276results about "Fault location by pulse reflection methods" patented technology

A method for locating a high-impedance ground fault of a smart distribution network with topology change adaptation includes: acquiring a fault traveling wave sample within a specified time window after a fault occurs, and performing continuous wavelet transform on the fault traveling wave sample to obtain traveling wave full waveform feature information; establishing a graph structure of a power distribution network, obtaining a corresponding adjacency matrix, and obtaining node position and structure encoding information in the graph structure through graph random walk and graph Laplace transform; concatenating the node position, the structure encoding information and the traveling wave full waveform feature information to obtain a node feature, and inputting the node feature and an edge feature into the graph structure to establish a graph sample data set; constructing and training a Graph Transformer model; and calling the trained Graph Transformer model to locate a fault in to-be-detected sample data.

The invention relates to the technical field of fault monitoring, in particular to a power transmission line fault monitoring and positioning method, system and device and a medium. The method comprises the following steps: firstly, performing digital conversion on an original current signal to obtain time sequence data, and then identifying and classifying fault events through threshold detection and a feature extraction algorithm to obtain classification labels of fault types; then, based on the classification label, establishing a traveling wave propagation model and carrying out time difference calculation, carrying out clustering analysis on a plurality of wave head data in a preset time window, and judging whether the fault is a single-point fault or a multi-point fault through a clustering result; and finally, a positioning result is transmitted to the central server for comprehensive verification and alarm management, and a final fault response is formed. By introducing a time series data analysis and clustering judgment mechanism, the fault type can be accurately identified, single-point and multi-point fault conditions can be effectively distinguished, and meanwhile, the reliability of a positioning result is improved through comprehensive verification of the central server.

The invention relates to a weak current cable fault positioning method and system, and the method comprises the steps: preliminarily locking a fault region through monitoring the axial stress change in real time, injecting a low-frequency pulse signal in a target section, analyzing the reflection waveform characteristics, and extracting the waveform distortion characteristics in a reflection signal; dynamically adjusting the output impedance based on the amplitude attenuation and time delay relationship, and if the dynamically adjusted output impedance cannot enable the output impedance of the injected low-frequency pulse signal to be synchronous with the impedance change trend of the cable, marking as an impedance mismatch point; after an impedance mismatch point is identified, other interferences are eliminated through multi-band signal attenuation difference analysis, and the position of a fault point is determined; the system is used for implementing the method. According to the method and system, stress monitoring and electric signal detection are combined, the detection range is remarkably shortened, the positioning precision and the detection accuracy are improved, and the method and system are suitable for weak current cable fault diagnosis in a complex environment.

The invention discloses a self-adaptive fault reflection method and device based on adjustable excitation frequency, and belongs to the technical field of cable fault detection and positioning. The method comprises the following steps: injecting an excitation signal which can be adjusted in a range of 1kHz-10MHz through an adjustable impedance matching network; collecting a reflected signal and calculating an SNR (f) curve; optimizing by adopting a particle swarm optimization algorithm and taking maximization of a signal-to-noise ratio as a target, and determining an optimal excitation frequency; and finally, calculating the fault position and type based on the optimal frequency. The particle swarm optimization algorithm is adopted to perform adaptive optimization on the excitation frequency, and the adjustable impedance matching network is combined to form a closed-loop adaptive detection framework of excitation-acquisition-analysis-optimization-re-excitation, so that the excitation frequency can be automatically adjusted according to a real-time detection result, and the detection accuracy is improved. And the fault detection sensitivity, the positioning precision and the energy efficiency are obviously improved.

