Anti-interference fault location method and device

Abstract

The invention relates to the technical field of cable distance measurement, and discloses an anti-interference fault distance measurement method and device, and the method comprises the steps: collecting a transient voltage traveling wave signal generated when a fault occurs in a cable, and obtaining the original traveling wave data of the cable; performing adaptive filtering on the original traveling wave data to obtain enhanced traveling wave data of the cable; extracting wave head features from the enhanced traveling wave data; multi-channel wave head time fusion is carried out on points with first-order derivatives exceeding a preset threshold value in the wave head features, and the traveling wave arrival time of the cable is obtained; determining fault location of the cable based on the traveling wave arrival time, and performing density clustering fusion on a plurality of fault location results to obtain an accurate fault point position of the cable; performing wave velocity compensation on the accurate fault point position, and restoring the actual distance of the fault point in the cable to obtain a diagnosis result of the fault point; according to the invention, the efficiency of anti-interference fault distance measurement can be improved.

Description

Technical Field

[0001] This invention relates to the field of cable ranging technology, and in particular to an interference-resistant fault ranging method and apparatus. Background Technology

[0002] Existing technologies have significant shortcomings in the data acquisition and preprocessing stages of cable fault location. They do not employ multi-channel synchronous acquisition and common-mode suppression techniques to process transient voltage traveling wave signals, but instead acquire raw data through a single channel. This makes them susceptible to external electromagnetic interference and signal attenuation, resulting in low signal-to-noise ratios and waveform distortion in the acquired raw traveling wave data. Furthermore, the filtering process does not dynamically adjust filter parameters based on interference distribution information, but instead uses a single filtering method with fixed parameters. This fails to eliminate different types of interference and effectively preserves the true characteristics of the traveling wave signal. The processed signal still contains a large number of interference components, resulting in low-quality basic data for subsequent wavefront feature extraction and fault location, directly affecting the accuracy of the distance measurement.

[0003] Existing technologies have significant shortcomings in fault location and result optimization. Wavefront feature extraction fails to accurately identify abrupt feature changes through differential processing and threshold standards, relying solely on visual observation or simple threshold judgment. This easily leads to misclassification of spurious wavefronts generated by interference as valid features, resulting in inaccurate travel wave arrival time calculations. Furthermore, fault location does not consider the wave velocity differences between overhead and cable line sections, using only a uniform wave velocity to calculate the fault location. The lack of density clustering fusion of multiple location results fails to offset random and systematic errors, resulting in high dispersion of location results. Additionally, the absence of a segmented compensation mechanism for line type and wave velocity differences, relying only on simple wave velocity correction, is insufficient to compensate for distance deviations caused by wave velocity variations in different line sections. Ultimately, the fault ranging results are inaccurate and cannot meet the requirements for rapid and accurate cable fault location. Summary of the Invention

[0004] This invention provides an interference-resistant fault location method and apparatus to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides an interference-resistant fault location method, comprising: S1. Acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and obtain the original traveling wave data of the cable; S2. Adaptive filtering is performed on the original traveling wave data to obtain the enhanced traveling wave data of the cable; S3. Extract wavefront features from the enhanced traveling wave data; S4. Perform multi-channel wavefront time fusion on the points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. S5. Based on the arrival time of the traveling wave, determine the fault location of the cable, and perform density clustering fusion on the results of multiple fault locations to obtain the precise fault location of the cable. S6. Perform wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

[0006] In a preferred embodiment, the acquisition of the transient voltage traveling wave signal generated by the acquisition cable when a fault occurs, to obtain the raw traveling wave data of the cable, includes: The voltage signals of the three phase conductors of the cable are simultaneously acquired by a multi-channel synchronous acquisition device to obtain the raw three-phase voltage data of the cable. The original three-phase voltage data is amplified and common-mode suppressed to obtain the conditioned voltage signal of the cable. The conditioned voltage signal is converted from analog to digital to obtain digitized transient voltage waveform data; The digitized transient voltage waveform data is timestamped to obtain the original traveling wave data of the cable.

[0007] In a preferred embodiment, the step of adaptively filtering the original traveling wave data to obtain the enhanced traveling wave data of the cable includes: The interference component characteristics in the original traveling wave data are identified to obtain the interference distribution information of the cable; Based on the interference distribution information, the corresponding filter parameters are configured to obtain an optimized filter configuration; The original traveling wave data is filtered in multiple stages using the optimized filter configuration to obtain the preliminary processed signal data of the cable. The quality of the pre-processed signal data is evaluated, and the filter parameters are adjusted based on the evaluation results to obtain enhanced traveling wave data that meets the quality requirements.

[0008] In a preferred embodiment, the step of performing a quality assessment on the pre-processed signal data and adjusting the filter parameters based on the quality assessment result includes: Feature extraction is performed on the pre-processed signal data to obtain quality assessment indicators of signal-to-noise ratio and waveform integrity in the original traveling wave data; The quality assessment indicators are compared and analyzed with the preset quality standards to obtain the quality deviation information of the preliminary processed signal data; Based on the quality deviation information, a parameter adjustment scheme is generated for the notch filter bandwidth and the number of wavelet decomposition layers. Based on the parameter adjustment scheme, the configuration parameters of the filter are updated to obtain the optimized filter configuration.

[0009] In a preferred embodiment, extracting wavefront features from the enhanced traveling wave data includes: The enhanced traveling wave data is differentiated to obtain the signal rate of change derivative sequence of the cable; Based on the statistical characteristics of the derivative sequence of the signal rate of change, a threshold standard for the cable is established; Based on the threshold criteria, identify the characteristic abrupt change points in the derivative sequence of the signal rate of change; The true and valid feature mutation points are output as the wavefront characteristics of the cable.

[0010] In a preferred embodiment, the step of performing multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable includes: The initial wavefront time series of the cable is obtained by collecting wavefront features identified by multiple detection channels; Time-align the initial wavefront time series to the wavefront time dataset of the cable; Based on the wavefront time difference values ​​of each channel in the wavefront time dataset, valid time points that meet the consistency requirements are selected. The effective time points are weighted and fused to obtain the traveling wave arrival time of the cable.

[0011] In a preferred embodiment, determining the fault location of the cable based on the traveling wave arrival time, and performing density clustering fusion on multiple fault location results to obtain the precise fault location of the cable, includes: Based on the cable's line topology, determine the complete transmission path between the two terminals in the cable; Distinguish between overhead line segments and cable line segments in the complete transmission path; The fault location of the cable is determined based on the arrival time of the traveling wave and the wave velocity difference between the overhead line segment and the cable line segment.

[0012] In a preferred embodiment, the step of performing density clustering fusion on the results of multiple fault locations to obtain the precise fault location of the cable includes: Based on the spatial distribution characteristics of multiple fault locations, a fault spatial distribution model of the cable is constructed; In the fault spatial distribution model, spatially adjacent location points are divided into the same cluster region; Filter out the effective cluster regions containing the most location points; The precise location of the cable fault point is obtained based on the geometric center of all positioning points in the effective clustering region.

