Residual life prediction method and device for capacitor equipment

Abstract

The invention discloses a residual life prediction method and device for capacitor equipment, and belongs to the technical field of equipment test.The method comprises the steps that structural parameters, inherent characteristic parameters and actually-measured dielectric loss values of the tested capacitor equipment and actually-measured voltage data in a preset time period are obtained; calculating a dielectric constant reference value according to the structure parameters; constructing a multi-physics field coupling model based on the dielectric constant reference value and the inherent characteristic parameters, and solving the multi-physics field coupling model to obtain temperature field distribution; extracting time domain features in a preset time period based on the actually measured voltage data, and calculating a voltage ratio of the test capacitor equipment according to the time domain features in the preset time period; correcting the actually measured dielectric loss value based on the voltage ratio to obtain a corrected dielectric loss value; and according to the corrected dielectric loss value and the temperature field distribution, calculating the residual life of the test capacitor equipment. Therefore, by implementing the method, the problem of low residual life prediction accuracy in the prior art can be solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of device testing, in particular to a method and device for predicting the residual life of a capacitor device. BACKGROUND

[0002] The dielectric loss value is one of the core indicators for predicting the residual life of a capacitor, and thus the real-time dielectric loss value of a capacitor device can be used to predict the residual life of the capacitor device. However, when measuring the dielectric loss value, the ideal sinusoidal voltage assumption is usually used, which cannot adapt to the actual voltage of the capacitor device in real time. Fluctuations in the capacitor voltage can affect the original measurement results of the dielectric loss value. Therefore, the accuracy of the prediction of the residual life of the capacitor device based on the measured dielectric loss value cannot be guaranteed. SUMMARY

[0003] The present application provides a method and device for predicting the residual life of a capacitor device, which can solve the problem of low accuracy of residual life prediction in the prior art.

[0004] To solve the above technical problems, the present application provides a method for predicting the residual life of a capacitor device, comprising: obtaining the structural parameters, inherent characteristic parameters, measured dielectric loss value and measured voltage data in a preset time period of a test capacitor device; wherein the structural parameters include plate area and plate spacing; the inherent characteristic parameters include electric field strength, material conductivity, material thermal conductivity, material density, material specific heat capacity and material activation energy; calculating a dielectric constant reference value according to the structural parameters; constructing a multi-physics field coupling model based on the dielectric constant reference value and the inherent characteristic parameters, and solving the multi-physics field coupling model to obtain a temperature field distribution; extracting time domain features in a preset time period based on the measured voltage data, and calculating a voltage ratio of the test capacitor device according to the time domain features in the preset time period; correcting the measured dielectric loss value based on the voltage ratio to obtain a corrected dielectric loss value; calculating the residual life of the test capacitor device according to the corrected dielectric loss value and the temperature field distribution.

[0005] As a preferred scheme, the calculation of the dielectric constant reference value according to the structural parameters comprises: calculating a quantum capacitance reference value based on a preset microwave frequency and a preset quantum number; calculating the inter-plate dielectric volume according to the plate area and the plate spacing; determining the ratio of the quantum capacitance reference value to the inter-plate dielectric volume as the dielectric constant reference value.

[0006] As a preferred solution, the multi-physical field coupling model is specifically: In the formula, is the curl of the magnetic field intensity; is the material conductivity; is the electric field intensity; is the effective dielectric constant; is the dielectric constant reference value; is the first-order medium polarizability; is the third-order nonlinear electric polarizability; is the material density; is the specific heat capacity of the material; is the thermal conductivity of the material; is the temperature field distribution; t is time.

[0007] As a preferred solution, the time domain feature in the preset time period is extracted based on the measured voltage data, and the voltage ratio of the test capacitor device is calculated according to the time domain feature in the preset time period, including: The voltage signal and the sampling frequency of each time point are obtained in the measured voltage data; For each time point, the scale factor is calculated according to the sampling frequency; The time domain feature is calculated based on the voltage signal and the scale factor; The mean value of the time domain feature of the preset time period is calculated, and the maximum time domain feature of the preset time period is determined; The ratio of the maximum time domain feature to the mean value of the time domain feature is determined as the voltage ratio.

[0008] As a preferred solution, the time domain feature in the preset time period is calculated by the following formula: In the formula, is the time domain feature in the preset time period; is the scale factor; is the voltage signal at the moment; is the wavelet complex conjugate; is the time axis coordinate of the voltage signal; t is time.

