Partial discharge double-end positioning method and device, computer equipment, readable storage medium and program product

Abstract

The invention relates to a partial discharge double-end positioning method and device, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit; positioning a partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal; extracting feature information of the partial discharge signal from the first discharge pulse frame, and positioning the partial discharge signal from the second discharge pulse frame based on the feature information to obtain a second peak moment of the partial discharge signal; and determining the partial discharge position based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment and the second peak moment. By adopting the method, the detection sensitivity can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of partial discharge detection, and in particular to a partial discharge dual-terminal positioning method, apparatus, computer equipment, computer-readable storage medium, and computer program product. Background Art

[0002] Partial discharge (PD) is a non-penetrating discharge that occurs in a localized area of an insulating medium under the influence of an electric field. Although this discharge has low energy, its long-term presence can gradually erode the insulation material, ultimately leading to insulation failure and even equipment damage. Therefore, accurately detecting and locating PD is crucial to ensuring the safe operation of power cables.

[0003] In traditional technology, partial discharge positioning mainly adopts dual-end positioning technology. The dual-end positioning technology in traditional technology requires the use of acquisition devices deployed at both ends of the cable to capture the partial discharge signals respectively, so as to locate the partial discharge by comparing the time difference between the partial discharge signals captured at both ends.

[0004] However, the detection sensitivity of the traditional dual-end positioning technology is low, and both ends must collect strong partial discharge signals for positioning. If the partial discharge signal of the cable body is weak or the environmental interference is large, resulting in one end being unable to identify the partial discharge signal, partial discharge positioning cannot be achieved. Summary of the Invention

[0005] Based on this, it is necessary to provide a partial discharge double-terminal positioning method, device, computer equipment, computer-readable storage medium and computer program product that can improve detection sensitivity in order to address the above technical problems.

[0006] In a first aspect, the present application provides a partial discharge dual-terminal positioning method, comprising:

[0007] receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, and the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected;

[0008] Locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal;

[0009] extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal;

[0010] The partial discharge position is determined based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0011] In one embodiment, the method is applied to a partial discharge dual-terminal locating system, which includes a measurement host and a plurality of acquisition units, wherein the acquisition units include a first acquisition unit and at least one second acquisition unit adjacent to the first acquisition unit;

[0012] Before receiving the first discharge pulse frame sent by the first acquisition unit, the method further includes:

[0013] When a partial discharge signal with a signal amplitude exceeding a preset voltage threshold is detected by the first acquisition unit, a partial discharge location event is triggered, a partial discharge detection time corresponding to the partial discharge signal is determined based on a network-wide synchronized time accumulation counter, and the partial discharge detection time and the partial discharge location event are sent to each second acquisition unit;

[0014] Acquiring, by a first acquisition unit, a plurality of first discharge waveform values corresponding to the partial discharge detection moment from a memory of the local end, generating a first discharge pulse frame based on each first discharge waveform value, and uploading the first discharge pulse frame to a measurement host;

[0015] In response to a partial discharge location event, the second acquisition unit obtains multiple second discharge waveform values corresponding to the partial discharge detection moment from the local end memory, generates a second discharge pulse frame based on each second discharge waveform value, and uploads the second discharge pulse frame to the measurement host.

[0016] In one embodiment, obtaining a plurality of first discharge waveform values corresponding to the partial discharge detection moment from a memory of the local end includes:

[0017] querying a first write address corresponding to the partial discharge detection moment from a memory at a local end of the first acquisition unit;

[0018] determining a first write address segment based on the first write address and a preset first signal quantity;

[0019] Taking a plurality of first discharge waveform values in a first write address segment;

[0020] Acquiring multiple second discharge waveform values corresponding to the partial discharge detection moment from the memory of the local end, including:

[0021] querying a second write address corresponding to the partial discharge detection moment from a memory at a local end of the second acquisition unit;

[0022] determining a second write address segment based on the second write address and a preset second signal quantity;

[0023] A plurality of second discharge waveform values in the second write address segment are read.

[0024] In one embodiment, the partial discharge dual-terminal location system further includes a communication unit, and the communication unit and each acquisition unit are cascaded via a data transmission line;

[0025] Before determining the partial discharge detection time corresponding to the partial discharge signal based on the network-wide synchronized time accumulation counter, the method further includes:

[0026] Sending test data to the corresponding subsequent units through each preceding unit, wherein the preceding unit includes a communication unit and at least one of the acquisition units, and the subsequent unit includes at least one of the acquisition units;

[0027] Dynamically adjust the voltage-controlled crystal oscillator (VCO) of each subsequent unit based on the number of clock edges of the received test data, so that the clock frequency and phase of the adjacent subsequent units are consistent with those of the previous units.

[0028] Sending a delay measurement frame to the corresponding subsequent unit through each preceding unit, receiving feedback information returned by the corresponding subsequent unit in response to the delay measurement frame, and calculating the transmission delay between each preceding unit and the corresponding subsequent unit based on the feedback information;

[0029] Starting from the communication unit, the whole network synchronization time frame is issued to each acquisition unit step by step. Each whole network synchronization time frame includes the whole network synchronization timestamp of the previous unit and the transmission delay calculated by the previous unit. The whole network synchronization time frame is used to update the whole network synchronization timestamp of the receiving end. The error between the whole network synchronization timestamps updated by each acquisition unit is less than the preset error threshold.

[0030] In one embodiment, locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal includes:

[0031] Acquire a first starting timestamp of a first discharge pulse frame and a second starting timestamp of each second discharge pulse frame;

[0032] Detecting a start time difference between the first start timestamp and each second start timestamp;

[0033] When at least one start time difference is less than a corresponding preset time difference threshold, a partial discharge signal is located from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal, wherein the preset time difference threshold is determined based on a communication distance and a cable length corresponding to the start time difference.

[0034] In one embodiment, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information to obtain the second peak moment of the partial discharge signal includes:

[0035] performing feature recognition on the second discharge pulse frame based on the feature information;

[0036] When a target signal waveform having a similarity with the characteristic information higher than a preset similarity threshold is identified from the second discharge pulse frame, the peak moment of the target signal waveform is determined as the second peak moment of the partial discharge signal.

[0037] In a second aspect, the present application further provides a partial discharge double-end positioning device, comprising:

[0038] a receiving module, configured to receive a first discharge pulse frame sent by the first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, wherein the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected;

[0039] A first positioning module is used to locate the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal;

[0040] a second positioning module, configured to extract characteristic information of the partial discharge signal from the first discharge pulse frame, locate the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtain a second peak moment of the partial discharge signal;

[0041] The determination module is configured to determine a partial discharge position based on first cable positioning information corresponding to the first acquisition unit, second cable positioning information corresponding to the second acquisition unit, a first peak moment, and a second peak moment.

