Dual-end monitoring-based partial discharge source localization method and system for high-frequency partial discharge of high-voltage cable

Abstract

Disclosed in the present invention are a dual-end monitoring-based partial discharge source localization method and system for high-frequency partial discharge of a high-voltage cable. The method comprises: acquiring operation data and phase velocity test data of a high-voltage cable; when a partial discharge fault occurs in the high-voltage cable, collecting partial discharge signals on two sides of the high-voltage cable by means of sensors on the two sides of the high-voltage cable; performing Fourier transform respectively on the basis of the partial discharge signals on the two sides to obtain amplitude-frequency characteristics of the partial discharge signals, and preprocessing the collected partial discharge signals on the basis of the amplitude-frequency characteristics to optimize and improve a phase difference algorithm; and by incorporating the phase velocity test data of the high-voltage cable, using the improved phase difference algorithm to perform partial discharge source localization on the faulty cable. In the present invention, dual-end monitoring is used to reduce the attenuation of signals caused by long-distance transmission, and synchronization of two sensors is performed using a PTP protocol, effectively reducing errors; and in addition, during monitoring, partial discharge source localization is performed using the improved phase difference algorithm, which is conducive to resisting external interference, and there is no need to determine the time of arrival, greatly improving the positioning accuracy.

Description

A high-frequency partial discharge double-end monitoring partial discharge source positioning method and system for high-voltage cables TECHNICAL FIELD

[0001] The present application relates to the technical field of cable fault monitoring, and in particular to a high-frequency partial discharge double-end monitoring partial discharge source positioning method and system for high-voltage cables. BACKGROUND

[0002] Cable partial discharge refers to the phenomenon that electrical energy is released due to electrical breakdown at a local part of a cable caused by defects or damage inside the equipment, excessively high voltage, or differences in electric field intensity, etc. in the electrical equipment. High-voltage cable partial discharge is a relatively common fault. However, the length of the cable is relatively long, and it is impossible to check one by one, so a high-frequency partial discharge source positioning method for high-voltage cables is needed for positioning. The existing source positioning method is relatively comprehensive, but still has certain defects.

[0003] Firstly, in order to save monitoring costs, the existing monitoring method mostly adopts a single-end monitoring method, that is, a monitoring sensor is installed at one end of the cable, the time difference between the direct time and the reflected time of the pulse signal at the partial discharge position is monitored, and the position of the partial discharge is calculated according to the formula. By using this method for monitoring, the transmission distance of the pulse signal is long, resulting in large loss, which greatly increases the accuracy of the monitoring, so the double-end monitoring method is used for monitoring. When double-end monitoring is performed, time synchronization of the two-end monitoring sensors is needed. The existing method uses GPS to realize time synchronization of the two-end sensors, which has the problem of large error. In addition, in the process of partial discharge monitoring, the sampling rate of the equipment, the phase speed frequency variation effect and the environment have a great influence on the monitoring result, which greatly reduces the accuracy of the monitoring.

[0004] SUMMARY

[0005] This section aims to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification of the present application in order to avoid obscuring the purpose of this section, the abstract and the title, and such simplifications or omissions cannot be used to limit the scope of the present application.

[0006] In view of the above-mentioned existing problems, the present application is proposed.

[0007] Therefore, the present application provides a high-frequency partial discharge double-end monitoring partial discharge source positioning method and system for high-voltage cables to solve the problems mentioned in the background art.

[0008] To solve the above technical problems, the present application provides the following technical solutions:

[0009] In a first aspect, an embodiment of the present application provides a partial discharge source positioning method for high-frequency partial discharge double-end monitoring of a high-voltage cable, comprising: obtaining operation data and phase velocity test data of the high-voltage cable;

[0010] judging whether the high-voltage cable has a partial discharge fault based on the operation data, and if the high-voltage cable has a partial discharge fault, collecting partial discharge signals on both sides of the high-voltage cable through sensors on both sides of the high-voltage cable;

[0011] performing Fourier transform on the partial discharge signals on both sides to obtain amplitude-frequency characteristics of the partial discharge signals, and pre-processing the collected partial discharge signals according to the amplitude-frequency characteristics to optimize and improve a phase difference algorithm;

[0012] combining the phase velocity test data of the high-voltage cable, and positioning a partial discharge source of a fault cable by using the improved phase difference algorithm.

