Multi-point injection type cable partial discharge checking method, device and system

Abstract

The application provides a multi-point injection type cable partial discharge verification method, device and system, and belongs to the technical field of power safety, which comprises the following steps: determining an injection signal type, an injection signal parameter and a target injection point according to a verification purpose, and injecting the injection signal into the cable according to the target injection point, wherein the injection signal type comprises a partial discharge signal, an interference signal and a reflection simulation signal; then obtaining a positioning result of the partial discharge signal after positioning by a positioning device; determining a distance detection value between the injection point of the partial discharge signal and the positioning device according to the positioning result; and finally determining a verification result of the positioning accuracy of the positioning device according to a comparison result of the distance detection value and an actual distance value. The application can accurately detect the recognition and positioning capability of the positioning device on the partial discharge signal.

Description

Technical Field

[0001] This invention belongs to the field of power safety technology, and in particular relates to a multi-point injection method, device and system for detecting partial discharge in cables. Background Technology

[0002] Electricity, as a fundamental energy source vital to the national economy and people's livelihood, is the foundation of economic development and social progress. By the end of 2020, my country's installed power generation capacity reached 2 billion kilowatts, with an annual per capita electricity consumption of 5,000 kilowatt-hours. According to national energy planning forecasts, by 2050, my country's total electricity consumption will double compared to 2018 (6.84 trillion kilowatt-hours in 2018, 13.6 trillion kilowatt-hours in 2050), with an annual per capita electricity consumption reaching 9,700 kilowatt-hours. With the acceleration of urbanization and the development of renewable energy, the demand for power cables is increasing daily. Cable construction is an inevitable path for urban power transmission network construction and is hailed as the "blood vessels" of the national economy. Among them, the rapid construction of the massively used 10kV and 35kV distribution network AC cable transmission systems is an inevitable requirement of urbanization in the new era and a key foundation for ensuring the national economy and people's livelihood.

[0003] Cables play a crucial role in power transmission within modern urban power grid systems, and their operational status directly impacts the safety and stability of large-scale electrical systems. While the design life of cables is generally 20 to 30 years, cables in actual operation often experience permanent failures due to latent defects such as localized insulation deterioration or damage. Once a cable fault occurs, it can lead to the shutdown or even loss of control of large electrical systems, causing severe economic losses and social impact. Power cables in urban power supply systems are laid in cable trenches or directly buried underground. Under the influence of temperature, electrical stress, mechanical force, moisture, oil, organic compounds, alkalis, acids, and microorganisms, their insulation is susceptible to corrosion and penetration, leading to localized insulation defects. Simultaneously, underground power cables are frequently subjected to mechanical external forces that cause insulation damage, ultimately resulting in permanent cable failures. Surveys indicate that accidents caused by localized insulation defects in power cables account for approximately 40% of cable equipment accidents. Therefore, improving the manufacturing and testing capabilities of equipment for detecting localized insulation defects in power cables is crucial for ensuring the stable operation of power systems.

[0004] Currently, numerous studies by scholars both domestically and internationally utilize oscillating wave voltage methods to detect partial discharge in cross-linked polyethylene (XLPE) cables. This involves applying oscillating wave voltage to the cable to test for partial discharge and thus assess the cable's condition. Compared to traditional withstand voltage tests, oscillating wave voltage testing offers advantages such as shorter application time, ease of operation, portability, and flexibility, making it suitable for transport and detection of various defects in XLPE power cables. In recent years, various manufacturers have gradually introduced cable oscillating wave partial discharge detection devices to the market, and relevant testing system standards have been established. In 2018, the People's Republic of China's power industry standard, "Testing Standard for 6kV-35kV Cable Oscillating Wave Partial Discharge Measurement System," was promulgated. Following this, numerous research institutions and the power industry have conducted corresponding tests based on this standard. However, due to the requirement for highly precise measuring instruments and systems, as well as extensive operational experience, the calibration of oscillating wave detection systems is still in the exploratory stage, and standardized calibration devices have not yet been established. Furthermore, cable oscillating wave partial discharge detection devices have numerous parameters, and the standard only specifies the minimum requirements for some parameters. It does not address how to comprehensively evaluate and assess the quality of the device based on all these parameters. This means that there is no accurate basis for judgment when using oscillating wave partial discharge testing instruments in the field, which means that the detection of oscillating wave partial discharge in cables in various regions needs to be further improved.

[0005] According to relevant standards, the accuracy of partial discharge location verification for oscillating wave devices needs to be verified. The verification method involves applying a fixed-intensity partial discharge signal at a point on a cable of known length, then measuring the partial discharge signal at one end of the cable and locating the partial discharge based on the wave velocity. However, this method of partial discharge accuracy verification has significant limitations. It can only perform location measurements on a fixed length of cable, and the partial discharge signal injection method used only simulates a single partial discharge waveform, failing to accurately reproduce interference signals that may exist in various environments.