[0042] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0043] receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, and the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected;

[0044] Locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal;

[0045] extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal;

[0046] The partial discharge position is determined based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0047] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the following steps:

[0048] receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, and the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected;

[0049] Locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal;

[0050] extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal;

[0051] The partial discharge position is determined based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0052] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the following steps:

[0053] receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, and the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected;

[0054] Locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal;

[0055] extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal;

[0056] The partial discharge position is determined based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0057] The above-mentioned partial discharge dual-terminal locating method, apparatus, computer device, computer-readable storage medium and computer program product first receive a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal whose signal amplitude exceeds a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event. The partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected, thereby realizing a single-end triggering of the partial discharge dual-terminal locating method. That is, as long as any acquisition unit identifies the partial discharge signal, the acquisition unit that identifies the partial discharge signal can be triggered. The unit and its adjacent acquisition units upload discharge pulse frames; then, by locating the local discharge signal from the first discharge pulse frame, a first peak moment of the local discharge signal is obtained, characteristic information of the local discharge signal is extracted from the first discharge pulse frame, and based on the characteristic information, the local discharge signal is located from the second discharge pulse frame to obtain a second peak moment of the local discharge signal, thereby achieving the capture of the local discharge signal from the second discharge pulse frame with a weaker signal or stronger noise, thereby determining the moment when the local discharge signal is collected by both ends; and then, by determining the local discharge position based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment, dual-end positioning of the local discharge can be achieved.

[0058] In this way, if the PD signal from the cable itself is weak or the environmental interference is significant, preventing one end from identifying the PD signal, the end that can identify the PD signal can trigger the upload of a discharge pulse frame. Feature information is extracted from the first PD pulse frame with a stronger PD signal, and based on this feature information, the PD signal is identified in the second PD pulse frame with a weaker PD signal. This solution enables dual-end positioning of even weaker PD signals, significantly improving detection reliability in weak signal scenarios and overcoming the technical drawback of traditional methods, where positioning fails due to single-end signal loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0060] Figure 1 This is a structural diagram of a partial discharge dual-terminal positioning system in one embodiment of the present application;

[0061] Figure 2 This is a flow chart of a partial discharge double-terminal positioning method in one embodiment of the present application;

[0062] Figure 3 This is a flow chart of a partial discharge double-terminal positioning method in another embodiment of the present application;

[0063] Figure 4 This is a pulse waveform diagram of the master and slave ends in one embodiment of the present application;

[0064] Figure 5 This is a structural block diagram of a partial discharge double-terminal positioning device in one embodiment of the present application;

[0065] Figure 6 This is a diagram of the internal structure of a computer device in one embodiment of the present application. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0067] Partial discharge (PD) is a key indicator of insulation degradation in high-voltage power cables. It occurs when a non-penetrating discharge occurs in a localized area of the insulating medium under the influence of an electric field. Although the energy of a single discharge is relatively small, long-term PD can gradually erode the insulation material, ultimately leading to insulation degradation and even equipment breakdown. Therefore, accurately detecting and locating PD is crucial for assessing cable insulation condition and preventing power accidents.

[0068] Traditionally, partial discharge (PD) location has primarily relied on dual-terminal positioning technology. This technology requires data acquisition devices deployed at both ends of the cable to capture the PD signal. The fault is then located by comparing the propagation time difference between the captured PD signals at both ends. While this method can achieve meter-level positioning accuracy, it has significant application limitations.

[0069] Traditional two-end locating technology requires strong partial discharge (PD) signals to be detected at both ends for locating. In traditional two-end locating technology, a PD signal is typically identified only when the signal amplitude exceeds a threshold. If the threshold is too low, a large amount of noise signals can be mistaken for PD signals. Consequently, the sensitivity of PD locating is limited by the strength of the noise signal, resulting in low detection sensitivity. If the PD signal on the cable is weak or if there is significant on-site electromagnetic interference, resulting in the PD signal amplitude being lower than the noise signal amplitude, one end often detects the signal while the other fails to do so. In these situations, PD locating is impossible.

[0070] In an exemplary embodiment, a dual-terminal partial discharge location method is provided. This embodiment illustrates the method as applied to a terminal. The terminal may include, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices may include smart speakers, smart TVs, smart air conditioners, smart car devices, and projectors. Portable wearable devices may include smart watches, smart bracelets, and head-mounted devices. Head-mounted devices may include virtual reality (VR) devices, augmented reality (AR) devices, smart glasses, and the like. It is understood that the method can also be applied to servers and systems comprising terminals and servers, and implemented through interaction between the terminals and servers.

[0071] In some feasible embodiments, the method is applied to a dual-terminal partial discharge location system. A dual-terminal partial discharge location system can refer to a distributed measurement system for detecting and locating partial discharge in high-voltage power cables. Based on the principles of collaborative detection by multiple acquisition units and time difference calculation, it accurately locates the partial discharge site. The dual-terminal partial discharge location system includes at least a measurement host and multiple acquisition units, which exchange data and synchronize control with each other via a high-speed communication network.

[0072] The measurement host can coordinate the work of each acquisition unit to perform signal analysis, feature matching, and positioning calculations. The acquisition unit is a high-precision signal detection device deployed along the cable. The acquisition unit can collect raw pulse signals from the cable and monitor whether there are local discharge signals in the raw pulse signals. In some feasible embodiments, the acquisition unit can also be provided with a memory for storing the raw pulse signals collected by the terminal. The acquisition unit can be communicatively connected to the measurement host, thereby uploading at least one of the raw pulse signals collected by the terminal and related information of the raw pulse signals to the measurement host for signal analysis, feature matching, and positioning calculations.

[0073] In some feasible implementations, the terminal may refer to the measurement host, or may also refer to an external controller that controls the partial discharge dual-terminal positioning system.

[0074] In some feasible embodiments, the PD dual-terminal location system may further include a communication unit. This communication unit serves as the synchronization and data exchange hub for the PD dual-terminal location system, enabling time synchronization between acquisition units and reliable transmission of measurement data. A fiber-optic communication network can be used between the communication unit and the acquisition units to establish a low-latency, high-precision synchronization system, ensuring that the sampling clock deviation of each acquisition unit is less than 100 ns, meeting the accuracy requirements of dual-terminal location.

[0075] In some feasible implementations, the system architecture of the partial discharge dual-terminal positioning system is as follows: Figure 1 As shown in FIG, the partial discharge dual-terminal positioning system consists of a measurement host, a communication unit, multiple acquisition units, a high-frequency current sensor (HFCT, High-Frequency Current Transformer) and optical fiber.

[0076] Multiple cable joints can be set on the cable according to actual needs. The high-frequency current sensor is connected to the ground wire of the cable joint grounding box. The high-frequency current sensor corresponds to the acquisition unit one by one. The high-frequency current signal in the cable can be collected by the high-frequency current sensor. The acquisition unit can obtain the high-frequency current signal collected by the high-frequency current sensor and convert the obtained high-frequency current signal into an original pulse signal after impedance matching for partial discharge detection and positioning.

[0077] The communication unit is connected to each acquisition unit through optical fiber cascade, and the communication unit is connected to the measurement host through a network cable.

[0078] Each acquisition unit can be equipped with two dual-port RAMs (Random Access Memory), which are used to cache the pulse amplitude and pulse time of the original pulse signal respectively. The storage capacity of the RAM used to store the pulse amplitude can be 8192*16 bits, and the storage capacity of the RAM used to store the pulse time can be 8192*64 bits. When the two RAMs are cached simultaneously, the write addresses of the two RAMs are the same.

[0079] Figure 1The lightning mark in the middle indicates a partial discharge site, located on the cable segment between cable connector 1# and cable connector 2#. In this case, the partial discharge signal propagates along the cable to both ends and is captured by acquisition units 1 and 2, respectively. To avoid false detections, the acquisition units typically set an amplitude threshold higher than the noise signal amplitude and identify pulse signals with amplitudes exceeding this threshold as partial discharge signals. However, partial discharge signals attenuate during cable transmission, which can cause acquisition units farther away from the partial discharge site to capture partial discharge signals with amplitudes smaller than the noise signal—that is, smaller than the amplitude threshold, making them unrecognizable. Conventional technology, however, only captures partial discharge signals at one end, making it impossible to accurately locate the partial discharge site.