[0013] As a preferred scheme of the partial discharge source positioning method for high-frequency partial discharge double-end monitoring of a high-voltage cable, the phase velocity test data comprises phase velocity data when the high-voltage cable is shut down;

[0014] The test data is obtained by using a time domain method and a frequency domain method based on parameters of the high-voltage cable, and a phase velocity value is calculated based on a test result and a phase velocity database is established;

[0015] The calculation of the phase velocity value is represented as:

[0016] wherein f is a frequency, μ0 is a vacuum permeability, μ r is a relative permeability of the high-voltage cable, ε0 is a vacuum permittivity, ε r is a relative permittivity of the high-voltage cable, σ is an electrical conductivity of the high-voltage cable, and ω is an angular frequency and ω=2πf.

[0017] As a preferred scheme of the partial discharge source positioning method for high-frequency partial discharge double-end monitoring of a high-voltage cable, judging whether the high-voltage cable has a partial discharge fault based on the operation data comprises:

[0018] integrating operation data of different modes into unified features, performing feature fusion on the operation data of the high-voltage cable, and constructing a high-voltage cable state perception network;

[0019] detecting and extracting features of partial discharge activity characteristics through the high-voltage cable state perception network, and when monitored partial discharge parameters exceed a preset fault threshold, the high-voltage cable has a partial discharge fault, otherwise the high-voltage cable is in normal operation.

[0020] As a preferred scheme of the high-frequency partial discharge double-end monitoring partial discharge source positioning method of the high-voltage cable of the application, wherein: when there is a partial discharge fault, the partial discharge signals on both sides of the high-voltage cable are collected by the sensors on both sides of the high-voltage cable, including: the sensors on both sides of the high-voltage cable monitor the partial discharge signals on both ends of the high-voltage cable in real time; the sensors on both sides are also time-synchronized by the PTP protocol, and the monitored partial discharge signals are uploaded to the upper layer network.

[0021] As a preferred scheme of the high-frequency partial discharge double-end monitoring partial discharge source positioning method of the high-voltage cable of the application, wherein: the PTP protocol time synchronization method includes: defining any sensor on one side of the high-voltage cable as a first sensor, and the other side as a second sensor;

[0022] The first sensor sends the partial discharge signals collected by each monitoring node synchronously at the local t1 time, and saves t1 time to the time synchronization request packet and sends it to the second sensor;

[0023] When the second sensor receives the partial discharge signals collected by each monitoring node synchronously, the local receiving time t2 is recorded; when the second sensor receives the time synchronization request packet, the t1 time in the time synchronization request packet is saved;

[0024] The second sensor sends a delay request to the first sensor, and records the sending time t3 locally;

[0025] When the first sensor responds to the delay request of the second sensor, the receiving time t4 is recorded, and t4 time is sent to the second sensor through the feedback communication link;

[0026] The second sensor receives the data and saves t4 time, and after receiving t4 time, the high-voltage cable side with the second sensor collects the timestamp information t1, t2, t3, t4 locally;

[0027] Calculate the time offset of the second sensor and the first sensor to complete the time synchronization of the partial discharge signals on both sides of the high-voltage cable.

[0028] As a preferred scheme of the high-frequency partial discharge double-end monitoring partial discharge source positioning method of the high-voltage cable of the application, wherein: based on the partial discharge signals on both sides, the amplitude-frequency characteristics of the partial discharge signals are obtained by Fourier transform, and the pre-processing and optimization of the phase difference algorithm of the collected partial discharge signals according to the amplitude-frequency characteristics include: the time-synchronized partial discharge signals are mathematically simulated in the form of double-exponential decay and double-exponential decay oscillation pulse;

[0029] In the partial discharge signal waveform, Gaussian white noise with a signal-to-noise ratio of 20 dB is superimposed, the waveform is analyzed and positioned, and the direct wave and the reflected wave are separated and processed, the amplitude-frequency characteristic curve of the direct wave and the reflected wave is obtained by using Fourier transform, and the optimized and improved phase difference algorithm is obtained by Monte Carlo simulation.

[0030] As a preferred scheme of the high-frequency partial discharge double-end monitoring partial discharge source positioning method of the high-voltage cable, wherein: the improved phase difference algorithm is used for positioning the partial discharge source of the fault cable in combination with the phase velocity test data of the high-voltage cable, including: replacing different types of cables to collect partial discharge signals; and the position of the partial discharge source is obtained by comparing the phase velocity test data of the high-voltage cable with the phase difference of the collected actual partial discharge signals.

