Methods and related equipment for assessing the degree of degradation of insulation structures based on dielectric constant

Abstract

This application discloses a method and related equipment for evaluating the degree of insulation structure degradation based on dielectric constant, relating to the field of cable quality testing technology. The method obtains a scattering vector based on a first dielectric constant, a second dielectric constant, and scattering intensity, effectively decoupling the coupling effect between interface phase thickness variation and material degradation. The optimal interface phase thickness parameter is optimized and screened through scattering intensity and scattering vector. The optimal interface phase thickness parameter can accurately characterize the microstructural degradation state of the cable insulation. Therefore, using the optimal interface phase thickness parameter to evaluate the structural degradation degree of the cable insulation material can accurately reflect the degradation status of the cable insulation material.

Description

Technical Field

[0001] This invention relates to the field of cable quality testing technology, and in particular to a method and related equipment for assessing the degree of insulation structure deterioration based on dielectric constant. Background Technology

[0002] The interfacial phase thickness of cable insulation materials is a key parameter affecting their electrical performance and mechanical stability. Traditional testing methods, such as microscopic observation or ultrasonic measurement, are insufficient to accurately characterize the interfacial phase thickness and its degradation state at the micro-nano scale. In particular, when cable insulation materials undergo changes in dielectric constant or microstructural damage due to long-term operation, existing technologies cannot effectively distinguish the coupled effects of changes in interfacial phase thickness and material degradation, leading to significant errors in the evaluation results. Summary of the Invention

[0003] In view of this, the present invention provides a method and related equipment for evaluating the degree of degradation of insulation structures based on dielectric constant.

[0004] The specific technical solution of the first embodiment of the present invention is as follows: a method for evaluating the degree of insulation structure degradation based on dielectric constant, the method comprising: performing a small-angle scattering experiment on the cable insulation material to be evaluated to obtain the scattering intensity of the cable insulation material to be evaluated; obtaining the first dielectric constant of the first interface layer of the cable insulation material to be evaluated, and the second dielectric constant of the second interface layer of a standard cable insulation material that has not undergone degradation; obtaining the scattering vector of the scattering intensity based on the first dielectric constant, the second dielectric constant, and the scattering intensity; selecting the optimal interface phase thickness parameter from a plurality of preset interface phase thickness parameters based on the scattering intensity and the scattering vector; the optimal interface phase thickness parameter being the actual interface phase thickness parameter of the cable insulation material to be evaluated; the interface phase thickness parameter being the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material; and evaluating the degree of structural degradation of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter.

[0005] Preferably, the scattering vector of the scattering intensity is obtained using the following formula:

[0006]

[0007] in, The scattering intensity, For the first interface layer in position The first dielectric constant and the second interface layer at position The difference in the second dielectric constant, It is an imaginary number. Let be the scattering vector.

[0008] Preferably, the step of selecting the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector includes: constructing a first relationship curve between the scattering intensity, the scattering vector, and the interface phase thickness parameter of the cable insulation material to be evaluated; and determining the optimal interface phase thickness parameter among the different preset interface phase thickness parameters using different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range.

[0009] Preferably, the step of determining the optimal interface phase thickness parameter among the different preset interface phase thickness parameters using different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range includes: correcting the first relationship curve using different preset interface phase thickness parameters to obtain a second relationship curve corresponding to each preset interface phase thickness parameter; fitting the second relationship curve within a preset scattering vector range to obtain a fitted straight line for each second relationship curve; and determining the optimal interface phase thickness parameter based on the fitted straight line and the second relationship curve.

[0010] Preferably, the preset scattering vector range is obtained by the following method: obtaining the scattering vector range corresponding to the structure of the cable insulation material to be evaluated at the microscopic level; the square of the scattering vector range constitutes the preset scattering vector range.

[0011] Preferably, the first relationship curve is obtained using the following formula:

[0012]

[0013] in, As a preset constant, The correlation distance is a measure of the inhomogeneity of a two-phase system. The interface phase thickness parameter. The scattering vector, The scattering intensity is denoted as .