[0013] In a preferred embodiment, the step of performing wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, in order to obtain the diagnostic result of the fault point, includes: Based on the characteristics of the mixed sections of the cable, a segmented compensation mapping relationship between line type distribution and wave velocity difference is established; Based on the segmented compensation mapping relationship, segmented wave velocity compensation is performed on the precise fault location to obtain the preliminary compensation result of the cable. Based on the multi-dimensional verification results of the preliminary compensation results, the preliminary compensation results are dynamically adjusted to obtain the optimized actual distance of the fault point; By combining the optimized actual distance to the fault point, line log data, and operating parameters, a diagnostic result for the fault point in the cable is generated.

[0014] To address the above problems, the present invention also provides an interference-resistant fault location device, the device comprising: The data acquisition module is used to acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and to obtain the original traveling wave data of the cable. A data filtering module is used to adaptively filter the original traveling wave data to obtain the enhanced traveling wave data of the cable. The feature extraction module is used to extract wavefront features from the enhanced traveling wave data; The traveling wave arrival time calculation module is used to perform multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. The fault location module is used to determine the fault location of the cable based on the arrival time of the traveling wave, and to perform density clustering fusion on the results of multiple fault locations to obtain the precise location of the fault point of the cable. The positioning compensation module is used to perform wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention significantly improves the quality and anti-interference capability of fault location baseline data through refined data acquisition and adaptive filtering. A multi-channel synchronous acquisition device is used to acquire the voltage signals of the three-phase conductors of the cable. After signal amplification, common-mode rejection, and analog-to-digital conversion, original traveling wave data with timestamps is generated, ensuring the integrity and synchronization of data acquisition. By identifying the interference distribution information in the original traveling wave data, filter parameters are dynamically configured and multi-level filtering is performed. The filter configuration is optimized based on the quality assessment results of signal-to-noise ratio and waveform integrity, generating enhanced traveling wave data that meets quality requirements. This effectively eliminates various interference components, providing highly reliable signal support for subsequent fault location.

[0016] 2. This invention significantly improves the accuracy and reliability of fault location by employing precise feature extraction, localization fusion, and wave velocity compensation mechanisms. Enhanced traveling wave data is differentially processed to obtain the signal rate of change derivative sequence. A threshold standard is established based on statistical characteristics to identify the true wavefront features. Then, through multi-channel wavefront time alignment, effective time point filtering, and weighted fusion, the arrival time of the traveling wave is accurately determined. Combining line topology to distinguish between overhead and cable sections, the fault is initially located based on the difference in traveling wave arrival time and wave velocity. Density clustering is used to fuse multiple localization results to obtain the precise fault location. A segmented compensation mapping relationship is established based on the characteristics of mixed sections, dynamically adjusting and optimizing the precise fault location. Combined with line records and operating parameters, diagnostic results are generated, comprehensively ensuring the accuracy and practicality of fault location. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating an anti-interference fault location method according to an embodiment of the present invention. Figure 2 A functional block diagram of an anti-interference fault location device provided in an embodiment of the present invention; The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] This application provides an interference-resistant fault location method. The execution subject of this interference-resistant fault location method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the interference-resistant fault location method can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDNs), and big data and artificial intelligence platforms.

[0020] Reference Figure 1 The diagram shown is a flowchart illustrating an anti-interference fault location method according to an embodiment of the present invention. In this embodiment, the anti-interference fault location method includes: S1. Acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and obtain the original traveling wave data of the cable; In this embodiment of the invention, the acquisition of the transient voltage traveling wave signal generated by the acquisition cable when a fault occurs, and the obtaining of the original traveling wave data of the cable, includes: The voltage signals of the three phase conductors of the cable are simultaneously acquired by a multi-channel synchronous acquisition device to obtain the raw three-phase voltage data of the cable. The original three-phase voltage data is amplified and common-mode suppressed to obtain the conditioned voltage signal of the cable. The conditioned voltage signal is converted from analog to digital to obtain digitized transient voltage waveform data; The digitized transient voltage waveform data is timestamped to obtain the original traveling wave data of the cable.

[0021] Specifically, when acquiring the raw three-phase voltage data of the cable by simultaneously acquiring the voltage signals of the three-phase conductors of the cable using a multi-channel synchronous acquisition device, the three acquisition channels of the multi-channel synchronous acquisition device are connected to the corresponding three-phase conductors of the cable, ensuring that the connection between each channel and the conductor is stable and has good contact. The synchronous trigger function of the acquisition device is activated, causing the three channels to start acquiring voltage signals at the same time. During the acquisition process, the sampling frequency and sampling duration of each channel are kept completely consistent to avoid data deviations caused by asynchronous acquisition. The voltage signals acquired by each channel are received and stored in real time, forming independent voltage data sets corresponding to the three-phase conductors. These sets together constitute the raw three-phase voltage data of the cable.

[0022] Furthermore, to obtain the conditioned voltage signal of the cable, the three-phase raw voltage data undergoes signal amplification and common-mode rejection. The three-phase raw voltage data are then input to the amplification unit of the signal conditioning module. The amplification unit increases the signal strength by a fixed ratio based on the actual amplitude of the voltage signal, bringing the weak voltage signal to the standard amplitude required for subsequent processing. Simultaneously, the common-mode rejection unit of the signal conditioning module processes the voltage signal of each channel, identifying and filtering out common interference signals in the three-phase signals, retaining the effective voltage signal related to the cable fault. After amplification and common-mode rejection, a voltage signal with stable amplitude and low interference is output; this signal is the conditioned voltage signal of the cable.

[0023] Furthermore, when performing analog-to-digital conversion on the conditioned voltage signal to obtain digitized transient voltage waveform data, the conditioned voltage signal is input into the analog-to-digital conversion module. The sampling circuit inside the module continuously samples the analog conditioned voltage signal at preset sampling intervals, capturing the voltage amplitude at each sampling moment. The voltage amplitude at each sampling moment is converted into a corresponding digital code, and the encoding rules follow a fixed conversion standard to ensure that the digital code accurately reflects the magnitude of the voltage amplitude. All digital codes are arranged in chronological order of sampling time to form a digital sequence that can completely characterize the changes in the transient voltage waveform; this sequence is the digitized transient voltage waveform data.

[0024] Furthermore, when the digitized transient voltage waveform data is timestamped to obtain the original traveling wave data of the cable, the system time recorded at each sampling moment during the analog-to-digital conversion process is retrieved. The system time is accurate enough to distinguish the subtle changes in the transient voltage traveling wave signal.

[0025] In detail, the system time at each sampling moment is used as a timestamp and associated one-to-one with the corresponding digital code in the digitized transient voltage waveform data, ensuring that each digital code is accompanied by a unique time identifier. All digital codes associated with timestamps are organized in chronological order to form a complete data set containing time information and digitized voltage amplitude information. This set is the original traveling wave data of the cable.

[0026] In summary, by simultaneously acquiring the voltage signals of the three-phase conductors of a cable using a multi-channel synchronous acquisition device, raw three-phase voltage data is obtained. Each of the three acquisition channels corresponds precisely to one of the three phase conductors, and the acquisition actions are triggered synchronously, ensuring that the sampling frequency and duration of each channel are completely consistent. This acquisition method avoids the limitations of single-channel acquisition, comprehensively captures the transient voltage traveling wave signals of the three-phase conductors, and eliminates data deviations caused by asynchronous acquisition, providing complete and synchronized raw voltage data support for subsequent analysis.