[0080] In this embodiment, Figure 2 As shown, the method includes the following steps S10-S40. In which:

[0081] Step S10: receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal whose signal amplitude exceeds a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, and the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected.

[0082] The acquisition unit may include a first acquisition unit and a second acquisition unit. The first acquisition unit may be an acquisition unit capable of acquiring and detecting a partial discharge signal. That is, when the partial discharge signal is transmitted to the first acquisition unit, its signal amplitude has not yet decayed below a preset amplitude threshold, and therefore can be identified. The second acquisition unit may be an acquisition unit adjacent to the first acquisition unit. If the first acquisition unit identifies a partial discharge signal but no other acquisition unit identifies the partial discharge signal, and if the transmission direction of the partial discharge signal cannot be determined, both second acquisition units adjacent to the first acquisition unit may upload a second discharge pulse frame.

[0083] The discharge pulse frame may refer to a data packet encapsulated by the acquisition unit from the detected original pulse signal and its related data. The discharge pulse frame may include structured data of at least one information such as a discharge waveform, a timestamp, and an amplitude.

[0084] A partial discharge location event can refer to a signal triggered by an acquisition unit, notifying adjacent acquisition units to initiate coordinated detection. For example, the partial discharge location event can be a trigger instruction. After a first acquisition unit detects a partial discharge signal whose amplitude exceeds a preset voltage threshold, it can send a trigger instruction to two adjacent second acquisition units. In response to the trigger instruction, the second acquisition units can retrieve the corresponding raw pulse signal from their own memory, generate a second discharge pulse frame, and upload the second discharge pulse frame.

[0085] For example, when a first acquisition unit detects a local discharge signal with an amplitude exceeding a preset voltage threshold, it can retrieve the corresponding original pulse signal from its own memory and generate a first discharge pulse frame based on the acquired original pulse signal. Simultaneously, a local discharge location event is triggered and sent to an adjacent second acquisition unit, notifying the adjacent second acquisition unit to initiate detection. In response to the local discharge location event, the adjacent second acquisition unit retrieves the corresponding original pulse signal from its own memory and generates a second discharge pulse frame based on the acquired original pulse signal. After generating the first discharge pulse frame, the first acquisition unit can upload the generated first discharge pulse frame to the terminal. After generating the second discharge pulse frame, the second acquisition unit can upload the generated second discharge pulse frame to the terminal. This active triggering mechanism ensures that multiple acquisition units can respond synchronously even when only one end can identify a local discharge signal.

[0086] In some feasible embodiments, the corresponding original pulse signal can be obtained from the memory of the terminal by: obtaining the original pulse signal within a preset time range before the current moment from the memory of the terminal; or obtaining the original pulse signal within a preset time range centered on the current moment from the memory of the terminal. If the original pulse signal after the current moment has not yet been collected, it can be uploaded in real time during collection. For example, assuming the current moment is T1 and the preset time range is 2t, the original pulse signal collected from the time period T1-2t to T1 can be obtained from the memory of the terminal, or the original pulse signal collected from the time period T1-t to T1+t can be obtained from the memory of the terminal.

[0087] Step S20 , locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal.

[0088] The peak moment may refer to the time point at which the pulse signal reaches the maximum amplitude.

[0089] As an example, after obtaining the first discharge pulse frame, the local discharge signal can be parsed from the first discharge pulse frame, and then the peak detection algorithm is used to detect the highest amplitude point of the local discharge signal, and its corresponding timestamp is recorded as the first peak moment, wherein the peak detection algorithm can be a sliding window extreme value search, etc.

[0090] As another example, after obtaining the first discharge pulse frame, the peak detection algorithm can also be directly used to detect the highest amplitude point of the first discharge pulse frame, and the pulse waveform corresponding to the highest amplitude point can be determined as the pulse waveform of the local discharge signal in the first discharge pulse frame, and the timestamp corresponding to the highest amplitude point can be recorded as the first peak moment, wherein the peak detection algorithm can be a sliding window extreme value search, etc.

[0091] In some feasible implementations, the pulse waveform corresponding to the highest amplitude point may refer to a pulse waveform determined to include a preset number of data points centered at the highest amplitude point. For example, assuming the highest amplitude point is the Nth data point and the preset number is n, the pulse waveform corresponding to the highest amplitude point may be composed of data points from the Nnth data point to the N+nth data point.

[0092] Step S30 , extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal.

[0093] The characteristic information may refer to at least one of time domain parameters and frequency domain parameters extracted from the pulse signal. For example, the characteristic information may include at least one recognizable characteristic quantity such as pulse rise time, oscillation frequency, waveform envelope, etc.

[0094] Illustratively, after obtaining the first discharge pulse frame and the second discharge pulse frame, feature extraction can be performed on the pulse waveform of the local discharge signal in the first discharge pulse frame to obtain feature information. Then, in the second discharge pulse frame, through correlation analysis or pattern matching algorithm, etc., the pulse waveform that best matches the feature information is screened out, and the pulse waveform is determined as the pulse waveform of the local discharge signal in the second discharge pulse frame, and the peak moment of the pulse waveform is determined as the second peak moment.

[0095] In this way, even if the amplitude of the pulse waveform of the partial discharge signal in the first discharge pulse frame is small and lower than the preset voltage threshold and cannot be directly identified as a partial discharge signal, it can still be identified through feature matching, thereby achieving dual-end positioning of lower-intensity partial discharge signals and improving the detection sensitivity of partial discharge dual-end positioning.

[0096] Step S40 : determining a partial discharge position based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0097] The cable positioning information may be used to characterize the physical position of the acquisition unit on the cable line. For example, the cable positioning information may be the length coordinate of the distance between the acquisition unit and the starting point of the cable.

[0098] For example, based on the first cable positioning information corresponding to the first acquisition unit and the second cable positioning information corresponding to the second acquisition unit, the cable length between the first and second acquisition units can be calculated. Based on the first and second peak moments, the time difference between the two peak moments can be calculated, and the discharge location can then be calculated using the traveling wave ranging principle. For example, the partial discharge location = (Lv × Δt) / 2, where L is the cable length between the two units, v is the propagation velocity of the partial discharge signal in the cable, and Δt is the time difference between the two peak moments.

[0099] In the above-mentioned partial discharge dual-terminal locating method, a first discharge pulse frame is first received by a first acquisition unit, and a second discharge pulse frame is first received by at least one second acquisition unit adjacent to the first acquisition unit. The first discharge pulse frame includes a partial discharge signal whose signal amplitude exceeds a preset voltage threshold. The second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event. The partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected. This achieves single-end triggering of the partial discharge dual-terminal locating method. That is, as long as any acquisition unit recognizes the partial discharge signal, the acquisition unit that recognizes the partial discharge signal and its adjacent acquisition units can transmit the partial discharge signal. The method comprises the steps of: locating the local discharge signal from the first discharge pulse frame to obtain the first peak moment of the local discharge signal, extracting characteristic information of the local discharge signal from the first discharge pulse frame, locating the local discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining the second peak moment of the local discharge signal. This method realizes capturing the local discharge signal from the second discharge pulse frame with a weaker signal or stronger noise, thereby determining the moment when the local discharge signal is collected by both ends; and determining the local discharge position based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment. This method can realize dual-end positioning of the local discharge.

