A method, apparatus, medium, and device for detecting aging of a power cable

Abstract

This invention discloses an aging detection method, apparatus, medium, and equipment for power cables. The method includes: acquiring first aging data of the cable body and second aging data of intermediate cable joints; outputting additional aging increments of the intermediate cable joints at corresponding aging time nodes on different axial positions of the cable body through an aging effect transmission model; and fusing the first aging data and the additional aging increments to generate optimized aging test results. This invention superimposes the cable body's own aging data with the additional aging increments, which not only better reflects the actual operating conditions of the cable and significantly improves the accuracy of aging detection results, but also relies entirely on existing aging devices for cables or cable accessories, requiring no hardware modification. Furthermore, by introducing a hybrid model including heat conduction, electric field distortion, and time effects during the increment calculation process, stable modeling is achieved even under small sample conditions, providing a more reliable basis for cable life prediction.

Description

Technical Field

[0001] This invention relates to the field of cable testing, and more particularly to a method, apparatus, medium, and equipment for aging testing of power cables. Background Technology

[0002] Power cable systems typically consist of two main parts: the cable itself and cable accessories (such as joints and terminations). During long-term operation, due to the effects of current heating and environmental factors, the insulation materials of the cable and its accessories inevitably age, leading to a gradual decline in their mechanical and electrical properties. Aging performance testing accelerates this degradation process by simulating long-term high-temperature conditions, thereby predicting the cable's safety status after several years or even decades of use in a relatively short period.

[0003] Currently, the industry standard for simulating the aging performance of power cables involves placing cable samples or accessories in an aging device and simulating specific environmental factors such as temperature, humidity, and operating voltage to conduct accelerated aging tests on the cable body or accessories separately. This simulation typically treats the cable body as an isolated test object, neglecting the influence of physically connected and interacting cable accessories (especially joints) on the overall thermal aging process. In actual operating conditions, joints and the cable body together form a complete electrical path. The aging state of the joint not only alters the local electric field distortion distribution, but its own thermal resistance characteristics also lead to local temperature rise. Simultaneously, thermal expansion and contraction during operation create a breathing effect between the accessories and the cable insulation layer. This multi-physics coupling effect significantly accelerates the thermal aging process of the cable body, especially near the joint, thus affecting the accuracy of individual aging tests on existing cable samples. Summary of the Invention

[0004] This invention provides a method, apparatus, medium, and equipment for aging detection of power cables, which solves the technical problem of inaccurate aging detection results of power cables in the prior art.

[0005] A first aspect of this invention provides an aging detection method for power cables, comprising the following steps:

[0006] Step 1: Obtain the first aging data of the cable body and the second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include the aging parameters of the cable body and the aging parameters of the cable joint corresponding to different aging time nodes.

[0007] Step 2: Input the second aging data into the pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node.

[0008] Step 3: The first aging data and the additional aging increment at the corresponding aging time node are fused to generate optimized aging test results for different axial positions of the cable body.

[0009] A second aspect of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the aging detection method for power cables described above.

[0010] A third aspect of the present invention provides an aging detection device for power cables, including a computer-readable storage medium and a processor, wherein the processor executes a computer program on the computer-readable storage medium to implement the steps of the aging detection method for power cables described above.

[0011] A fourth aspect of this invention provides an aging detection device for power cables, comprising a first acquisition module, a second acquisition module, and a fusion module.

[0012] The first acquisition module is used to acquire first aging data of the cable body and second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include cable body aging parameters and cable joint aging parameters corresponding to different aging time nodes.

[0013] The second acquisition module is used to input the second aging data into a pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node.

[0014] The fusion module is used to fuse the first aging data and the additional aging increment at the corresponding aging time node to generate optimized aging test results for different axial positions of the cable body.

[0015] The beneficial effects of this invention are as follows: This invention provides an aging detection method, device, medium, and equipment for power cables. By superimposing the cable's own aging data with additional aging increments generated based on the aging state of intermediate joints, it better reflects the actual operating conditions of the cable and significantly improves the accuracy of aging detection results. At the same time, this method relies entirely on existing aging devices for cables or cable accessories without requiring hardware modifications. In the incremental calculation process, by introducing a hybrid model that includes heat conduction, electric field distortion, and time effects, the spatial quantification of the joint's influence along the axial direction is achieved. Stable modeling is still possible under small sample conditions, providing a more reliable basis for cable life prediction.