[0027] In summary, the three-phase raw voltage data undergoes signal amplification and common-mode rejection to obtain a conditioned voltage signal. Amplification increases the amplitude of weak voltage signals by a fixed ratio to meet the standards required for subsequent processing. Common-mode rejection accurately identifies and filters out unwanted signals such as electromagnetic interference present in the three-phase signals, retaining valid signals related to the fault. The combination of these two methods effectively improves the signal-to-noise ratio of the raw signal, reduces the impact of interference on the data, and outputs a conditioned voltage signal with stable amplitude and low interference.

[0028] In summary, the conditioned voltage signal undergoes analog-to-digital conversion to obtain digitized transient voltage waveform data. A sampling circuit captures the voltage amplitude of the analog signal at preset intervals and converts it into a standardized digital code. This digital processing makes the signal easier to store, transmit, and analyze, avoiding the problems of analog signals being susceptible to environmental influences and distortion. Furthermore, the time-sequential digital code can completely characterize transient voltage waveform changes, laying the foundation for subsequent timestamping and fault feature extraction.

[0029] In summary, the original traveling wave data is obtained by timestamping the digitized transient voltage waveform data. The system time of each sampling moment is bound to the corresponding digital code, so that each data point is accompanied by a unique time identifier. The timestamp clearly records the time evolution process of the transient voltage traveling wave signal, which facilitates subsequent analysis of key information such as the propagation time and wavefront arrival time of the traveling wave. This ensures the accuracy and traceability of time-series data in the fault location process, providing key time dimension support for accurate fault location, which is in line with the invention's core objective of "improving the efficiency of anti-interference fault location".

[0030] S2. Adaptive filtering is performed on the original traveling wave data to obtain the enhanced traveling wave data of the cable; In this embodiment of the invention, the step of adaptively filtering the original traveling wave data to obtain the enhanced traveling wave data of the cable includes: The interference component characteristics in the original traveling wave data are identified to obtain the interference distribution information of the cable; Based on the interference distribution information, the corresponding filter parameters are configured to obtain an optimized filter configuration; The original traveling wave data is filtered in multiple stages using the optimized filter configuration to obtain the preliminary processed signal data of the cable. The quality of the pre-processed signal data is evaluated, and the filter parameters are adjusted based on the evaluation results to obtain enhanced traveling wave data that meets the quality requirements.

[0031] The step of performing a quality assessment on the pre-processed signal data and adjusting the filter parameters based on the quality assessment results includes: Feature extraction is performed on the pre-processed signal data to obtain quality assessment indicators of signal-to-noise ratio and waveform integrity in the original traveling wave data; The quality assessment indicators are compared and analyzed with the preset quality standards to obtain the quality deviation information of the preliminary processed signal data; Based on the quality deviation information, a parameter adjustment scheme is generated for the notch filter bandwidth and the number of wavelet decomposition layers. Based on the parameter adjustment scheme, the configuration parameters of the filter are updated to obtain the optimized filter configuration.

[0032] Specifically, when identifying the characteristics of interference components in the original traveling wave data to obtain the interference distribution information of the cable, a comprehensive analysis of the voltage amplitude variation over time in the original traveling wave data is conducted to distinguish the changing trend of normal transient voltage traveling waves from abnormal fluctuations. By comparing the typical characteristics of the traveling wave signal of the faulty cable, interference components in the original data that do not conform to the typical characteristics are located, and key characteristics such as the occurrence time, duration, amplitude range, and frequency of change of the interference components are clarified. The characteristic information of these interference components is classified and organized according to time sequence and characteristic type to form an information set that clearly reflects the distribution of interference in the original data. This set is the interference distribution information of the cable.

[0033] Furthermore, based on the interference distribution information, corresponding filter parameters are configured to obtain an optimized filter. The amplitude filtering threshold of the filter is set according to the amplitude range of the interference components in the interference distribution information to ensure accurate interception of interference signals within this range. The frequency response characteristics of the filter are adjusted according to the changing frequency of the interference components, so that the filter exhibits high attenuation characteristics for signals at interference frequencies while maintaining low attenuation for normal traveling wave signals. The filter's filtering strength and response speed are set based on the duration and occurrence pattern of the interference components to ensure that the filter can quickly respond to the appearance of interference signals and continuously perform its filtering function. These configured parameters are then imported into the basic filter model to form an optimized filter adapted to the current interference distribution.

[0034] Furthermore, the original traveling wave data is subjected to multi-stage filtering using an optimized filter configuration to obtain the preliminary processed signal data for the cable. The original traveling wave data is input into the optimized filter configuration. The first-stage filter focuses on filtering strong interference signals with amplitudes exceeding a set threshold, retaining data components within the normal traveling wave amplitude range. After the first-stage filtering, the output data is fed into the second-stage filtering stage. This stage precisely filters specific frequency interference in the interference distribution information, further eliminating signal components matching the interference frequency. Subsequent filtering stages sequentially focus on different types of interference characteristics, progressively refining the filtering process. Each filtering stage is based on the output results of the previous stage, performing targeted processing to ensure the gradual removal of various interference components from the original data. After multiple stages of continuous filtering, the output signal data retains the core characteristics of a normal transient voltage traveling wave; this data is the preliminary processed signal data for the cable.

[0035] Furthermore, a quality assessment is performed on the pre-processed signal data. Based on the assessment results, filter parameters are adjusted to obtain enhanced traveling wave data that meets quality requirements. Signal quality assessment standards are established, including key assessment dimensions such as the degree of preservation of normal traveling wave characteristics, the residual proportion of interference signals, and the stability of signal amplitude. The performance of the pre-processed signal data in each dimension is checked against the assessment standards to determine whether the data meets the quality requirements for subsequent fault location analysis. If the assessment results show that residual interference or loss of normal traveling wave characteristics still exists in the data, the filter's amplitude threshold, frequency response characteristics, or filter strength are adjusted in reverse based on the characteristics of the residual interference or the lost traveling wave characteristics.

[0036] In detail, the adjusted parameters are re-imported into the filter, and the original traveling wave data is filtered again through multiple stages. The quality assessment and parameter adjustment process is repeated until the output signal data meets the quality requirements in all assessment dimensions. This final signal data is the enhanced traveling wave data of the cable.

[0037] Specifically, when extracting features from the pre-processed signal data to obtain quality assessment indicators for signal-to-noise ratio (SNR) and waveform integrity in the original traveling wave data, the effective traveling wave signal component and residual interference component in the pre-processed signal data are first separated. By comparing the amplitude energy ratios of the two, the strength relationship between the effective signal and the interference signal is determined, thereby obtaining the SNR indicator. Simultaneously, referring to the typical waveform characteristics of fault transient voltage traveling waves, including wavefront shape, amplitude variation trend, and duration, the waveform of the pre-processed signal data is compared one by one with the typical characteristics to check for missing wavefronts, waveform distortion, or loss of key feature points. Based on this, the waveform integrity indicator is quantified.

[0038] Furthermore, by comparing and analyzing the quality assessment indicators with preset quality standards, the quality deviation information of the initially processed signal data is obtained. The preset quality standards include a minimum acceptable threshold for signal-to-noise ratio (SNR) and a minimum acceptable requirement for waveform integrity. These standards are based on the requirements of traveling wave signals for cable fault location. The extracted SNR indicator is compared with the preset threshold to determine whether it meets the acceptable standard; if not, the extent of the SNR deficiency is identified. The waveform integrity indicator is compared with the preset requirements to identify missing features or distortion locations in the waveform. The comparison results of SNR and waveform integrity are integrated, and the differences between the indicators and standards are recorded in detail to form quality deviation information including deviation type, degree, and location.