[0006] Therefore, existing technologies do not consider the impact of interference signals and actual long distances on positioning accuracy, and the performance evaluation of oscillating wave partial discharge positioning devices is inaccurate. Summary of the Invention

[0007] In view of this, embodiments of the present invention provide a multi-point injection cable partial discharge verification method, apparatus and system to solve the problem of inaccurate performance testing of existing oscillating wave partial discharge locating devices and other similar equipment.

[0008] In a first aspect, embodiments of the present invention provide a multi-point injection method for detecting partial discharge in cables, comprising:

[0009] The type of injection signal, injection signal parameters, and target injection point are determined according to the purpose of the verification, and the injection signal is injected into the cable according to the target injection point; wherein, the type of injection signal includes partial discharge signal, interference signal, and reflected analog signal;

[0010] The positioning result of the positioning device after locating the partial discharge signal is obtained, and the distance detection value between the injection point of the partial discharge signal and the positioning device is determined based on the positioning result.

[0011] The positioning accuracy verification result of the positioning device is determined based on the comparison between the detected distance value and the actual distance value.

[0012] In one possible implementation, determining the injected signal type, injected signal parameters, and target injection point according to the verification purpose includes:

[0013] When the purpose of the verification is to verify the ability to overcome environmental interference, the corresponding injection signal type is determined to be partial discharge signal and interference signal, the setting parameters of the first partial discharge signal and the interference signal are obtained, and two or more target injection points are set.

[0014] The target injection point includes a partial discharge signal injection point and one or more interference signal injection points.

[0015] In one possible implementation, the setting parameters for acquiring the first partial discharge signal and the interference signal include:

[0016] Obtain the rising edge and amplitude settings of the first partial discharge signal;

[0017] Obtain one or more of the following: type of interference signal, rising edge setting value, falling edge setting value, frequency setting value, and amplitude setting value;

[0018] The interference signal type includes one or more of the following: unipolar pulse, single-pulse noise signal, multi-pulse oscillation signal, and continuous high-frequency sine wave signal.

[0019] In one possible implementation, the first partial discharge signal and the interference signal are injected into the cable simultaneously.

[0020] In one possible implementation, determining the injected signal type, injected signal parameters, and target injection point according to the verification purpose includes:

[0021] When the purpose of the verification is long-distance simulation verification, the corresponding injection signal type is determined to be partial discharge signal and reflection simulation signal, the setting parameters of the second partial discharge signal and the reflection simulation signal are obtained, and two target injection points are set;

[0022] The target injection point includes a partial discharge signal injection point and a reflection simulation signal injection point.

[0023] In one possible implementation, the setting parameters for acquiring the second partial discharge signal and the reflected simulated signal include:

[0024] Obtain the second partial discharge signal and the reflected analog signal with the same waveform;

[0025] Wherein, the ratio of the amplitude of the reflected simulated signal to the amplitude of the second partial discharge signal is less than 1 and meets a preset range.

[0026] In one possible implementation, the second partial discharge signal is injected, and the reflected simulated signal is injected after a set time interval;

[0027] The set time interval is determined based on the target simulation distance corresponding to the long-distance simulation.

[0028] In one possible implementation, the step of determining the positioning accuracy verification result of the positioning device based on the comparison between the detected distance value and the actual distance value includes:

[0029] The difference between the detected distance value and the actual distance value is used to obtain the positioning error value;

[0030] When the positioning error value meets the preset positioning error range, the verification result is determined to be accurate.

[0031] Secondly, embodiments of the present invention provide a multi-point injection type cable partial discharge testing device, comprising:

[0032] The signal injection module is used to determine the type of injection signal, the parameters of the injection signal, and the target injection point according to the verification purpose, and to inject the injection signal into the cable according to the target injection point; wherein, the type of injection signal includes partial discharge signal, interference signal, and reflected analog signal;

[0033] The signal positioning module is used to acquire the positioning result after the positioning device locates the partial discharge signal, and to determine the distance detection value between the injection point of the partial discharge signal and the positioning device based on the positioning result.

[0034] The verification result determination module is used to determine the verification result of the positioning accuracy of the positioning device based on the comparison result between the distance detection value and the actual distance value.

[0035] Thirdly, embodiments of the present invention provide a multi-point injection cable partial discharge verification system, comprising: a multi-point injection cable partial discharge verification device, a signal generator, a flexible injection coupling device, and a positioning device as described in the second aspect above;

[0036] The signal generator is used to generate an injection signal according to the injection signal type and the injection signal parameters.

