211 results about "Cable fault location" patented technology

The invention provides a distribution line fault location optimization method based on single-ended traveling wave location, and relates to the technical field of traveling wave detection. The method comprises the following steps: carrying out segmented modeling on a line, calculating the traveling wave propagation speed and wave impedance of each segment, and correcting the traveling wave propagation speed and wave impedance; collecting a voltage / current traveling wave signal of a detection point, and extracting a line mode component; performing wavelet transformation on the line mode component, detecting the wave head position of the initial traveling wave through a modulus maximum search algorithm, and recording the arrival time of the initial traveling wave, a corresponding first energy value and polarity; calculating a reflected wave time window based on segmented modeling parameters, screening reversed polarity waves with qualified energy attenuation, and calculating a fault distance; if no effective reflected wave is detected in the reflected wave time window, triggering a pseudo double-end mode; a result is verified through quadruple constraints; the problems of poor parameter adaptability, low signal processing precision, strong reflected wave dependence and incomplete verification in traveling wave distance measurement of a complex distribution line are solved, and the accuracy and reliability of fault distance measurement are improved.

The invention provides a power line fault distance measurement system and method, and belongs to the technical field of power line detection. The system comprises monitoring terminals deployed at two ends of a line and a background processing system, and each monitoring terminal comprises a sensor module used for detecting a traveling wave current signal related to a power line fault in the line; the data acquisition module is used for extracting the arrival time of a traveling wave head according to the detected traveling wave current signal; the GPS time synchronization module is used for adjusting the local clock of the data acquisition module, reducing the time synchronization error of the two monitoring terminals and correcting the arrival time of the traveling wave head; and the background processing system is used for calculating a traveling wave time difference and a junction wave velocity normalization processing result according to the corrected arrival time at the two ends of the line, and determining a fault position coordinate and a fault type. According to the invention, collaborative optimization of fault positioning precision and type identification in a hybrid power line environment is realized.

The invention relates to the technical field of cable asset management and fault prediction, and discloses a cable fault positioning method based on deep learning clustering analysis test waveform characteristics, and the method comprises the steps: collecting waveform and environment data in a cable operation period, and constructing a historical feature library comprising waveform, environment and position features; a self-adaptive detection model is adopted, and parameters are dynamically adjusted to adapt to different working conditions; multi-dimensional feature fusion and matching analysis are combined; a fault point distance is calculated through a signal propagation model and a time difference positioning algorithm, precise positioning is realized by fusing environment compensation and multi-point cross validation, and a three-dimensional geographic coordinate is generated by combining a laying path; and after multiple verifications, a structured report containing a fault type, a risk level, a prediction position, confidence and operation and maintenance suggestions is generated. According to the system, intelligent monitoring, fault risk prediction, asset optimization management and operation and maintenance decision support of a cable operation state are realized, and scientificity and economy of cable management in a complex environment are improved.

The invention discloses a power distribution network three-core cable fault distance measurement analysis method and system, and relates to the technical field of fault distance measurement, and the key points of the technical scheme are that the method comprises the steps: carrying out the empirical mode decomposition of three-phase voltage and current signals; generating a dynamic correction wave velocity based on the cable type, the environment temperature and the soil humidity parameter; determining the first arrival time of the wave head of the initial traveling wave according to the instantaneous frequency abrupt change point of the alpha-mode component, screening the second arrival time of the first reflected wave by using the amplitude gradient of the zero-mode component, and calculating the arrival time difference; and calculating an initial fault distance, and calling the impedance matrix to iteratively correct the initial fault distance. According to the method, the dynamic wave velocity is coupled with multiple factors, the limitation of single parameter correction is broken through, and the problem of transient drift of the wave velocity is solved; and the STFT high-frequency resolution and the wavelet low-frequency stability are fused, and the ridge continuity is optimized in combination with dynamic programming, so that the traveling wave head detection precision can be improved.