[0009] As a preferred solution, the measured dielectric loss value is corrected based on the voltage ratio to obtain a corrected dielectric loss value, including: Obtain a plurality of material nonlinear coefficients of different aging reaction levels; According to each of the material nonlinear coefficient, the voltage ratio and the measured dielectric loss value, the corrected dielectric loss value is calculated: wherein, is the corrected dielectric loss value; is the measured dielectric loss value; is the nth order material nonlinearity coefficient; is the aging reaction order; is the voltage ratio.

[0010] As a preferred solution, the calculating the remaining life of the test capacitor device according to the corrected dielectric loss value and the temperature field distribution comprises: calculating a current dielectric loss value growth rate according to the corrected dielectric loss value and the temperature field distribution; calculating the remaining life of the test capacitor device according to a preset dielectric loss value critical value, the corrected dielectric loss value and the current dielectric loss value growth rate.

[0011] As a preferred solution, the current dielectric loss value growth rate is calculated by using the following formula: wherein, is the current dielectric loss value growth rate; is the aging coefficient; is the material activation energy; is the aging reaction rate constant.

[0012] As a preferred solution, the calculating the remaining life of the test capacitor device according to a preset dielectric loss value critical value, the corrected dielectric loss value and the current dielectric loss value growth rate comprises: taking the preset dielectric loss value critical value as an upper limit of integration, taking the corrected dielectric loss value as a lower limit of integration, accumulating a ratio between a dielectric loss value increment and the current dielectric loss value growth rate, and determining an accumulated result as the remaining life of the test capacitor device.

[0013] Correspondingly, the application provides a remaining life prediction device for a capacitor device, comprising a data acquisition module, a reference value calculation module, a temperature field solving module, a time domain characteristic analysis module, a dielectric loss value correction module and a life prediction module. The data acquisition module is used to acquire structural parameters, inherent characteristic parameters, a measured dielectric loss value and measured voltage data in a preset time period of a test capacitor device; wherein the structural parameters comprise plate area and plate spacing; the inherent characteristic parameters comprise electric field intensity, material conductivity, material thermal conductivity, material density, material specific heat capacity and material activation energy. The reference value calculation module is used to calculate a dielectric constant reference value according to the structural parameters. The temperature field solving module is used to construct a multiphysics coupling model based on the dielectric constant reference value and the intrinsic characteristic parameters, and solve the multiphysics coupling model to obtain the temperature field distribution; The time-domain feature analysis module is used to extract time-domain features within a preset time period based on the measured voltage data, and to calculate the voltage ratio of the test capacitor device based on the time-domain features within the preset time period. The dielectric loss correction module is used to correct the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value. The lifetime prediction module is used to calculate the remaining lifetime of the test capacitor device based on the corrected dielectric loss value and the temperature field distribution.

[0014] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: This invention provides a method for predicting the remaining life of a capacitor device. The method involves acquiring the structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the tested capacitor device; calculating a reference dielectric constant value based on the structural parameters; constructing a multiphysics coupling model based on the reference dielectric constant value and inherent characteristic parameters, and solving the multiphysics coupling model to obtain the temperature field distribution; extracting time-domain features within the preset time period based on the measured voltage data, and calculating the voltage ratio of the tested capacitor device based on these time-domain features; correcting the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value; and calculating the remaining life of the tested capacitor device based on the corrected dielectric loss value and the temperature field distribution. This invention obtains the structural parameters and inherent characteristic parameters of the test capacitor device, as well as the measured voltage data and measured dielectric loss value. Based on the structural parameters and inherent characteristic parameters, the temperature field distribution is calculated, and the time-domain characteristics that reflect voltage fluctuations are extracted from the measured voltage data. Then, the measured dielectric loss value is corrected based on the time-domain characteristics so that the corrected dielectric loss value adapts to the actual voltage conditions of the capacitor device. The remaining lifetime is predicted based on the temperature field distribution and the corrected dielectric loss value, taking into account environmental factors and voltage fluctuations, thereby improving the accuracy of the remaining lifetime prediction. Attached Figure Description

[0015] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments 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 from these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating an embodiment of the method for predicting the remaining lifespan of a capacitor device provided by the present invention; Figure 2This is a schematic diagram of one embodiment of the remaining life prediction device for capacitor equipment provided by the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0019] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0020] 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.

[0021] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0022] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0023] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0024] Example 1 See Figure 1 To address the problem of low accuracy in remaining lifetime prediction in existing technologies, an embodiment of the present invention provides a method for predicting the remaining lifetime of a capacitor device. This method includes steps 101 to 106, each step of which is detailed below: Step 101: Obtain the structural parameters, inherent characteristic parameters, measured dielectric loss value, and measured voltage data within a preset time period of the test capacitor device; wherein, the structural parameters include plate area and plate spacing; the inherent characteristic parameters include electric field strength, material conductivity, material thermal conductivity, material density, material specific heat capacity, and material activation energy.