[0100] In this way, if the PD signal from the cable itself is weak or the environmental interference is significant, preventing one end from identifying the PD signal, the end that can identify the PD signal can trigger the upload of a discharge pulse frame. Feature information is extracted from the first PD pulse frame with a stronger PD signal, and based on this feature information, the PD signal is identified in the second PD pulse frame with a weaker PD signal. This solution enables dual-end positioning of even weaker PD signals, significantly improving detection reliability in weak signal scenarios and overcoming the technical drawback of traditional methods, where positioning fails due to single-end signal loss.

[0101] In an exemplary embodiment, Figure 3 As shown, the method is applied to a partial discharge dual-terminal locating system, which includes a measurement host and multiple acquisition units, each of which includes a first acquisition unit and at least one second acquisition unit adjacent to the first acquisition unit. Before receiving the first discharge pulse frame sent by the first acquisition unit, the partial discharge dual-terminal locating method further includes steps S02 to S06. Among them:

[0102] Step S02: When a partial discharge signal with a signal amplitude exceeding a preset voltage threshold is detected by the first acquisition unit, a partial discharge location event is triggered. The partial discharge detection time corresponding to the partial discharge signal is determined based on a network-wide synchronization time accumulation counter, and the partial discharge detection time and the partial discharge location event are sent to each second acquisition unit.

[0103] The network-wide synchronized time accumulation counter can be a high-precision clock source that continuously accumulates time with nanosecond resolution. Each acquisition unit can be deployed with a network-wide synchronized time accumulation counter. The error between the network-wide synchronized time accumulation counters of each acquisition unit should be less than 10 nanoseconds. In some feasible implementations, the error between the network-wide synchronized time accumulation counters of each acquisition unit can be less than 3 nanoseconds.

[0104] The partial discharge detection moment may refer to a precise timestamp latched by a network-wide synchronized time accumulation counter when a signal amplitude exceeding a preset voltage threshold is detected.

[0105] For example, when the first acquisition unit detects that the signal amplitude of any pulse signal exceeds a preset voltage threshold, a partial discharge location event is immediately triggered. At this time, the network-wide synchronous time accumulation counter inside the first acquisition unit can latch the current count value to generate an accurate partial discharge detection moment. Subsequently, the first acquisition unit broadcasts this partial discharge detection moment and partial discharge location event to the second acquisition unit adjacent to the first acquisition unit via a synchronous optical cable or high-speed Ethernet.

[0106] Step S04 : obtaining a plurality of first discharge waveform values corresponding to the partial discharge detection moment from the local end memory via the first acquisition unit, generating a first discharge pulse frame based on each first discharge waveform value, and uploading the first discharge pulse frame to the measurement host.

[0107] The first discharge waveform value may refer to an original voltage sampling sequence corresponding to the partial discharge detection moment, extracted from the memory on the first acquisition unit.

[0108] For example, upon detecting a partial discharge signal with a signal amplitude exceeding a preset voltage threshold, the first acquisition unit extracts multiple first discharge waveform values corresponding to the partial discharge detection moment from a local memory. For example, assuming the partial discharge detection moment is T1, multiple sampling points within the range of T1-200ns to T1+200ns may be extracted. Furthermore, the first acquisition unit may generate a first discharge pulse frame based on these first discharge waveform values and their corresponding partial discharge detection moments, and upload the frame to the measurement host via an optical fiber.

[0109] The multiple first discharge waveform values corresponding to the partial discharge detection moment may refer to determining the multiple first discharge waveform values by limiting the range of the first discharge waveform values with the partial discharge detection moment as the center value and by limiting the range of the first discharge waveform values with a preset time range or a preset data amount.

[0110] Step S06 , in response to the partial discharge location event, the second acquisition unit obtains multiple second discharge waveform values corresponding to the partial discharge detection moment from the local end memory, generates a second discharge pulse frame based on each second discharge waveform value, and uploads the second discharge pulse frame to the measurement host.

[0111] The second discharge waveform value may refer to an original voltage sampling sequence corresponding to the partial discharge detection moment, extracted from the memory on the second acquisition unit.

[0112] For example, upon receiving the partial discharge location time and partial discharge detection moment, the second acquisition unit can immediately retrieve multiple second discharge waveform values corresponding to the partial discharge detection moment from its local memory. For example, assuming the partial discharge detection moment is T1, multiple sampling points within the range of T1-200ns to T1+200ns can be extracted. Furthermore, the second acquisition unit can generate a second discharge pulse frame based on these second discharge waveform values and their corresponding partial discharge detection moments, and upload the frame to the measurement host via optical fiber.

[0113] The multiple second discharge waveform values corresponding to the partial discharge detection moment may refer to determining the multiple second discharge waveform values by limiting the range of the second discharge waveform values with the partial discharge detection moment as the center value and using a preset time range or a preset data amount.

[0114] In this embodiment, threshold detection by the first acquisition unit rapidly identifies partial discharge signals and immediately activates the adjacent second acquisition unit, enabling the dual-terminal partial discharge location system to capture weak signals that traditional methods might miss. Furthermore, timestamp alignment using a network-wide synchronized time accumulation counter ensures strict synchronization of multi-terminal signals, eliminating location errors caused by cable transmission delays.

[0115] In an exemplary embodiment, obtaining a plurality of first discharge waveform values corresponding to the partial discharge detection moment from a memory of the local end includes:

[0116] The first write address corresponding to the partial discharge detection moment is searched from the memory of the first acquisition unit; a first write address segment is determined based on the first write address and a preset first signal quantity; and multiple first discharge waveform values in the first write address segment are obtained.

[0117] The first write address may refer to a write location of data written into the memory of the first acquisition unit at the time of partial discharge detection.

[0118] The preset first signal quantity may refer to the quantity of pulse waveform data to be extracted, which may be determined in advance based on signal characteristics and actual conditions, and is not limited in this embodiment.

[0119] The first write address segment may refer to a continuous memory region corresponding to a preset first signal number of sampling points of the first write address. The first write address segment includes the first write address, and the first write address may be located at the end or in the middle of the first write address segment. The specific location may be determined based on actual circumstances and is not limited in this embodiment.

[0120] Illustratively, after determining the partial discharge detection moment, the first acquisition unit may immediately obtain the first write address corresponding to the partial discharge detection moment from the write address pointer register of the local memory; further, based on a preset number of first signals, the first write address segment may be calculated with the first write address as the end point or midpoint; further, multiple first discharge waveform values may be read sequentially from the memory area corresponding to the first write address segment.

[0121] Acquiring multiple second discharge waveform values corresponding to the partial discharge detection moment from the memory of the local end, including:

[0122] The second write address corresponding to the partial discharge detection moment is searched from the memory of the second acquisition unit; a second write address segment is determined based on the second write address and a preset second signal quantity; and multiple second discharge waveform values in the second write address segment are read.

[0123] The first write address may refer to a write location of data written into the memory of the first acquisition unit at the time of partial discharge detection.

[0124] The preset second signal quantity may refer to the quantity of pulse waveform data to be extracted, which may be determined in advance based on signal characteristics and actual conditions, and is not limited in this embodiment.

[0125] The second write address segment may refer to a continuous memory region corresponding to a preset second signal number of sampling points of the second write address. The second write address segment includes the second write address, and the second write address may be located at the end or in the middle of the second write address segment. The specific location may be determined based on actual circumstances and is not limited in this embodiment.