An improved HHT algorithm-based cable fault location method and system for a distribution network. The method comprises: as both the voltage and the current of a traveling wave generated by a fault point and reaching a measurement end will sharply change and thus the wave front of the traveling wave will exhibit in a time-frequency graph a high-frequency leap, a leap point being the arrival time of the wave front, separately performing EEMD on line mode components of the double-end traveling wave to extract respective IMF components to be subjected to Hilbert transform, thereby obtaining the instantaneous frequency thereof, the first frequency leap point in the time-frequency graph thereof corresponding to the arrival time of the wave front of a respective fault traveling wave, and then performing fault location by means of a double-end fault location algorithm. The method and system overcome the shortcoming that single moduli of traditional transform matrices fail to reflect all fault types, and solve the problem that traditional EMD algorithms are prone to mode mixing and thus lead to bad accuracy of calibrating wave front signals of travelling waves and not high fault location precision.

The invention relates to the field of cable fault detection, in particular to a distribution cable fault positioning method based on electric signal analysis, which comprises the following steps of: determining a cable analysis state of each abnormal response point according to an interval monitoring execution index; determining whether to perform initial interference analysis or execute evaluation analysis according to the cable analysis state of the abnormal response point location; when initial interference analysis is carried out, whether interference compensation processing and range optimization processing are carried out on each abnormal response point location or not is determined according to the reference feature matching index; determining whether to perform channel filtering or not according to the interference effect evaluation index, and determining whether to perform compensation acquisition processing on each cable monitoring interval or not according to the interference compensation coefficient; and when the execution evaluation analysis is carried out, determining whether to carry out redundancy distribution prompt for each abnormal response point location according to the execution redundancy parameters. According to the method, the cable fault positioning efficiency is guaranteed, and meanwhile, the requirement for monitoring point arrangement is lowered.

The invention provides an optical cable fault positioning method based on OTDR signal characteristic adaptive denoising and event identification, and the method comprises the steps: classifying modal components after OTDR signal adaptive noise decomposition based on a preset entropy threshold value, and obtaining a noise dominant component, a mixed component and a signal dominant component; singular value difference spectrum abrupt change point detection is carried out on the noise dominant component, and residual useful signals are extracted; verifying the entropy value of the mixed component, and reconstructing the component meeting the entropy threshold value, the signal dominant component and the residual useful signal into a de-noised signal; synchronously optimizing hyper-parameters and feature selection subsets of the support vector machine by adopting a swarm intelligence algorithm, wherein search parameters of the algorithm are dynamically updated according to an exponential decay mechanism; and outputting fault point space position information based on the optimized support vector machine model.

The invention discloses a cable operation state fault rapid detection method based on an improved grey wolf algorithm model. The method comprises the following steps: collecting fault data through a detection unit; cleaning, denoising, normalization processing and feature extraction are carried out on the collected fault data; constructing an improved grey wolf algorithm model, wherein the improved grey wolf algorithm model comprises a coding module, an adaptive weight adjustment module, a multi-objective optimization module, a population diversity control module and an optimal path search module; fault detection is carried out on the cable operation state data through a global search module and a local search module; real-time monitoring and early warning are carried out, wherein the real-time monitoring and early warning comprise early warning threshold setting, early warning signal triggering, early warning notification and feedback optimization; according to the invention, the operation state fault of the cable is detected through the improved grey wolf algorithm model, and the detection efficiency and the accuracy of cable fault positioning are greatly improved.

The invention relates to the technical field of cable fault positioning, in particular to a cable fault accurate positioning method based on multi-channel synchronous acquisition, which comprises the following steps: S1, constructing a multi-channel adaptive acquisition system which comprises a main controller, a multi-channel acquisition module, a synchronous control module and a data transmission module; s2, multi-channel data synchronous acquisition is carried out through the synchronous control module, wherein the multi-channel data comprises impedance data, temperature data, partial discharge signals and insulation resistance data; during use, through a multi-channel adaptive acquisition design, monitoring channels can be flexibly selected according to cable materials, operation years and environmental conditions, different aging fault characteristics are comprehensively covered, the fault omission ratio and the false alarm rate are reduced, different types of low-voltage cables are adapted, a synchronous scheme of constant-temperature crystal oscillator and hardware triggering is adopted, and the reliability of the system is improved. The method does not need to depend on a GPS / PTP time service module, is favorable for saving cost input, and eliminates environmental interference and single parameter false triggering.