[0016] To make the above-mentioned objects, features and advantages of the invention more apparent and understandable, preferred embodiments of the invention are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating the aging test method for power cables provided in Example 1;

[0019] Figure 2 This is a schematic diagram of the aging detection device for power cables provided in Example 2;

[0020] Figure 3 This is a schematic diagram of the aging detection equipment for power cables provided in Example 3. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0022] It should be noted that, unless otherwise specified, the various features in the embodiments of this invention can be combined with each other, all of which are within the protection scope of this invention. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the device or the order in the flowchart. Moreover, the terms "first," "second," and "third" used in this invention do not limit the data or execution order, but only distinguish identical or similar items with essentially the same function and effect.

[0023] As those skilled in the art know, existing aging devices typically assess the aging status of intermediate cable joints and the cable body in isolation, and predict faults or lifespan. In practical applications, this approach can lead to situations where, during aging testing, the aging of the intermediate cable joint or the cable body itself has not yet reached the critical threshold. However, during use, the actual aging degree of the cable body, especially near the intermediate cable joint, differs significantly from the simulated aging process of the aging device. This is because axial heat conduction and electric field distortion effects cause accelerated insulation degradation in adjacent cable bodies on both sides, leading to the first reaching of the aging critical value. If only the operating conditions of the cable body itself are considered in a conventional aging assessment, the aging transmission effect induced by the intermediate joint will be completely ignored, resulting in the inability to provide timely and accurate early warnings of potential problems in the cable body.

[0024] Figure 1 This is a schematic flowchart of an aging detection method for power cables provided in Example 1. Figure 1 As shown, it includes the following steps:

[0025] Step 1: Obtain the first aging data of the cable body and the second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include the aging parameters of the cable body and the aging parameters of the cable joint corresponding to different aging time nodes.

[0026] Step 2: Input the second aging data into the pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node.

[0027] Step 3: The first aging data and the additional aging increment at the corresponding aging time node are fused to generate optimized aging test results for different axial positions of the cable body.

[0028] Traditional testing methods often only provide the average aging status of the entire cable. The above embodiment offers a method for aging testing of power cables. By establishing an aging effect transmission model, it quantifies the "additional aging increment" caused by intermediate cable joints on the cable body and integrates it with the basic aging data of the cable body. This enables differentiated assessment of the aging status at different axial positions of the cable, improving the accuracy of aging test results for the entire cable, especially for cable sections most severely affected by hotspot effects or electric field distortion caused by joint defects. Furthermore, this invention can utilize existing cable / cable accessory aging testing equipment and conventional electrical testing instruments, meaning it can be directly deployed in existing laboratories or maintenance systems without hardware modifications or upgrades. This significantly reduces the hardware costs for technology implementation, making it highly applicable and valuable for widespread adoption.

[0029] The following specific embodiments will be used to describe each step of the above method in detail.

[0030] As those skilled in the art know, in step 1, the first aging data of the cable body and the second aging data of the intermediate cable joint under preset aging conditions can be obtained by existing aging devices.

[0031] Specifically, an aging device typically includes an aging parameter adjustment module and a cable shape adjustment module. The cable shape adjustment module includes adjustment brackets, rollers, bending components, etc., to fix the cable under test (excluding cable accessories) in a manner simulating actual engineering laying conditions. For example, the bending components simulate the bending laying state of the cable in actual working conditions, or the height difference of the rollers simulates the straight laying state or the natural sag state of the cable in actual working conditions, ensuring the accuracy of the aging benchmark test results. During the aging test, the aging parameter adjustment module regulates temperature, humidity, voltage, etc. For example, it uses an oil bath heating system or heating wire in conjunction with a high-precision PID controller to achieve precise control of the ambient temperature inside the chamber, thereby executing the preset aging scheme and collecting corresponding aging data at multiple time points through testing instruments.

[0032] For example, the cable body aging parameters include at least one of the following: partial discharge, insulation resistance, dielectric loss factor, and tensile strength of the cable body; the cable joint aging parameters include at least one of the following: joint operating temperature, partial discharge, dielectric loss factor, and contact resistance of the intermediate cable joint; the additional aging increment establishes a coordinate mapping relationship along the cable axis to identify the acceleration of aging effects at different distances from the intermediate cable joint. Of course, in other embodiments, the cable body aging parameters and cable joint aging parameters may also include other mechanical or electrical indicators that can reflect the thermal aging process, such as the cable body's elongation at break, breakdown voltage, etc. The specific characterization meaning and acquisition methods of the above parameters, such as the type of detection device and data preprocessing methods, are described in detail in existing technical documents. Those skilled in the art can directly select or adapt them according to actual detection needs, and will not be elaborated further here.