[0126] Illustratively, after determining the partial discharge detection moment, the second acquisition unit may immediately obtain the second write address corresponding to the partial discharge detection moment from the write address pointer register of the local memory; further, based on a preset number of second signals, the second write address segment may be calculated with the second write address as the end point or midpoint; further, multiple second discharge waveform values may be read sequentially from the memory area corresponding to the second write address segment.

[0127] In this embodiment, when the first acquisition unit detects a discharge signal, it can immediately lock the first write address of the memory through the timestamp and intelligently trace back the corresponding first write address segment based on the preset first signal quantity, thereby completely extracting the original pulse signal containing the partial discharge signal.

[0128] In an exemplary embodiment, the partial discharge dual-terminal locating system further includes a communication unit, wherein the communication unit and each acquisition unit are cascaded via a data transmission line. Before determining the partial discharge detection time corresponding to the partial discharge signal based on the network-wide synchronized time accumulation counter, the partial discharge dual-terminal locating method further includes:

[0129] Step S011 : sending test data to corresponding subsequent units via respective preceding units, wherein the preceding units include a communication unit and at least one of the acquisition units, and the subsequent units include at least one of the acquisition units.

[0130] Among them, the communication unit and each collection unit are connected step by step in series through a data transmission line to form a continuous data transmission link. Among them, the data transmission line can refer to an optical fiber or a high-speed Ethernet cable, etc. For example, the communication unit can be used as the main node and connected to the first collection unit, and the collection unit is then connected to the second collection unit through a downlink interface, and then extended in series to the last collection unit. Synchronous instructions and trigger signals can be transmitted step by step from the communication unit to the collection unit from top to bottom, and the collected data can be summarized step by step from the collection unit to the communication unit from bottom to top. The cascade design perfectly matches the characteristics of the linear distribution of power cables. It is a cost-effective solution for long-distance partial discharge dual-end positioning systems. Its value is particularly prominent in narrow and long scenes such as tunnels and pipe corridors.

[0131] The preceding unit and the following unit are relative concepts. For any communication unit or acquisition unit, the communication unit or acquisition unit at the previous level is its preceding unit, and the acquisition unit at the next level is its following unit.

[0132] The test data may refer to a periodic square wave signal used for clock calibration.

[0133] For example, network-wide time synchronization can be performed periodically before or during partial discharge monitoring. Specifically, test data can be sent to a subsequent acquisition unit via a communication unit. The test data is transmitted serially over a data transmission line. Before transmission, the test data can be 8B10B encoded to ensure that the data contains sufficient clock edge information.

[0134] In step S012 , each subsequent unit dynamically adjusts its corresponding voltage-controlled crystal oscillator based on the number of clock edges of the received test data, so that the clock frequency and phase of adjacent subsequent units are consistent with those of the previous unit.

[0135] The number of clock edge times may refer to the number of rising edges or falling edges of a signal detected within a unit time.

[0136] A voltage-controlled crystal oscillator (VCO) is a crystal oscillator whose output frequency can be adjusted by voltage.

[0137] For example, after the test data enters the subsequent unit, it can first pass through a serial processing channel composed of an even number of fixed delay units, and the delay time of each stage is precisely set to an equal division of the voltage-controlled crystal oscillator period; in each clock cycle, the system detects the output signals of all delay stages in parallel, accurately determines the specific position of the clock edge in the delay chain, and when the edge appears in the first half of the delay stage, the edge change counter automatically increments, and when it appears in the second half, it decrements. When the counter reaches the extreme value, it resets to the middle value and outputs the crystal oscillator adjustment signal; through this closed-loop control mechanism, the voltage-controlled crystal oscillator is continuously and dynamically adjusted, and the clock edge is finally stably locked in the center position of the delay chain, thereby ensuring that the subsequent unit and the previous unit maintain strict frequency and phase synchronization, and the synchronization accuracy can reach the nanosecond level.

[0138] In step S013, each preceding unit sends a delay measurement frame to its corresponding succeeding unit, and receives feedback information returned by its corresponding succeeding unit in response to the delay measurement frame, and calculates the transmission delay between each preceding unit and its corresponding succeeding unit based on the feedback information.

[0139] The delay measurement frame may refer to a marker data packet used to measure link transmission delay.

[0140] For example, when the clock frequencies and phases of adjacent units are aligned, the communication unit can send a delay measurement frame to the subsequent acquisition unit. The delay measurement frame is transmitted serially on the data transmission line. The preceding unit sends the delay measurement frame and records the sending time. After receiving the delay measurement frame, the subsequent unit records the reception time and, when the timing reaches the preset waiting time, returns feedback information to the preceding unit. The feedback information includes the reception time and the preset waiting time. The preceding unit can then calculate the one-way transmission delay based on the received reception time and the preset waiting time, as well as the sending time.

[0141] In some feasible implementations, step S013 may be repeated multiple times until the measurement results of multiple consecutive measurements are consistent or the error is less than a preset error, and the precise transmission delay duration is stored in the front-end unit.

[0142] Step S014, starting from the communication unit, the whole network synchronization time frame is issued to each acquisition unit step by step. Each whole network synchronization time frame includes the whole network synchronization timestamp of the previous unit and the transmission delay duration calculated by the previous unit. The whole network synchronization time frame is used to update the whole network synchronization timestamp of the receiving end. The error between the whole network synchronization timestamps updated by each acquisition unit is less than the preset error threshold.

[0143] The network-wide synchronized timestamp may refer to an absolute time reference based on the master clock of the communication unit.

[0144] The network-wide synchronization time frame may refer to a data packet carrying a network-wide synchronization timestamp and a transmission delay duration.

[0145] For example, after determining the transmission delay, a network-wide synchronization time frame can be sent downwards, starting with the communication unit. After receiving the network-wide synchronization time frame, each subsequent unit can extract the network-wide synchronization timestamp and transmission delay duration of the previous unit from the network-wide synchronization time frame. The network-wide synchronization timestamp can then be updated by adding the transmission delay duration to the previous unit's network-wide synchronization timestamp. The transmission delay duration from the current level to the next level can then be added, and the updated network-wide synchronization time frame can be sent downwards.

[0146] In this embodiment, by dynamically controlling the voltage-controlled crystal oscillator, the clocks of all serially connected acquisition units can have consistent frequencies and phases; by measuring the delay frame, the transmission delay value between adjacent units can be obtained; through network-wide synchronization time frame processing, each acquisition unit will obtain consistent network-wide synchronization time, and the system will achieve high-precision time synchronization, thereby effectively improving the partial discharge measurement effect and partial discharge positioning accuracy.

[0147] In an exemplary embodiment, locating the partial discharge signal from the first discharge pulse frame to obtain the first peak moment of the partial discharge signal includes steps S21 to S23.

[0148] Step S212: Acquire a first start timestamp of the first discharge pulse frame and a second start timestamp of each second discharge pulse frame.

[0149] The first start timestamp may refer to the timestamp corresponding to the first pulse waveform in the first discharge pulse frame, and the second start timestamp may refer to the timestamp corresponding to the first pulse waveform in the second discharge pulse frame.

[0150] For example, after obtaining the first discharge pulse frame, the pulse waveform can be identified starting from the earliest moment of the first discharge pulse frame, and the timestamp corresponding to the identified first pulse waveform can be determined as the first starting timestamp of the first discharge pulse frame; after obtaining the second discharge pulse frame, the pulse waveform can be identified starting from the earliest moment of the second discharge pulse frame, and the timestamp corresponding to the identified second pulse waveform can be determined as the second starting timestamp of the second discharge pulse frame.