[0039] Furthermore, when generating parameter adjustment schemes for the notch filter bandwidth and wavelet decomposition level based on the quality deviation information, if the quality deviation information shows that there is residual interference at a specific frequency that causes insufficient signal-to-noise ratio, the frequency range of the residual interference is analyzed, and the bandwidth of the notch filter is adjusted accordingly so that the bandwidth just covers the interference frequency range, ensuring that the interference at that frequency can be accurately filtered, while avoiding affecting the normal frequency components of the effective traveling wave signal.

[0040] In detail, if the deviation information indicates insufficient waveform integrity, waveform distortion, or loss of key features, the number of wavelet decomposition layers is adjusted according to the severity of the distortion and the extent of feature loss. If the distortion is slight, the number of decomposition layers is appropriately reduced to retain more original waveform information. If the distortion is severe, the number of decomposition layers is increased to more precisely separate the effective signal from the interference, thus forming a clear scheme for parameter adjustment direction and specific adjustment content.

[0041] Furthermore, based on the parameter adjustment scheme, the filter configuration parameters are updated to obtain the optimized filter configuration. According to the notch filter bandwidth adjustment value determined in the parameter adjustment scheme, the bandwidth parameters of the notch module in the original filter are modified to ensure that the new bandwidth parameters accurately match the frequency range of residual interference. Based on the wavelet decomposition level adjustment value set in the scheme, the level parameters of the wavelet decomposition module in the filter are updated to match the decomposition level with the waveform integrity restoration requirements. During the parameter update process, the collaborative working logic of each filter module is simultaneously calibrated to ensure that the adjusted bandwidth parameters and decomposition level parameters can cooperate with each other, avoiding parameter conflicts that could affect the filtering effect. After the parameter update is completed, a new filter configuration file is generated, which is the optimized filter configuration.

[0042] In summary, identifying the characteristics of interference components in the raw traveling wave data yields interference distribution information. By comprehensively analyzing abnormal fluctuations in voltage amplitude in the raw data, normal transient traveling waves are distinguished from interference signals, clarifying key characteristics such as the occurrence time, duration, amplitude range, and frequency of change of the interference. This targeted identification avoids blindly processing interference, enabling subsequent filtering operations to focus on specific interference types. It provides a precise and targeted basis for filter parameter configuration, solving the problem of non-targeted filtering in existing technologies due to the inability to locate interference characteristics.

[0043] In summary, the optimized filter configuration is obtained by configuring filter parameters based on interference distribution information. The filtering threshold is set according to the amplitude range of the interference, the frequency response characteristics are adjusted based on the interference frequency, and the filtering strength and response speed are set in conjunction with the interference persistence pattern. This dynamic configuration method allows the filter to be highly adapted to the interference characteristics in the current raw data, avoiding the shortcomings of fixed-parameter filters in handling different types of interference. It ensures that the filter can specifically eliminate various types of interference while preserving the core characteristics of the normal traveling wave signal.

[0044] In summary, multi-stage filtering of the raw traveling wave data using optimized filters yields pre-processed signal data. Each stage of filtering sequentially focuses on different interference characteristics—the first stage filters strong amplitude interference, while subsequent stages finely process specific frequencies or residual interference. Through this progressive filtering process, interference components in the raw data are gradually removed. Compared to existing single-filtering methods, multi-stage filtering can more thoroughly eliminate complex interference while minimizing damage to the normal traveling wave signal, resulting in pre-processed signal data with high purity. This lays a solid foundation for subsequent quality assessment and parameter adjustment.

[0045] In summary, the process involves evaluating the quality of the initially processed signal data and adjusting filter parameters accordingly. Signal quality is assessed using metrics such as signal-to-noise ratio and waveform integrity. If residual interference or loss of traveling wave characteristics is found, the filter parameters are optimized and the signal is re-filtered. This closed-loop mechanism of "filtering-evaluation-adjustment" continuously corrects deviations during the filtering process, ensuring that the final enhanced traveling wave data meets the quality requirements for fault location. This solves the problems of fixed filtering in existing technologies being unable to cope with interference variations and ensuring signal quality. It provides highly reliable signal support for subsequent wavefront feature extraction and accurate fault location, aligning with the invention's core objective of "improving the efficiency and accuracy of anti-interference fault ranging."

[0046] In summary, key quality indicators are extracted to achieve quantitative signal quality assessment: Feature extraction is performed on the pre-processed signal data to separate the effective traveling wave signal from residual interference components. The signal-to-noise ratio (SNR) is obtained by comparing the amplitude-energy ratio of the two components. Simultaneously, the waveform integrity index is obtained by comparing the signal waveform's conformity with the typical waveform characteristics of fault transient voltage traveling waves. This operation transforms abstract signal quality into quantifiable and concrete indicators, avoiding the bias of subjective judgments about signal quality. It provides an objective and accurate basis for subsequent quality assessment, solving the problem of the lack of a unified standard for signal quality assessment in existing technologies.

[0047] In summary, by comparing and analyzing quality assessment indicators such as signal-to-noise ratio (SNR) and waveform integrity against preset quality standards, it is possible to determine whether these indicators meet the acceptable thresholds required for fault location. This allows for the accurate identification of quality deviations such as insufficient SNR, waveform loss, or distortion, while simultaneously recording the type, degree, and location of these deviations to form quality deviation information. This comparison method can quickly locate quality defects in initially processed signal data, providing direction for subsequent parameter adjustments, avoiding blind optimization of filter parameters, and improving the targeted nature of parameter adjustments.

[0048] In summary, this approach generates parameter adjustment schemes for the notch filter bandwidth and wavelet decomposition level based on quality deviation information. For insufficient signal-to-noise ratio caused by residual interference at specific frequencies, the notch filter bandwidth is adjusted to cover the interference frequencies. For waveform integrity defects, the wavelet decomposition level is adjusted according to the degree of distortion. This scheme directly addresses the root cause of quality defects, avoids the randomness of parameter adjustments, and ensures that the adjusted filter can accurately solve signal quality problems and improve filtering performance.

[0049] In summary, by updating the filter configuration parameters based on the parameter adjustment scheme and calibrating the coordination logic between the notch filter bandwidth and the wavelet decomposition level, parameter conflicts are avoided, resulting in an optimized filter configuration. The optimized filter can more accurately eliminate residual interference and repair waveform defects. After re-filtering, it can output enhanced traveling wave data that meets quality requirements, providing highly reliable signal support for subsequent wavefront feature extraction and fault location. This aligns with the invention's core objective of "improving the accuracy and efficiency of anti-interference fault ranging" and solves the problems in existing technologies where fixed filter parameters cannot adapt to dynamic interference and signal quality is difficult to guarantee.

[0050] S3. Extract wavefront features from the enhanced traveling wave data; In this embodiment of the invention, extracting wavefront features from the enhanced traveling wave data includes: The enhanced traveling wave data is differentiated to obtain the signal rate of change derivative sequence of the cable; Based on the statistical characteristics of the derivative sequence of the signal rate of change, a threshold standard for the cable is established; Based on the threshold criteria, identify the characteristic abrupt change points in the derivative sequence of the signal rate of change; The true and valid feature mutation points are output as the wavefront characteristics of the cable.