[0033] For example, the preset aging conditions include cable operating parameters and an aging simulation scheme. The cable operating parameters include operating temperature, operating humidity, and / or operating voltage. The aging simulation scheme includes an automatic adjustment scheme for the cable operating parameters over time to accelerate or decelerate the aging process. In a preferred embodiment, multiple working scenarios can be preset, and initial cable operating parameters and time-varying curves of the cable operating parameters can be set for each working scenario. This allows for one-click selection of working scenarios and automatic adjustment of the aging process, improving operational convenience and detection efficiency.

[0034] In one specific embodiment, the aging effect transmission model is established as follows:

[0035] Step 201: Query historical cable maintenance data, collect the second historical aging data of the intermediate cable joint and the historical comprehensive aging data of the cable body of the two sides at multiple time points;

[0036] Step 202: Collect first aging data of the same cable body under the same working conditions and at the same time point using an aging device;

[0037] Step 203: Calculate the difference between the historical comprehensive aging data and the first aging data to form a training sample set with the second historical aging data as input and the difference as output, and use machine learning algorithms or regression analysis to fit the aging effect transmission model.

[0038] In one specific embodiment, the aging effect transmission model is established as follows: First, second historical aging data of intermediate cable joints at multiple different time points are extracted from historical cable maintenance records. This includes data such as joint operating temperature, partial discharge, dielectric loss factor, and contact resistance. Simultaneously, historical comprehensive aging data of multiple axial positions of the cable body within a predetermined length range on both sides of the joint at the corresponding time points is collected; this data already includes the influence of the intermediate joint. Then, an aging experiment is conducted on a pure cable body (without joints) of the same model under the same operating conditions and time points using an aging device to obtain the first aging data of the cable body, i.e., the basic aging data of its own aging unaffected by the intermediate cable joint. The difference between the aforementioned historical comprehensive aging data and the first aging data is used to obtain the actual additional aging increment caused by the joint. This difference is used as the output, and the second historical aging data is used as the input to construct a training sample set. Finally, machine learning algorithms, such as BP neural networks, support vector regression, or regression analysis, are used to train the training sample set to fit a mapping model from the joint aging state to the additional aging increment of the cable body. This method makes full use of on-site maintenance data and laboratory measured data (such as historical measured data), and separates the joint effect from the overall aging to build a separate model. The model output has a clear physical meaning, which is conducive to improving the prediction accuracy of additional aging increment in subsequent testing.

[0039] Preferably, in one specific embodiment, when the amount of data in the training sample set is lower than a preset threshold, a hybrid modeling method is adopted, specifically as follows:

[0040] A basic model of aging effects is established, including a defect type influence coefficient, a time influence factor, and a comprehensive adjustment coefficient. The defect type influence coefficient is used to quantify the degree of differentiated influence of different joint defect types on the electric field distortion of the cable body. The time influence factor is used to characterize the aging effect rate of the middle cable joint on the cable bodies on both sides as the aging time increases. The comprehensive adjustment coefficient is used to characterize the comprehensive correction effect of factors other than electric field distortion and increased local thermal resistance on aging transmission.

[0041] Using the training sample set, with the goal of minimizing the mean square error between the predicted additional aging increment and the measured additional aging increment, the parameters of the basic model of the aging effect are trained using the nonlinear least squares method to generate the aging effect transmission model.

[0042] The hybrid modeling method described above can effectively construct an aging effect transmission model even with a limited amount of training sample data. This method first decomposes the aging transmission law of intermediate cable joints to the cable body into three physically meaningful factors: defect type influence coefficient, time influence factor, and comprehensive adjustment coefficient. The defect type influence coefficient addresses the differentiated impact of different joint defects (such as water trees, air gaps, and scratches) on electric field distortion. The time influence factor reflects the accelerating effect of aging rate with increasing operating time. The comprehensive adjustment coefficient flexibly characterizes the combined influence of factors other than electric field distortion and increased local thermal resistance, such as environmental humidity, batch material differences, and joint connection structure. This approach requires only a small amount of additional aging increment data constructed from historical samples. With the goal of minimizing the mean square error between predicted and measured values, the coefficients can be efficiently identified and optimized using a nonlinear least squares method. Compared to purely data-driven models, this hybrid modeling method reduces the dependence on the number of training samples, effectively avoiding overfitting under small sample conditions and ensuring that the model maintains high robustness and generalization ability even with limited samples.