The invention discloses a power grid fault positioning system and method based on traveling wave distance measurement, relates to the technical field of fault analysis, and solves the technical problems that traveling wave feature analysis, temperature compensation and high-precision synchronization technologies are not effectively integrated, and rapid and accurate fault positioning of a smart power grid is difficult to meet. Through the technical combination of dynamic temperature compensation, high-precision time synchronization and intelligent fault classification, the bottlenecks of traditional traveling wave distance measurement in the aspects of precision, reliability and intelligence are systematically solved, temperature sensors are deployed at key nodes of a cable, the temperature is monitored in real time, the wave speed is dynamically corrected through a formula, the overall error is reduced, and the fault location accuracy is improved. Meanwhile, an optical fiber two-way time transmission method is combined, transmission delay errors are reduced, synchronization reliability is improved, finally, a mapping library is constructed through laboratory simulation and field data, a Euclidean distance matching algorithm is combined, fault reasons are automatically recognized, and rapid positioning of the faults and accurate recognition of the fault reasons are achieved.

The invention discloses a power distribution network fault positioning method and device based on a satellite time service inverter, and belongs to the technical field of power system fault diagnosis, and the method comprises the steps: obtaining a time service signal of a satellite navigation system, decoding the time service signal to generate a unified space-time reference, distributing the unified space-time reference to a plurality of inverter nodes in a power distribution network, and forming a cooperative measurement network; a coding sequence current signal is injected into a power distribution network line through a master control inverter node; synchronously acquiring response voltage traveling wave data by each inverter node, performing cross-correlation analysis on the response voltage traveling wave data and the coded sequence current signal, and extracting propagation time delay of each inverter node; and correcting the reference line wave velocity by using the current line parameters and the current meteorological data, and calculating fault point position data in combination with propagation time delay. According to the method, an inverter cooperative measurement network is constructed by using satellite time service, a coding sequence current signal is actively injected, and a real-time wave velocity is corrected by combining an intelligent model, so that rapid, accurate and high-reliability positioning of a power distribution network fault can be realized.

The invention belongs to the technical field of power cable fault positioning. The invention discloses a TDR power cable global fault positioning method based on multi-frequency cooperative excitation and environment adaptive correction. The method comprises the following steps: 1) multi-frequency pulse cooperative injection and signal acquisition; 2) environment parameter dynamic sensing and speed correction: embedding a miniature temperature and humidity sensor and a cable insulation state monitoring unit along the cable at an interval of 500m, and collecting laying environment temperature, humidity and insulation material dielectric constant change data in real time; constructing a dynamic speed correction formula based on a preset environment-dielectric constant correlation model; according to the method, the complex fault positioning precision is improved, the environment and scene adaptability is enhanced, and the troubleshooting efficiency is optimized.

The invention discloses a power distribution network line fault positioning system based on multi-source information fusion, which relates to the technical field of power system operation and maintenance and comprises a data acquisition module, a data preprocessing module, an electric network topology management module, a fault prediction module, a fault judgment module and a man-machine interaction and alarm module. The method comprises the following steps: acquiring running state information from a power distribution network in real time, generating a structured multi-dimensional information database according to the running state information acquired by a data acquisition module, and performing time alignment, format standardization and feature vector construction on the acquired running state information to generate the structured multi-dimensional information database; according to the method, a fault section is preliminarily judged according to fault features, a fault state prediction model is constructed, a multi-dimensional information database is used for estimating state variables of the model, and the method aims at overcoming the defects that in the prior art, fault positioning fuzziness and reliability are insufficient due to the fact that a single information source is relied on.

The invention discloses a power transmission line fault identification method and device based on artificial intelligence, and relates to the technical field of power transmission line fault identification. Determining line data of the target area, performing data acquisition according to the line data to obtain an original traveling wave signal, and filtering the original traveling wave signal to obtain a time domain signal; performing adaptive variational mode decomposition on the time domain signal to obtain a mode component, and performing calculation according to the mode component to obtain a fault point; and determining an inspection scheme according to the fault point, executing the inspection scheme to obtain a fault point image, and performing alarm judgment on the fault point image through artificial intelligence. Line data and traveling wave signals are accurately collected, noise is filtered by adopting an advanced filtering technology, and the signal quality is improved; adaptive variational mode decomposition is utilized to accurately extract a mode component, and the fault point positioning precision is enhanced; faults are quickly and accurately judged by combining artificial intelligence image recognition, automatic operation and maintenance are realized, and the operation and maintenance efficiency of the power transmission line and the stability of the power system are improved.