[0014] Preferably, the step of evaluating the structural degradation degree of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter includes: obtaining the transition interface phase thickness of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter; the transition interface phase thickness is the thickness of the transition interface from the crystalline region to the amorphous region of the cable insulation material to be evaluated; evaluating the structural degradation degree of the cable insulation material to be evaluated based on the transition interface phase thickness and a preset evaluation rule; wherein, the preset evaluation rule includes that the smaller the transition interface phase thickness, the more severe the structural degradation degree of the cable insulation material to be evaluated, and the larger the transition interface phase thickness, the less severe the structural degradation degree of the cable insulation material to be evaluated.

[0015] The specific technical solution of the second embodiment of the present invention is as follows: an insulation structure degradation assessment system based on dielectric constant, the system comprising: a scattering intensity acquisition module, a dielectric constant acquisition module, a scattering vector acquisition module, an optimal selection module, and an assessment module; the scattering intensity acquisition module is used to perform a small-angle scattering experiment on the cable insulation material to be assessed to obtain the scattering intensity of the cable insulation material to be assessed; the dielectric constant acquisition module is used to obtain the first dielectric constant of the first interface layer of the cable insulation material to be assessed, and the second dielectric constant of the second interface layer of a standard cable insulation material that has not undergone degradation; the scattering vector acquisition module is used to obtain the scattering vector of the scattering intensity based on the first dielectric constant, the second dielectric constant, and the scattering intensity; the optimal selection module is used to select the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector; the optimal interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be assessed; the interface phase thickness parameter is the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material; the assessment module is used to assess the structural degradation degree of the cable insulation material to be assessed based on the optimal interface phase thickness parameter.

[0016] The specific technical solution of the third embodiment of the present invention is as follows: an insulation structure degradation assessment device based on dielectric constant, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0017] The specific technical solution of the fourth embodiment of the present invention is as follows: a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0018] Implementing the embodiments of the present invention will have the following beneficial effects:

[0019] This invention obtains the scattering intensity through small-angle scattering experiments and derives the scattering vector by combining the first dielectric constant of the insulation material to be evaluated with the second dielectric constant of a standard insulation material. Based on the scattering intensity and scattering vector, the optimal interface phase thickness parameter is selected from multiple preset interface phase thickness parameters. The degree of structural degradation of the cable insulation material to be evaluated is then assessed based on the optimal interface phase thickness parameter. Different degrees of degradation result in different material structures and interface phase thicknesses, leading to different dielectric constants and scattering intensities. Therefore, obtaining the scattering vector based on the first dielectric constant, the second dielectric constant, and the scattering intensity effectively decouples the coupling effect between interface phase thickness variations and material degradation. By optimizing and selecting the optimal interface phase thickness parameter through scattering intensity and scattering vector, the optimal interface phase thickness parameter can accurately characterize the microstructural degradation state of the cable insulation. Therefore, using the optimal interface phase thickness parameter to assess the degree of structural degradation of the cable insulation material to be evaluated can accurately reflect the degradation status of the cable insulation material. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 The flowchart shows the steps of the method for assessing the degree of degradation of insulation structures based on dielectric constant.

[0022] Figure 2 A schematic diagram of the scattering intensity curves of cable insulation materials after different heat treatment times;

[0023] Figure 3 This is a schematic diagram of the second relationship curve after correction for cable insulation material that has not undergone heat treatment;

[0024] Figure 4 This is a schematic diagram of the second relationship curve after correction of cable insulation materials subjected to different heat treatment times;

[0025] Figure 5 This is a schematic diagram showing the thickness variation of the interface between the crystalline and amorphous regions of cable insulation material at different heat treatment stages.

[0026] Figure 6 This is a schematic diagram of a system for assessing the degree of insulation structure degradation based on dielectric constant.

[0027] Among them, 201 is the scattering intensity acquisition module; 202 is the dielectric constant acquisition module; 203 is the scattering vector acquisition module; 204 is the optimal selection module; and 205 is the evaluation module. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0029] The terms "first," "second," etc., used in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or modules is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to such processes, methods, products, or apparatus.