[0043] For example, in a preferred embodiment, the basic model of aging effects can be characterized as follows:

[0044] ,

[0045] In the above formula, Represents spatial location, specifically the axial distance from a point on the cable body to the center of the intermediate cable joint; t represents aging time. , where n is the base time and n is the time influence factor, used to characterize the rate of change of aging effects over time; These are fixed weighting coefficients set based on empirical values. The length of the thermal effect characteristic. The characteristic length is the influence of electric field distortion, and K is the comprehensive adjustment coefficient. The aging factor of the intermediate cable joint is obtained by comprehensively considering the second aging data of the intermediate cable joint and the defect type influence factor δ, wherein the parameter is... The training sample set was optimized and fitted to obtain the desired result. It can be preset as an empirical constant, where δ is the influence coefficient corresponding to different defect types set based on empirical values.

[0046] For example, in one specific embodiment, step 3 fuses the first aging data and the additional aging increment at the corresponding aging time node, specifically as follows:

[0047] Including 301, the discrete additional aging increment output by the aging effect transmission model is spatially interpolated, and a continuously distributed aging increment function is established based on the interpolation result. The input of the aging increment function is the axial position of the cable, and the output is the corresponding additional aging increment.

[0048] Step 302: Obtain the target additional aging increment at the target location using the aging increment function, and superimpose it with the first aging data at the target location to generate optimized aging test results for different axial positions. The above fusion step converts the discrete additional aging increment output by the aging influence transmission model into a continuously distributed aging increment function through spatial interpolation, ensuring accurate acquisition of the additional aging influence of the joint at any axial position, effectively overcoming the problem of insufficient data volume caused by limited sampling points. Based on this, the additional aging increment at the target location is superimposed point-by-point with the first aging data at the corresponding location (in a preferred embodiment, first aging data from multiple axial positions can be collected) to generate optimized aging test results along the cable axis. This processing method not only retains the aging information of the cable itself in the original test data but also incorporates the differentiated influence of intermediate cable joints on the cable at different distances, intuitively presenting the aging degree variation curve with axial distance and the boundary of high-risk sections, providing more comprehensive data support for subsequent remaining life segment prediction, fault location early warning, and precise maintenance.

[0049] In one specific embodiment, if the target additional aging increment at the target location is inconsistent with the feature attributes of the first aging data, a pre-established mapping model is invoked to perform feature value transformation, and the transformation result is used to perform data fusion to generate optimized aging test results, thereby avoiding erroneous evaluation results caused by feature inconsistency.

[0050] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0051] This invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the aging detection method for power cables described above.

[0052] Figure 2 This is a schematic diagram of the aging detection device for power cables provided in Example 2, as shown below. Figure 2 As shown, it includes a first acquisition module 100, a second acquisition module 200, and a fusion module 300.

[0053] The first acquisition module 100 is used to acquire first aging data of the cable body and second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include cable body aging parameters and cable joint aging parameters corresponding to different aging time nodes.

[0054] The second acquisition module 200 is used to input the second aging data into a pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node.

[0055] The fusion module 300 is used to fuse the first aging data and the additional aging increment at the corresponding aging time node to generate optimized aging test results for different axial positions of the cable body.

[0056] The above embodiments provide an aging detection device for power cables. By establishing an aging effect transmission model, the "additional aging increment" generated by intermediate cable joints on the cable body is quantified and integrated with the basic aging data of the cable body. This enables differentiated assessment of the aging state at different axial positions of the cable, improving the accuracy of aging test results for the entire cable, especially for cable sections most severely affected by hotspot effects or electric field distortion caused by joint defects. Furthermore, this invention can utilize existing cable / cable accessory aging testing devices and conventional electrical testing instruments, meaning it can be directly deployed in existing laboratories or maintenance systems without hardware modifications or upgrades, significantly reducing the hardware cost of technology implementation and possessing strong applicability and promotional value.

[0057] In a preferred embodiment, the system further includes a model building module, which specifically includes:

[0058] The first data acquisition unit is used to query historical cable maintenance data, collect the second historical aging data of the intermediate cable joint at multiple time points, and the historical comprehensive aging data of the cable body at preset lengths on both sides.

[0059] The second data acquisition unit is used to collect the first aging data of the same cable body under the same working conditions and the same time node through the aging device.

[0060] The training unit is used to calculate the difference between the historical comprehensive aging data and the first aging data, form a training sample set with the second historical aging data as input and the difference as output, and fit the aging effect transmission model using machine learning algorithms or regression analysis.

