Partial discharge positioning and detecting system for super-large current wear-resistant liquid cooling cable

Abstract

This invention discloses a partial discharge location and detection system for ultra-high current wear-resistant liquid-cooled cables, belonging to the field of cable partial discharge detection technology. It forms a complete partial discharge location and detection solution for ultra-high current wear-resistant liquid-cooled cables through unit collaborative work, completely solving the core problem of difficult elimination of false discharge interference in traditional detection technologies. Through multi-parameter correlation analysis, it achieves accurate differentiation between false and real discharges, significantly reducing the false detection rate and providing a reliable basis for subsequent maintenance work. Simultaneously, it achieves focused and efficient partial discharge detection by dividing high / low probability partial discharge points, focusing on high-incidence areas to reduce detection intensity, avoiding the inefficiency of indiscriminate detection across the entire line, and improving the efficiency and accuracy of partial discharge location.

Description

Technical Field

[0001] This invention relates to the field of partial discharge detection technology for cables, specifically a partial discharge location and detection system for ultra-high current wear-resistant liquid-cooled cables. Background Technology

[0002] Against the backdrop of the power system's development towards ultra-high current and high power density, liquid-cooled cables, due to their excellent heat dissipation performance, have been widely used in key fields such as energy storage power stations, chemical power distribution, and new energy. In particular, ultra-high current wear-resistant liquid-cooled cables, with their characteristics of resistance to mechanical wear and adaptability to complex working conditions, have become core equipment for ensuring stable power transmission in high-load scenarios. Partial discharge is a core early signal reflecting the deterioration of cable insulation. If it is not detected and treated in a timely and accurate manner, it will gradually lead to insulation carbonization, breakdown and short circuit, and even cause serious safety accidents such as fires and large-scale power outages.

[0003] However, partial discharge detection of ultra-high current wear-resistant liquid-cooled cables still faces many industry technical bottlenecks:

[0004] On the one hand, in forced circulation liquid cooling systems, the operation of the pump causes periodic pressure pulsations in the coolant. Microbubbles or cavities generated by cable wear are prone to "air gap discharge" under pressure changes, producing acoustic and high-frequency current signals similar to real partial discharge signals, which are difficult to distinguish effectively by traditional detection techniques. For example, in the liquid-cooled cable system of a large energy storage power station, the coolant circulation pump operates continuously for a long time, and the frequency and amplitude of pressure pulsations are easily affected by pump speed fluctuations and changes in pipeline resistance, resulting in irregular pressure pulsation waveforms. Traditional fixed threshold judgment methods are difficult to accurately extract pressure signal characteristic parameters.

[0005] Meanwhile, liquid-cooled cables have complex installation structures and are affected by factors such as load fluctuations and temperature changes during operation. The partial discharge points are scattered, and traditional detection technologies require indiscriminate detection of the entire line, which is intensive, inefficient, and difficult to focus on areas with high partial discharge incidence, resulting in delayed location and untimely maintenance.

[0006] On the other hand, focusing only on the detection and location of partial discharge signals without establishing the correlation between partial discharge and cable wear makes it impossible to accurately determine the stage of partial discharge development. For example, in the long-term operation scenario of ultra-high current liquid-cooled cables, the location of cable wear and the location of partial discharge are not completely synchronized. The location method that only targets the location of a single partial discharge does not consider the impact of coolant flow on wear and partial discharge propagation.

[0007] To address the aforementioned technical deficiencies, a partial discharge location and detection system is proposed that can effectively eliminate false discharge interference, accurately locate partial discharge areas, and enable scientific maintenance, thereby meeting the actual needs of safe operation of ultra-high current wear-resistant liquid-cooled cables. Summary of the Invention

[0008] The purpose of this invention is to solve the problems mentioned above by proposing a partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables.

[0009] The objective of this invention can be achieved through the following technical solution: a partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables, comprising a location detection center, wherein the location detection center is connected to the following communication connections:

[0010] The false discharge interference elimination unit identifies false discharge interference in the cable and eliminates interference identification errors during cable operation.

[0011] The high-incidence area identification and detection unit identifies and detects high-incidence areas of liquid-cooled cables, and eliminates locations through high-incidence area identification and detection.