[0030] 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 this application. 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.

[0031] Please see Figure 1 This is a flowchart illustrating the steps of a method for assessing the degree of insulation structure degradation based on dielectric constant in the first embodiment of this application. The method accurately reflects the degradation of cable insulation materials and includes:

[0032] Step 101: Perform a small-angle scattering experiment on the cable insulation material to be evaluated to obtain the scattering intensity of the cable insulation material to be evaluated;

[0033] Step 102: Obtain the first dielectric constant of the first interface layer of the cable insulation material to be evaluated, and the second dielectric constant of the second interface layer of the standard cable insulation material that has not deteriorated;

[0034] Step 103: Obtain the scattering vector of the scattering intensity based on the first dielectric constant, the second dielectric constant, and the scattering intensity;

[0035] Step 104: Based on the scattering intensity and the scattering vector, select the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters; the optimal interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be evaluated; the interface phase thickness parameter is the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material.

[0036] Step 105: Evaluate the degree of structural degradation of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter.

[0037] Specifically, small-angle scattering experiments are used to test the insulation material of the cable under evaluation, accurately acquiring its scattering intensity distribution data. Simultaneously, the first dielectric constant of the insulation material is collected, and the second dielectric constant of a standard cable insulation material that has not undergone degradation is also obtained. Based on the scattering intensity data and the first and second dielectric constants, a scattering vector is obtained. Based on the scattering vector and scattering intensity, the optimal interface phase thickness parameter is selected from multiple preset interface phase thickness parameters. The optimal thickness parameter is then compared with the interface phase thickness of the standard cable insulation material. If the thickness parameter significantly deviates from the standard value, it indicates that the interface layer structure of the cable insulation material under evaluation has degraded. This method, which combines experimental data with a theoretical model, ensures that the determined optimal interface phase thickness parameter is closer to actual conditions.

[0038] The method in this embodiment obtains the scattering intensity through a small-angle scattering experiment, and derives the scattering vector by combining the first dielectric constant of the insulation material to be evaluated with the second dielectric constant of the standard insulation material. Based on the scattering intensity and scattering vector, the optimal interface phase thickness parameter is selected from multiple preset interface phase thickness parameters. The structural degradation degree of the cable insulation material to be evaluated is then assessed based on the optimal interface phase thickness parameter. Different degrees of degradation result in different material structures and interface phase thicknesses, leading to different dielectric constants and scattering intensities. Therefore, obtaining the scattering vector based on the first dielectric constant, the second dielectric constant, and the scattering intensity effectively decouples the coupling effect between interface phase thickness changes and material degradation. By optimizing and selecting the optimal interface phase thickness parameter through scattering intensity and scattering vector, the optimal interface phase thickness parameter can accurately characterize the microstructural degradation state of the cable insulation. Therefore, using the optimal interface phase thickness parameter to assess the structural degradation degree of the cable insulation material to be evaluated can accurately reflect the degradation status of the cable insulation material.

[0039] In a specific embodiment, the scattering vector of the scattering intensity is obtained using the following formula:

[0040]

[0041] in, The scattering intensity, For the first interface layer in position The first dielectric constant and the second interface layer at position The difference in the second dielectric constant, It is an imaginary number. The scattering vector is defined as follows. Specifically, it is based on the location of the first interface layer. The first dielectric constant and the second interface layer at position The difference in the second dielectric constant and other parameters can be used to calculate the scattering vector related to the interface phase thickness more accurately. This helps to extract information related to the key structural parameter of the interface phase thickness from complex scattering signals, thus laying the foundation for determining the optimal interface phase thickness parameter.

[0042] In a specific embodiment, the step of selecting the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector includes: constructing a first relationship curve between the scattering intensity, the scattering vector, and the interface phase thickness parameter of the cable insulation material to be evaluated; and determining the optimal interface phase thickness parameter among the different preset interface phase thickness parameters using different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range.