[0151] Step S22: Detect the start time difference between the first start timestamp and each second start timestamp.

[0152] The start time difference may refer to the absolute time difference between the start timestamps of two discharge pulse frames.

[0153] Exemplarily, after determining the first start timestamp and the second start timestamp, a start time difference between the first start timestamp and each second start timestamp may be calculated.

[0154] Step S23: When at least one of the start time differences is less than a corresponding preset time difference threshold, locating the partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal, wherein the preset time difference threshold is determined based on the communication distance and cable length corresponding to the start time difference.

[0155] The preset time difference threshold may refer to a maximum allowable time difference calculated according to the communication distance and the cable length.

[0156] For example, if any of the start time differences is less than a preset time difference threshold, the target second discharge pulse frame and the target second acquisition unit corresponding to the start time difference less than the preset time difference threshold can be further determined. This can be used to determine that the target second discharge pulse frame and the first discharge pulse frame originate from the same discharge event. In other words, it can be determined that the target second discharge pulse frame contains a partial discharge signal. In this case, the partial discharge signal can be located within the first discharge pulse frame to obtain the first peak moment of the partial discharge signal.

[0157] If the start time differences are both greater than a preset time difference threshold, it can be determined that the second discharge pulse frame and the first discharge pulse frame do not originate from the same discharge event, and there is a high probability that the second discharge pulse frame does not contain a partial discharge signal. To avoid subsequent invalid detection processes, the currently acquired first and second discharge pulse frames can be discarded, and the process returns to the step of receiving the first discharge pulse frame sent by the first acquisition unit and the second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit. In the presence of partial discharge, partial discharge signals will continue to be generated and can also be continuously acquired by the acquisition unit.

[0158] In this embodiment, the accuracy and real-time performance of discharge signal correlation can be effectively improved by synergizing timestamp comparison and threshold judgment. Peak detection is initiated only when the time difference meets the requirement, thus avoiding false triggering due to noise and saving computing resources.

[0159] In an exemplary embodiment, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information to obtain the second peak moment of the partial discharge signal includes steps S31 to S32.

[0160] Step S31 : performing feature recognition on the second discharge pulse frame based on the feature information.

[0161] For example, after extracting the characteristic information of the partial discharge signal, feature recognition can be performed on the second discharge pulse frame based on the characteristic information to determine whether the second discharge pulse frame contains a partial discharge signal. The specific method of feature recognition is similar to that of the prior art and is not further described in this embodiment.

[0162] In some feasible embodiments, the method of performing feature recognition on the second discharge pulse frame based on the characteristic information can be: determining the data amount of the second discharge pulse frame as the window length, starting from the second starting timestamp of the second discharge pulse frame, intercepting the first window data, and comparing the first window data with the characteristic information; if the similarity between the two is higher than the preset similarity threshold, it can be considered that the pulse waveform corresponding to the first window data is the pulse waveform corresponding to the local discharge signal, and the feature recognition ends; if the similarity between the two is not higher than the preset similarity threshold, it can be considered that the pulse waveform corresponding to the first window data is not the pulse waveform corresponding to the local discharge signal, and the window can be slid based on the preset sliding step size to intercept the next window data, and compare the next window data with the characteristic information, and the window data is updated in this way until a pulse waveform with a similarity higher than the preset similarity threshold is detected, or the sliding window reaches the end timestamp of the second discharge pulse frame.

[0163] If no pulse waveform with a similarity higher than a preset similarity threshold is detected by the sliding window until the end timestamp of the second discharge pulse frame is reached, it can be determined that the second discharge pulse frame does not contain a pulse waveform corresponding to a partial discharge signal. The partial discharge signal may exist on the other side of the first acquisition unit.

[0164] Based on the feature information extracted from the first discharge pulse frame (such as a rising edge of 3ns and an oscillation frequency of 12MHz), the second discharge pulse frame is segmented and identified. A time-frequency joint analysis algorithm (such as dynamic time warping (DTW) or wavelet correlation coefficient) is used to calculate the similarity score between each candidate waveform segment in the second frame and the feature template. When the similarity of a waveform segment exceeds a preset similarity threshold (such as 0.85), it is marked as the target signal waveform, and interpolation is used to accurately locate the corresponding moment of its peak point (for example, the peak is identified at timestamp T2+18ns), and this moment is ultimately determined as the second peak moment.

[0165] Step S32 , when a target signal waveform having a similarity with the characteristic information higher than a preset similarity threshold is identified from the second discharge pulse frame, the peak moment of the target signal waveform is determined as the second peak moment of the partial discharge signal.

[0166] The similarity threshold may refer to a minimum similarity score used to determine waveform correlation. If the similarity between two waveforms is higher than the similarity threshold, it can be considered that the waveforms at both ends are formed by the same discharge source. This can be determined based on experience or test results, and is not limited in this embodiment.

[0167] For example, when it is identified that the similarity between a certain waveform and the characteristic information exceeds a preset similarity threshold, it can be marked as a target signal waveform, and the peak moment corresponding to the peak point of the target signal waveform can be accurately located, and the peak moment can be determined as the second peak moment of the partial discharge signal.

[0168] In this embodiment, the traditional amplitude trigger is replaced by feature matching, which can significantly improve the weak signal recognition rate, thereby improving the sensitivity of partial discharge dual-terminal positioning.

[0169] In some feasible embodiments, the partial discharge dual-terminal location method is applied to a partial discharge dual-terminal location system, which consists of a measurement host, a communication unit, several partial discharge acquisition units, several high-frequency current sensors, and optical fibers. Cable connectors are provided at intervals on the cable, with a one-to-one correspondence between the cable connectors, high-frequency current sensors, and acquisition units. The high-frequency current sensors are connected to the ground wire of each cable connector grounding box and transmit the collected data to the corresponding acquisition unit. The communication unit and the acquisition units achieve full network synchronization via optical fiber. Each acquisition unit has a 64-bit full-network synchronization time accumulation counter, and the error between the full-network synchronization time accumulation counters of each acquisition unit is less than 3. Each acquisition unit has two dual-port RAMs for caching pulse amplitude and pulse time, respectively: 8192*16 bits of pd_wave_ram and 8192*64 bits of pd_time_ram. Because the two RAMs are cached simultaneously, the write addresses of the two RAMs are the same.

[0170] For ease of understanding, the end where partial discharge is detected is called the master end, and the end where partial discharge is not detected is called the slave end.

[0171] The partial discharge two-terminal location method includes:

[0172] The master end identifies the partial discharge signal based on the voltage threshold and records the write address at the time the partial discharge signal is identified, recorded as pd_time_ram_trig_wr_addr1. It also records the write data at the time the partial discharge signal is identified, recorded as pd_time_ram_trig_time1.

[0173] The master end reads the pulse amplitude corresponding to the address segment greater than pd_time_ram_trig_wr_addr1-1024 and less than pd_time_ram_trig_wr_addr1+1024 from pd_wave_ram, with pd_time_ram_trig_wr_addr1 as the center, to form a discharge waveform value containing 2048 data points; and reads the pulse time corresponding to the address segment greater than pd_time_ram_trig_wr_addr1-1024 and less than pd_time_ram_trig_wr_addr1+1024 from pd_time_ram, to obtain the timestamps corresponding to the discharge waveform values of 2048 data points, and marks the first timestamp read from pd_time_ram as the start time start_tim1 of the master end discharge pulse, and forms a discharge pulse frame together with the 2048-point discharge waveform values read from pd_wave_ram; then, the master end uploads the generated discharge pulse frame to the measurement host.

