module is used to construct a distribution line topology impedance library, sort out the topology structure of main feeders and branch lines, collect line parameters and deploy transient signal acquisition terminals, and record the unique identifier, installation coordinates and topology attribution information of the transient signal acquisition terminals before entering them into the distribution line topology impedance library. The multi-terminal acquisition module is used to trigger an alarm when any transient signal acquisition terminal detects a fault traveling wave signal after the power distribution line topology impedance library is constructed, and synchronize it to other transient signal acquisition terminals in the same fault monitoring zone. Each transient signal acquisition terminal collaboratively acquires voltage and current transient traveling wave signals and corresponding timestamps, and then uploads them to the positioning host for data integrity verification. The signal processing and extraction module is used to preprocess the verified traveling wave signal and extract the timestamps of the feature points of the traveling wave leading edge and the voltage-current amplitude ratio parameter. The fault branch filtering module is used to combine the information from the power distribution line topology impedance library with the extracted parameters, and to determine the fault-related branches by filtering based on time difference, impedance deviation and signal polarity. The path tracing initial calculation module is used to trace the traveling wave path of the fault-related branch and construct a simplified propagation path from the head to the fault point to the end, calculate the actual propagation speed of the traveling wave, and initially determine the fault distance by combining the feature point timestamps. The distance correction output module is used to correct the fault distance based on the impedance distribution characteristics of the fault-related branches in the power distribution line topology impedance library, convert it into geographic coordinates, and output the location result.

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