A method of determining the number of dielectric response types in an insulating material
By performing piecewise linear fitting on low-frequency dielectric constant data points of insulating materials, the number of dielectric response types can be quickly determined, solving the problem that the number of dielectric response types is difficult to determine in existing technologies. This enables rapid dielectric response analysis and promotes online detection and life prediction of power equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ELECTRIC POWER RES INST OF GUANGXI POWER GRID CO LTD
- Filing Date
- 2022-12-02
- Publication Date
- 2026-06-05
AI Technical Summary
Existing technologies cannot quickly and easily determine the number of dielectric response types in insulating materials, which limits the application of dielectric response analysis in the fields of online monitoring and fault diagnosis and life prediction of power equipment.
By performing continuous piecewise linear fitting on low-frequency dielectric constant data points obtained from insulating materials within a certain temperature range and frequency, and reading the number of intersection points of the fitted curves and the data points not crossed by the linear fitting curves, the number of dielectric relaxation types can be determined.
This technology enables rapid identification of the number of dielectric response types, reduces computational load and time costs, and promotes the development of online detection of insulation materials and insulation condition assessment and life prediction for power equipment.
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Figure CN115718221B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of materials testing technology, and in particular to a method for determining the number of types of dielectric responses in insulating materials. Background Technology
[0002] The dielectric constant of insulating materials and the insulation performance of power equipment, such as breakdown field strength and surface flashover voltage, are closely related to the internal molecular structure and the movement behavior of microscopic particles. By analyzing the dielectric response characteristics of materials, the insulation state of power equipment can be determined, and the operation and service life of the equipment can be predicted. The dielectric response characteristics of insulating materials are greatly affected by dielectric relaxation behavior, and there are usually multiple dielectric relaxation processes that collectively influence the dielectric response characteristics. When analyzing dielectric response characteristics, the ability to quickly determine the number of dielectric relaxation types in the material is crucial. This is also a technical barrier limiting the application and widespread use of dielectric response analysis methods in fields such as online monitoring, fault diagnosis, and life prediction of power equipment. It is an analytical technique urgently needed for development in the field of high-voltage insulation.
[0003] The dielectric response characteristics of insulating materials are influenced by the microscopic molecular behavior. By analyzing the dielectric response characteristics, microscopic parameters of the material's molecular behavior can be obtained, thereby determining the overall macroscopic performance and predicting its remaining lifetime. The dielectric response characteristics of materials are composed of various dielectric polarization or relaxation mechanisms, including transient polarization such as electronic displacement polarization and atomic displacement polarization, and relaxation polarization such as interfacial polarization, dipole polarization, thermionic polarization, and electrode polarization. The dielectric response of materials is more significantly affected by relaxation polarization. Typically, multiple relaxation processes exist within the material, working together to cause changes in the material's dielectric response behavior. To analyze the molecular motion behavior within the material through dielectric response characteristics, it is necessary to separate each relaxation process from the dielectric response curve and analyze individual relaxation processes. Currently, dielectric response functions such as the HN function, CD function, or CC function are mainly used to fit and calculate the dielectric response characteristics of materials. Since a single dielectric response function can only describe a single dielectric relaxation process, the number of dielectric relaxation types within the material must be known when using a dielectric response function to determine the number of dielectric response functions. Existing dielectric calculation methods mainly assume the existence of several relaxation processes in the material, perform iterative calculations based on these assumptions, and compare the results with experimental results. When the calculated results deviate from the experimental results, the assumptions are adjusted, and the iteration is repeated. Finally, the dielectric response characteristics are described mathematically using the dielectric response function. Because existing methods cannot quickly and conveniently determine the number of dielectric relaxation types in insulating materials, the numerical calculation of dielectric term-induced characteristics is extremely time-consuming and labor-intensive, causing significant inconvenience to research and applications and limiting the application of dielectric response analysis in the fields of online monitoring and fault diagnosis, and life prediction of power equipment. Summary of the Invention
[0004] To address the above shortcomings, this invention provides a method for determining the number of dielectric response types in insulating materials, thereby solving the problem of the complexity in determining the number of dielectric response types in insulating materials in the prior art.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A method for determining the number of dielectric response types in an insulating material includes the following steps: performing continuous piecewise linear fitting on low-frequency dielectric constant data points obtained from the insulating material within a certain temperature range and at a certain frequency; obtaining the number of dielectric relaxation types in the insulating material by reading the number of intersections of the fitted curves and adding the data points not crossed by the linear fitted curves; thereby obtaining the number of dielectric response types.
[0007] Furthermore, the number of data points not crossed by the linearly fitted curve is either 0 or 1.
[0008] Furthermore, the temperature range is 20℃-200℃.
[0009] Furthermore, a data point is acquired at regular temperature intervals.
[0010] Furthermore, the temperature interval between adjacent data points is 10℃-20℃.
[0011] Furthermore, the frequency is 0.1 Hz.
[0012] Furthermore, the insulating material is epoxy resin or epoxy resin composite material.