[0061] In a preferred embodiment, the training unit specifically includes:

[0062] The model building unit is used to establish a basic model of aging effects, including defect type influence coefficient, time influence factor, and comprehensive adjustment coefficient. The defect type influence coefficient is used to quantify the degree of differentiated influence of different joint defect types on the electric field distortion of the cable body. The time influence factor is used to characterize the aging influence rate of the middle cable joint on the cable bodies on both sides as the aging time increases. The comprehensive adjustment coefficient is used to characterize the comprehensive correction effect of factors other than electric field distortion and local thermal resistance on aging transmission.

[0063] The parameter optimization unit is used to train the parameters of the aging effect basic model using the training sample set with the goal of minimizing the mean square error between the predicted additional aging increment and the measured additional aging increment, and to generate the aging effect transmission model.

[0064] In a preferred embodiment, the fusion module 300 specifically includes:

[0065] The interpolation unit is used to perform spatial interpolation on the discrete additional aging increment output by the aging effect transmission model, and to establish a continuously distributed aging increment function based on the interpolation result. The input of the aging increment function is the axial position of the cable, and the output is the corresponding additional aging increment.

[0066] The fusion unit obtains the target additional aging increment at the target location through the aging increment function, and superimposes it with the first aging data at the target location to generate optimized aging test results for different axial positions.

[0067] In a preferred embodiment, the fusion module 300 further includes an alignment unit, which is used to call a pre-established mapping model to perform feature value conversion when the target additional aging increment at the target location is inconsistent with the feature attributes of the first aging data, and to perform data fusion through the conversion result to generate optimized aging test results.

[0068] It should be noted that the explanation of the above-described embodiments of the aging test method for power cables also applies to the aging test device for power cables described above, and will not be repeated here.

[0069] This invention also provides an aging detection device for power cables, including a computer-readable storage medium and a processor. When the processor executes a computer program on the computer-readable storage medium, it implements the steps of the aging detection method for power cables described above.

[0070] Figure 3 This is a schematic diagram of the aging detection equipment for power cables provided in Embodiment 3 of the present invention, as shown below. Figure 3 As shown, the aging detection device 8 for power cables in this embodiment includes: a processor 80, a readable storage medium 81, and a computer program 82 stored in the readable storage medium 81 and executable on the processor 80. When the processor 80 executes the computer program 82, it implements the steps in the various method embodiments described above, for example... Figure 1 The steps shown. Alternatively, when the processor 80 executes the computer program 82, it implements the functions of each module in the above-described device embodiments, for example... Figure 2 The functions of the module shown.

[0071] For example, the computer program 82 may be divided into one or more modules, which are stored in the readable storage medium 81 and executed by the processor 80 to complete the present invention. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program 82 in the aging detection device 8 for power cables.

[0072] The aging detection device 8 for the power cable may include, but is not limited to, a processor 80 and a readable storage medium 81. Those skilled in the art will understand that... Figure 3 This is merely an example of the aging detection device 8 for power cables and does not constitute a limitation on the aging detection device 8 for power cables. It may include more or fewer components than shown, or combine certain components, or different components. For example, the aging detection device for power cables may also include a power management module, a computing processing module, input / output devices, network access devices, buses, etc.

[0073] The processor 80 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0074] The readable storage medium 81 can be an internal storage unit of the power cable aging detection device 8, such as a hard drive or memory of the power cable aging detection device 8. The readable storage medium 81 can also be an external storage device of the power cable aging detection device 8, such as a plug-in hard drive, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the power cable aging detection device 8. Further, the readable storage medium 81 can include both internal storage units and external storage devices of the power cable aging detection device 8. The readable storage medium 81 is used to store the computer program and other programs and data required by the power cable aging detection device. The readable storage medium 81 can also be used to temporarily store data that has been output or will be output.

[0075] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0076] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0077] Those skilled in the art will recognize that the units and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0078] In the embodiments provided by this invention, it should be understood that the disclosed apparatus / terminal devices and methods can be implemented in other ways. For example, the apparatus / terminal device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0079] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0080] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0081] The present invention is not limited to the description in the specification and embodiments, and thus other advantages and modifications can be readily realized by those skilled in the art. Therefore, the present invention is not limited to the specific details, representative devices and illustrated examples shown and described herein without departing from the spirit and scope of the general concept as defined by the claims and their equivalents.