[0012] The surface discharge location unit locates partial discharge on the surface of the liquid-cooled cable and provides early warning based on the location results.

[0013] Furthermore, the process of the pseudo-discharge interference elimination unit is as follows:

[0014] Monitor the pressure pulsation waveform of the coolant; the partial discharge detection sensor synchronously collects signals and records the corresponding time points of the signals; according to the coolant supply period during cable operation, and the coolant supply amount, the corresponding pressure pulsation waveform is marked as an increasing pressure waveform according to the increasing supply amount; the corresponding pressure pulsation waveform is marked as a decreasing pressure waveform according to the decreasing supply amount.

[0015] Based on the distribution of time points within the supply period, the increasing voltage waveform and decreasing voltage waveform are connected, and the waveform changes corresponding to adjacent time points are constructed. If the waveform changes, the pressure signal at the current time point is recorded, and the main frequency and phase are extracted and marked as pressure signal characteristic parameters. The partial discharge detection signal at each time point within the supply period is obtained, and the main frequency and phase are extracted based on the partial discharge detection signal and marked as partial discharge signal characteristic parameters.

[0016] Furthermore, the supply period is eliminated by removing time points where no partial discharge detection signal is generated, and the remaining time points are marked as interference analysis periods;

[0017] The fluctuation trends of pressure signal characteristic parameters and partial discharge signal characteristic parameters during the interference analysis period are obtained and the corresponding time points are recorded. If the number of time points where the fluctuation trends of the two types of characteristic parameters are consistent exceeds the set overlap threshold, and the pulse frequency is continuously synchronized within the time period corresponding to the overlapping time points, the fluctuation process of pressure signal characteristic parameters and partial discharge signal characteristic parameters is marked as positively correlated, liquid pseudo-discharge signal is generated, and the corresponding time point is synchronously sent to the positioning detection center. After receiving the signal, the positioning detection center continuously collects data for the current supply period and does not perform operation and inspection on the cable parts corresponding to the collected signal characteristic parameters.

[0018] If the number of overlapping time points where the floating trends of the two types of characteristic parameters are consistent does not exceed the set overlap threshold, or if the pulse frequency interval period is not fixed within the time period corresponding to the overlapping time point, the floating process of the pressure signal characteristic parameter and the partial discharge signal characteristic parameter will be marked as negatively correlated, an insulation discharge signal will be generated, and the corresponding time point will be synchronously sent to the positioning and detection center.

[0019] Furthermore, the process of identifying and detecting units in high-incidence areas is as follows:

[0020] Based on the installation structure of the liquid-cooled cable, the liquid-cooled cable is divided into several partial discharge prediction points; partial discharge prediction point identification and detection are performed during the operation of the liquid-cooled cable.

[0021] When load fluctuations cause temperature fluctuations during the operation of the liquid-cooled cable, the detected partial discharge intensity at the corresponding partial discharge prediction point is obtained within the temperature fluctuation stage. Multiple temperature fluctuation stages are collected, and the intensity fluctuation trend is statistically analyzed based on the detected partial discharge intensity. If the detected partial discharge intensity fluctuation trend and the temperature fluctuation trend show a synchronous growth trend, or if the corresponding detected partial discharge intensity fluctuation span exceeds the set fluctuation span threshold, the corresponding partial discharge prediction point is marked as a high-probability partial discharge point. Conversely, if the detected partial discharge intensity fluctuation trend and the temperature fluctuation trend do not show a synchronous growth trend, and the corresponding detected partial discharge intensity fluctuation span does not exceed the set fluctuation span threshold, the corresponding partial discharge prediction point is marked as a low-probability partial discharge point.

[0022] Furthermore, partial discharge detection is performed on the liquid-cooled cable based on its load intensity. If, during the cyclical increase phase of the liquid-cooled cable's load intensity, the predicted partial discharge point overlaps with the phase of increasing load intensity, and the predicted partial discharge point is a high-probability partial discharge point, a high-probability partial discharge warning signal is immediately generated and simultaneously sent to the location detection center. If the predicted partial discharge point is a low-probability partial discharge point, the frequency of overlapping time points is statistically analyzed, and when the continuous statistical quantity reaches a set frequency threshold, a continuous partial discharge warning signal is generated and simultaneously sent to the location detection center.