The invention relates to the technical field of electromagnetic measurement, and discloses a line partial discharge positioning method and system based on pulse signal analysis, and the method comprises the steps: carrying out the band-pass filtering of pulse signal data, and obtaining a preprocessing signal; constructing a waveform template library based on the historical partial discharge pulse waveform data; screening out a partial discharge pulse and an interference pulse in the preprocessed signal to obtain a pulse matching result of the preprocessed signal; determining time difference data of the preprocessed signal according to time differences of pulses reaching different sensors in the pulse matching result; constructing an initial propagation velocity model according to the parameters and the environment data, performing iterative optimization on the initial propagation velocity model according to the time difference data, and determining an initial position of a partial discharge source in the line; correcting the initial propagation velocity model according to the initial position and the actual propagation path to obtain a target propagation model, and determining position coordinates of a partial discharge source in the target line according to the target propagation model; according to the invention, the accuracy of line partial discharge positioning can be improved.

The invention discloses an FTU-based power distribution network fault detection method and system, and relates to the field of power distribution network fault detection, and the method comprises the steps: employing a wavelet transform technology to analyze electrical parameters, recognizing a fault line of a power distribution network, transmitting a traveling wave to an end point of the fault line through a traveling wave transmitter, and positioning a fault position point of the fault line of the power distribution network; extracting influence parameters based on a fault reason matching result, judging a probability coefficient of a power failure condition in the power supply area of the power distribution network in the target time period, and evaluating the power supply reliability of the power distribution network according to the probability coefficient; and based on the power supply reliability, using the fault terminal device to control the switch device to perform circuit breaking operation, isolating the power distribution network fault line, generating a personnel scheduling instruction, and implementing power distribution network fault line emergency repair processing. According to the method, a highly fine recording data analysis and multi-dimensional dynamic feature extraction mechanism is introduced, so that deep reasoning from a fault phenomenon to a fault cause is realized.

The invention relates to the technical field of power system protection, in particular to an underground power distribution network single-phase grounding protection system and method based on a signal injection method. The system comprises a signal acquisition module, a measurement and control protection module and an online monitoring module. According to the invention, by injecting the independent direct current signal and combining a zero-sequence fundamental wave time sequence identification algorithm and a traveling wave distance measurement method, rapid detection, high-precision positioning and selective protection of the single-phase earth fault of the underground low-voltage power distribution network are realized, and the method is suitable for complex environments such as coal mines and metal mines; through insulation value on-line monitoring and electric leakage protection, the ground insulation value level of a line is reflected to the voltage change of an additional direct current signal and a reactor neutral point. A zero-sequence fundamental wave time sequence identification model is adopted for electric leakage fault judgment so as to judge the fault type. By outputting a relay signal, on-off control is performed on a protected branch, so that a fault line can be quickly cut off when a fault occurs, and equipment and a bus are protected from being damaged by the fault.

The invention relates to the technical field of power systems, and discloses a cable defect positioning method, system and device, a medium and a product, and the method comprises the steps: taking a Gaussian envelope linear chirp signal as an initial incident signal for frequency domain reflection, optimizing the signal characteristic parameter of the initial incident signal, obtaining an incident signal, and carrying out the positioning of a cable defect. The method comprises the following steps: exciting a target cable through an incident signal, obtaining a reflection signal on a preset measuring point of the target cable, respectively carrying out time-frequency conversion on the incident signal and the reflection signal to obtain an incident time-frequency domain signal and a reflection time-frequency domain signal, and obtaining a time-frequency domain signal and a reflection time-frequency domain signal on the basis of a cross-correlation function. The peak position of a cross-correlation function is determined through the incident time-frequency domain signal and the reflected time-frequency domain signal, the signal propagation defect time delay of the target cable is determined according to the peak position of the cross-correlation function, and the defect position of the target cable is determined according to the signal propagation defect time delay and the propagation speed of the incident signal. Therefore, surrounding signal interference can be filtered out, and the accuracy of cable defect positioning is improved.