[0043] Specifically, construct the scattering intensity I ( q ), scattering vector q Interfacial phase thickness parameters of the cable insulation material to be evaluated The first relationship curve between them; starting from 0 and gradually increasing, taking different values... The value is then used to correct the first relationship curve within a preset scattering vector range to determine the optimal interface phase thickness parameter. The degree of structural degradation of the cable insulation material to be evaluated is determined based on the optimal interface phase thickness parameters.

[0044] In a specific embodiment, determining the optimal interface phase thickness parameter among the different preset interface phase thickness parameters using different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range includes: correcting the first relationship curve using different preset interface phase thickness parameters to obtain a second relationship curve corresponding to each preset interface phase thickness parameter; fitting the second relationship curve within a preset scattering vector range to obtain a fitted straight line for each second relationship curve; and determining the optimal interface phase thickness parameter based on the fitted straight line and the second relationship curve.

[0045] Specifically, the obtained first relationship curve is corrected. The correction method is as follows: starting from 0 and gradually increasing, different values ​​are selected... Different second relationship curves are obtained. A linear fit is then performed on the obtained second relationship curves using a preset interface phase thickness parameter. The optimal interface phase thickness parameter is obtained when the standard deviation of the linear fit is minimized. .

[0046] In a specific embodiment, the crystal structure corresponding to the insulating material is characterized. Linear fitting is performed on the value range to obtain different The fitted straight line of the corresponding second relationship curve is used to iterate through all preset interface phase thickness parameters. The second relationship curve that minimizes the standard deviation is selected as the optimal relationship curve, and the corresponding target preset interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be evaluated. If multiple candidate parameters have similar standard deviations, a consistency constraint on the scattering intensity gradient is further introduced (e.g., the deviation between the scattering intensity gradient ∇I(q) and the theoretical gradient is less than 10%). Through the constraints on the scattering vector range and the evaluation of the goodness of fit, the influence of noise interference on the thickness parameter inversion is effectively reduced, and the robustness and accuracy of the interface phase thickness screening are improved.

[0047] In a specific embodiment, the preset scattering vector range is obtained by the following method: obtaining the scattering vector range corresponding to the structure of the cable insulation material to be evaluated at the microscopic level; the square value of the scattering vector range constitutes the preset scattering vector range.

[0048] Specifically, cable insulation materials of different types have significant differences in microstructure. By first determining the insulation material of the cable to be evaluated, then obtaining the corresponding scattering vector range based on the material's microstructure, and using the square of this range to form the preset scattering vector range, this method fully considers the influence of material properties on the scattering vector, making the preset scattering vector range closely related to the actual characteristics of the cable to be evaluated.

[0049] In a specific embodiment, the first relationship curve is obtained using the following formula:

[0050]

[0051] in, As a preset constant, The correlation distance is a measure of the inhomogeneity of a two-phase system. The interface phase thickness parameter. The scattering vector, The scattering intensity is denoted as .

[0052] Specifically, through the scattering vector With scattering intensity The coupling relationship will affect the interface phase thickness parameters. The (interfacial phase thickness inhomogeneity parameter) is directly correlated with scattering experimental data, enabling quantitative inversion from scattering signals to microstructural parameters, overcoming the limitations of traditional methods that rely solely on empirical comparisons. (Exponential term) Introduced The attenuation effect on scattering intensity can effectively suppress high-frequency noise (large). q The interference of the value region on thickness inversion is reduced, improving the accuracy of parameter selection under low signal-to-noise ratio conditions. Correlation distance As a measure characterizing the inhomogeneity of the microstructure of the interface layer, it is obtained through the formula... Term and scattering vector The secondary correlation can sensitively capture the spatial correlation of electron density fluctuations within the interfacial phase, providing crucial information for assessing the degree of degradation of insulating materials (such as local defects or uneven aging). Preset constants. The formula can be flexibly adjusted to adapt to the microstructure regularity of different cable materials (such as polyethylene, cross-linked polyethylene, etc.), making the formula universal, and can be calibrated experimentally. and This can further optimize the accuracy of thickness screening.