[0051] Specifically, when differentiating the enhanced traveling wave data to obtain the signal rate of change derivative sequence of the cable, the voltage amplitude at each adjacent time point in the enhanced traveling wave data is calculated to obtain the change in voltage amplitude within each time interval. The voltage change in each time interval is correlated with the corresponding time interval length and converted into a value characterizing the rate of change of the voltage signal through a fixed calculation logic. All the calculated rate of change values ​​are arranged in chronological order to form a sequence of data that continuously reflects the rate of change of the enhanced traveling wave signal; this sequence of data is the signal rate of change derivative sequence of the cable.

[0052] Furthermore, based on the statistical characteristics of the signal rate of change derivative sequence, when establishing the threshold standard for cables, a comprehensive analysis of the distribution of all values ​​in the signal rate of change derivative sequence is conducted to clarify the concentration range, fluctuation amplitude, and frequency of extreme values ​​in the sequence. Typical statistical features in the sequence are extracted, including the concentration interval of most values ​​and the boundaries of abnormal values ​​exceeding normal fluctuations. Based on these statistical features and combined with the typical variation patterns of the traveling wave front of cable fault signals, a boundary value that can distinguish between normal and abrupt changes is set; this boundary value is the threshold standard for cables.

[0053] Furthermore, based on the threshold standard, when identifying characteristic abrupt changes in the derivative sequence of the signal rate of change, each value in the sequence is compared chronologically with the threshold standard. If a value in the sequence exceeds the threshold standard, and all adjacent values ​​are within the threshold standard range, it indicates a significant abrupt change in the signal rate of change at that location. The time points and values ​​corresponding to these values ​​exceeding the threshold standard are recorded and marked as candidate characteristic abrupt changes, thus completing the preliminary identification of characteristic abrupt changes in the derivative sequence of the signal rate of change.

[0054] Furthermore, when outputting the true and valid feature mutation points as the wavefront characteristics of the cable, the marked candidate feature mutation points are verified a second time. By combining the original waveform of the enhanced traveling wave data, it is checked whether there are obvious changes in the wavefront shape of the original voltage signal corresponding to each candidate point. False candidate points caused by minor data fluctuations or residual interference are eliminated, and candidate points that highly match the wavefront characteristics of the original traveling wave signal are retained. The verified true and valid feature mutation points are organized in chronological order, and the timestamp and corresponding voltage amplitude change of each mutation point are clearly defined to form a complete wavefront feature description, which is the wavefront characteristic of the cable.

[0055] In summary, differentiating the enhanced traveling wave data to obtain the derivative sequence of the signal rate of change, and calculating the ratio of the change in voltage amplitude at adjacent time points to the corresponding time interval, transforms the traveling wave data, which originally reflected voltage amplitude, into sequence data characterizing the rate of voltage change. This processing method significantly amplifies the abrupt change characteristics of the wavefront position in the traveling wave signal—the voltage change rate at the wavefront is much higher than in other regions, making the wavefront easier to identify in the derivative sequence. This solves the problem of unclear wavefront features directly from the original amplitude data, providing clear data support for subsequent precise wavefront location.

[0056] In summary, a threshold standard is established based on the statistical characteristics of the derivative sequence of the signal rate of change. By analyzing the concentration range, fluctuation amplitude, and extreme value distribution of values ​​in the sequence, the numerical intervals corresponding to most normal changes are extracted. Combined with the typical variation patterns of the fault traveling wave head, the boundary distinguishing between normal and abrupt changes is determined. This threshold standard is not a fixed value, but a dynamic standard adapted to the characteristics of the current derivative sequence. This avoids the shortcomings of using a fixed threshold, which is easily affected by data fluctuations, ensuring that the wave head identification process is not affected by subjective factors and improving the objectivity and accuracy of the identification results.

[0057] In summary, this method identifies characteristic abrupt changes in the derivative sequence of the signal rate of change based on threshold criteria. Each value in the sequence is compared chronologically with the threshold, and points exceeding the threshold but with values ​​before and after it within the normal range are marked as candidate abrupt changes. This screening method accurately captures significant abrupt changes in the derivative sequence, effectively eliminates false abrupt changes caused by minor data fluctuations, quickly pinpoints the possible location of wavefronts, narrows down the range for subsequent verification of true wavefront characteristics, and improves the efficiency of wavefront identification.

[0058] In summary, the invention outputs the true and valid abrupt change points as the wavefront characteristics of the cable. By combining the original waveform of the enhanced traveling wave data, the candidate abrupt change points are verified a second time—checking whether the original voltage signal corresponding to the candidate point has a typical wavefront shape, and eliminating false candidate points that do not match the original waveform characteristics. The final output wavefront characteristics are based on the abrupt change characteristics of the derivative sequence and closely match the actual shape of the original traveling wave, ensuring the authenticity and effectiveness of the wavefront characteristics. This provides a reliable basis for subsequent multi-channel wavefront time fusion and accurate calculation of the traveling wave arrival time, aligning with the invention's core objective of "improving the accuracy of anti-interference fault location".

[0059] S4. Perform multi-channel wavefront time fusion on the points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. In this embodiment of the invention, the step of performing multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable includes: The initial wavefront time series of the cable is obtained by collecting wavefront features identified by multiple detection channels; Time-align the initial wavefront time series to the wavefront time dataset of the cable; Based on the wavefront time difference values ​​of each channel in the wavefront time dataset, valid time points that meet the consistency requirements are selected. The effective time points are weighted and fused to obtain the traveling wave arrival time of the cable.

[0060] Specifically, when acquiring the wavefront features identified by multiple detection channels to obtain the initial wavefront time series of the cable, the wavefront feature data transmitted by each detection channel is received synchronously to ensure that no channel's detection result is missed. The corresponding timestamp information is extracted from the wavefront features of each channel; this timestamp represents the wavefront arrival time point identified by each channel. The wavefront arrival times of all channels are arranged sequentially according to their channel numbers, forming a continuous sequence containing time information from multiple channels. This sequence constitutes the initial wavefront time series of the cable.

[0061] Furthermore, when aligning the initial wavefront time series to obtain the cable wavefront time dataset, the time reference of the detection channel with the highest stability is used. This reference channel has been verified through historical detection data to have the best timestamp accuracy and stability. The wavefront arrival times of other channels in the initial wavefront time series are compared with the time reference of the reference channel to eliminate time synchronization deviations between different channels. Based on the comparison results, the time points of each channel are uniformly calibrated and adjusted so that the wavefront times of all channels are based on the same time reference. All calibrated wavefront time points are then integrated to form the cable wavefront time dataset.

[0062] Furthermore, based on the wavefront time differences of each channel in the wavefront time dataset, when selecting valid time points that meet the consistency requirements, the difference between the wavefront time points of any two channels in the wavefront time dataset is calculated, and the distribution of all differences is comprehensively statistically analyzed. A consistency judgment criterion is set, that is, the time difference between two channels must be within a preset reasonable range, which is determined based on the inherent synchronization accuracy of the multi-channel detection system and the physical laws of traveling wave propagation. The difference between the wavefront time point of each channel and the time points of other channels is checked one by one. If the time difference of a certain time point meets the consistency requirements with more than half of the channels, then the time point is determined to be a valid time point and retained in the valid time set.