[0025] In this embodiment of the invention, the remaining lifetime prediction of the test capacitor device first involves acquiring data about the device itself, including structural parameters and inherent characteristic parameters. Structural parameters include plate area and plate spacing. Inherent characteristic parameters include the inherent physical field characteristics (electric field strength) of the capacitor device and the inherent characteristics of the materials constituting the capacitor device (material conductivity, thermal conductivity, density, specific heat capacity, and activation energy). Since the remaining lifetime of the test capacitor device needs to be calculated, data that changes over time also needs to be acquired, namely, measured voltage data over a current period and measured dielectric loss values ​​obtained using conventional methods.

[0026] Step 102: Calculate the reference value of dielectric constant based on the structural parameters.

[0027] As a preferred embodiment, calculating the dielectric constant reference value based on the structural parameters includes: The quantum capacitance reference value is calculated based on a preset microwave frequency and a preset quantum number; Calculate the volume of the medium between the electrodes based on the electrode area and the electrode spacing; The ratio of the quantum capacitance reference value to the volume of the dielectric medium between the plates is determined as the dielectric constant reference value.

[0028] In this embodiment of the invention, based on the electrode area A and the electrode spacing d, the formula is used... The reference value of dielectric constant can be calculated. . In the formula, It is a quantum capacitance reference value, which can be calculated based on a preset microwave frequency and a preset quantum number, as well as the electron charge and Planck's constant. In the formula, This serves as a reference value for quantum capacitance. The quantum number is a predefined number, and it is a positive integer. ; To preset the microwave frequency, it can be set to... ; It represents the electron charge. is Planck's constant.

[0029] Step 103: Construct a multiphysics coupling model based on the dielectric constant reference value and the inherent characteristic parameters, and solve the multiphysics coupling model to obtain the temperature field distribution.

[0030] In this embodiment of the invention, based on the calculated reference value of the dielectric constant and the obtained intrinsic characteristic parameters, multiphysics coupling modeling can be performed to construct a multiphysics coupling model, which can be represented by electromagnetic-thermal-mechanical coupling field equations: In the formula, The curl of the magnetic field strength; The electrical conductivity of the material; Electric field strength; The effective dielectric constant; This is the reference value for the dielectric constant; The first-order dielectric polarizability; It is a third-order nonlinear polarization. The density of the material; Specific heat capacity of the material; The thermal conductivity of the material; t represents the temperature field distribution; t represents time.

[0031] In this embodiment of the invention, the multiphysics coupling model simultaneously considers dielectric polarization. and nonlinear effects Compared to traditional single electromagnetic field models, this method can improve the accuracy of calculation results by more than an order of magnitude. Among these improvements is the first-order dielectric polarizability. Complex capacitance at different frequencies can be scanned using a broadband dielectric spectrometer. The calculation shows that: Third-order nonlinear polarization The result is obtained by fitting the change in transmittance after the laser passes through the sample using Z-scan technology. Specifically, according to the formula... Determine the third-order nonlinear polarization imaginary part (Nonlinear absorption), and based on the transmittance peak-to-valley difference and third-order nonlinear polarization. The quantitative relationship between the real parts of the three elements was used to calculate the third-order nonlinear polarization. real part (Nonlinear refraction), thus obtaining the third-order nonlinear polarizability. .in, This represents the normalized transmittance variation. The peak intensity of the incident laser light.

[0032] In this embodiment of the invention, by solving the aforementioned multiphysics coupling model, the temperature field distribution T(x,y,z,t) can be obtained, where x, y, and z represent the horizontal, vertical, and horizontal coordinates of the spatial dimension, respectively, and t is a time variable. T(x,y,z,t) represents the temperature state at different spatial locations (x,y,z) at different times (t). Considering environmental factors and analyzing the temperature field distribution when predicting remaining lifetime can effectively improve the accuracy of remaining lifetime prediction.

[0033] Step 104: Extract time-domain features within a preset time period based on the measured voltage data, and calculate the voltage ratio of the test capacitor device based on the time-domain features within the preset time period.

[0034] In this embodiment of the invention, after obtaining the measured dielectric loss value, the time-domain characteristics of the voltage waveform can be obtained by analyzing the measured voltage data, and then the measured dielectric loss value can be corrected according to the time-domain characteristics to improve the accuracy of remaining lifetime prediction.