[0053] In a specific embodiment, evaluating the structural degradation degree of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter includes: obtaining the transition interface phase thickness of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter; the transition interface phase thickness is the thickness of the transition interface from the crystalline region to the amorphous region of the cable insulation material to be evaluated; evaluating the structural degradation degree of the cable insulation material to be evaluated based on the transition interface phase thickness and a preset evaluation rule; wherein, the preset evaluation rule includes that the smaller the transition interface phase thickness, the more severe the structural degradation degree of the cable insulation material to be evaluated, and the larger the transition interface phase thickness, the less severe the structural degradation degree of the cable insulation material to be evaluated.

[0054] Specifically, an intuitive quantitative evaluation index was established by leveraging the positive correlation between the thickness of the transition interface phase and the degree of structural degradation. When the thickness of the transition interface phase decreases, it indicates that the boundary between the crystalline and amorphous regions is blurred and the disorder of chain segment arrangement increases (such as crystalline region destruction caused by thermal aging or electrical stress), directly reflecting the intensified microstructural degradation of the insulating material. Conversely, a larger thickness indicates a denser interface structure and higher crystal integrity. This rule simplifies the degradation diagnosis logic and avoids the complexity of multi-parameter comprehensive analysis required by traditional methods.

[0055] Specifically, the following is an example of assessing the degree of insulation structure degradation based on dielectric constant:

[0056] 1. Sample Preparation: In this embodiment, the XLPE layer of 500kV cable insulation was selected as the sample. XLPE samples with a thickness between 0.2 and 0.4 mm were obtained by circumferential cutting. The samples were cleaned in an ultrasonic cleaner containing anhydrous ethanol for 30 minutes and then dried in a 60℃ oven for 4 hours. Several samples were then heat-treated at 135℃ for 336 h, 672 h, 1008 h, and 1344 h. Square samples with a width of approximately 10 mm were cut from the samples for later use. The first dielectric constant of the first interface layer of the sample and the second dielectric constant of the second interface layer of the standard cable insulation material that has not deteriorated were obtained.

[0057] 2. X-ray scattering test on the sample: The test angle range was set to 0°~4°, and the wavelength of the double-slit collimated Cu-Kα X-ray source was λ=1.542 Å. The acquired scattering image was subtracted from the background scattering and then integrated. The scattering intensity vector was obtained using the first dielectric constant, the second nodal constant, and the scattering intensity. The scattering vector was then obtained. For scattering intensity One-dimensional curves such as Figure 2 As shown, by Figure 2 It can be seen that as the heat treatment time increases, the scattering intensity peak first increases and then decreases.

[0058] 3. The obtained scattering intensity The parameters are mathematically transformed to obtain the square of the scattering vector. right The change curve, the mathematical transformation is based on the Debye formula for small-angle scattering in the quasi-two-phase structure of semi-crystalline polymers, and the scattering intensity. and scattering vector Establish the following relationship:

[0059]

[0060] 4. Regarding the obtained The curve is corrected. The correction method is as follows: starting from 0, select different values ​​successively from small to large. Worth getting different The obtained curve represents the XLPE crystal structure. A linear fit is performed on the value range, and the desired result is obtained when the standard deviation of the linear fit is minimized. value. Figure 3 This indicates the XLPE test without heat treatment. The corrected curve changes as the value increases from 2.24 to 2.30. The corrected curve characterizes the XLPE crystal structure. Linear fitting was performed on values ​​in the range of 0.20 to 0.80, and the value was determined based on minimizing the standard deviation (root mean square error) of the fit. The values ​​and the standard deviation of the fit are shown in Table 1. It can be seen that when The error is minimized when the value is 2.27, so this value is selected. The value is what we are looking for. value.

[0061] Table 1: Standard deviation of the square of the optimal interfacial phase thickness parameters for different interface phase parameters in untreated cable insulation

[0062]

[0063] Using the same method, XLPE samples were subjected to different heat treatment stages. The curve is corrected to obtain the required result. Value, result as Figure 4 As shown, by Figure 4 It can be seen that after the curve is corrected, The linear relationship is more obvious in the range of 0.2-0.8.

[0064] 5. Calculate the thickness of the transition interface phase from the XLPE crystalline region to the amorphous region based on the obtained σ value. The calculation formula is as follows: .