The invention provides a line loss reason analysis and positioning method and system based on artificial intelligence and a medium, and relates to the technical field of power system management.The method comprises the steps that when the bus loss rate of a target station area exceeds a preset line loss threshold value, an excitation sequence is issued to a general meter, a circuit breaker and a user electricity meter of the target station area, respectively obtaining corresponding transient response data, and further constructing a dynamic topological graph of the target transformer area; and a topological structure is optimized by combining a graph neural network and an attention mechanism, and abnormal connection points are detected. And determining downstream associated user electric meters, and calculating the power utilization abnormity score based on the load data. And injecting a steep front traveling wave signal into the electric meter with the highest score to obtain a reflection characteristic parameter. And performing iterative analysis by using a Double DQN reinforcement learning algorithm, determining a fault point, a line loss reason type and confidence, and realizing efficient and accurate line loss reason positioning and analysis. According to the invention, efficient and accurate troubleshooting of line loss reasons is realized.

Disclosed is a method for predicting faults in an electric grid, the method comprising: detecting one or more events (102) that are precursors of one or more faults in the electric grid, the detection is based parameters associated with signals propagating in the electric grid or radiation produced by components in the electric grid; determining one or more locations (104), in the electric grid where the one or more events are detected, the determination is based on one or more of: a pattern of detection of the one or more events, weather conditions, traveling wave analysis, or location-specific sensor measurements; and generating an alert (100) that includes the one or more events, the one or more locations, and one or more components (106) of the electric grid in which the one or more events are detected, the alert corresponds to predictions of occurrences of the one or more faults.

The invention is suitable for the technical field of distribution network detection, and provides a distribution network overhead line partial discharge integrated live detection system based on a ubiquitous Internet of Things architecture, which comprises a pulse signal detection end, an edge gateway and a cloud monitoring platform, the pulse signal detection end is used for detecting a partial discharge pulse signal of the overhead line and transmitting the partial discharge pulse signal to the edge gateway; the edge gateway comprises a synchronization pulse trigger module, a time calibration module and an edge analysis module. The generation module is used for generating a positioning distribution diagram of partial discharge points; the cloud monitoring platform comprises a multi-terminal data fusion module, a risk assessment module and a result feedback module; the server is used for fusing the positioning distribution map and the pulse characteristics, outputting a global discharge point correction distribution map, identifying a discharge type based on a discharge characteristic spectrogram, generating an insulation state evaluation result and feeding back the evaluation result to a terminal user; and a high-reliability, high-efficiency and low-cost solution is provided for the management and control of the insulation state of the distribution network.

The invention relates to an anti-loose monitoring method for electric power fitting wire clamps, which comprises the following steps of: injecting a high-frequency probe signal into a preset conductor of a power transmission line serving as a sensing medium from a detection end, and receiving a reflected signal sequence generated by a plurality of electric power fitting wire clamps along the line due to discontinuous impedance; the round-trip time of each reflected signal in the sequence is analyzed to accurately position each wire clamp, and the reflection characteristics of the wire clamps are extracted to represent the real-time connection state. And comparing the real-time reflection characteristic with a pre-stored baseline reflection characteristic of the wire clamp in a fastening state, and determining that the wire clamp at the corresponding position is loosened when the difference between the real-time reflection characteristic and the pre-stored baseline reflection characteristic exceeds a preset threshold value. According to the invention, remote, passive and full-coverage monitoring of the fastening state of a plurality of electric power fitting wire clamps on a power transmission line can be realized, and the technical problems of low manual inspection efficiency and strong subjectivity, and high cost, difficult power supply, complex maintenance and the like of an online monitoring device in the prior art are solved.