[0031] In a second aspect, the present application provides a high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning system, comprising: a data acquisition module for acquiring operation data and phase velocity test data of a high-voltage cable;

[0032] A judgment module is configured to determine whether the high-voltage cable has a partial discharge fault based on the operation data, and if there is a partial discharge fault, then through the sensors on both sides of the high-voltage cable, partial discharge signals on both sides of the high-voltage cable are collected.

[0033] An optimization module is configured to perform Fourier transform on the partial discharge signals on both sides respectively to obtain the amplitude-frequency characteristics of the partial discharge signals, and to optimize and improve the phase difference algorithm based on the amplitude-frequency characteristics and the collected partial discharge signals.

[0034] A positioning module is configured to use the improved phase difference algorithm to position the partial discharge source of the fault cable in combination with the phase velocity test data of the high-voltage cable.

[0035] In a third aspect, the present application provides a computing device, comprising:

[0036] a memory and a processor;

[0037] The memory is configured to store computer executable instructions, and the processor is configured to execute the computer executable instructions, so as to realize the steps of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method.

[0038] In a fourth aspect, the present application provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions are executed by a processor to realize the steps of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method.

[0039] Compared with the prior art, the present application has the beneficial effects that: the present application adopts the technology of double-end monitoring, simultaneously monitors two ends of the high-frequency partial discharge source of the high-voltage cable through two sensors, reduces the attenuation caused by long-distance signal transmission, simultaneously utilizes the PTP protocol to synchronize the two sensors, effectively reduces the error, and adopts the improved phase difference algorithm for partial discharge source positioning during monitoring, is beneficial to resisting external interference, simultaneously does not need to determine the time of arrival, and greatly improves the positioning accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0041] Fig. 1 is a method flowchart of the high-frequency partial discharge double-end monitoring partial discharge source positioning method and system of the high-voltage cable according to an embodiment of the present application;

[0042] Fig. 2 is an internal structure diagram of the computer equipment of the high-frequency partial discharge double-end monitoring partial discharge source positioning method and system of the high-voltage cable according to an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings in the specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the protection scope of the present application.

[0044] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0045] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is the embodiment alone or selectively excluded from other embodiments.

[0046] The application is described in detail in combination with the schematic diagram. In the detailed description of the embodiments of the application, the cross-sectional view of the device structure is partially enlarged without the general proportion for the convenience of illustration, and the schematic diagram is only an example, which should not limit the scope of protection of the application herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual production.

[0047] Meanwhile, in the description of the application, it should be noted that the terms "upper, lower, inner and outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. In addition, the terms "first, second or third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] Unless otherwise specifically defined and limited in the application, the terms "mounting, connecting, connecting" should be broadly understood, for example: it can be fixedly connected, detachably connected or integrally connected; it can also be mechanically connected, electrically connected or directly connected, it can also be indirectly connected through an intermediate medium, or it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0049] Embodiment 1

[0050] Referring to FIGS. 1-2, one embodiment of the application provides a high-frequency partial discharge double-end monitoring partial discharge source positioning method for high-voltage cables, comprising:

[0051] S1: obtaining the operation data of the high-voltage cable and the phase velocity test data;

[0052] Further, the obtained operation data of the high-voltage cable includes but is not limited to partial discharge monitoring data such as UHF, AE, TEV, ultrasonic wave, etc.; temperature monitoring data, stress monitoring data, vibration monitoring data, video monitoring data, power system operation data such as voltage, current, power, load, etc., environmental data such as humidity, air pressure, wind speed, rainfall, etc.

[0053] Further, the phase velocity test data includes: testing the phase velocity data of the high-voltage cable when it is stopped;

[0054] The test is based on the parameters of the high-voltage cable, and the time domain method and the frequency domain method are used to obtain the test data, and the phase velocity value is calculated based on the test results and a phase velocity database is established;

[0055] The calculation of the phase velocity value is represented as:

[0056] where f is the frequency, μ0is the vacuum permeability, μ r is the relative permeability of the high-voltage cable, ε0is the vacuum permittivity, ε r is the relative permittivity of the high-voltage cable, σ is the conductivity of the high-voltage cable, ω is the angular frequency and ω = 2πf.