[0023] Furthermore, after receiving the high-probability partial discharge warning signal, the positioning and detection center locates the high-probability partial discharge points and performs synchronous detection and maintenance on adjacent locations; after receiving the continuous partial discharge warning signal, the positioning and detection center locates and maintains the low-probability partial discharge points and re-evaluates the point type; when the continuous statistical quantity does not reach the set frequency threshold, the frequency is accumulated and statistically analyzed, and when the set cumulative frequency threshold is reached, an warning is issued.

[0024] Furthermore, the process of the surface discharge positioning unit is as follows:

[0025] The corresponding cable parts are determined based on the liquid pseudo-discharge signal and marked as liquid cooling wear locations; the corresponding cable parts are determined based on the insulation discharge signal and marked as partial discharge generation locations; the cable wear trajectory is constructed based on the coolant supply trajectory and the real-time identified liquid cooling wear locations; and the partial discharge propagation trajectory is constructed based on the distribution of partial discharge generation locations.

[0026] The percentage of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory is obtained. At the same time, the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value is obtained based on the partial discharge propagation trajectory.

[0027] Furthermore, if the proportion of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory exceeds the proportion threshold, or if the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value in the partial discharge propagation trajectory exceeds the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge influence stage; if the proportion of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory does not exceed the proportion threshold, and the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value in the partial discharge propagation trajectory does not exceed the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge stable stage.

[0028] Furthermore, during the partial discharge impact phase, the cable wear trajectory and partial discharge propagation trajectory are merged, and the merged trajectory is marked as the partial discharge continuous trajectory. Based on the partial discharge quantity of each cable part within the partial discharge continuous trajectory and the fluctuation process of the partial discharge quantity during the phase, including parameters such as the time of fluctuation and the amount of fluctuation, the source of partial discharge is traced according to the fluctuation process of the partial discharge quantity to eliminate the risk of partial discharge from the source. At the same time, the degree of partial discharge is classified according to the partial discharge quantity for targeted maintenance.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] 1. Pseudo-discharge interference elimination unit: By combining the stages of coolant supply change, the pressure pulsation waveform type is divided, waveform change characteristics are constructed, and core parameters such as main frequency and phase are extracted. At the same time, invalid periods without partial discharge signals are eliminated, which greatly improves the efficiency and accuracy of signal analysis.

[0031] Furthermore, by analyzing the correlation between the fluctuation trends of pressure signal characteristic parameters and partial discharge signal characteristic parameters, and combining the dual judgment criteria of the number of overlapping time points and pulse frequency synchronization, it can accurately distinguish between false discharge and real insulation discharge, effectively eliminating interference and misjudgment problems caused by coolant microbubbles, pressure pulsation, etc., avoiding ineffective maintenance and resource waste caused by false discharge misjudgment, and preventing the omission of real insulation discharge hidden dangers.

[0032] 2. High-incidence area identification and detection unit: Based on the installation and structural characteristics of liquid-cooled cables, the partial discharge prediction points are scientifically divided to avoid the redundancy of points and insufficient coverage of key areas caused by traditional indiscriminate detection. By analyzing the correlation trend between temperature fluctuation and partial discharge intensity, and the range of partial discharge intensity fluctuation, high / low probability partial discharge points are accurately divided, realizing the focusing of partial discharge detection, greatly reducing the intensity of location detection, and improving detection efficiency.

[0033] Furthermore, based on the load intensity variation pattern of liquid-cooled cables, a differentiated early warning mechanism is set up for high / low probability partial discharge points. High probability points will be warned immediately when the load increase and the partial discharge intensity increase overlap, while low probability points will be warned cumulatively based on the frequency of overlap. This ensures timely response to potential hazards in high-probability areas and avoids excessive warnings and ineffective maintenance in low-probability areas, thereby improving the scientific and rational nature of the early warning.

[0034] Meanwhile, by reducing the number of invalid detections at the same batch of abnormal points, the intensity of point location maintenance is alleviated, and blind maintenance before the warning level is reached is avoided. This effectively improves the accuracy and reliability of partial discharge detection, laying the foundation for efficient maintenance in the future.