[0035] As a preferred embodiment, the time-domain features within a preset time period are extracted based on the measured voltage data, and the voltage ratio of the test capacitor device is calculated based on the time-domain features within the preset time period, including: The voltage signal and sampling frequency at each time point are obtained from the measured voltage data; For each time point, the scaling factor is calculated based on the sampling frequency; Calculate the time-domain features based on the voltage signal and the scaling factor; Calculate the mean of the temporal features of the preset time period, and determine the maximum temporal feature of the preset time period; The ratio of the maximum time-domain feature to the mean of the time-domain features is determined as the voltage ratio.

[0036] As a preferred embodiment, the temporal characteristics within a preset time period are calculated using the following formula: In the formula, The temporal characteristics within a preset time period; Scale factor; for The voltage signal at a given moment; For wavelet complex conjugate; t represents the time axis coordinate of the voltage signal; t is time.

[0037] In this embodiment of the invention, dynamic dielectric loss spectrum analysis can be performed using Morlet wavelet transform to extract time-frequency features corresponding to the measured voltage data. Specifically, the voltage signals at each time point are first acquired. Sampling frequency during dynamic scanning Scale factor With sampling frequency The relationship between the two is: Therefore, in obtaining the sampling frequency at each time point... Then, the scaling factor can be calculated. Combining the voltage signal and the scaling factor, the time-domain characteristics are calculated, thus obtaining the time-domain characteristics at each time point. Among these time-domain characteristics, the maximum time-domain characteristic is determined, and the mean of the time-domain characteristics is calculated. The maximum time-domain characteristic and the mean of the time-domain characteristics are then used to determine the voltage ratio. In the formula, This is the voltage ratio; This is the current voltage value; The reference voltage value; The maximum time-domain feature; This represents the mean of the time-domain features.

[0038] Step 105: Correct the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value.

[0039] As a preferred embodiment, the measured dielectric loss value is corrected based on the voltage ratio to obtain the corrected dielectric loss value, including: Obtain the nonlinear coefficients of materials at several different aging reaction levels; Based on the nonlinear coefficients of each material, the voltage ratio, and the measured dielectric loss value, the corrected dielectric loss value is calculated: In the formula, This is the corrected value for dielectric loss. This is the measured value of the dielectric loss. The nonlinear coefficient of the nth-order material; The aging reaction order; This is the voltage ratio.

[0040] In this embodiment of the invention, the voltage ratio is calculated from the time-domain characteristics of the voltage. Therefore, the measured dielectric loss value can be corrected based on the voltage ratio to adapt to voltage fluctuations. A high-voltage nonlinearity correction term is then introduced for nonlinear correction. First, material nonlinearity coefficients for multiple different aging reaction levels are obtained. It can include The following table provides a detailed description of the nonlinear coefficients of these materials: Based on these material nonlinear coefficients, the corrected dielectric loss value can be calculated, and the error of the traditional linear model can be compensated by a third-order Taylor expansion (for example, the error is reduced from 5% to 0.3% under high pressure).

[0041] Step 106: Calculate the remaining lifespan of the test capacitor device based on the corrected dielectric loss value and the temperature field distribution.

[0042] As a preferred embodiment, the remaining lifespan of the test capacitor device is calculated based on the corrected dielectric loss value and the temperature field distribution, including: The current rate of increase of the dielectric loss value is calculated based on the corrected dielectric loss value and the temperature field distribution. The remaining lifespan of the test capacitor device is calculated based on the preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate.

[0043] In this embodiment of the invention, after obtaining the corrected dielectric loss value and temperature field distribution, the remaining lifespan of the test capacitor device can be calculated. Specifically, the current dielectric loss value growth rate is first calculated based on the corrected dielectric loss value and temperature field distribution. Then, combined with a preset dielectric loss value threshold, the remaining lifespan of the test capacitor device is calculated using the corrected dielectric loss value and the current dielectric loss value growth rate as the data basis.

[0044] As a preferred embodiment, the current dielectric loss growth rate is calculated using the following formula: In the formula, This represents the current rate of increase in dielectric loss, equivalent to the aging rate. The aging coefficient; The activation energy of the material can be taken as 1.2 eV; This is the aging reaction rate constant; denoted as the aging reaction order, characterizing the nonlinear influence of the dielectric loss value tanδ on the aging rate.

[0045] As a preferred embodiment, the remaining lifespan of the test capacitor device is calculated based on a preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate, including: Using a preset dielectric loss threshold as the upper limit of integration and a corrected dielectric loss value as the lower limit of integration, the ratio between the increase in dielectric loss value and the growth rate of dielectric loss value is accumulated, and the accumulated result is determined as the remaining life of the test capacitor equipment.