[0057] It should be noted that at a given frequency f, the phase velocity of electromagnetic waves in the high-voltage cable can be calculated by the phase constant β(f). After obtaining the test data by time domain and frequency domain methods, the specific phase velocity value is calculated according to the formula, and these data are saved in the database for subsequent cable state evaluation, fault diagnosis or other research and analysis. The phase velocity test and its data analysis help to understand the electrical characteristics of the cable medium, identify potential faults or abnormalities, and evaluate the performance of the cable at different frequencies. The phase constant contains the influence of inductance (related to magnetic permeability), capacitance (related to dielectric constant) and loss (related to conductivity) of the cable medium on electromagnetic wave propagation. It is dimensionless, with rad / m as the unit, and the phase constant is expressed as:

[0058] S2: judging whether there is a partial discharge fault in the high-voltage cable based on the operation data, if there is a partial discharge fault, collecting the partial discharge signals on both sides of the high-voltage cable through the sensors on both sides of the high-voltage cable;

[0059] Further, judging whether there is a partial discharge fault in the high-voltage cable based on the operation data includes:

[0060] Integrating the operation data of different modalities into a unified feature, performing feature fusion on the operation data of the high-voltage cable, and constructing a high-voltage cable state perception network;

[0061] Detecting and extracting the features of the partial discharge activity characteristics through the high-voltage cable state perception network, when the monitored partial discharge parameters exceed the preset fault threshold, the high-voltage cable has a partial discharge fault, otherwise it is normal.

[0062] It should be noted that before feature fusion, the collected data need to be preprocessed, such as cleaning, denoising, filling missing values, and normalization, to ensure data quality and consistency. Fuse multi-source data to construct a cable state perception network. Feature-level fusion (such as concatenation, weighted sum) or decision-level fusion (such as voting, averaging, stacking) methods can be used to integrate data of different modalities into a unified feature representation.

[0063] Spatio-temporal correlation analysis: using spatio-temporal sequence analysis, dynamic Bayesian network and other methods to reveal the spatio-temporal correlation of partial discharge signals with environmental factors, load changes, seasonal cycles and other multi-dimensional factors, and extract high-level features reflecting these correlations.

[0064] It should be noted that the preset fault threshold in the embodiments of the present application can be dynamically adjusted according to the probability distribution of the real-time monitoring data, and the present application does not make specific limitations.

[0065] In an optional embodiment, in the double-end monitoring process, the test cable can also be charged, and then a damped oscillation voltage wave is generated through loop discharge, partial discharge occurs according to the defect position of the cable, and the sensor is used to monitor the partial discharge signal, wherein the voltage in the high-voltage cable is 22kv, and the sampling frequency of the sensor is 200MHz.

[0066] Further, when there is a partial discharge fault, the partial discharge signals on both sides of the high-voltage cable are collected through sensors on both sides of the high-voltage cable, including that the sensors on both sides of the high-voltage cable monitor the partial discharge signals on both ends of the high-voltage cable in real time; the sensors on both sides also use the PTP protocol for time synchronization, and upload the monitored partial discharge signals to the upper layer network.

[0067] Further, the PTP protocol time synchronization method includes: defining an arbitrary sensor on one side of the high-voltage cable as a first sensor, and the other side as a second sensor;

[0068] The first sensor sends the partial discharge signals collected by each monitoring node synchronously at a local t1 moment, and saves the t1 moment to a time synchronization request packet and sends it to the second sensor;

[0069] When the second sensor receives the partial discharge signals collected synchronously by each monitoring node, the local receiving moment t2 is recorded; when the second sensor receives the time synchronization request packet, the t1 moment in the time synchronization request packet is saved;

[0070] The second sensor sends a delay request to the first sensor, and records the sending moment t3 locally;

[0071] When the first sensor responds to the delay request of the second sensor, the receiving moment t4 is recorded, and the t4 moment is sent to the second sensor through a feedback communication link;

[0072] The second sensor receives the data and saves the t4 moment, and after receiving the t4 moment, the high-voltage cable side with the second sensor has collected the timestamp information t1, t2, t3, t4 locally;

[0073] The time offset of the second sensor and the first sensor is calculated, and the time synchronization of the partial discharge signals on both sides of the high-voltage cable is completed.