The invention relates to the technical field of electrical variable measurement, in particular to a power distribution overhead line fault traveling wave positioning anti-electromagnetic interference method and system and a medium. According to the method, a broadband equivalent circuit model of a power distribution overhead line is constructed based on a vector matching method and is used for simulating transmission characteristics of fault traveling waves and switching operation overvoltage; performing multi-scale decomposition on the acquired signals by adopting a wavelet transform algorithm, extracting disturbance signal parameters, and calculating traveling wave propagation characteristics according to different fault types and switch working conditions; constructing an electromagnetic disturbance propagation coupling model, and performing time-frequency domain analysis by taking the traveling wave propagation characteristics, the disturbance signal parameters and the line environment parameters as input to obtain coupling characteristics of electromagnetic disturbance; carrying out numerical simulation by utilizing electromagnetic field simulation software, analyzing the influence of line environment parameters on coupling characteristics, and optimizing model parameters; and finally, analyzing the coupling characteristics of electromagnetic disturbance, eliminating the influence of electromagnetic interference on the traveling wave signal through a reverse decoupling algorithm, and achieving the accurate fault positioning of the power distribution overhead line.

The invention discloses a photovoltaic cable health state assessment method and system, and the system comprises a signal collection module which is disposed at a key node of a cable, and comprises an ultra-wideband pulse sensor, an infrared thermometer, and an illumination sensor; the edge processing module is used for constructing a state characteristic curve and identifying a target sample time interval; the cloud analysis engine is used for executing defect contribution simulation value extraction and thermal-electric coupling model iterative optimization; according to the scheme, multi-dimensional signals such as current, voltage, partial discharge pulse, temperature and illumination intensity are synchronously collected through a distributed sensor network, a multi-parameter evaluation system including amplitude, phase and temperature is constructed, and the health state level, the defect position distribution and the simulation value change trend are displayed through multi-dimensional signal fusion and multi-parameter analysis. And the detection accuracy and comprehensiveness are improved.

The invention relates to the technical field of power system relay protection, in particular to a power transmission line single-end fault positioning method and system. The method comprises the following steps: taking an envelope zero crossing point of an initial transient traveling wave signal as an attenuation ending moment; taking the moment from the occurrence moment of the initial transient traveling wave signal to the attenuation ending moment as an analysis time window; taking the duration of the analysis time window as the attenuation duration of the initial transient traveling wave signal; taking the maximum energy peak value as a resonant frequency identification reference threshold value, searching whether the energy of other frequency peak values greater than the resonant frequency identification threshold value exists or not, and if so, judging whether the initial transient traveling wave signal has resonant interference or not based on the attenuation duration of the initial transient traveling wave signal; if yes, designing a filter for the frequency component, and filtering the initial transient traveling wave signal; and obtaining a fault positioning result of the power transmission line based on the filtered transient traveling wave signal. According to the invention, the single-end fault positioning precision is effectively improved.

The invention relates to the technical field of cable fault detection and positioning of a power system, and discloses a cable defect positioning method based on a traveling wave positioning technology, which comprises the following steps of: S1, acquiring a traveling wave signal generated by a cable due to a partial discharge defect by using a sensor; s2, analyzing and processing the acquired traveling wave signal, extracting a characteristic signal, and performing quantitative correction on the partial discharge capacity; s3, based on the obtained feature information, establishing a traveling wave propagation model in combination with the characteristics of the cable, and correcting the traveling wave propagation speed according to the cable type and the laying environment; s4, according to a pulse reflection principle, determining a time difference generated by propagation of the traveling wave in the cable; and S5, spreading related information according to the time difference and traveling waves. According to the method, the sensors are sequentially executed to collect the cable local discharge wave signals, so that the problems that the positioning process is disordered and the result reliability is insufficient due to the fact that scattered and non-coherent operation steps are mostly adopted in a traditional cable defect positioning method are solved.