[0037] The flexible injection coupling device is used to inject the injection signal into the cable according to the target injection point;

[0038] The positioning device is used to perform positioning processing on the partial discharge signal to obtain a positioning result.

[0039] Fourthly, embodiments of the present invention provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the target detection method described above.

[0040] Fifthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the target detection method described above.

[0041] The beneficial effects of the multi-point injection cable partial discharge detection method provided in this invention are as follows:

[0042] This invention determines the type of injected signal, the parameters of the injected signal, and the target injection point based on the verification purpose. The injected signal is then injected into the cable according to the target injection point. The injected signal types include partial discharge signals, interference signals, and simulated reflection signals. The positioning result of the positioning device after locating the partial discharge signal is obtained. Based on the positioning result, the distance detection value between the injection point of the partial discharge signal and the positioning device is determined. Finally, the verification result of the positioning accuracy of the positioning device is determined by comparing the detected distance value with the actual distance value. This invention not only considers the impact of interference signals on the positioning accuracy of the positioning device during signal injection but also utilizes simulated reflection signals to simulate the reflection of long-distance partial discharge signals, using the signal time difference to achieve signal positioning. This enables accurate detection of the positioning device's ability to identify and locate partial discharge signals. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart illustrating the implementation of a multi-point injection method for partial discharge verification of cables provided in an embodiment of the present invention.

[0045] Figure 2 This is a structural diagram of a multi-point injection type cable partial discharge testing device provided in an embodiment of the present invention;

[0046] Figure 3 This is a measurement waveform diagram of a multi-point injection cable partial discharge verification method provided in an embodiment of the present invention;

[0047] Figure 4 This is an equivalent circuit diagram of the coupling device for a multi-point injection type cable partial discharge verification method provided in an embodiment of the present invention;

[0048] Figure 5 This is a coupling device structure and installation diagram of a multi-point injection type cable partial discharge verification method provided in an embodiment of the present invention;

[0049] Figure 6 This is a schematic diagram illustrating the synchronous injection effect of interference signals in a multi-point injection cable partial discharge verification method provided in an embodiment of the present invention.

[0050] Figure 7 This is a long-distance simulation schematic diagram of a multi-point injection cable partial discharge verification method provided in an embodiment of the present invention;

[0051] Figure 8 This is a circuit diagram for selecting the matching circuit of a multi-point injection cable partial discharge verification method provided in an embodiment of the present invention;

[0052] Figure 9 This is a schematic diagram of a multi-point injection type cable partial discharge testing device provided in an embodiment of the present invention;

[0053] Figure 10 This is a schematic diagram of a multi-point injection type cable partial discharge detection system provided in an embodiment of the present invention;

[0054] Figure 11 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0055] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0056] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0057] See Figure 1 The diagram illustrates a flowchart of a multi-point injection method for partial discharge testing of cables provided by an embodiment of the present invention. The method includes the following steps:

[0058] S101. Determine the type of injection signal, injection signal parameters, and target injection point according to the purpose of the verification, and inject the injection signal into the cable according to the target injection point.

[0059] In this embodiment of the invention, the verification purpose includes verification of the ability to overcome environmental interference and long-distance simulation verification. The injected signal types include partial discharge signals, interference signals and reflected simulation signals. The location of the target injection point is randomly selected on the cable.

[0060] In one possible implementation, determining the injected signal type, injected signal parameters, and target injection point based on the verification purpose includes:

[0061] When the purpose of the verification is to verify the ability to overcome environmental interference, the corresponding injection signal types are determined to be partial discharge signal and interference signal, the setting parameters of the first partial discharge signal and interference signal are obtained, and two or more target injection points are set.

[0062] The target injection point includes a partial discharge signal injection point and one or more interference signal injection points.

[0063] In this embodiment of the invention, to ensure that the positioning device can effectively locate partial discharge signals, it is necessary to first overcome noise interference in the measurement environment and ensure that the partial discharge waveforms used as the injected signal and reflected signal during the partial discharge positioning process are the same signal, i.e., the transmission result of the first partial discharge signal. This embodiment of the invention is based on a multi-point signal injection structure, simultaneously injecting first partial discharge signals of different forms and interference signals into the cable. The device is then examined to see if it can identify the first partial discharge signal amidst numerous interferences, and this result is used as the basis for evaluating the noise suppression capability of the partial discharge positioning device.