[0074] In an optional embodiment, the calculation of the time offset of the second sensor and the first sensor is represented as: T_offset=(t2+t3-t1-t4) / 2

[0075] Wherein, T_offset is the time offset of the second sensor relative to the first sensor, that is, the clock bias that needs to be corrected, t1 is the time reference of the first sensor, t2 is the one-way communication delay between the first sensor and the second sensor. t3 is the time when the second sensor sends a communication request, which is used to calculate the communication round trip time, and t4 is the time when the first sensor receives the communication request, which together with t3 constitutes the communication round trip time.

[0076] S3: Fourier transform the partial discharge signals on both sides to obtain the amplitude-frequency characteristics of the partial discharge signals, and pre-process the collected partial discharge signals according to the amplitude-frequency characteristics to optimize and improve the phase difference algorithm;

[0077] Further, based on the Fourier transform of the partial discharge signals on both sides, the amplitude-frequency characteristics of the partial discharge signals are obtained, and the collected partial discharge signals are pre-processed according to the amplitude-frequency characteristics to optimize and improve the phase difference algorithm, including: the time-synchronized partial discharge signals are mathematically simulated in the form of double exponential decay and double exponential decay oscillation pulse.

[0078] In the partial discharge signal waveform, Gaussian white noise with a signal-to-noise ratio of 20dB is superimposed, the waveform is analyzed and positioned, and the direct wave and reflected wave are separated and processed, the Fourier transform is used to obtain the amplitude-frequency characteristic curve of the direct wave and reflected wave, and the amplitude-frequency characteristic curve is simulated by Monte Carlo to obtain the optimized and improved phase difference algorithm.

[0079] S4: Combined with the phase velocity test data of the high-voltage cable, the improved phase difference algorithm is used to locate the partial discharge source of the fault cable.

[0080] Further, combined with the phase velocity test data of the high-voltage cable, the improved phase difference algorithm is used to locate the partial discharge source of the fault cable, including: replacing different types of cables to collect partial discharge signals; and obtaining the position of the partial discharge source by comparing the phase difference between the high-voltage cable phase velocity test data and the actual partial discharge signals collected.

[0081] It should be noted that, due to the interference noise in the cable, the frequency band needs to be selected, and the selected frequency band is 1-3.43Hz.

[0082] The above is a schematic scheme of the partial discharge source positioning method of the high-voltage cable high-frequency partial discharge double-end monitoring system. It should be noted that the technical scheme of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning system and the technical scheme of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method described above belong to the same concept, and the technical scheme of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning system in this embodiment is not described in detail. The details can be referred to the description of the technical scheme of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method.

[0083] The high-frequency partial discharge double-end monitoring partial discharge source positioning system of the high-voltage cable in the embodiment comprises:

[0084] The data acquisition module is configured to acquire operation data and phase velocity test data of the high-voltage cable.

[0085] The judgment module is configured to judge whether the high-voltage cable has a partial discharge fault based on the operation data, and if the high-voltage cable has the partial discharge fault, collect partial discharge signals on both sides of the high-voltage cable through sensors on both sides of the high-voltage cable.

[0086] The optimization module is configured to respectively perform Fourier transform on the partial discharge signals on both sides to obtain amplitude-frequency characteristics of the partial discharge signals, and pre-process the collected partial discharge signals according to the amplitude-frequency characteristics to improve the phase difference algorithm.

[0087] The positioning module is configured to combine the phase velocity test data of the high-voltage cable, and use the improved phase difference algorithm to position the partial discharge source of the fault cable.

[0088] The embodiment further provides a computing device suitable for the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method, comprising:

[0089] The computing device comprises a memory and a processor, the memory is configured to store computer executable instructions, and the processor is configured to execute the computer executable instructions to implement the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method proposed in the above embodiment.

[0090] The embodiment further provides a storage medium having a computer program stored thereon, and the program is executed by a processor to implement the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method proposed in the above embodiment.

[0091] The storage medium proposed in the embodiment and the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method proposed in the above embodiment belong to the same inventive concept, and the technical details not described in the embodiment can be referred to the above embodiment, and the embodiment has the same beneficial effects as the above embodiment.