[0174] The master end transmits pd_time_ram_trig_time1 to the slave end through the optical fiber. The slave end reads the entire pd_time_ram and finds the write address corresponding to the value of pd_time_ram_trig_time1, which is recorded as pd_time_ram_trig_wr_addr2.

[0175] The slave end takes pd_time_ram_trig_wr_addr2 as the center and reads the pulse amplitude corresponding to the address segment greater than pd_time_ram_trig_wr_addr2-1024 and less than pd_time_ram_trig_wr_addr2+1024 from pd_wave_ram to form a discharge waveform value containing 2048 data points; reads the pulse time corresponding to the address segment greater than pd_time_ram_trig_wr_addr2-1024 and less than pd_time_ram_trig_wr_addr2+1024 from pd_time_ram to obtain the timestamps corresponding to the discharge waveform values of 2048 data points, and marks the first timestamp read from pd_time_ram as the start time start_tim2 of the slave end discharge pulse, and forms a discharge pulse frame together with the 2048-point discharge waveform values read from pd_wave_ram; then, the slave end uploads the generated discharge pulse frame to the measurement host.

[0176] The measurement host first analyzes the discharge pulse frame uploaded by the master end, finds the peak position of the partial discharge signal, records it as p1, and marks the peak timestamp of the master end partial discharge signal T1=pd_time_trig_start_time1+p1.

[0177] The measuring host takes 32 points around the peak position of the partial discharge signal to form a 64-point partial discharge signal and extracts characteristic parameters.

[0178] Then, the measurement host analyzes the discharge pulse frame uploaded by the slave end, intercepts the window data from the discharge pulse frame uploaded by the slave end according to the sliding step size of 4 data points and the sliding window length of 64 data points, extracts the feature information from the intercepted window data, and calculates the correlation with the feature information extracted by the master end. The window data with the strongest correlation with the feature information extracted by the master end is found, and the peak position is recorded as p2. Finally, the peak time stamp of the partial discharge signal at the slave end is marked as T2=pd_time_trig_start_time2+p2. The pulse waveforms of the master and slave ends are shown as follows: Figure 4 As shown, Figure 4 The upper middle part is the pulse waveform corresponding to the discharge pulse frame uploaded by the master end. Figure 4 The lower middle portion is a pulse waveform corresponding to the discharge pulse frame uploaded from the terminal.

[0179] The measurement host calculates the time difference between the peak values of the partial discharge signals at the master and slave ends to be equal to the absolute value of (T1-T2), recorded as ΔT. Given the distance L between the master and slave cables and the propagation velocity V of the partial discharge signal in the cable, the distance from the master end to the partial discharge signal can be calculated to be (L-ΔT*V) / 2, thereby locating partial discharge faults in the power cable itself.

[0180] The high-frequency current sensor is connected to the ground wire of the grounding box near the cable connector. The detected partial discharge signals from the cable body are not necessarily strong partial discharge signals. Often, only one end can detect partial discharge signals, such as cable body ablation. In this case, using conventional two-end positioning technology, it is generally difficult to locate partial discharge faults in the cable body. However, if the two-end positioning method of this embodiment is adopted, it can efficiently locate weak partial discharges in the cable body, especially partial discharges caused by cable body ablation, thereby effectively avoiding cable failures caused by cable body ablation.

[0181] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0182] Based on the same inventive concept, embodiments of the present application further provide a partial discharge dual-terminal locating device for implementing the aforementioned partial discharge dual-terminal locating method. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the partial discharge dual-terminal locating device provided below can be found in the aforementioned limitations of the partial discharge dual-terminal locating method and are not further elaborated here.

[0183] In an exemplary embodiment, Figure 5 As shown, a partial discharge dual-terminal positioning device is provided, comprising: a receiving module 502, a first positioning module 504, a second positioning module 506 and a determining module 508, wherein:

[0184] a receiving module 502 configured to receive a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge location event, wherein the partial discharge location event is triggered by the first acquisition unit upon detecting the partial discharge signal;

[0185] A first positioning module 504 is configured to locate the partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal;

[0186] A second positioning module 506 is configured to extract characteristic information of the partial discharge signal from the first discharge pulse frame, locate the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtain a second peak moment of the partial discharge signal;

[0187] The determination module 508 is configured to determine a partial discharge location based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

[0188] In an exemplary embodiment, the device is applied to a partial discharge dual-terminal locating system, which includes a measurement host and multiple acquisition units, each of which includes a first acquisition unit and at least one second acquisition unit adjacent to the first acquisition unit. The device also includes an acquisition module. Before receiving a first discharge pulse frame sent by the first acquisition unit, the acquisition module is further configured to:

[0189] When a partial discharge signal with a signal amplitude exceeding a preset voltage threshold is detected by the first acquisition unit, a partial discharge location event is triggered, a partial discharge detection time corresponding to the partial discharge signal is determined based on a network-wide synchronized time accumulation counter, and the partial discharge detection time and the partial discharge location event are sent to each second acquisition unit;

[0190] Acquiring, by a first acquisition unit, a plurality of first discharge waveform values corresponding to the partial discharge detection moment from a memory of the local end, generating a first discharge pulse frame based on each first discharge waveform value, and uploading the first discharge pulse frame to a measurement host;

[0191] In response to a partial discharge location event, the second acquisition unit obtains multiple second discharge waveform values corresponding to the partial discharge detection moment from the local end memory, generates a second discharge pulse frame based on each second discharge waveform value, and uploads the second discharge pulse frame to the measurement host.

[0192] In an exemplary embodiment, the acquisition module is further configured to:

[0193] querying a first write address corresponding to the partial discharge detection moment from a memory at a local end of the first acquisition unit;

[0194] determining a first write address segment based on the first write address and a preset first signal quantity;

[0195] Taking a plurality of first discharge waveform values in a first write address segment;

[0196] querying a second write address corresponding to the partial discharge detection moment from a memory at a local end of the second acquisition unit;

[0197] determining a second write address segment based on the second write address and a preset second signal quantity;

[0198] A plurality of second discharge waveform values in the second write address segment are read.

[0199] In an exemplary embodiment, the partial discharge dual-terminal location system further includes a communication unit, wherein the communication unit and each acquisition unit are cascaded via a data transmission line; before determining the partial discharge detection time corresponding to the partial discharge signal based on the network-wide synchronized time accumulation counter, the acquisition module is further configured to:

[0200] Sending test data to the corresponding subsequent units through each preceding unit, wherein the preceding unit includes a communication unit and at least one of the acquisition units, and the subsequent unit includes at least one of the acquisition units;

[0201] Dynamically adjust the voltage-controlled crystal oscillator (VCO) of each subsequent unit based on the number of clock edges of the received test data, so that the clock frequency and phase of the adjacent subsequent units are consistent with those of the previous units.

[0202] Sending a delay measurement frame to the corresponding subsequent unit through each preceding unit, receiving feedback information returned by the corresponding subsequent unit in response to the delay measurement frame, and calculating the transmission delay between each preceding unit and the corresponding subsequent unit based on the feedback information;

[0203] Starting from the communication unit, the whole network synchronization time frame is issued to each acquisition unit step by step. Each whole network synchronization time frame includes the whole network synchronization timestamp of the previous unit and the transmission delay calculated by the previous unit. The whole network synchronization time frame is used to update the whole network synchronization timestamp of the receiving end. The error between the whole network synchronization timestamps updated by each acquisition unit is less than the preset error threshold.