[0063] Furthermore, when obtaining the traveling wave arrival time of the cable by weighted fusion of valid time points, a corresponding weight is assigned to the channel corresponding to each valid time point based on factors such as the detection accuracy and historical data reliability of each detection channel. Channels with higher detection accuracy and reliability have higher weights for their valid time points. Each valid time point is then correlated with its corresponding weight to obtain a weighted contribution value. The weighted contribution values ​​of all valid time points are then aggregated, and a comprehensive time value is calculated using a fixed fusion logic. This comprehensive time value is the traveling wave arrival time of the cable.

[0064] In summary, by collecting wavefront features from multiple detection channels to obtain an initial wavefront time series, and integrating wavefront time information from different channels, misjudgments caused by interference from a single channel or equipment errors are avoided, providing comprehensive data support for subsequent fusion.

[0065] In summary, the wavefront time of other channels is calibrated using the channel with the best stability as the time reference, eliminating deviations caused by hardware response and transmission delay, so that all time points are based on the same reference, ensuring the accuracy of subsequent calculations.

[0066] In summary, the time difference of each channel is calculated, compared with a reasonable range set based on system accuracy and traveling wave pattern, and valid time points that meet the requirements are retained. Abnormal data caused by interference and faults are eliminated to improve the quality of fused data.

[0067] In summary, by allocating weights based on channel accuracy and reliability, calculating and summarizing the weighted contribution values ​​of effective time points, the high-quality channel data is fully utilized to offset errors and obtain a more accurate traveling wave arrival time, providing precise time parameters for fault location, which aligns with the invention's goal of improving the accuracy and efficiency of anti-interference ranging.

[0068] S5. Based on the arrival time of the traveling wave, determine the fault location of the cable, and perform density clustering fusion on the results of multiple fault locations to obtain the precise fault location of the cable. In this embodiment of the invention, determining the fault location of the cable based on the traveling wave arrival time, and performing density clustering fusion on multiple fault location results to obtain the precise fault location of the cable includes: Based on the cable's line topology, determine the complete transmission path between the two terminals in the cable; Distinguish between overhead line segments and cable line segments in the complete transmission path; The fault location of the cable is determined based on the arrival time of the traveling wave and the wave velocity difference between the overhead line segment and the cable line segment.

[0069] The density clustering and fusion of multiple fault location results to obtain the precise fault location of the cable includes: Based on the spatial distribution characteristics of multiple fault locations, a fault spatial distribution model of the cable is constructed; In the fault spatial distribution model, spatially adjacent location points are divided into the same cluster region; Filter out the effective cluster regions containing the most location points; The precise location of the cable fault point is obtained based on the geometric center of all positioning points in the effective clustering region.

[0070] Specifically, when determining the complete transmission path between two terminals in a cable based on its topology, the cable's topology data is retrieved to clarify the exact locations of the cable's starting and ending terminals, as well as key information such as connecting nodes and branch lines. All possible transmission paths from the starting to the ending terminal are analyzed, eliminating branch lines and backup lines, focusing on the main transmission path corresponding to the fault detection. Combining line laying records and geographical information, the actual route and areas traversed by this main transmission path are confirmed, forming a path description that fully reflects the signal transmission trajectory between the two terminals. This description constitutes the complete transmission path between the two terminals in the cable.

[0071] Furthermore, when distinguishing between overhead line segments and cable line segments in the complete transmission path, the laying method of the complete transmission path is analyzed segment by segment based on the line topology data and laying type records. For overhead line sections, their starting and ending points, as well as characteristics such as material and installation height, are identified. Simultaneously, for cable line sections laid underground or in conduits, their corresponding starting and ending points and laying specifications are determined. By comparing the characteristic identifiers of different laying methods, the complete transmission path is clearly divided into interconnected overhead line segments and cable line segments. Specific information for both segments is recorded separately to ensure no segmentation is omitted or confused.

[0072] Furthermore, based on the arrival time of the traveling wave and the difference in wave velocity between overhead line segments and cable line segments, the traveling wave velocity corresponding to each segment is determined when locating the cable fault. The difference between the two wave velocities is determined based on factors such as line material and laying environment, and has been pre-measured and calibrated. Combining the length information of the complete transmission path and the time difference of the traveling wave arriving at the two terminals, the propagation process of the traveling wave in the overhead line segment and cable line segment is analyzed. By judging the matching relationship between the arrival time difference of the traveling wave and the wave velocity and length of the two line segments, the specific line segment where the traveling wave abruptly changes is located. Then, combining the length and wave velocity of that line segment, the specific location of the fault point from one of the terminals is calculated, and this location is the cable fault location result.

[0073] Specifically, when constructing a cable fault spatial distribution model based on the spatial distribution characteristics of multiple fault locations, the location information corresponding to all fault location results is collected to clarify the specific coordinates of each location point on the cable line. These location points are arranged in the order of the cable line's direction, and spatial characteristics such as the distribution density of each location point and the distance between adjacent location points are marked. Using the complete transmission path of the cable line as the basic framework, the spatial characteristics of all location points are integrated into the framework to form a model that can intuitively present the spatial distribution of all fault location points. This model is the cable fault spatial distribution model.

[0074] Furthermore, in the fault spatial distribution model, when assigning spatially adjacent location points to the same cluster region, a spatial adjacency criterion is set: the distance between two location points must not exceed a preset reasonable range, which is determined based on the fault location error range and the actual line conditions. Each location point in the fault spatial distribution model is examined one by one, and other location points whose distances meet the adjacency criterion are found. These mutually adjacent location points are grouped together. This process is repeated until all location points in the model have been assigned to their corresponding groups, with each group constituting an independent cluster region.

[0075] Furthermore, when selecting the effective cluster regions containing the most location points, the number of location points within each cluster region is counted, and the quantity information for each region is recorded and sorted. The number of location points in all cluster regions is compared to determine the cluster region containing the most location points. The reasonableness of the distribution of location points within this region is verified, ensuring that all location points within the region meet the spatial adjacency requirements and that there are no abnormal location points that significantly deviate from the region's concentration range. Once confirmed, this region is determined to be a valid cluster region.

[0076] In detail, when obtaining the precise location of the cable fault point based on the geometric center of all location points within the effective clustering region, the coordinate information of all location points within the effective clustering region is extracted to determine the spatial position of each location point on the cable line. Through a fixed geometric calculation logic, the coordinates of all location points are combined to determine a central position that balances the spatial distribution of all location points; this central position is the geometric center of all location points. The cable line position corresponding to this geometric center is taken as the final result, which is the precise location of the cable fault point.

[0077] In summary, by clarifying the complete transmission path between two terminals based on the cable line topology, identifying the main transmission path and excluding branches and backup lines, and confirming the actual route by combining laying records and geographical information, this operation can accurately pinpoint the core path of traveling wave propagation, avoiding deviations in fault location direction due to path misjudgment. It provides a clear physical path basis for subsequent segmented analysis and distance calculation, solving the problem of expanded location range caused by ignoring path complexity in existing technologies.