[0092] Through the above description of the embodiments, those skilled in the art can clearly understand that the present application can be realized by means of software and necessary general hardware, and of course can also be realized by hardware, but in many cases the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, and the computer software product can be stored in a computer readable storage medium, such as a floppy disk, a read-only memory (ROM), a random access memory (RAM), a FLASH, a hard disk or an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods of various embodiments of the present application.

[0093] Embodiment 2

[0094] Referring to FIGS. 1-2, one embodiment of the present application is different from the first embodiment in that the embodiment verifies the beneficial effects of the present application through comparative tests.

[0095] The experimental equipment in the embodiment includes a partial discharge collection sensor, a charging device, a damped oscillation voltage wave generator, a signal analyzer, an oscilloscope, etc. The experimental cable is a high-voltage cable with a length of 100 meters and a voltage of 22 kV. The experimental environment is indoor, with a temperature of 25℃ and a humidity of 50%.

[0096] The test steps are as follows:

[0097] Cable phase velocity test: the phase velocity test is performed in the same way as in Embodiment 1, and a phase velocity database is established.

[0098] Device installation: partial discharge collection sensors are installed at both ends of the cable.

[0099] Time synchronization: the two sensors are connected to the Internet using the PTP protocol, and time synchronization is performed.

[0100] Double-end monitoring: the partial discharge signals at both ends of the high-voltage cable are monitored using the sensors, and data is collected.

[0101] Partial discharge positioning: the partial discharge source is positioned using the method of the present application and the traditional method, respectively.

[0102] Data processing and analysis: the experimental data is processed, and the positioning accuracy and efficiency indicators are calculated.

[0103] Through comparative experiments of the method of the present application and the traditional method in the embodiment, the following conclusions can be drawn:

[0104] Positioning accuracy: the positioning accuracy of the method reaches 95%, which is significantly higher than 80% of the traditional method, indicating that the application has a significant advantage in accurately judging the position of the partial discharge source.

[0105] Monitoring efficiency: the monitoring time of the application is 10 seconds, which is double the monitoring efficiency compared to the traditional method of 20 seconds. This shows that the application can complete the partial discharge source positioning work in a shorter time, which is conducive to rapid response and timely maintenance measures, and improves the operation reliability of the power system.

[0106] It should be noted that the above examples are only used to illustrate the technical solutions of the application and are not limiting. Although the application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the application can be modified or replaced by equivalents without departing from the spirit and scope of the application. The technical solutions should be covered in the scope of the claims of the application.

Claims

1. A method for locating a partial discharge source in a high voltage cable high frequency partial discharge two-terminal monitoring partial discharge source location method, characterized by, The method comprises the following steps: acquiring operation data and phase velocity test data of the high-voltage cable; judging whether the high-voltage cable has a partial discharge fault based on the operation data, and if the high-voltage cable has a partial discharge fault, collecting partial discharge signals on both sides of the high-voltage cable through sensors on both sides of the high-voltage cable; performing Fourier transform on the partial discharge signals on both sides to obtain amplitude-frequency characteristics of the partial discharge signals, and pre-processing the collected partial discharge signals according to the amplitude-frequency characteristics to optimize and improve a phase difference algorithm; combining the phase velocity test data of the high-voltage cable, and locating a partial discharge source of the fault cable by using the improved phase difference algorithm.

2. The high voltage cable high frequency partial discharge double-ended monitoring partial discharge source location method of claim 1, wherein, The phase velocity test data comprises phase velocity data of the high-voltage cable when the high-voltage cable is stopped running; The test data is acquired by using a time domain method and a frequency domain method based on parameters of the high-voltage cable, and a phase velocity value is calculated based on a test result to establish a phase velocity database; The calculation of the phase velocity value is represented as: where f is the frequency, μ0is the vacuum permeability, μ r is the relative permeability of the high voltage cable, ε0is the vacuum permittivity, ε r is the relative permittivity of the high voltage cable, σ is the conductivity of the high voltage cable, ω is the angular frequency and ω = 2πf.

3. The method of claim 2, wherein the high voltage cable high frequency partial discharge two-terminal monitoring partial discharge source location method is characterized by, The judgment of whether the high-voltage cable has a partial discharge fault based on the operation data comprises the following steps: integrating operation data of different modes into unified features, performing feature fusion on the operation data of the high-voltage cable, and constructing a high-voltage cable state perception network; detecting and extracting features of partial discharge activity characteristics through the high-voltage cable state perception network, and when monitored partial discharge parameters exceed a preset fault threshold, the high-voltage cable has a partial discharge fault, otherwise, the high-voltage cable is in normal operation.