The invention provides a fault signal detection system and an analysis positioning method, and relates to the technical field of signal detection. An injection module is used for periodically applying narrowband acoustic disturbance capable of adaptively selecting frequency and power to an optical cable sheath; the passive wireless label nodes arranged along the line collect multi-dimensional data such as arrival timestamps, amplitudes, frequencies, phases, local temperatures and the like in real time, and upload the data through near-field coupling. And the convergence module completes node identification association and batch aggregation, the analysis and construction module constructs an acoustic propagation path map, and after temperature difference segmentation compensation, an actual laying path is dynamically recovered by adopting a map search algorithm. And the projection and identification module maps the map to a geographic information system coordinate system and outputs a fault space position, thereby realizing real-time and accurate optical cable fault positioning under a topology-free prior condition, remarkably reducing manual inspection and misjudgment rates, and being suitable for a multi-branch and multi-repair long-distance communication or power optical cable scene.

The invention is suitable for the technical field of fault distance measurement, and provides a power distribution network fault distance measurement method and system based on fault point voltage transient waveform comparison, and the method comprises the steps: collecting three-phase voltage and current signals at two ends of a line when a power distribution network fault occurs, and extracting a transient component signal in a preset frequency range; performing phase-mode transformation decoupling processing on the transient component signal; constructing a transient voltage differential equation from the two ends of the line to a hypothetical fault point, dynamically adjusting the fault position hypothetical point in a preset distance measurement interval by adopting a dichotomy, and calculating a transient voltage calculation waveform from the two ends of the line to the fault position hypothetical point; performing time domain similarity analysis on the transient voltage calculation waveform, and calculating a waveform consistency index; judging whether a preset convergence condition is met or not; if yes, determining that the current fault position hypothesis point is a target fault point; otherwise, adjusting the dichotomy interval according to the waveform comparison difference direction, and carrying out the next round of iterative calculation until the convergence condition is met, thereby effectively improving the fault distance measurement accuracy.

The invention, which belongs to the technical field of fault detection, discloses a fault distance measurement and fault positioning system for a distributed power line, comprising a line signal state analysis module, a line signal adjustment module, a line communication interference determination module and a line fault distance measurement and positioning result output module. According to the method, the accuracy of the input signal is judged by analyzing the characteristics of the abnormal signal, so that the signal is adjusted, the accuracy of the input signal of the ranging and positioning system is improved, the problem that the accuracy of the input signal is neglected in the prior art is effectively solved, the system can accurately and quickly carry out ranging and positioning on a fault, and the working efficiency is improved. Losses caused by wrong positioning faults are reduced, and power supply reliability and stability are improved.

The invention discloses a traveling wave triggering constant value adjusting method and device, a storage medium and computer equipment, relates to the technical field of traveling wave fault distance measurement, and mainly aims to solve the problem that key fault feature information of a power transmission line is lost due to a fixed triggering constant value of a non-contact traveling wave positioning device on a distributed monitoring node in the prior art. Comprising the steps of obtaining a power transmission line topological graph and a constant value list, and determining a double-end substation constant value line table corresponding to a to-be-adjusted power transmission line based on the constant value list and installation point position information in the power transmission line topological graph; when an initial instantaneous fault occurs, acquiring a traveling wave amplitude reported by each non-contact traveling wave positioning device on the to-be-adjusted power transmission line; determining a fault point interval position on the to-be-adjusted power transmission line based on the traveling wave amplitude and a double-end transformer substation constant value line table; and determining a triggering constant value of the to-be-adjusted non-contact traveling wave positioning device on the to-be-adjusted power transmission line according to the fault point interval position and the double-end transformer substation constant value line table.