The invention relates to the field of electrical system fault detection, and provides a cable fault positioning method and system based on neural network learning. The method comprises the following steps: acquiring a cable traveling wave signal and preprocessing the cable traveling wave signal to obtain a preprocessed traveling wave signal; performing high-speed parallel acquisition on the preprocessed traveling wave signal to obtain multi-channel digital traveling wave data; performing multi-resolution decomposition on the multi-channel digital traveling wave data through a fast wavelet transform algorithm, and performing feature extraction on a wavelet coefficient obtained through decomposition to obtain a fault feature vector; and carrying out classification identification on the fault feature vector through a multilayer perceptron neural network, and carrying out fault position calculation on a classification result to obtain a fault positioning result. According to the invention, the cable fault positioning precision and reliability are improved.

The invention discloses a cable defect early warning method and device, terminal equipment and a storage medium, and belongs to the technical field of cable defect early warning, and the method comprises the steps: carrying out the frequency sweeping test of an equivalent circuit model, generating a reflection coefficient spectrum, separating a low-frequency component from the reflection coefficient spectrum, and taking the low-frequency component as a head-end reflection coefficient, through combination of the head end reflection coefficient, the internal resistance of the test equipment and the cable impedance, equivalent impedance at the joint of the test fixture and the head end of the cable is obtained through quantification, and an original reflection coefficient spectrum is corrected according to the equivalent impedance, so that impedance mismatch of the test fixture in the test process is eliminated. The corrected reflection coefficient spectrum can reflect the impedance of the cable body more accurately, so that the subsequently obtained time domain response can reflect the defect condition of the cable body more truly, and the accuracy of cable defect early warning is improved. The problem that the accuracy of cable defect early warning is low due to the fact that the original reflection coefficient spectrum cannot be corrected in the prior art can be solved.

Systems and methods for determining a location of a fault in a power delivery system are provided. Such a method may include receiving several single-end traveling wave fault location values and a single-end impedance fault location value based on measurements from a first intelligent electronic device at a local terminal. Based on a relationship between the single-end traveling wave fault location values, the single-end impedance fault location value, a location of the local terminal, and the location of the remote terminal, one of the several single-end traveling wave fault location values may be selected as a fault location value of highest confidence among the several single-end traveling wave fault location values.

The embodiment of the invention discloses a cable fault detection method and device based on noise reduction processing and a medium, and relates to the technical field of noise reduction, and the method comprises the steps: collecting a target reflection signal, and obtaining a first noise reduction reflection signal after the preliminary noise reduction processing of the target reflection signal, removing noise pseudo peaks in the first noise reduction reflection signal, and determining at least one candidate peak section; and performing screening in the candidate wave crest section through a correlation coefficient between the candidate wave crest section and a pre-acquired incident signal, determining a fault reflection pulse, and determining a second noise reduction reflection signal based on the fault reflection pulse so as to perform cable fault detection. The background noise level is effectively reduced through preliminary noise reduction processing, key features of fault signals are reserved at the same time, and real fault reflection pulses and noise pseudo peaks are distinguished essentially by calculating correlation coefficients between candidate wave crest sections and incident signals.

The invention relates to a computer-implemented method (100) for an analysis (10-60) of an object, which is based on a measurement of the object with a measurement signal, a reflection signal based on the measurement, and a simulation of the object with a simulation measurement signal based on the measurement signal and a resulting simulation reflection signal, wherein the object simulation is post-processed by a correction signal based on the reflection signal and the simulation reflection signal, comprising the steps: temporally shifting (110) the reflection signal and / or the simulation reflection signal such that a difference between the two resulting signals is less than a predetermined difference threshold in at least one predetermined time interval, and determining the correction signal based on the resulting signal(s).and / or adjusting (120) losses in the modeling of the object simulation based on a time course of the reflection signal and / or based on at least one provided reference line impedance ZR, a provided attenuation constant and / or a provided loss factor of a material used for at least one object simulation section of the object simulation.