[0035] 3. Surface discharge positioning unit: accurately marks the location of liquid-cooled wear and the location of partial discharge generation, constructs the cable wear trajectory through the coolant supply trajectory, and constructs the partial discharge propagation trajectory by combining the distribution of partial discharge generation locations, realizing the correlation analysis between wear and partial discharge, filling the gap of traditional technology that only focuses on the single partial discharge positioning;

[0036] Furthermore, by analyzing the percentage of wear locations that transition to partial discharge locations and the increase in the number of partial discharges exceeding the red line value, the system scientifically determines the partial discharge operation stage (impact stage / stable stage) of the cable, providing a precise basis for formulating maintenance strategies. During the partial discharge impact stage, a continuous partial discharge trajectory is constructed by merging trajectories, and the source is traced in conjunction with the fluctuation process of partial discharge, thereby eliminating the risk of partial discharge from the source. At the same time, targeted maintenance is carried out according to the degree of partial discharge, which reduces maintenance costs and prevents the further spread of potential partial discharge hazards. Attached Figure Description

[0037] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0038] Figure 1This is a system principle block diagram of the present invention;

[0039] Figure 2 This is a flowchart of the high-incidence area identification and detection unit method in this invention. Detailed Implementation

[0040] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0042] Please see Figure 1 As shown, the partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables includes a location detection center, which is connected to a pseudo-discharge interference elimination unit, a high-incidence area identification and detection unit, and a surface discharge location unit.

[0043] In a forced circulation liquid-cooled cable system, the coolant experiences periodic pressure pulsations (caused by the pump), and the cable may contain microbubbles or cavities caused by wear; the positioning detection center generates a false discharge interference elimination signal and sends it to the false discharge interference elimination unit.

[0044] After receiving the false discharge interference elimination signal, the false discharge interference elimination unit identifies the cable for false discharge interference and performs interference identification and error elimination during the cable operation period to improve the accuracy of identification. Microbubbles in the coolant may cause "air gap discharge" or generate similar acoustic or high-frequency current signals under pressure changes. However, these are systematic and periodic "false discharges" and have different physical meanings from the discharges caused by cable insulation defects, which can easily lead to misjudgment.

[0045] High-frequency pressure sensors are installed at the pump outlet and return port of the liquid cooling main pipeline to monitor the pressure pulsation waveform of the coolant; a partial discharge detection sensor synchronously acquires the signal and records the corresponding time point of the signal.

[0046] Based on the coolant supply period during cable operation and the coolant supply volume, the pressure pulsation waveform corresponding to the increasing supply volume is marked as an increasing pressure waveform; the pressure pulsation waveform corresponding to the decreasing supply volume is marked as a decreasing pressure waveform.

[0047] Based on the distribution of time points within the supply period, the increasing voltage waveform and decreasing voltage waveform are connected, and the waveform changes corresponding to adjacent time points are constructed. If the waveform changes, the pressure signal at the current time point is recorded, and the main frequency and phase are extracted and marked as pressure signal characteristic parameters. The partial discharge detection signal at each time point within the supply period is obtained, and the main frequency and phase are extracted based on the partial discharge detection signal and marked as partial discharge signal characteristic parameters.

[0048] The supply period is eliminated, and the time points where no partial discharge detection signal is generated are eliminated. The retained time points are marked as interference analysis periods.

[0049] The fluctuation trends of pressure signal characteristic parameters and partial discharge signal characteristic parameters during the interference analysis period are obtained and the corresponding time points are recorded. If the number of time points where the fluctuation trends of the two types of characteristic parameters are consistent exceeds the set overlap threshold, and the pulse frequency is continuously synchronized within the time period corresponding to the overlapping time points, the fluctuation process of pressure signal characteristic parameters and partial discharge signal characteristic parameters is marked as positively correlated, liquid pseudo-discharge signal is generated, and the corresponding time point is synchronously sent to the positioning detection center. After receiving the signal, the positioning detection center continuously collects data for the current supply period and does not perform operation and inspection on the cable parts corresponding to the collected signal characteristic parameters.