The invention relates to a hybrid line fault location method and device based on traveling wave location, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: acquiring the total length of a target power line in a power topological structure; calculating to obtain a theoretical wave velocity rated value of each cable section; according to a preset time interval, obtaining a temperature measurement result, calculating to obtain a theoretical wave velocity real-time value of each cable section, carrying out normalization processing on the theoretical wave velocity real-time value of each cable section, and converting the theoretical wave velocity real-time value into a wave velocity of an equivalent overhead line section; under the condition that a line fault occurs, the wave head signal time difference of a fault wave is obtained through the two traveling wave measurement terminals; and determining a theoretical fault position according to the wave velocity and the wave head signal time difference of the equivalent overhead line section. By adopting the method, the fault point measurement accuracy of the mixed line of the overhead line and the cable can be improved under the condition of controlling the cost.

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 application discloses a submarine cable path detection device and method and a cable fault positioning method, and the detection device comprises a detection ship, a general control module, a rudder control module, a positioning and information transmission system, a cable path detection assembly, a fault detection assembly and a land centralized control center. The application applies low-frequency voltage to the fault of the submarine cable, so that an alternating magnetic field is generated in the sea area around the cable, and the trend of the submarine cable is detected and judged, the technical defects that the submarine cable is inconvenient to maintain when the actual line deviates from the original laid line are overcome, time is saved, and efficiency is improved. The cable fault positioning method of the application quickly positions the fault point, overcomes the problems that the previous determination of the submarine cable fault point is time-consuming and labor-consuming, and the positioning accuracy of the fault point is not high, and improves the positioning accuracy and efficiency of the fault point.

The invention discloses a power cable outer sheath fault positioning method, and belongs to the technical field of cable fault positioning. Aiming at the problems of poor adaptability, weak anti-interference capability and low positioning precision of the existing cable outer sheath fault positioning technology, the method comprises the following steps of: acquiring horizontal and vertical components of an electromagnetic signal by deploying an array sensor, and obtaining pure vector distribution through Fourier transform and wavelet denoising processing; judging coordinates of an abnormal point according to an amplitude threshold value and a phase ratio, and determining a fault cluster center by adopting K-means clustering; and fusing the environmental data, refining the position through iterative filtering, comparing and confirming a final fault point in combination with triangulation and historical data, and generating a vector distribution map and a diagnosis report. According to the invention, high-precision and anti-interference positioning and visual diagnosis of cable faults in a complex environment are realized.

The invention belongs to the technical field of power distribution network fault positioning, and provides a cable type power distribution network fault classification and positioning method, which comprises the steps of identifying a three-core cable structure and electrical parameters, constructing a normal and fault state model, generating a fault identification signal by using a power electronic switch combination of an additional power supply, and detecting a fault type. And obtaining short-circuit current data through phase-mode conversion, and calculating a fault distance by adopting a harmonic impedance method. According to the invention, the multi-frequency harmonic injection and power electronic switch combination technology is utilized to enhance the weak fault current detection capability; a phase-mode transformation method for expanding a Karenbauer matrix is adopted, and electromagnetic coupling interference between the guide core and the shielding layer is eliminated; a harmonic impedance fault distance measurement method reduces the distance measurement error; localized fault positioning is achieved through fast Fourier transform, and dependence on a remote monitoring system is reduced. According to the invention, high-precision, strong-disturbance-rejection and fast-response power distribution network fault positioning is realized, and an efficient technical scheme is provided for reliable operation of the intelligent power distribution network.

The invention discloses a cable fault positioning method, device and equipment and a storage medium, and relates to the technical field of fault positioning. The method comprises the following steps: acquiring impedance data of a to-be-detected cable; chirp-Z transformation is carried out on the impedance data to obtain positioning spectrum data, the positioning spectrum data comprises a corresponding relation between a normalized amplitude and a target distance, and the target distance is the distance from an acquisition point of the impedance data; and determining the fault position of the to-be-detected cable according to the positioning spectrum data. According to the technical scheme provided by the embodiment of the invention, the impedance data is processed by utilizing Chirp-Z transformation, the accurate positioning spectrum data with higher resolution, fewer interference peaks and low data redundancy are obtained, and the positioning of various cable faults can be realized according to the corresponding relationship in the positioning spectrum data.