[0064] In one possible implementation, the setting parameters for obtaining the first partial discharge signal and the interference signal include:

[0065] Obtain the rising edge and amplitude setting value of the first partial discharge signal;

[0066] Acquire one or more of the following: type of interference signal, rising edge setting value, falling edge setting value, frequency setting value, and amplitude setting value;

[0067] The types of interference signals include one or more of the following: unipolar pulse, single-pulse noise signal, multi-pulse oscillation signal, and continuous high-frequency sine wave signal.

[0068] In this embodiment of the invention, the rising edge of the first partial discharge signal is set, and the rising edge of the first partial discharge signal is adjusted from 1µs to 10ns to examine the response characteristics of the measured positioning device to different rising edge signals; at the same time, the amplitude of the first partial discharge signal, i.e., the discharge amount, is set, with a setting range of 1pC-20nC, so as to realize multiple combinations of different rising edges and discharge amounts of the first partial discharge signal. During the measurement process, the first partial discharge signal is repeatedly injected at a repetition frequency of 100-200Hz at fixed time intervals.

[0069] For interference signals, a single-pulse noise signal was set with both rising and falling edges greater than 10µs, and an amplitude of 10%-100% of the first partial discharge signal amplitude, to simulate possible operational overvoltage interference signals in the cable system. The signal-to-noise ratio of the equipment was also measured. A multi-pulse oscillation signal was set with both rising and falling edges greater than 10µs, and an amplitude of 10%-100% of the first partial discharge signal amplitude, to simulate possible operational overvoltage interference oscillation signals in the cable system. A continuous high-frequency sine wave was set with a frequency less than 1MHz or greater than 100MHz, and an amplitude of 10%-100% of the first partial discharge signal amplitude, to simulate possible switching equipment noise signals and high-frequency radio frequency interference signals in the cable system. Furthermore, since the noise interference signal is continuous, this embodiment uses a continuous injection method into the cable.

[0070] See Figure 2 This diagram illustrates the structure of a multi-point injection type cable partial discharge verification device according to an embodiment of the present invention. Several randomly selected injection points are located on the cable. A measurement positioning device equipped with a capacitance sensor is connected to one end of the cable. The high-voltage output end of the partial discharge signal is connected to the cable conductor core, and the other end is grounded together with the outer sheath of the sample cable. When verifying the accuracy of the positioning device, a signal generator emits a pulse signal of fixed amplitude, and the capacitance sensor measures the signal propagating through the cable conductor core.

[0071] During the injection and positioning of partial discharge signals, the total cable length can be measured using a cable length measuring instrument before activating the positioning device. The measured cable length L is then input into the positioning device. The positioning device detects the injected partial discharge signal and its reflected signal after far-end reflection. See [link to documentation]. Figure 3 The diagram illustrates the measurement waveform of a multi-point injection cable partial discharge verification method provided by an embodiment of the present invention. The positioning device locates the partial discharge signal based on the time difference between the injected and reflected signals, the total cable length L, and the signal transmission speed in the cable, obtaining the distance l between the injection point of the partial discharge signal and the positioning device. The formula for calculating l is as follows:

[0072]

[0073] Where L is the total length of the cable; ν = 2 × 10 8 m / s is the signal transmission wave speed in the cable; t is the time difference between the injected signal and the reflected signal.

[0074] To effectively inject a partial discharge signal, a capacitor couples the injected signal into the cable conductor core. (See [link]). Figure 4 This diagram illustrates the equivalent circuit diagram of the coupling device in a multi-point injection cable partial discharge verification method according to an embodiment of the present invention. The coupling device and the cable body can be equivalently represented by several capacitors connected in series. Capacitor C1 is the capacitance of the coupling device itself, C2 is the equivalent capacitance between the cable core at the cable location covered by the coupling device and the electrodes of the coupling device, and C3 is the equivalent capacitance of the cable conductor to ground. Figure 4 It can be seen that by adjusting the capacitance value C1, the voltage value U of the cable conductor core can be significantly increased. cable See also Figure 5 The diagram shows the coupling device structure and installation diagram of a multi-point injection cable partial discharge verification method provided by an embodiment of the present invention. The coupling medium is made of the same cross-linked polyethylene material as the main insulation of the cable. The capacitor plate is designed as a 200um thick copper foil structure. This structure can effectively ensure good overall flexibility. In the process of use, it can be used with insulating tape to complete the full coverage of the cable.

[0075] In one possible implementation, the first partial discharge signal and the interference signal are injected into the cable simultaneously.