[0204] In an exemplary embodiment, the first positioning module 504 is further configured to:

[0205] Acquire a first starting timestamp of a first discharge pulse frame and a second starting timestamp of each second discharge pulse frame;

[0206] Detecting a start time difference between the first start timestamp and each second start timestamp;

[0207] When at least one start time difference is less than a corresponding preset time difference threshold, a partial discharge signal is located from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal, wherein the preset time difference threshold is determined based on a communication distance and a cable length corresponding to the start time difference.

[0208] In an exemplary embodiment, the second positioning module 506 is further configured to:

[0209] performing feature recognition on the second discharge pulse frame based on the feature information;

[0210] When a target signal waveform having a similarity with the characteristic information higher than a preset similarity threshold is identified from the second discharge pulse frame, the peak moment of the target signal waveform is determined as the second peak moment of the partial discharge signal.

[0211] Each module in the aforementioned partial discharge dual-terminal locating device can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a computer device's memory in the form of software, so that the processor can call and execute the corresponding operations of each module.

[0212] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 6As shown. The computer device includes a processor, memory, an input / output interface, a communication interface, a display unit, and an input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals via wired or wireless means, and the wireless means can be implemented via Wi-Fi, a mobile cellular network, near-field communication (NFC), or other technologies. When executed by the processor, the computer program implements a method for two-terminal localization of partial discharges. The display unit of the computer device is used to form a visually visible image, and can be a display screen, a projection device, or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device casing, or an external keyboard, touchpad or mouse.

[0213] Those skilled in the art will understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0214] In one embodiment, a computer device is further provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0215] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0216] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0217] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0218] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to a memory, database, or other medium used in the embodiments provided in this application can include at least one of a non-volatile memory and a volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0219] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0220] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A partial discharge double-terminal positioning method, characterized in that: The method comprises: receiving a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, wherein the partial discharge locating event is triggered by the first acquisition unit when the partial discharge signal is detected; Locating the partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal; extracting characteristic information of the partial discharge signal from the first discharge pulse frame, locating the partial discharge signal from the second discharge pulse frame based on the characteristic information, and obtaining a second peak moment of the partial discharge signal; A partial discharge position is determined based on the first cable positioning information corresponding to the first acquisition unit, the second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

2. The method according to claim 1, characterized in that The method is applied to a partial discharge dual-terminal positioning system, which includes a measurement host and multiple acquisition units, wherein the acquisition units include a first acquisition unit and at least one second acquisition unit adjacent to the first acquisition unit; Before receiving the first discharge pulse frame sent by the first acquisition unit, the method further includes: triggering, by the first acquisition unit, a partial discharge location event when a partial discharge signal having a signal amplitude exceeding a preset voltage threshold is detected, determining a partial discharge detection time corresponding to the partial discharge signal based on a network-wide synchronization time accumulation counter, and transmitting the partial discharge detection time and the partial discharge location event to each of the second acquisition units; Acquiring, by the first acquisition unit, a plurality of first discharge waveform values corresponding to the partial discharge detection moment from a memory of the local end, generating a first discharge pulse frame based on each of the first discharge waveform values, and uploading the first discharge pulse frame to the measurement host; In response to the partial discharge location event, the second acquisition unit obtains multiple second discharge waveform values corresponding to the partial discharge detection moment from the local end memory, generates a second discharge pulse frame based on each second discharge waveform value, and uploads the second discharge pulse frame to the measurement host.

3. The method according to claim 2, characterized in that The acquiring, from the memory of the local end, a plurality of first discharge waveform values corresponding to the partial discharge detection moment includes: querying a first write address corresponding to the partial discharge detection moment from a memory on the local end of the first acquisition unit; determining a first write address segment based on the first write address and a preset first signal quantity; Taking a plurality of first discharge waveform values in the first write address segment; The acquiring, from the memory of the local end, a plurality of second discharge waveform values corresponding to the partial discharge detection moment includes: querying a second write address corresponding to the partial discharge detection moment from a memory on the local end of the second acquisition unit; determining a second write address segment based on the second write address and a preset second signal quantity; A plurality of second discharge waveform values in the second write address segment are read.

4. The method according to claim 2, characterized in that The partial discharge dual-terminal positioning system further includes a communication unit, wherein the communication unit and each of the acquisition units are cascaded via a data transmission line; Before determining the partial discharge detection time corresponding to the partial discharge signal based on the network-wide synchronization time accumulation counter, the method further includes: Sending test data to the corresponding subsequent units through each preceding unit, wherein the preceding unit includes the communication unit and at least one of the acquisition units, and the subsequent unit includes at least one of the acquisition units; Dynamically adjusting the voltage-controlled crystal oscillator corresponding to each subsequent unit based on the number of clock edges of the received test data, so that the clock frequency and phase of the adjacent subsequent units are consistent with those of the previous units; Sending a delay measurement frame to the corresponding subsequent unit through each preceding unit, receiving feedback information returned by the corresponding subsequent unit in response to the delay measurement frame, and calculating the transmission delay between each preceding unit and the corresponding subsequent unit based on the feedback information; Starting from the communication unit, the whole network synchronization time frame is issued to each of the acquisition units step by step. Each of the whole network synchronization time frame includes the whole network synchronization timestamp of the previous unit and the transmission delay duration calculated by the previous unit. The whole network synchronization time frame is used to update the whole network synchronization timestamp of the receiving end. The error between the whole network synchronization timestamps updated by each of the acquisition units is less than the preset error threshold.

5. The method according to any one of claims 1 to 4, characterized in that The step of locating the partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal includes: Acquire a first starting timestamp of the first discharge pulse frame and a second starting timestamp of each of the second discharge pulse frames; Detecting a start time difference between the first start timestamp and each of the second start timestamps; When at least one of the start time differences is less than a corresponding preset time difference threshold, the partial discharge signal is located from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal, wherein the preset time difference threshold is determined based on a communication distance and a cable length corresponding to the start time difference.

6. The method according to any one of claims 1 to 4, characterized in that The step of locating the partial discharge signal from the second discharge pulse frame based on the characteristic information to obtain a second peak moment of the partial discharge signal includes: performing feature recognition on the second discharge pulse frame based on the feature information; When a target signal waveform having a similarity with the characteristic information higher than a preset similarity threshold is identified from the second discharge pulse frame, the peak moment of the target signal waveform is determined as the second peak moment of the partial discharge signal.

7. A partial discharge double-end positioning device, characterized in that: The device comprises: a receiving module, configured to receive a first discharge pulse frame sent by a first acquisition unit and a second discharge pulse frame sent by at least one second acquisition unit adjacent to the first acquisition unit, wherein the first discharge pulse frame includes a partial discharge signal having a signal amplitude exceeding a preset voltage threshold, and the second discharge pulse frame is generated by the second acquisition unit in response to a partial discharge locating event, wherein the partial discharge locating event is triggered by the first acquisition unit upon detecting the partial discharge signal; a first positioning module, configured to locate the partial discharge signal from the first discharge pulse frame to obtain a first peak moment of the partial discharge signal; a second positioning module, configured to extract characteristic information of the partial discharge signal from the first discharge pulse frame, and locate the partial discharge signal from the second discharge pulse frame based on the characteristic information to obtain a second peak moment of the partial discharge signal; A determination module is configured to determine a partial discharge position based on first cable positioning information corresponding to the first acquisition unit, second cable positioning information corresponding to the second acquisition unit, the first peak moment, and the second peak moment.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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