[0013] Furthermore, the specific steps of the continuous piecewise linear fitting are as follows:
[0014] S1. Plot a scatter plot of the relationship between dielectric constant and temperature, with temperature as the x-axis and the obtained low-frequency dielectric constant as the y-axis.
[0015] S2. Using the dielectric constant corresponding to the first temperature as the reference starting point, draw a linear fitting curve that passes through the point and continuously passes through subsequent data points, and denote it as curve 1.
[0016] S3. Starting from the point with the lowest temperature among the dielectric constant data points that curve 1 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 2.
[0017] S4. Starting from the point with the lowest temperature among the dielectric constant data points that curve 2 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 3.
[0018] S5. Continue in this manner until, in the scatter plot, there is at most one point that is not crossed by the linear fitting curve; at this point, n curves are recorded.
[0019] Furthermore, if there is a point in the scatter plot that is not crossed by any linear fitting curve, then the number of dielectric relaxation types in the material is n; if all points in the scatter plot are crossed by the linear fitting curve, then the number of dielectric relaxation types in the material is n-1.
[0020] Compared with the prior art, the beneficial effects of the present invention are: the method for determining the number of dielectric response types in insulating materials provided by the present invention can quickly determine the number of dielectric relaxation types in insulating materials through a simple method, thereby quickly obtaining the number of dielectric response types. This can significantly reduce the computational load and time of dielectric response analysis and calculation, significantly reduce the time cost of dielectric response analysis, and promote the development of research and applications such as online detection of insulating materials, insulation status assessment and life prediction of power equipment. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.
[0022] Figure 1 This is a schematic diagram of the continuous piecewise linear fitting of the relationship between temperature and low-frequency dielectric constant in this invention. Detailed Implementation
[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0024] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.
[0025] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.
[0026] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.
[0027] A preferred embodiment of the present invention provides a method for determining the number of dielectric response types in an insulating material, comprising the following steps: performing continuous piecewise linear fitting on low-frequency dielectric constant data points obtained from epoxy resin composite materials within the range of 20℃-200℃ and at a frequency of 0.1 Hz; obtaining the number of dielectric relaxation types in the insulating material by reading the number of intersection points of the fitted curves and adding the data points not crossed by the linear fitted curves, thereby obtaining the number of dielectric response types.
[0028] Since every two data points can be linearly fitted into a fitted curve, the number of data points not crossed by the linear fitted curve is 0 or 1, that is, at most one data point is not crossed by the linear fitted curve. Therefore, the number of dielectric relaxation types in the insulating material is the number of intersections of the fitted curve plus 0 or 1.
[0029] The temperature range for data acquisition is 20℃-200℃, with data points acquired at regular temperature intervals to ensure a uniform temperature distribution. Furthermore, the temperature interval between data points should be reasonable; preferably, the temperature interval between adjacent data points is 10℃-20℃, with 20℃ being the most preferred.
[0030] The specific steps for continuous piecewise linear fitting are as follows:
[0031] S1. Plot a scatter plot of the relationship between dielectric constant and temperature, with temperature as the x-axis and the obtained low-frequency dielectric constant as the y-axis.
[0032] S2. Using the dielectric constant corresponding to the first temperature as the reference starting point, draw a linear fitting curve that passes through the point and continuously passes through subsequent data points, and denote it as curve 1.
[0033] S3. Starting from the point with the lowest temperature among the dielectric constant data points that curve 1 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 2.
[0034] S4. Starting from the point with the lowest temperature among the dielectric constant data points that curve 2 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 3.
[0035] S5. Continue in this manner until, in the scatter plot, there is at most one point that is not crossed by the linear fitting curve; at this point, n curves are recorded.
[0036] If there is a point in the scatter plot that is not crossed by any linear fitting curve, then the number of dielectric relaxation types in the material is n; if all points in the scatter plot are crossed by the linear fitting curve, then the number of dielectric relaxation types in the material is n-1.
[0037] The method for determining the number of dielectric response types in an insulating material according to the present invention will be further explained below through a specific exemplary embodiment:
[0038] By performing continuous piecewise linear fitting on the low-frequency dielectric constant data points of the insulating material obtained within the temperature range of 20℃-200℃ and at a frequency of 0.1 Hz, please refer to... Figure 1 Specifically:
[0039] S1. Plot a scatter plot of the relationship between dielectric constant and temperature, with temperature as the x-axis and the low-frequency dielectric constant obtained at 0.1Hz as the y-axis.
[0040] S2. Using the dielectric constant corresponding to 20℃ as the reference starting point, draw a linear fitting curve that passes through this point and continuously crosses subsequent data points. This linear fitting curve is a straight line parallel to the x-axis, denoted as curve 1. Figure 1 As shown, curve 1 passes through the data points of dielectric constant corresponding to 20℃, 40℃, 60℃ and 80℃;
[0041] S3. Taking the lowest temperature point among the dielectric constant data points that curve 1 does not pass through in the scatter plot as the starting point, that is, taking the dielectric constant data point corresponding to 100 ℃ as the starting point, draw a linear fitting curve through the next point (the dielectric constant data point corresponding to 120 ℃), and denote it as curve 2. At this time, curve 2 extends and passes through the dielectric constant data point corresponding to 140 ℃. Then, curve 2 passes through the dielectric constant data points corresponding to 100 ℃, 120 ℃ and 140 ℃ in total.