[0076] In this embodiment of the invention, a first partial discharge signal and multiple interference signals are simultaneously injected into the cable, causing multiple sets of signals to be transmitted synchronously and superimposed on each other in the cable. See also Figure 6This illustration shows a schematic diagram of the synchronous injection effect of interference signals in a multi-point injection-type cable partial discharge verification method provided by an embodiment of the present invention. Assuming the signal at injection point 1 is the first partial discharge signal, after the injection signal is measured at the measuring end of the positioning device, the injection signals from injection points 2-4 will be received simultaneously, along with the transmitted signals after far-end reflections. The positioning device can identify and locate the first partial discharge signal among multiple signals. This embodiment of the present invention uses a synchronous injection method of partial discharge signals and interference signals, which can verify the positioning device's ability to identify and locate partial discharge signals under noise interference.

[0077] In one possible implementation, determining the injected signal type, injected signal parameters, and target injection point based on the verification purpose includes:

[0078] When the purpose of the verification is long-distance simulation verification, the corresponding injection signals are determined to be partial discharge signals and reflection simulation signals. The setting parameters of the second partial discharge signal and reflection simulation signal are obtained, and two target injection points are set.

[0079] The target injection point includes a partial discharge signal injection point and a reflection simulation signal injection point.

[0080] During the operation of the partial discharge locator, partial discharge points are located for long power cables. In some scenarios, the distance between the locating points may be greater than 1,000m or even several kilometers. However, it is difficult to build a measurement circuit that is several kilometers long when measuring the long-distance locating function of the partial discharge locator under laboratory conditions.

[0081] See Figure 7 This diagram illustrates a long-distance simulation principle of a multi-point injection cable partial discharge verification method provided by an embodiment of the present invention. In this embodiment, for the purpose of long-distance simulation verification, two target injection points are selected on a short-distance cable, with the distance between the two injection points within 1 meter. Injection point 1 serves as the injection point for the second partial discharge signal, and injection point 2 serves as the injection point for the reflected simulation signal. The reflected simulation signal is used to simulate the reflection signal of the second partial discharge signal after passing through the far end of the cable, and to locate the second partial discharge signal, verifying the positioning accuracy of the measured positioning device under long-distance simulation.

[0082] In one possible implementation, the setting parameters for obtaining the second partial discharge signal and the reflected simulated signal include:

[0083] Obtain a second partial discharge signal and a reflected analog signal with the same waveform;

[0084] The ratio of the amplitude of the reflected simulated signal to the amplitude of the second partial discharge signal is less than 1 and meets the preset range.

[0085] In this embodiment of the invention, the reflected simulated signal is the reflected signal of the second partial discharge signal. It needs to meet the correlation between the incident signal and the reflected signal in the actual test. Therefore, the waveforms of the second partial discharge signal and the reflected simulated signal are the same or similar. The two signal waveforms have the same rising edge and falling edge, and only differ in amplitude. The amplitude of the reflected simulated signal is greater than 20% and less than 50% of the amplitude of the second partial discharge signal, so as to simulate the amplitude attenuation of high-frequency signal transmission in real cables.

[0086] Furthermore, in long-distance simulation verification, the injected reflected simulated signal is treated as a reflected signal, and there are no other reflected signals in the cable; otherwise, it would affect the positioning device's measurement and analysis of the effective partial discharge signal. Based on this, see [link to relevant documentation]. Figure 8 This diagram illustrates the matching circuit selection for a multi-point injection-type cable partial discharge verification method according to an embodiment of the present invention. An adjustable matching resistor R is added at the end of the cable furthest from the positioning device to eliminate reflections of the injected signal within the cable. Given that the transmission impedance of a 10kV single-core high-voltage cable is approximately 30Ω, an adjustable resistor with a resistance of 30Ω is selected as the matching resistor. Before conducting long-distance simulation verification, a pulse signal is injected using a signal generator, and an oscilloscope is used to simultaneously observe the presence of a reflected signal at the injection end. The adjustable matching resistor R is adjusted until the reflected signal disappears, and this resistance value is used as the matching resistor value.

[0087] In one possible implementation, a second partial discharge signal is injected, and a reflected analog signal is injected after a set time interval.

[0088] The set time interval is determined based on the target simulation distance corresponding to the long-distance simulation.

[0089] In this embodiment of the invention, the signal delay from signal injection point 1 to signal injection point 2 is controlled by adding a coaxial transmission line between the two signal injection points. The signal generation device used at each injection point is the same signal generator, and its operating delay is identical at each injection point. To avoid delay errors caused by temperature variations and other factors in crystal oscillator-based delays, this scheme selects coaxial transmission lines of different lengths for signal delay control. When the trigger level signal is transmitted in the coaxial line, its wave velocity is approximately 2 × 10⁻⁶. 8The wave velocity is m / s. Because the coaxial cable uses the same insulation and conductor materials as the cable under test, its wave velocity is the same as the signal transmission wave velocity in the cable. When a coaxial cable of length 'a' is used for trigger signal transmission, where 'a' is the signal transmission distance within the set time delay during long-distance simulation, the time difference between the second partial discharge signal and the reflected simulated signal is calculated based on 'a'. The positioning device then obtains the positioning result of the second partial discharge signal. Furthermore, the coaxial transmission line is small in size, easy to use and replace, and different lengths of coaxial transmission lines can be used according to the needs of long-distance simulation to control the signal delay of the injected and reflected signals.