The invention relates to a broadband impedance spectroscopy cable fault identification method and system and a storage medium, and the method comprises the steps: building a cable equivalent model according to any preset cable fault type; frequency sweep signals are input into the model, parameters of a cable core, a sheath and a steel armor under different frequency sweep signals are obtained, input impedance of the head end of the cable under different frequency sweep signals is calculated based on a cable modulus matrix and an input impedance formula, and a fault broadband impedance amplitude spectrum and a phase spectrum are drawn; repeating the steps to obtain a broadband impedance amplitude spectrum and a phase spectrum of the cable fault; the input impedance of an actual cable is collected in real time, a real-time broadband impedance amplitude spectrum and a real-time broadband impedance phase spectrum are drawn and compared with a cable fault broadband impedance amplitude spectrum and a cable fault phase spectrum, and the cable fault type and the distance between a fault point and the head end are recognized. Compared with the prior art, rapid cable fault identification and fault point determination are realized.

The invention relates to a power distribution network fault positioning method combined with multi-terminal traveling wave sampling and a terminal. The method comprises the following steps: synchronously acquiring a transient interference spectrum excited by a network disturbance singular point; normalizing the transient interference spectrum, and extracting a high-dimensional spectrum feature vector from the transient interference spectrum; for each candidate singular point, predicting a theoretical spectrum feature vector of the candidate singular point through a forward propagation operator, and calculating a holographic coherence index between the theoretical spectrum feature vector and an actually observed spectrum feature vector, thereby iteratively reconstructing a singular point holographic data volume representing global fault probability distribution; and carrying out image decoding analysis on the singular point holographic data body, and determining the accurate position of the network disturbance singular point by searching a global maximum value point. According to the method, the fault positioning problem is converted into an image reconstruction and understanding problem, and the positioning precision and robustness are remarkably improved by using the complete information of the traveling wave signal instead of single time information.

The invention relates to the technical field of power grid faults, in particular to a coal mine power grid fault positioning method, which comprises the following steps: collecting transient current traveling wave signals generated when a fault occurs; executing a first layer of PSO to adaptively find an optimal parameter combination for the VMD, and processing a transient current traveling wave signal based on MRSVD to obtain an input signal of the VMD; inputting an input signal into VMD based on the optimal parameter combination, decomposing to obtain intrinsic mode function components, calculating a kurtosis-permutation entropy index of the intrinsic mode function components, selecting the intrinsic mode function component with the highest value as an optimal mode component, extracting initial traveling wave arrival time by combining a symmetric differential energy operator, executing a second-layer PSO, and obtaining a second-layer PSO; correcting the initial traveling wave arrival time through a physical constraint optimization model, and adjusting the traveling wave velocity by adopting a self-adaptive wave velocity estimation strategy to obtain the corrected traveling wave head time and traveling wave velocity; and calculating the position of the fault point based on the corrected traveling wave head time and traveling wave velocity. According to the invention, rapid and accurate positioning of fault points is realized, and the robustness is high.

The invention discloses an ant colony optimization energy focusing cable insulation damage positioning method and device, and relates to the technical field of cable detection engineering, and the method comprises the steps: generating a Gaussian envelope linear frequency modulation chirp detection signal, injecting the detection signal into a to-be-detected cable, and collecting an incident signal and an echo signal containing a reflection component; constructing a parameterized time-frequency analysis kernel function family under a Cohen type time-frequency distribution framework, and searching and optimizing kernel parameters by using an ant colony optimization algorithm; and calculating the time frequency distribution and energy-time curve of the signal based on the energy focusing time frequency analysis kernel function obtained through optimization, extracting the arrival time corresponding to an energy peak value, and realizing cable insulation damage positioning according to the reflection time delay and the propagation wave velocity. According to the method, energy peak focusing and peak position stability are enhanced while cross terms are restrained, defect positioning precision and robustness are remarkably improved, and the method is suitable for engineering online detection and automatic implementation of cable insulation damage.