[0078] In summary, distinguishing between overhead line segments and cable line segments within a complete transmission path, and clearly recording the start and end points, material specifications, and laying environment of each segment based on its laying type, is crucial. Since the traveling wave velocities of overhead lines and cable lines differ fundamentally, this segmentation process lays the foundation for subsequent fault location calculations based on these velocity differences. It avoids the positioning errors caused by the use of a uniform wave velocity in existing technologies, ensuring accurate matching of wave velocity parameters with line type.

[0079] In summary, fault location is determined based on the arrival time of the traveling wave and the difference in wave velocity between two line segments. Using the known line length and the time difference between the arrival times of the traveling wave at the two terminals, the propagation process of the traveling wave in different segments is analyzed. The fault segment is located by matching the time difference with wave velocity and length, and the distance to the fault point is calculated by combining the wave velocity and length of the segment. This method fully considers the influence of line type on wave velocity, avoids calculation deviations caused by uniform wave velocity, and makes the fault location results more consistent with reality. It provides reliable preliminary location data for subsequent density clustering fusion to improve accuracy, aligning with the invention's core objective of "improving the accuracy of anti-interference fault ranging."

[0080] In summary, a fault spatial distribution model is constructed based on the spatial distribution characteristics of multiple fault locations. This model integrates the location information of all locations, labels the distribution density and adjacent spacing of each location according to the cable route, and integrates these spatial features within the framework of the complete transmission path of the cable line. This model can intuitively present the spatial distribution patterns of all location results, avoiding the problem of difficulty in judging the overall trend from single or scattered locations. It provides a clear spatial reference framework for subsequent cluster analysis, addressing the deficiency of systematic integration of location results in existing technologies.

[0081] In summary, the fault spatial distribution model groups spatially adjacent location points into the same cluster region. Adjacency criteria are set based on the fault location error range and the actual line conditions, and location points with acceptable spacing are grouped together. This approach distinguishes between concentrated, valid location points and isolated, abnormal location points, reducing the interference of abnormal data on the final results. This ensures that subsequent analysis focuses on a consistent set of location points, improving the reliability of the location results.

[0082] In summary, the effective clustering region containing the most location points is selected. By counting and ranking the number of location points in each cluster, the region with the largest number of points is determined, and the rationality of the distribution of location points within this region is verified. The clustering region with the largest number of points represents the consensus of most location results, and its reliability is much higher than that of other smaller-scale regions. Selecting this region as the effective clustering region can further eliminate scattered location results caused by random errors and interference, ensuring that subsequent calculations are based on highly reliable location data.

[0083] In summary, the precise fault location is obtained based on the geometric center of all positioning points within the effective clustering region. The center position is determined by integrating the coordinates of all positioning points within the region and using a calculation logic that balances spatial distribution. This geometric center can offset the random and systematic errors of individual positioning points, making the final result closer to the actual fault location. This solves the problems of high dispersion and low accuracy caused by the lack of fusion of multiple positioning results in existing technologies, providing a clear location basis for accurate fault diagnosis. This aligns with the core objective of this invention: "improving the accuracy and efficiency of anti-interference fault ranging."

[0084] S6. Perform wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

[0085] In this embodiment of the invention, the step of performing wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, in order to obtain the diagnostic result of the fault point, includes: Based on the characteristics of the mixed sections of the cable, a segmented compensation mapping relationship between line type distribution and wave velocity difference is established; Based on the segmented compensation mapping relationship, segmented wave velocity compensation is performed on the precise fault location to obtain the preliminary compensation result of the cable. Based on the multi-dimensional verification results of the preliminary compensation results, the preliminary compensation results are dynamically adjusted to obtain the optimized actual distance of the fault point; By combining the optimized actual distance to the fault point, line log data, and operating parameters, a diagnostic result for the fault point in the cable is generated.

[0086] Specifically, when establishing a segmented compensation mapping relationship between line type distribution and wave velocity differences based on the characteristics of mixed cable sections, the specific composition of the mixed cable sections is first clarified, defining the distribution range, material specifications, and laying environment of overhead line sections and cable line sections. The traveling wave velocities corresponding to different line types are determined through measured or historical data, and the wave velocity differences of various line sections and their impact on fault distance calculation are analyzed. The line type distribution information is then correlated one-to-one with the corresponding wave velocity compensation coefficients to form a mapping rule based on line segmentation; this rule constitutes the segmented compensation mapping relationship between line type distribution and wave velocity differences.

[0087] Furthermore, based on the segmented compensation mapping relationship, segmented wave velocity compensation is performed on the precise fault location to obtain the preliminary compensation result for the cable. First, the line segment where the precise fault location is located and its adjacent segments are determined. According to the segmented compensation mapping relationship, the wave velocity compensation coefficient corresponding to each relevant segment is extracted. Based on the actual crossing situation of the fault point in each segment, the distance value of the precise fault location is corrected segment by segment. During the correction process, the compensation rules in the mapping relationship are strictly followed to ensure that the wave velocity difference in each segment is compensated accordingly. The corrected distance value is the preliminary compensation result for the cable.

[0088] Furthermore, based on the multi-dimensional verification results of the preliminary compensation results, the preliminary compensation results are dynamically adjusted. When the optimized actual distance to the fault point is obtained, the preliminary compensation results are verified from multiple dimensions, including line length calibration, comparison with historical fault data, and verification of traveling wave propagation time. If the verification reveals a deviation between the preliminary compensation results and the reference data for a certain dimension, the cause of the deviation is analyzed, and the compensation coefficient or segmentation is fine-tuned in conjunction with the segmented compensation mapping relationship and the actual line characteristics. The verification and adjustment process is repeated until the preliminary compensation results are within a reasonable range in all dimensions. The final distance value obtained is the optimized actual distance to the fault point.

[0089] Furthermore, when generating diagnostic results for fault points in cables by combining the optimized actual distance to the fault point, line ledger data, and operating parameters, the line ledger data is retrieved to clarify information such as line design parameters, laying years, and maintenance records at the location of the fault point.

[0090] In detail, real-time operating parameters of the cable are collected, including voltage, current, and load conditions, and the correlation between these parameters and the occurrence of faults is analyzed. The optimized actual distance of the fault point is integrated with the ledger data and operating parameters to clarify the specific geographical location of the fault point, the line section to which it belongs, the possible causes of the fault, and the scope of impact, forming a complete report containing this key information. This report is the diagnosis result of the fault point in the cable.

[0091] In summary, based on the characteristics of mixed cable sections, the system correlates line types with wave velocity compensation coefficients, breaking the limitations of single wave velocity correction and providing rules for accurate compensation, thus avoiding distance deviations caused by differences in line types. The fault location segment is determined according to the mapping relationship, and the distance is corrected segment by segment to match the actual propagation characteristics of the line, eliminating the influence of wave velocity differences and obtaining preliminary compensation results.

[0092] In summary, preliminary results were verified using dimensions such as line length, historical data, and propagation time. Any deviations were fine-tuned by adjusting the compensation coefficients or segmentation until the results met compliance, thus resolving the issue of insufficient accuracy after compensation. By combining optimized distances, line records, and operating parameters, the location, cause, and impact of faults were identified, providing comprehensive guidance for troubleshooting and maintenance, enhancing the value of ranging applications, and aligning with the core objectives of the document.

[0093] like Figure 2 The diagram shown is a functional block diagram of an anti-interference fault location device provided in an embodiment of the present invention.