[0090] The two signal injection points work as follows: After connecting the two signal injection points and the trigger signal transmission coaxial line, a trigger square wave signal is injected at signal injection point 1. Signal injection point 1 starts working first and injects a high-amplitude voltage waveform signal 1 into the cable. At the same time, the trigger signal is transmitted in the coaxial line. After the propagation length a, injection point 2 starts working and injects a low-amplitude reflected analog signal into the cable.

[0091] S102. Obtain the positioning result after the positioning device locates the partial discharge signal, and determine the distance detection value between the injection point of the partial discharge signal and the positioning device based on the positioning result.

[0092] In this embodiment of the invention, the positioning device measures the time difference between the partial discharge injection signal and the reflected signal, and calculates the distance between the partial discharge signal injection point and the positioning device according to the distance calculation formula based on the time difference, thereby realizing the positioning of the partial discharge signal.

[0093] S103. Determine the verification result of the positioning accuracy of the positioning device based on the comparison result between the distance detection value and the actual distance value.

[0094] In one possible implementation, the verification result of the positioning accuracy of the positioning device, based on the comparison between the detected distance value and the actual distance value, includes:

[0095] The difference between the detected distance value and the actual distance value is used to obtain the positioning error value;

[0096] When the positioning error value meets the preset positioning error range, the verification result is judged to be accurate.

[0097] In this embodiment of the invention, different positioning error ranges can be set according to actual needs, thereby achieving the purpose of verifying the positioning device.

[0098] In this embodiment, the type of injected signal, the parameters of the injected signal, and the target injection point are determined according to the verification purpose. The injected signal is then injected into the cable according to the target injection point. The injected signal types include partial discharge signals, interference signals, and simulated reflection signals. The positioning result after the positioning device locates the partial discharge signal is then obtained. Based on the positioning result, the distance detection value between the injection point of the partial discharge signal and the positioning device is determined. Finally, the verification result of the positioning accuracy of the positioning device is determined based on the comparison between the distance detection value and the actual distance value. This invention not only considers the impact of interference signals on the positioning accuracy of the positioning device when injecting signals, but also uses simulated reflection signals to simulate the reflection of long-distance partial discharge signals, and uses the signal time difference to achieve signal positioning, thus accurately detecting the positioning device's ability to identify and locate partial discharge signals.

[0099] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not limit the implementation process of the embodiments of the present invention.

[0100] The following are embodiments of the apparatus of the present invention. For details not described herein, please refer to the above-described method embodiments.

[0101] Figure 9 This diagram illustrates the structure of a target detection device according to an embodiment of the present invention. For ease of explanation, only the parts relevant to the embodiment of the present invention are shown, such as... Figure 9 The target detection device shown includes: a signal injection module 901, a signal positioning module 902, and a verification result determination module 903.

[0102] The signal injection module 901 is used to determine the type of injection signal, the parameters of the injection signal, and the target injection point according to the purpose of the verification, and to inject the injection signal into the cable according to the target injection point; wherein, the injection signal type includes partial discharge signal, interference signal and reflection simulation signal.

[0103] The signal positioning module 902 is used to obtain the positioning result after the positioning device locates the partial discharge signal, and to determine the distance detection value between the injection point of the partial discharge signal and the positioning device based on the positioning result.

[0104] The verification result determination module 903 is used to determine the verification result of the positioning accuracy of the positioning device based on the comparison result between the distance detection value and the actual distance value.

[0105] In one possible implementation, the signal injection module 901 is specifically used to: when the verification purpose is to verify the ability to overcome environmental interference, determine that the corresponding injection signal type is a partial discharge signal and an interference signal, obtain the setting parameters of the first partial discharge signal and the interference signal, and set two or more target injection points.

[0106] The target injection point includes a partial discharge signal injection point and one or more interference signal injection points.

[0107] In one possible implementation, the signal injection module 901 is specifically used to: acquire the rising edge and amplitude setting value of the first partial discharge signal;

[0108] Acquire one or more of the following: type of interference signal, rising edge setting value, falling edge setting value, frequency setting value, and amplitude setting value;

[0109] The types of interference signals include one or more of the following: unipolar pulse, single-pulse noise signal, multi-pulse oscillation signal, and continuous high-frequency sine wave signal.