4. The method of claim 3, wherein the high voltage cable high frequency partial discharge two-terminal monitoring partial discharge source location method is characterized by, When there is a partial discharge fault, the partial discharge signals on both sides of the high-voltage cable are collected through sensors on both sides of the high-voltage cable, which comprises the following steps:

5. The partial discharge source location method of high voltage cable high frequency partial discharge two-terminal monitoring of claim 4, characterized in that, The sensors on both sides of the high-voltage cable monitor partial discharge signals at both ends of the high-voltage cable in real time; the sensors on both sides also use a PTP protocol for time synchronization, and upload the monitored partial discharge signals to an upper network. The PTP protocol time synchronization method comprises the following steps: defining an arbitrary sensor on one side of the high-voltage cable as a first sensor, and the other side as a second sensor; the first sensor sends partial discharge signals collected synchronously by each monitoring node at a local t1 moment, and saves the t1 moment in a time synchronization request packet to send to the second sensor; when the second sensor receives the partial discharge signals collected synchronously by each monitoring node, a local receiving moment t2 is recorded; when the second sensor receives the time synchronization request packet, the t1 moment in the time synchronization request packet is saved; the second sensor sends a delay request to the first sensor, and records a local sending moment t3; when the first sensor responds to the delay request of the second sensor, a receiving moment t4 is recorded, and the t4 moment is sent to the second sensor through a feedback communication link; 6. The method of partial discharge source location for high voltage cable high frequency partial discharge two-terminal monitoring of claim 4 or 5, wherein, the second sensor receives the data and saves the t4 moment, and after receiving the t4 moment, the high-voltage cable side with the second sensor collects the timestamp information t1, t2, t3, t4 locally; the time offset between the second sensor and the first sensor is calculated, and the time synchronization of the partial discharge signals on both sides of the high-voltage cable is completed. The time synchronized partial discharge signals are mathematically simulated in a double exponential decay and double exponential decay oscillation pulse form. In the partial discharge signal waveform, Gaussian white noise with a signal-to-noise ratio of 20 dB is superimposed, the waveform is analyzed, the direct wave and the reflected wave are separated, the Fourier transform is used to obtain the amplitude-frequency characteristic curve of the direct wave and the reflected wave, the amplitude-frequency characteristic curve is simulated by Monte Carlo, and the improved phase difference algorithm is obtained.

7. The method of partial discharge source location for high voltage cable high frequency partial discharge two-terminal monitoring of claim 2 or 6, wherein, In combination with the phase velocity test data of the high-voltage cable, the improved phase difference algorithm is used for partial discharge source positioning of the fault cable, including: replacing different types of cables to collect partial discharge signals; and obtaining the position of the partial discharge source by comparing the phase difference between the phase velocity test data of the high-voltage cable and the actual partial discharge signals collected.

8. A high voltage cable high frequency partial discharge two-terminal monitoring partial discharge source location system, characterized by, Comprise: A data acquisition module is configured to acquire operation data and phase velocity test data of a high-voltage cable. A judgment module is configured to judge whether the high-voltage cable has a partial discharge fault based on the operation data, and if the high-voltage cable has a partial discharge fault, collect partial discharge signals on both sides of the high-voltage cable through sensors on both sides of the high-voltage cable. An optimization module is configured to perform Fourier transform on the partial discharge signals on both sides to obtain amplitude-frequency characteristics of the partial discharge signals, and optimize an improved phase difference algorithm based on the amplitude-frequency characteristics and the collected partial discharge signals. A positioning module is configured to combine the phase velocity test data of the high-voltage cable and use the improved phase difference algorithm to position a partial discharge source of a fault cable. 9.An electronic device comprising: a memory and a processor; The memory is configured to store computer executable instructions, and the processor is configured to execute the computer executable instructions, and the computer executable instructions, when executed by the processor, implement the steps of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method of any one of claims 1 to 7. 10.A computer readable storage medium storing computer executable instructions, wherein the computer executable instructions, when executed by a processor, implement the steps of the high-voltage cable high-frequency partial discharge double-end monitoring partial discharge source positioning method of any one of claims 1 to 7.

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