[0094] The anti-interference fault location device 100 described in this invention can be installed in an electronic device. Depending on the functions implemented, the anti-interference fault location device 100 may include a data acquisition module 101, a data filtering module 102, a feature extraction module 103, a traveling wave arrival time calculation module 104, a fault location module 105, and a location compensation module 106. The module described in this invention can also be called a unit, which refers to a series of computer program segments that can be executed by the processor of an electronic device and can perform a fixed function, and are stored in the memory of the electronic device.

[0095] In this embodiment, the functions of each module / unit are as follows: The data acquisition module 101 is used to acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and obtain the original traveling wave data of the cable. The data filtering module 102 is used to adaptively filter the original traveling wave data to obtain the enhanced traveling wave data of the cable. The feature extraction module 103 is used to extract wavefront features from the enhanced traveling wave data; The traveling wave arrival time calculation module 104 is used to perform multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. The fault location module 105 is used to determine the fault location of the cable based on the arrival time of the traveling wave, and to perform density clustering fusion on the results of multiple fault locations to obtain the precise fault location of the cable. The positioning compensation module 106 is used to perform wave velocity compensation on the precise fault point location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

[0096] In the several embodiments provided by this invention, it should be understood that the disclosed methods and apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0097] The modules described as separate components may or may not be physically separate. The components shown as modules 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.

[0098] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0099] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0100] This application embodiment can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is the theory, method, technology, and application device that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. An anti-interference fault location method, characterized in that, The method includes: S1. Acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and obtain the original traveling wave data of the cable; S2. Adaptive filtering is performed on the original traveling wave data to obtain the enhanced traveling wave data of the cable; S3. Extract wavefront features from the enhanced traveling wave data; S4. Perform multi-channel wavefront time fusion on the points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. S5. Based on the arrival time of the traveling wave, determine the fault location of the cable, and perform density clustering fusion on the results of multiple fault locations to obtain the precise fault location of the cable. S6. Perform wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

2. The anti-interference fault location method as described in claim 1, characterized in that, The transient voltage traveling wave signal generated by the acquisition cable when a fault occurs is used to obtain the raw traveling wave data of the cable, including: The voltage signals of the three phase conductors of the cable are simultaneously acquired by a multi-channel synchronous acquisition device to obtain the raw three-phase voltage data of the cable. The original three-phase voltage data is amplified and common-mode suppressed to obtain the conditioned voltage signal of the cable. The conditioned voltage signal is converted from analog to digital to obtain digitized transient voltage waveform data; The digitized transient voltage waveform data is timestamped to obtain the original traveling wave data of the cable.

3. The anti-interference fault location method as described in claim 1, characterized in that, The step of adaptively filtering the original traveling wave data to obtain the enhanced traveling wave data of the cable includes: The interference component characteristics in the original traveling wave data are identified to obtain the interference distribution information of the cable; Based on the interference distribution information, the corresponding filter parameters are configured to obtain an optimized filter configuration; The original traveling wave data is filtered in multiple stages using the optimized filter configuration to obtain the preliminary processed signal data of the cable. The quality of the pre-processed signal data is evaluated, and the filter parameters are adjusted based on the evaluation results to obtain enhanced traveling wave data that meets the quality requirements.

4. The anti-interference fault location method as described in claim 3, characterized in that, The step of performing a quality assessment on the pre-processed signal data and adjusting the filter parameters based on the quality assessment results includes: Feature extraction is performed on the pre-processed signal data to obtain quality assessment indicators of signal-to-noise ratio and waveform integrity in the original traveling wave data; The quality assessment indicators are compared and analyzed with the preset quality standards to obtain the quality deviation information of the preliminary processed signal data; Based on the quality deviation information, a parameter adjustment scheme is generated for the notch filter bandwidth and the number of wavelet decomposition layers. Based on the parameter adjustment scheme, the configuration parameters of the filter are updated to obtain the optimized filter configuration.

5. The anti-interference fault location method as described in claim 1, characterized in that, Extracting wavefront features from the enhanced traveling wave data includes: The enhanced traveling wave data is differentiated to obtain the signal rate of change derivative sequence of the cable; Based on the statistical characteristics of the derivative sequence of the signal rate of change, a threshold standard for the cable is established; Based on the threshold criteria, identify the characteristic abrupt change points in the derivative sequence of the signal rate of change; The true and valid feature mutation points are output as the wavefront characteristics of the cable.

6. The anti-interference fault location method as described in claim 1, characterized in that, The step of performing multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable includes: The initial wavefront time series of the cable is obtained by collecting wavefront features identified by multiple detection channels; Time-align the initial wavefront time series to the wavefront time dataset of the cable; Based on the wavefront time difference values ​​of each channel in the wavefront time dataset, valid time points that meet the consistency requirements are selected. The effective time points are weighted and fused to obtain the traveling wave arrival time of the cable.

7. The anti-interference fault location method as described in claim 1, characterized in that, The process of determining the fault location of the cable based on the traveling wave arrival time, and performing density clustering fusion on multiple fault location results to obtain the precise fault location of the cable includes: Based on the cable's line topology, determine the complete transmission path between the two terminals in the cable; Distinguish between overhead line segments and cable line segments in the complete transmission path; The fault location of the cable is determined based on the arrival time of the traveling wave and the wave velocity difference between the overhead line segment and the cable line segment.

8. The anti-interference fault location method as described in claim 7, characterized in that, The density clustering and fusion of multiple fault location results to obtain the precise fault location of the cable includes: Based on the spatial distribution characteristics of multiple fault locations, a fault spatial distribution model of the cable is constructed; In the fault spatial distribution model, spatially adjacent location points are divided into the same cluster region; Filter out the effective cluster regions containing the most location points; The precise location of the cable fault point is obtained based on the geometric center of all positioning points in the effective clustering region.

9. The anti-interference fault location method as described in claim 8, characterized in that, The process of performing wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, in order to obtain the diagnostic result of the fault point, includes: Based on the characteristics of the mixed sections of the cable, a segmented compensation mapping relationship between line type distribution and wave velocity difference is established; Based on the segmented compensation mapping relationship, segmented wave velocity compensation is performed on the precise fault location to obtain the preliminary compensation result of the cable. Based on the multi-dimensional verification results of the preliminary compensation results, the preliminary compensation results are dynamically adjusted to obtain the optimized actual distance of the fault point; By combining the optimized actual distance to the fault point, line log data, and operating parameters, a diagnostic result for the fault point in the cable is generated.

10. An anti-interference fault location device, characterized in that, The device includes: The data acquisition module is used to acquire the transient voltage traveling wave signal generated by the cable when a fault occurs, and to obtain the original traveling wave data of the cable. A data filtering module is used to adaptively filter the original traveling wave data to obtain the enhanced traveling wave data of the cable. The feature extraction module is used to extract wavefront features from the enhanced traveling wave data; The traveling wave arrival time calculation module is used to perform multi-channel wavefront time fusion on points in the wavefront features where the first derivative exceeds a preset threshold to obtain the traveling wave arrival time of the cable. The fault location module is used to determine the fault location of the cable based on the arrival time of the traveling wave, and to perform density clustering fusion on the results of multiple fault locations to obtain the precise location of the fault point of the cable. The positioning compensation module is used to perform wave velocity compensation on the precise fault location to restore the actual distance of the fault point in the cable, so as to obtain the diagnosis result of the fault point.

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