[0065] The calculation results are as follows Figure 5 As shown, after short-term heat treatment, the XLPE sample exhibits a recrystallization effect, causing some amorphous molecular chains to fold and rearrange into the crystalline region, resulting in an increase in the thickness of the transition interface. This indicates that the XLPE molecular chain arrangement tends towards regularity in the early stage of heat treatment, improving its microstructure quality rather than deteriorating it. However, with increasing heat treatment time, the XLPE molecular chains are gradually destroyed, crystalline defects increase, and the transition interface thickness decreases, leading to a gradual deterioration of the XLPE microstructure. Therefore, the degree of microstructure deterioration can be accurately assessed based on the change in the transition interface thickness (E value). The higher the value, the less the microstructure of XLPE deteriorates and the better the performance and quality of XLPE. The smaller the value, the more severe the degradation of the XLPE microstructure and the worse its performance and quality.

[0066] In a specific embodiment, the second embodiment of this application provides a schematic diagram of a system for assessing the degree of insulation structure degradation based on dielectric constant. The system includes: a scattering intensity acquisition module 201, a dielectric constant acquisition module 202, a scattering vector acquisition module 203, an optimal selection module 204, and an evaluation module 205. The scattering intensity acquisition module 201 is used to perform a small-angle scattering experiment on the cable insulation material to be evaluated to obtain the scattering intensity of the cable insulation material. The dielectric constant acquisition module 202 is used to obtain the first dielectric constant of the first interface layer of the cable insulation material to be evaluated, and the second dielectric constant of the second interface layer of a standard cable insulation material that has not undergone degradation. The scattering vector acquisition module 203 is used to obtain the scattering vector of the scattering intensity based on the first dielectric constant, the second dielectric constant, and the scattering intensity; the optimal selection module 204 is used to select the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector; the optimal interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be evaluated; the interface phase thickness parameter is the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material; the evaluation module 205 is used to evaluate the degree of structural degradation of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter.

[0067] In this embodiment, the system obtains the scattering intensity through a small-angle scattering experiment and derives the scattering vector by combining the first dielectric constant of the insulation material to be evaluated with the second dielectric constant of a standard insulation material. Based on the scattering intensity and scattering vector, the optimal interface phase thickness parameter is selected from multiple preset interface phase thickness parameters. The structural degradation degree of the cable insulation material to be evaluated is then assessed based on the optimal interface phase thickness parameter. Different degrees of degradation result in different material structures and interface phase thicknesses, leading to different dielectric constants and scattering intensities. Therefore, obtaining the scattering vector based on the first dielectric constant, the second dielectric constant, and the scattering intensity effectively decouples the coupling effect between interface phase thickness variations and material degradation. By optimizing and selecting the optimal interface phase thickness parameter through scattering intensity and scattering vector, the optimal interface phase thickness parameter can accurately characterize the microstructural degradation state of the cable insulation. Therefore, using the optimal interface phase thickness parameter to assess the structural degradation degree of the cable insulation material to be evaluated can accurately reflect the degradation status of the cable insulation material.

[0068] In a specific embodiment, the third embodiment of this application provides an insulation structure degradation assessment device based on dielectric constant, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0069] In a specific embodiment, the fourth embodiment of this application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method as described in any one of the first embodiments of this application.