[0042] S4. Taking the lowest temperature point among the dielectric constant data points that curve 2 does not pass through in the scatter plot as the starting point, that is, taking the dielectric constant data point corresponding to 160 ℃ as the starting point, draw a linear fitting curve through the next point (the dielectric constant data point corresponding to 180 ℃), and denote it as curve 3. At this time, curve 2 does not pass through the dielectric constant data points when it extends backward. Then, curve 3 passes through the dielectric constant data points corresponding to 160 ℃ and 180 ℃ in total.
[0043] 5) In the scatter plot, the last data point of the dielectric constant corresponding to 200 ℃ is left. Since it cannot be fitted into a linear fitting curve, the data point of the dielectric constant corresponding to 200 ℃ is the only point that is not crossed by the curve and does not need to be fitted further.
[0044] like Figure 1As shown, there are 3 curves in total. There is one point (the data point of dielectric constant corresponding to 200 ℃) that is not crossed by any curve. The number of intersection points of the fitted curves is 2. In addition, there is 1 data point that is not crossed by the linear fitted curve. Therefore, there are a total of 3 dielectric relaxation behaviors. The number of dielectric relaxation types of insulating materials is 3, that is, the number of dielectric response types is 3.
[0045] Electrical relaxation constitutes the dielectric response behavior, and the increase or decrease of the types of dielectric relaxation will lead to a significant change in the dielectric constant. At low frequencies, dielectric relaxation is more likely to occur in materials. Therefore, this invention determines the number of dielectric relaxation types in the material by judging the change in the dielectric constant at low frequencies, and thus obtains the number of dielectric response types.
[0046] The method for determining the number of dielectric response types in insulating materials provided by this invention can quickly determine the number of dielectric relaxation types in insulating materials through a simple method, thereby rapidly obtaining the number of dielectric response types. This can significantly reduce the computational load and time of dielectric response analysis and calculation, greatly reduce the time cost of dielectric response analysis, and promote the development of research and applications such as online detection of insulating materials, insulation condition assessment and life prediction of power equipment.
[0047] Those skilled in the art will recognize that the units of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components of the various examples have been generally described in terms of functionality in the foregoing description. 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 the invention.
[0048] In the embodiments provided in this application, it should be understood that the division of units is only a logical functional division. In actual implementation, there may be other division methods, such as multiple units can be combined into one unit, one unit can be split into multiple units, or some features can be ignored.
[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.
Claims
1. A method for determining the number of types of dielectric responses in an insulating material, characterized in that, Includes the following steps: By continuously performing piecewise linear fitting on the low-frequency dielectric constant data points of the insulating material within a certain temperature range and at a certain frequency, and by reading the number of intersections of the fitted curves and adding the data points that were not crossed by the linear fitted curves, the number of dielectric relaxation types of the insulating material is obtained, thereby obtaining the number of dielectric response types. The specific steps of the continuous piecewise linear fitting are as follows: S1. Plot a scatter plot of the relationship between dielectric constant and temperature, with temperature as the x-axis and the obtained low-frequency dielectric constant as the y-axis. S2. Using the dielectric constant corresponding to the first temperature as the reference starting point, draw a linear fitting curve that passes through the point and continuously passes through subsequent data points, and denote it as curve 1. S3. Starting from the point with the lowest temperature among the dielectric constant data points that curve 1 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 2. S4. Starting from the point with the lowest temperature among the dielectric constant data points that curve 2 does not pass through in the scatter plot, draw a linear fitting curve through the next point, which is denoted as curve 3. S5. Continue in this manner until, in the scatter plot, at most one point is not crossed by the linearly fitted curve; at this point, n curves are recorded; among them... If there is a point in the scatter plot that is not crossed by any linear fitting curve, then the number of dielectric relaxation types in the material is n; if all points in the scatter plot are crossed by the linear fitting curve, then the number of dielectric relaxation types in the material is n-1.
2. The method for determining the number of types of dielectric responses in an insulating material according to claim 1, characterized in that, The number of data points not crossed by the linearly fitted curve is 0 or 1.
3. The method for determining the number of types of dielectric responses in an insulating material according to claim 1, characterized in that, The temperature range is 20℃-200℃.
4. The method for determining the number of types of dielectric responses in an insulating material according to claim 3, characterized in that, A data point is acquired at regular temperature intervals.
5. The method for determining the number of types of dielectric responses in an insulating material according to claim 4, characterized in that, The temperature interval between adjacent data points is 10℃-20℃.
6. The method for determining the number of types of dielectric responses in an insulating material according to claim 1, characterized in that, The frequency is 0.1 Hz.
7. The method for determining the number of types of dielectric responses in an insulating material according to claim 1, characterized in that, The insulating material is epoxy resin or epoxy resin composite material.