[0110] In one possible implementation, the signal injection module 901 is specifically used to inject the first partial discharge signal and the interference signal into the cable simultaneously.

[0111] In one possible implementation, the signal injection module 901 is specifically used to: when the verification purpose is long-distance simulation verification, determine that the corresponding injection signals are partial discharge signals and reflection simulation signals, obtain the setting parameters of the second partial discharge signal and reflection simulation signal, and set two target injection points;

[0112] The target injection point includes a partial discharge signal injection point and a reflection simulation signal injection point.

[0113] In one possible implementation, the signal injection module 901 is specifically used to: acquire a second partial discharge signal and a reflected analog signal with the same waveform;

[0114] The ratio of the amplitude of the reflected simulated signal to the amplitude of the second partial discharge signal is less than 1 and meets the preset range.

[0115] In one possible implementation, the signal injection module 901 is further configured to: inject a second partial discharge signal and inject a reflected analog signal after a set time interval;

[0116] The set time interval is determined based on the target simulation distance corresponding to the long-distance simulation.

[0117] In one possible implementation, the verification result determination module 903 is specifically used to: subtract the distance detection value from the actual distance value to obtain the positioning error value;

[0118] When the positioning error value meets the preset positioning error range, the verification result is judged to be accurate.

[0119] In this embodiment, the type of injected signal, the parameters of the injected signal, and the target injection point are determined according to the verification purpose. The injected signal is then injected into the cable according to the target injection point. The injected signal types include partial discharge signals, interference signals, and simulated reflection signals. The positioning result after the positioning device locates the partial discharge signal is then obtained. Based on the positioning result, the distance detection value between the injection point of the partial discharge signal and the positioning device is determined. Finally, the verification result of the positioning accuracy of the positioning device is determined based on the comparison between the distance detection value and the actual distance value. This invention not only considers the impact of interference signals on the positioning accuracy of the positioning device when injecting signals, but also uses simulated reflection signals to simulate the reflection of long-distance partial discharge signals, and uses the signal time difference to achieve signal positioning, thus accurately detecting the positioning device's ability to identify and locate partial discharge signals.

[0120] See Figure 10 The diagram illustrates a multi-point injection cable partial discharge verification system provided by an embodiment of the present invention. The system includes: a multi-point injection cable partial discharge verification device, a signal generator, a flexible injection coupling device, and a positioning device.

[0121] The signal generator is used to generate an injection signal based on the type and parameters of the injection signal.

[0122] A flexible injection coupling device is used to inject an injection signal into a cable according to the target injection point;

[0123] The positioning device is used to perform positioning processing on partial discharge signals to obtain positioning results.

[0124] The above are system embodiments of the present invention. For details not described herein, please refer to the above-described method embodiments.

[0125] See Figure 11 This illustrates a schematic diagram of an electronic device provided by an embodiment of the present invention. For example... Figure 11 As shown, the electronic device 11 of this embodiment includes: a processor 110, a memory 111, and a computer program 112 stored in the memory 111 and executable on the processor 110. When the processor 110 executes the computer program 112, it implements the steps in the various target detection method embodiments described above, for example... Figure 1 Steps S101 to S103 are shown. Alternatively, when the processor 110 executes the computer program 112, it implements the functions of each module / unit in the above-described device embodiments, for example... Figure 9The functions of modules 901 to 903 are shown.

[0126] For example, the computer program 112 can be divided into one or more modules / units, which are stored in the memory 111 and executed by the processor 110 to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program 112 in the electronic device 11. For example, the computer program 112 can be divided into... Figure 9 Modules 901 to 903 are shown.

[0127] The electronic device 11 can be a desktop computer, laptop, handheld computer, cloud server, or other computing device. The electronic device 11 may include, but is not limited to, a processor 110 and a memory 111. Those skilled in the art will understand that... Figure 11 This is merely an example of electronic device 11 and does not constitute a limitation on electronic device 11. It may include more or fewer components than shown, or combine certain components, or different components. For example, the electronic device may also include input / output devices, network access devices, buses, etc.

[0128] The processor 110 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0129] The memory 111 can be an internal storage unit of the electronic device 11, such as a hard disk or RAM of the electronic device 11. The memory 111 can also be an external storage device of the electronic device 11, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the electronic device 11. Furthermore, the memory 111 can include both internal and external storage units of the electronic device 11. The memory 111 is used to store the computer program and other programs and data required by the electronic device. The memory 111 can also be used to temporarily store data that has been output or will be output.