[0050] If the number of overlapping time points where the fluctuation trends of the two types of characteristic parameters are consistent does not exceed the set overlap threshold, or if the pulse frequency interval period within the time period corresponding to the overlapping time point is not fixed, the fluctuation process of the pressure signal characteristic parameter and the partial discharge signal characteristic parameter will be marked as negatively correlated, generating an insulation discharge signal and sending the corresponding time point synchronously to the positioning and detection center. After receiving the insulation discharge signal, the positioning and detection center will extract the cable part corresponding to the partial discharge detection signal and the partial discharge signal characteristic parameters, carry out maintenance on the corresponding cable part, extract the historical operation log of the current cable part, perform source tracing analysis, identify the cause, and carry out partial discharge interference control while maintaining the cable part.

[0051] After eliminating false discharge interference, the positioning and detection center generates a high-incidence area identification and detection signal and sends the high-incidence area identification and detection signal to the high-incidence area identification and detection unit.

[0052] Please see Figure 2As shown, after receiving the high-incidence area identification and detection signal, the high-incidence area identification and detection unit performs high-incidence area identification and detection on the liquid-cooled cable. The high-incidence area identification and detection is used to exclude points, so as to reduce the intensity of location detection and improve the location accuracy during partial discharge detection.

[0053] Based on the installation structure of the liquid-cooled cable, the liquid-cooled cable is divided into several partial discharge prediction points; partial discharge prediction point identification and detection are performed during the operation of the liquid-cooled cable.

[0054] When load fluctuations cause temperature fluctuations during the operation of liquid-cooled cables, the detected partial discharge intensity at the corresponding partial discharge prediction point is obtained during the temperature fluctuation phase. Multiple temperature fluctuation phases are collected, and the intensity fluctuation trend is statistically analyzed based on the detected partial discharge intensity.

[0055] If the fluctuation trend of the detected partial discharge intensity and the temperature fluctuation trend show a synchronous growth trend, or if the corresponding fluctuation range of the detected partial discharge intensity exceeds the set fluctuation range threshold, then the corresponding partial discharge prediction point will be marked as a high-probability partial discharge point; conversely, if the fluctuation trend of the detected partial discharge intensity and the temperature fluctuation trend do not show a synchronous growth trend, and the corresponding fluctuation range of the detected partial discharge intensity does not exceed the set fluctuation range threshold, then the corresponding partial discharge prediction point will be marked as a low-probability partial discharge point.

[0056] Partial discharge testing of liquid-cooled cables is performed based on their load strength.

[0057] If, during the cyclical increase phase of the load intensity of the liquid-cooled cable, the partial discharge prediction point overlaps with the phase of load intensity increase, and the predicted point is a high-probability partial discharge point, a high-probability partial discharge warning signal is immediately generated and simultaneously sent to the location detection center. Upon receiving the signal, the location detection center locates the high-probability partial discharge point and performs synchronous detection and maintenance on adjacent points. If the predicted point is a low-probability partial discharge point, the frequency of overlapping time points is statistically analyzed. When the continuous statistical count reaches a set frequency threshold, a continuous partial discharge warning signal is generated and simultaneously sent to the location detection center. Upon receiving the signal, the location detection center locates and maintains the low-probability partial discharge point and reassesses the point type. If the continuous statistical count does not reach the set frequency threshold, frequency accumulation statistics are performed. When the accumulated frequency threshold is reached, a warning is issued.

[0058] Completing the identification and detection of high-incidence areas can effectively reduce the number of abnormal points in the same batch. When the number of partial discharge points increases, it can effectively alleviate the intensity of point location maintenance and avoid maintenance before the partial discharge warning level is reached, which would reduce the accuracy of partial discharge detection.

[0059] Subsequently, the positioning and detection center generates a surface discharge positioning signal and sends it to the surface discharge positioning unit;

[0060] After receiving the surface discharge location signal, the surface discharge location unit performs partial discharge location on the surface of the liquid-cooled cable and performs detection and early warning based on the partial discharge location results;

[0061] The corresponding cable section is determined based on the liquid pseudo-discharge signal and marked as the liquid-cooled wear location; the corresponding cable section is determined based on the insulation discharge signal and marked as the partial discharge generation location.

[0062] Based on the coolant supply trajectory and the real-time identified liquid cooling wear locations, a cable wear trajectory is constructed; and based on the distribution of partial discharge generation locations, a partial discharge propagation trajectory is constructed.