A time-domain distance protection method and system resistant to the impact of transition resistance. The used technical solution is: using voltage and current sampling sequences at a protection installation position to construct a time-domain equation, adjusting a zero-sequence current angle on the basis of system-related parameters, and solving a fault location and transition resistance; and determining whether a calculated fault distance is smaller than a preset value, and using same as a condition for triggering the action of protection. Therefore, the problem of time-domain distance protection overreaching caused by transition resistance is solved, thereby improving the applicability of distance protection of power transmission lines.

The invention provides a magnetic field traveling wave signal processing method for cable fault detection and related equipment, and relates to the technical field of cable fault detection, and the method comprises the steps: configuring a distributed sensor according to an identified key position of a cable, and collecting a magnetic field traveling wave signal of the cable through the distributed sensor, and obtaining a time sequence signal data set; performing preprocessing and signal enhancement on the time sequence signal data set in sequence, and inputting signal features of the time sequence signal data set after signal enhancement into a pre-optimized fault identification model to obtain a fault positioning result of the cable; wherein the fault identification model is obtained by performing model parameter optimization by adopting a pre-established multi-objective function based on a particle swarm and a preset particle search strategy, and the particle search strategy is set according to a preset speed updating mechanism and a current noise interference state. Therefore, the method effectively enhances the accuracy and practicability of the fault detection system while improving the quality of the cable fault signal.

According to the cable fault positioning system based on multi-detection node data fusion, integration of early warning and accurate positioning of cable faults is achieved through multi-node cooperative monitoring and data fusion, a partial discharge feature recognition and pulse reflection joint detection mechanism is adopted, a signal propagation speed compensation model and a multi-source data optimization algorithm are combined, and the cable fault positioning accuracy is improved. The limitation of a single detection node is effectively overcome, the accuracy and reliability of fault positioning are remarkably improved, and the fault finding time and the power failure loss are reduced.

The invention discloses a fault location method and system for a multi-terminal hybrid line, and the method comprises the steps: obtaining traveling wave data in real time based on a traveling wave collection equipment deployment scheme, and carrying out the preprocessing, and obtaining the processed traveling wave data; processing the processed traveling wave data based on multi-mode processing, and determining a fault initial traveling wave and a moment set corresponding to the fault initial traveling wave; obtaining an initial traveling wave velocity from a database and correcting the initial traveling wave velocity to obtain a corrected traveling wave velocity; processing the processed traveling wave data based on multi-mode processing, and determining a fault initial traveling wave and a moment set corresponding to the fault initial traveling wave; and correcting the initial distance to obtain a final distance from the fault point to one end of the line, thereby solving the problems of low distance measurement precision and difficulty in accurately positioning the position of the fault point caused by difficulty in distance measurement by combining various types of data in the existing multi-end mixed line fault distance measurement method.

The invention discloses a channel environment measured data traveling wave fault distance measurement method, which belongs to the technical field of channel environment traveling wave fault distance measurement, and comprises the following steps of: 1, screening traveling wave fault recording data; step 2, calibrating a traveling wave head; step 3, carrying out power transmission line traveling wave fault distance measurement; and step 4, optimizing the traveling wave distance measurement device. According to the method, fractal dimensions and transient energy are used as feature vectors, a small number of known category historical samples are introduced as prompts, partial supervision clustering is formed, the fault membership degree of weak faults is improved, and blindness of clustering number and initial value selection is avoided. The continuity of a single fault event action and the tightness in time are considered, the time neighborhood constraint is added in the clustering process, and the detection capability of small-fault-angle faults and high-resistance faults far away from a clustering center recognition sample is enhanced. Interference waves are eliminated according to the length and slope characteristics, and reliable calibration of the wave head is achieved.

The present invention discloses an intelligent cable fault location system for an integrated utility tunnel, which relates to the technical field of cable fault location. The system includes a flaw detection module, an environmental monitoring module, a cable performance information acquisition module, a first neural network model module, a model update module, and a cable fault intelligent prediction module. By setting up the flaw detection module, the environmental monitoring module, the cable performance information acquisition module, the first neural network model module, the model update module, and the cable fault intelligent prediction module, the intelligent cable fault location system for the integrated utility tunnel can analyze the influence of historical environmental change amounts on mechanical damage, thereby analyzing the cable loss rate according to the environmental change amounts. When the predicted cable predicted loss rate is less than the set first loss rate threshold, the cable in the corresponding area is actively detected again, and the cable loss rate prediction model is trained and updated by using the newly added active detection data to ensure the accuracy of the model.