[0130] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0131] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0132] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0133] In the embodiments provided by this invention, it should be understood that the disclosed devices / electronic devices and methods can be implemented in other ways. For example, the device / electronic device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0134] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0135] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0136] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various target detection method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0137] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A multi-point injection method for partial discharge testing of cables, characterized in that, include: The type of injection signal, injection signal parameters, and target injection point are determined according to the purpose of the verification, and the injection signal is injected into the cable according to the target injection point; wherein, the type of injection signal includes partial discharge signal, interference signal, and reflected analog signal; The positioning result of the positioning device after locating the partial discharge signal is obtained, and the distance detection value between the injection point of the partial discharge signal and the positioning device is determined based on the positioning result. The positioning accuracy verification result of the positioning device is determined based on the comparison between the detected distance value and the actual distance value. The process of determining the type of injected signal, the parameters of the injected signal, and the target injection point according to the purpose of verification includes: When the purpose of the verification is long-distance simulation verification, the corresponding injection signal type is determined to be partial discharge signal and reflection simulation signal, the setting parameters of the second partial discharge signal and the reflection simulation signal are obtained, and two target injection points are set; The target injection point includes a partial discharge signal injection point and a reflection simulation signal injection point.

2. The multi-point injection method for partial discharge testing of cables according to claim 1, characterized in that, The process of determining the type of injected signal, the parameters of the injected signal, and the target injection point according to the purpose of verification includes: When the purpose of the verification is to verify the ability to overcome environmental interference, the corresponding injection signal type is determined to be partial discharge signal and interference signal, the setting parameters of the first partial discharge signal and the interference signal are obtained, and two or more target injection points are set. The target injection point includes a partial discharge signal injection point and one or more interference signal injection points.

3. The multi-point injection method for partial discharge testing of cables according to claim 2, characterized in that, The setting parameters for acquiring the first partial discharge signal and the interference signal include: Obtain the rising edge and amplitude settings of the first partial discharge signal; Obtain one or more of the following: type of interference signal, rising edge setting value, falling edge setting value, frequency setting value, and amplitude setting value; The interference signal type includes one or more of the following: unipolar pulse, single-pulse noise signal, multi-pulse oscillation signal, and continuous high-frequency sine wave signal.

4. The multi-point injection method for partial discharge testing of cables according to claim 2, characterized in that, The first partial discharge signal and the interference signal are injected into the cable simultaneously.

5. The multi-point injection method for partial discharge testing of cables according to claim 1, characterized in that, The setting parameters for acquiring the second partial discharge signal and the reflected simulated signal include: Obtain the second partial discharge signal and the reflected analog signal with the same waveform; Wherein, the ratio of the amplitude of the reflected simulated signal to the amplitude of the second partial discharge signal is less than 1 and meets a preset range.

6. The multi-point injection method for partial discharge testing of cables according to claim 1, characterized in that, The second partial discharge signal is injected, and the reflected simulated signal is injected after a set time interval; The set time interval is determined based on the target simulation distance corresponding to the long-distance simulation.

7. The multi-point injection method for partial discharge testing of cables according to claim 1, characterized in that, The verification result for determining the positioning accuracy of the positioning device based on the comparison between the detected distance value and the actual distance value includes: The difference between the detected distance value and the actual distance value is used to obtain the positioning error value; When the positioning error value meets the preset positioning error range, the verification result is determined to be accurate.

8. A multi-point injection type cable partial discharge detection device, characterized in that, include: The signal injection module is used to determine the type of injection signal, the parameters of the injection signal, and the target injection point according to the verification purpose, and to inject the injection signal into the cable according to the target injection point; wherein, the type of injection signal includes partial discharge signal, interference signal, and reflected analog signal; The signal positioning module is used to acquire the positioning result after the positioning device locates the partial discharge signal, and to determine the distance detection value between the injection point of the partial discharge signal and the positioning device based on the positioning result. The verification result determination module is used to determine the verification result of the positioning accuracy of the positioning device based on the comparison result between the distance detection value and the actual distance value. Specifically, the signal injection module is used for: When the purpose of the verification is long-distance simulation verification, the corresponding injection signal type is determined to be partial discharge signal and reflection simulation signal, the setting parameters of the second partial discharge signal and the reflection simulation signal are obtained, and two target injection points are set; The target injection point includes a partial discharge signal injection point and a reflection simulation signal injection point.

9. A multi-point injection type cable partial discharge detection system, characterized in that, include: The multi-point injection type cable partial discharge detection device, signal generator, flexible injection coupling device, and positioning device as described in claim 8; The signal generator is used to generate an injection signal according to the injection signal type and the injection signal parameters; The flexible injection coupling device is used to inject the injection signal into the cable according to the target injection point; The positioning device is used to perform positioning processing on the partial discharge signal to obtain a positioning result.

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