Claims

1. A method for aging detection of power cables, characterized in that, Includes the following steps: Step 1: Obtain the first aging data of the cable body and the second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include the aging parameters of the cable body and the aging parameters of the cable joint corresponding to different aging time nodes. Step 2: Input the second aging data into the pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node. Step 3: The first aging data and the additional aging increment at the corresponding aging time node are fused to generate optimized aging test results for different axial positions of the cable body.

2. The aging detection method for power cables according to claim 1, characterized in that, The cable body aging parameters include at least one of the following: partial discharge quantity, insulation resistance, dielectric loss factor, and tensile strength of the cable body. The aging parameters of the cable joint include at least one of the following: joint operating temperature, partial discharge, dielectric loss factor, and contact resistance of the intermediate cable joint. The additional aging increment establishes a coordinate mapping relationship along the cable axis to identify the acceleration of aging effects at different distances from the intermediate cable joint.

3. The aging detection method for power cables according to claim 1, characterized in that, The preset aging conditions include cable operating parameters and an aging simulation scheme. The cable operating parameters include operating temperature, operating humidity and / or operating voltage. The aging simulation scheme includes an automatic adjustment scheme for the cable operating parameters over time to accelerate or decelerate the aging process.

4. The aging test method for power cables according to any one of claims 1-3, characterized in that, The specific steps for establishing a model for the transmission of aging effects are as follows: Step 201: Query historical cable maintenance data, collect the second historical aging data of the intermediate cable joint and the historical comprehensive aging data of the cable body of the two sides at multiple time points; Step 202: Collect first aging data of the same cable body under the same working conditions and at the same time point using an aging device; Step 203: Calculate the difference between the historical comprehensive aging data and the first aging data to form a training sample set with the second historical aging data as input and the difference as output, and use machine learning algorithms or regression analysis to fit the aging effect transmission model.

5. The aging detection method for power cables according to claim 4, characterized in that, When the amount of data in the training sample set is lower than a preset threshold, a hybrid modeling method is adopted, specifically: A basic model of aging effects is established, including a defect type influence coefficient, a time influence factor, and a comprehensive adjustment coefficient. The defect type influence coefficient is used to quantify the degree of differentiated influence of different joint defect types on the electric field distortion of the cable body. The time influence factor is used to characterize the aging effect rate of the middle cable joint on the cable bodies on both sides as the aging time increases. The comprehensive adjustment coefficient is used to characterize the comprehensive correction effect of factors other than electric field distortion and increased local thermal resistance on aging transmission. Using the training sample set, with the goal of minimizing the mean square error between the predicted additional aging increment and the measured additional aging increment, the parameters of the basic model of the aging effect are trained using the nonlinear least squares method to generate the aging effect transmission model.

6. The aging detection method for power cables according to claim 4, characterized in that, Step 3 involves fusing the first aging data with the additional aging increment at the corresponding aging time node, specifically as follows: Step 301: Spatial interpolation is performed on the discrete additional aging increment output by the aging effect transmission model, and a continuously distributed aging increment function is established based on the interpolation result. The input of the aging increment function is the axial position of the cable, and the output is the corresponding additional aging increment. Step 302: Obtain the target additional aging increment at the target location through the aging increment function, and superimpose it with the first aging data at the target location to generate optimized aging test results for different axial positions.

7. The aging detection method for power cables according to claim 6, characterized in that, If the target additional aging increment at the target location is inconsistent with the characteristic attributes of the first aging data, then a pre-established mapping model is invoked to perform feature value transformation, and the transformation result is used to perform data fusion to generate optimized aging test results.

8. An aging detection device for power cables, based on the method described in any one of claims 1-7, characterized in that, It includes a first acquisition module, a second acquisition module, and a fusion module. The first acquisition module is used to acquire first aging data of the cable body and second aging data of the intermediate cable joint under preset aging conditions. The first aging data and the second aging data include cable body aging parameters and cable joint aging parameters corresponding to different aging time nodes. The second acquisition module is used to input the second aging data into a pre-established aging effect transmission model and output the additional aging increment of the intermediate cable joint at different axial positions of the cable body at the corresponding aging time node. The fusion module is used to fuse the first aging data and the additional aging increment at the corresponding aging time node to generate optimized aging test results for different axial positions of the cable body.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the aging detection method for the power cable according to any one of claims 1-7.

10. An aging detection device for power cables, comprising a computer-readable storage medium and a processor, characterized in that, When the processor executes the computer program on the computer-readable storage medium, it implements the steps of the aging detection method for the power cable according to any one of claims 1-7.

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