[0070] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for assessing the degree of degradation of an insulating structure based on its dielectric constant, characterized in that, The method includes: A small-angle scattering experiment was conducted on the cable insulation material to be evaluated to obtain the scattering intensity of the cable insulation material to be evaluated; Obtain the first dielectric constant of the first interface layer of the cable insulation material to be evaluated, and the second dielectric constant of the second interface layer of the standard cable insulation material that has not deteriorated; The scattering vector of the scattering intensity is obtained based on the first dielectric constant, the second dielectric constant, and the scattering intensity. Based on the scattering intensity and the scattering vector, the optimal interface phase thickness parameter is selected from multiple preset interface phase thickness parameters; the optimal interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be evaluated; the interface phase thickness parameter is the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material. The structural degradation degree of the cable insulation material to be evaluated is determined based on the optimal interface phase thickness parameter. The scattering vector of the scattering intensity is obtained using the following formula: in, The scattering intensity, For the first interface layer in position The first dielectric constant and the second interface layer at position The difference in the second dielectric constant, It is an imaginary number. The scattering vector; The step of selecting the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector includes: Construct a first relationship curve between the scattering intensity, the scattering vector, and the interface phase thickness parameter of the cable insulation material to be evaluated; By utilizing different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range, the optimal interface phase thickness parameter is determined from among the different preset interface phase thickness parameters; The first relationship curve is obtained using the following formula: in, As a preset constant, The correlation distance is a measure of the inhomogeneity of a two-phase system. The interface phase thickness parameter. The scattering vector, The scattering intensity is denoted as .

2. The method for evaluating the degree of degradation of insulation structures based on dielectric constant as described in claim 1, characterized in that, The step of determining the optimal interface phase thickness parameter among different preset interface phase thickness parameters, the first relationship curve, and a preset scattering vector range includes: The first relationship curve is corrected by using different preset interface phase thickness parameters to obtain a second relationship curve corresponding to each preset interface phase thickness parameter; The second relationship curve is fitted within a preset scattering vector range to obtain a fitted straight line for each second relationship curve; The optimal interface phase thickness parameters are determined based on the fitted straight line and the second relationship curve.

3. The method for evaluating the degree of degradation of insulation structures based on dielectric constant as described in claim 2, characterized in that, The preset scattering vector range is obtained using the following method: The scattering vector range corresponding to the structure is obtained based on the microscopic structure of the cable insulation material to be evaluated. The square of the scattering vector range constitutes the preset scattering vector range.

4. The method for assessing the degree of degradation of insulation structures based on dielectric constant as described in claim 1, characterized in that, The assessment of the structural degradation degree of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter includes: The transition interface phase thickness of the cable insulation material to be evaluated is obtained based on the optimal interface phase thickness parameter; the transition interface phase thickness is the thickness of the transition interface between the crystalline region and the amorphous region of the cable insulation material to be evaluated. The structural degradation degree of the cable insulation material to be evaluated is assessed based on the transition interface phase thickness and preset evaluation rules; wherein, the preset evaluation rules include that the smaller the transition interface phase thickness, the more severe the structural degradation degree of the cable insulation material to be evaluated, and the larger the transition interface phase thickness, the less severe the structural degradation degree of the cable insulation material to be evaluated.

5. A system for assessing the degree of insulation structure degradation based on dielectric constant, employing the method for assessing the degree of insulation structure degradation based on dielectric constant as described in claim 1, characterized in that, The system includes: a scattering intensity acquisition module, a dielectric constant acquisition module, a scattering vector acquisition module, an optimal selection module, and an evaluation module; The scattering intensity acquisition module is used to perform a small-angle scattering experiment on the cable insulation material to be evaluated, and to obtain the scattering intensity of the cable insulation material to be evaluated. The dielectric constant acquisition module is used to acquire the first dielectric constant of the first interface layer of the cable insulation material to be evaluated, and the second dielectric constant of the second interface layer of the standard cable insulation material that has not deteriorated. The scattering vector acquisition module is used to obtain the scattering vector of the scattering intensity based on the first dielectric constant, the second dielectric constant, and the scattering intensity; The optimal selection module is used to select the optimal interface phase thickness parameter from multiple preset interface phase thickness parameters based on the scattering intensity and the scattering vector; the optimal interface phase thickness parameter is the actual interface phase thickness parameter of the cable insulation material to be evaluated; the interface phase thickness parameter is the thickness of the transition region between the crystalline phase and the adjacent amorphous phase of the cable insulation material. The evaluation module is used to evaluate the degree of structural degradation of the cable insulation material to be evaluated based on the optimal interface phase thickness parameter.

6. A device for assessing the degree of degradation of insulation structures based on dielectric constant, comprising a memory and a processor, characterized in that, The memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of the method as described in any one of claims 1 to 4.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 4.

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