[0063] The percentage of liquid-cooled wear locations that are synchronously converted into partial discharge generation locations in the cable wear trajectory is obtained. At the same time, the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value is obtained based on the partial discharge propagation trajectory.

[0064] If the percentage of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory exceeds the percentage threshold, or if the increase in the number of partial discharge generation locations with partial discharge exceeding the red line value in the partial discharge propagation trajectory exceeds the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge influence stage; if the percentage of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory does not exceed the percentage threshold, and the increase in the number of partial discharge generation locations with partial discharge exceeding the red line value in the partial discharge propagation trajectory does not exceed the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge stable stage.

[0065] During the partial discharge impact phase, the cable wear trajectory and partial discharge propagation trajectory are merged, and the merged trajectory is marked as the partial discharge continuous trajectory. Based on the partial discharge quantity of each cable part within the partial discharge continuous trajectory and the fluctuation process of the partial discharge quantity during the phase, including parameters such as the time of fluctuation and the amount of fluctuation, the source of partial discharge is traced according to the fluctuation process of the partial discharge quantity to eliminate the risk of partial discharge from the source. At the same time, the degree of partial discharge is classified according to the partial discharge quantity for targeted maintenance.

[0066] This invention achieves accurate identification, efficient location, and scientific repair of partial discharges by constructing a collaborative working system consisting of a positioning and detection center, a pseudo-discharge interference elimination unit, a high-incidence area identification and detection unit, and a surface discharge positioning unit.

[0067] Thresholds, preset values, preset ranges, etc. are set for result comparison and analysis to determine whether they are good or bad. The value of these thresholds is determined by a combination of large-scale model analysis of sample data and human experience. They can also be adjusted appropriately based on seasonal or common-sense influences.

[0068] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables, characterized in that, This includes a positioning detection center, whose communication connections include: The false discharge interference elimination unit identifies false discharge interference in the cable and eliminates interference identification errors during cable operation. The high-incidence area identification and detection unit identifies and detects high-incidence areas of liquid-cooled cables, and eliminates locations through high-incidence area identification and detection. The surface discharge location unit locates partial discharge on the surface of the liquid-cooled cable and provides early warning based on the location results.

2. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 1, characterized in that, The process of the pseudo-discharge interference elimination unit is as follows: Monitor the pressure pulsation waveform of the coolant; the partial discharge detection sensor synchronously collects the signal and records the corresponding time point of the signal; according to the coolant supply period during cable operation, and the coolant supply amount, the corresponding pressure pulsation waveform is marked as an incremental pressure waveform according to the stage of increasing supply amount; The pressure pulsation waveform corresponding to the phase of supply decline is marked as a decreasing pressure waveform. Based on the distribution of time points within the supply period, the increasing pressure waveform and the decreasing pressure waveform are connected, and the waveform changes corresponding to adjacent time points are constructed. If the waveform changes, the pressure signal at the current time point is recorded, and the main frequency and phase are extracted and marked as pressure signal characteristic parameters. Acquire partial discharge detection signals at various time points during the supply period, and extract the main frequency and phase based on the partial discharge detection signals, marking them as characteristic parameters of the partial discharge signal.

3. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 2, characterized in that, The supply period is eliminated, and the time points where no partial discharge detection signal is generated are eliminated. The retained time points are marked as interference analysis periods. The fluctuation trends of pressure signal characteristic parameters and partial discharge signal characteristic parameters during the interference analysis period are obtained and the corresponding time points are recorded. If the number of time points where the fluctuation trends of the two types of characteristic parameters are consistent exceeds the set overlap threshold, and the pulse frequency is continuously synchronized within the time period corresponding to the overlapping time points, the fluctuation process of pressure signal characteristic parameters and partial discharge signal characteristic parameters is marked as positively correlated, liquid pseudo-discharge signal is generated, and the corresponding time point is synchronously sent to the positioning detection center. After receiving the signal, the positioning detection center continuously collects data for the current supply period and does not perform operation and inspection on the cable parts corresponding to the collected signal characteristic parameters. If the number of overlapping time points where the floating trends of the two types of characteristic parameters are consistent does not exceed the set overlap threshold, or if the pulse frequency interval period is not fixed within the time period corresponding to the overlapping time point, the floating process of the pressure signal characteristic parameter and the partial discharge signal characteristic parameter will be marked as negatively correlated, an insulation discharge signal will be generated, and the corresponding time point will be synchronously sent to the positioning and detection center.

4. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 1, characterized in that, The process of identifying and detecting high-incidence areas is as follows: Based on the installation structure of the liquid-cooled cable, the liquid-cooled cable is divided into several partial discharge prediction points; partial discharge prediction point identification and detection are performed during the operation of the liquid-cooled cable. When load fluctuations cause temperature fluctuations during the operation of the liquid-cooled cable, the detected partial discharge intensity at the corresponding partial discharge prediction point is obtained within the temperature fluctuation stage. Multiple temperature fluctuation stages are collected, and the intensity fluctuation trend is statistically analyzed based on the detected partial discharge intensity. If the detected partial discharge intensity fluctuation trend and the temperature fluctuation trend show a synchronous growth trend, or if the corresponding detected partial discharge intensity fluctuation span exceeds the set fluctuation span threshold, the corresponding partial discharge prediction point is marked as a high-probability partial discharge point. Conversely, if the detected partial discharge intensity fluctuation trend and the temperature fluctuation trend do not show a synchronous growth trend, and the corresponding detected partial discharge intensity fluctuation span does not exceed the set fluctuation span threshold, the corresponding partial discharge prediction point is marked as a low-probability partial discharge point.

5. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 4, characterized in that, Partial discharge (PD) detection is performed on the liquid-cooled cable based on its load intensity. If, during the cyclical increase phase of the load intensity of the liquid-cooled cable, the PD prediction point overlaps with the cyclical increase phase of the load intensity, and the predicted PD point is a high-probability PD point, a high-probability PD warning signal is immediately generated and simultaneously sent to the location detection center. If the predicted PD point is a low-probability PD point, the frequency of overlapping time points is statistically analyzed, and when the continuous statistical quantity reaches a set frequency threshold, a continuous PD warning signal is generated and simultaneously sent to the location detection center.

6. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 5, characterized in that, After receiving a high-probability partial discharge (PD) warning signal, the positioning and detection center locates the high-probability PD locations and performs synchronous detection and maintenance on adjacent locations. After receiving a continuous PD warning signal, the positioning and detection center locates and maintains the low-probability PD locations and re-evaluates the location type. If the continuous statistical quantity does not reach the set frequency threshold, the frequency is accumulated and statistically analyzed. When the set cumulative frequency threshold is reached, an warning is issued.

7. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 1, characterized in that, The process of the surface discharge positioning unit is as follows: The corresponding cable parts are determined based on the liquid pseudo-discharge signal and marked as liquid cooling wear locations; the corresponding cable parts are determined based on the insulation discharge signal and marked as partial discharge generation locations; the cable wear trajectory is constructed based on the coolant supply trajectory and the real-time identified liquid cooling wear locations; and the partial discharge propagation trajectory is constructed based on the distribution of partial discharge generation locations. The percentage of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory is obtained. At the same time, the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value is obtained based on the partial discharge propagation trajectory.

8. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 7, characterized in that, If the proportion of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory exceeds the proportion threshold, or if the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value in the partial discharge propagation trajectory exceeds the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge influence stage. If the proportion of liquid-cooled wear locations that synchronously transform into partial discharge generation locations in the cable wear trajectory does not exceed the proportion threshold, and the increase in the number of partial discharge generation locations whose partial discharge exceeds the red line value in the partial discharge propagation trajectory does not exceed the increase threshold, then it is inferred that the liquid-cooled cable is currently in the partial discharge stable stage.

9. The partial discharge location detection system for ultra-high current wear-resistant liquid-cooled cables according to claim 8, characterized in that, During the partial discharge impact phase, the cable wear trajectory and partial discharge propagation trajectory are merged, and the merged trajectory is marked as the partial discharge continuous trajectory. Based on the partial discharge quantity of each cable part within the partial discharge continuous trajectory and the fluctuation process of the partial discharge quantity within the phase, the source is traced according to the fluctuation process of the partial discharge quantity to eliminate the partial discharge risk from the source. At the same time, the degree of partial discharge is classified according to the partial discharge quantity for targeted maintenance.

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