The invention discloses a graphical fault distance measurement method and system, relates to the field of traction substation tripping fault mark distance measurement in the railway industry, and can read a fault report of a fault distance measurement device and constant value parameter configuration of the fault distance measurement device off line, and calculate and analyze a fault type, whether line current is balanced or not and a fault distance according to the data and parameters. And a result is graphically displayed, so that the distance measurement error range can be narrowed by modifying and verifying the constant value parameters, and the corrected constant value parameters are exported and stored, thereby achieving the purposes of facilitating fault analysis, improving the working efficiency and shortening the maintenance time. Maintenance personnel are helped to quickly find out fault points, timely process faults and recover normal operation of lines, and the method is very important for safe, reliable and efficient transportation of a railway system.

The application relates to a positioning method of a cable fault positioning device based on electromagnetic method, which comprises the following steps: step S1: detecting a metal pipeline through a magnetic field to obtain a cable path; step S2: obtaining electrical characteristic data of each cable joint, and judging which two joints the fault occurs between based on historical data of each cable joint; and step S3: obtaining fault characteristic data to position the fault according to the two joints obtained in step S2. In an offline state, the application can position the position of a fault cable joint by observing characteristic values of the joint through an equal proportionally reduced voltage and current signal, so that the fault point can be further given in detail.

The invention discloses a railway traction network fault distance measurement visual monitoring method and device. The method comprises the following steps: acquiring power supply arm information and fault information; constructing a basic block diagram of a fault analysis chart corresponding to the power supply arm, and marking switch information included in the power supply arm information and the fault information in the fault analysis chart; performing fault distance analysis according to the fault information and the power supply arm information to obtain a fault analysis result; and positioning a fault display position in the fault analysis chart according to a fault analysis result, and marking the fault display position in the fault analysis chart. Through visual drawing of a fault analysis result, a switch state and a fault display position can be visually seen in a drawn fault analysis chart, and monitoring personnel are helped to visually understand a fault distance.

The application discloses a kind of wide frequency impedance spectrum cable fault location methods based on end function compensation, comprising: according to the equivalent model of micro-unit of healthy coaxial cable, the voltage current partial differential equation set of healthy coaxial cable is determined, and its general solution is calculated;According to general solution, the reflection coefficient of healthy coaxial cable load end is calculated, and according to the reflection coefficient and general solution, the impedance spectrum of healthy coaxial cable about frequency is calculated;The impedance spectrum about frequency of measured cable is measured, and difference comparison is carried out with the impedance spectrum of healthy coaxial cable, to determine whether the measured cable exists fault;According to phase spectrum, construct orthogonal integral function, introduce gauss filter to eliminate the interference of local big fault, and extract the extreme value and maximum value of function, form compensation function;Establish fault diagnosis function based on impedance phase spectrum, determine the local fault position and local soft fault type of measured cable, realize accurate positioning of different fault positions, and greatly improve the detection and positioning precision for traditional method.

The application discloses a power distribution network phase-to-phase short-circuit fault distance measurement method, equipment and medium, wherein the method comprises the following steps: sampling and acquiring each-phase voltage at the head of a protection section, and judging whether the starting criterion is met according to the acquired voltage; if yes, starting the fault distance measurement method, and the distributed power supply injects a high-frequency current detection signal into the line; sampling and acquiring three-phase voltage and current of one power frequency cycle before and after the fault at the head of the protection section; extracting power frequency component and high-order harmonic component of each-phase voltage and current by using a fast Fourier algorithm, and calculating the power frequency fault component; judging the fault type and the fault phase by using the difference between the power frequency current fault components of each two phases; obtaining the fault distance measurement equation according to the fault type, solving the fault distance measurement equation, and obtaining the fault distance. The application solves the problem of the fault distance measurement of the power distribution network phase-to-phase short-circuit fault containing the distributed power supply, and does not need to additionally install a signal injection device. The application can be widely applied in the field of power distribution network fault positioning.