[0046] In this embodiment of the invention, the remaining lifespan of the test capacitor device can be calculated according to the following formula: In the formula, Remaining lifespan; The preset dielectric loss threshold can be defined based on the constituent materials of the capacitor device; This represents the dielectric loss value. This represents the growth rate of the dielectric loss value.

[0047] Implementing the above embodiments has the following effects: This invention provides a method for predicting the remaining life of a capacitor device. The method involves acquiring the structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the tested capacitor device; calculating a reference dielectric constant value based on the structural parameters; constructing a multiphysics coupling model based on the reference dielectric constant value and inherent characteristic parameters, and solving the multiphysics coupling model to obtain the temperature field distribution; extracting time-domain features within the preset time period based on the measured voltage data, and calculating the voltage ratio of the tested capacitor device based on these time-domain features; correcting the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value; and calculating the remaining life of the tested capacitor device based on the corrected dielectric loss value and the temperature field distribution. This invention obtains the structural parameters and inherent characteristic parameters of the test capacitor device, as well as the measured voltage data and measured dielectric loss value. Based on the structural parameters and inherent characteristic parameters, the temperature field distribution is calculated, and the time-domain characteristics that reflect voltage fluctuations are extracted from the measured voltage data. Then, the measured dielectric loss value is corrected based on the time-domain characteristics so that the corrected dielectric loss value adapts to the actual voltage conditions of the capacitor device. The remaining lifetime is predicted based on the temperature field distribution and the corrected dielectric loss value, taking into account environmental factors and voltage fluctuations, thereby improving the accuracy of the remaining lifetime prediction.

[0048] Example 2 See Figure 2 This is a schematic diagram of an embodiment of the remaining life prediction device for capacitor equipment provided by the present invention. The device includes a data acquisition module, a reference value calculation module, a temperature field solution module, a time domain feature analysis module, a dielectric loss correction module, and a life prediction module. The data acquisition module is used to acquire the structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the test capacitor device; wherein, the structural parameters include plate area and plate spacing; the inherent characteristic parameters include electric field strength, material conductivity, material thermal conductivity, material density, material specific heat capacity, and material activation energy; The reference value calculation module is used to calculate the reference value of dielectric constant based on the structural parameters; The temperature field solving module is used to construct a multiphysics coupling model based on the dielectric constant reference value and the intrinsic characteristic parameters, and solve the multiphysics coupling model to obtain the temperature field distribution; The time-domain feature analysis module is used to extract time-domain features within a preset time period based on the measured voltage data, and to calculate the voltage ratio of the test capacitor device based on the time-domain features within the preset time period. The dielectric loss correction module is used to correct the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value. The lifetime prediction module is used to calculate the remaining lifetime of the test capacitor device based on the corrected dielectric loss value and the temperature field distribution.

[0049] As a preferred embodiment, calculating the dielectric constant reference value based on the structural parameters includes: The quantum capacitance reference value is calculated based on a preset microwave frequency and a preset quantum number; Calculate the volume of the medium between the electrodes based on the electrode area and the electrode spacing; The ratio of the quantum capacitance reference value to the volume of the dielectric medium between the plates is determined as the dielectric constant reference value.

[0050] As a preferred embodiment, the multiphysics coupling model is specifically as follows: In the formula, The curl of the magnetic field strength; The electrical conductivity of the material; Electric field strength; The effective dielectric constant; This is the reference value for the dielectric constant; The first-order dielectric polarizability; It is a third-order nonlinear polarization. The density of the material; Specific heat capacity of the material; The thermal conductivity of the material; t represents the temperature field distribution; t represents time.

[0051] As a preferred embodiment, the time-domain features within a preset time period are extracted based on the measured voltage data, and the voltage ratio of the test capacitor device is calculated based on the time-domain features within the preset time period, including: The voltage signal and sampling frequency at each time point are obtained from the measured voltage data; For each time point, the scaling factor is calculated based on the sampling frequency; Calculate the time-domain features based on the voltage signal and the scaling factor; Calculate the mean of the temporal features of the preset time period, and determine the maximum temporal feature of the preset time period; The ratio of the maximum time-domain feature to the mean of the time-domain features is determined as the voltage ratio.

[0052] As a preferred embodiment, the temporal characteristics within a preset time period are calculated using the following formula: In the formula, The temporal characteristics within a preset time period; Scale factor; for The voltage signal at a given moment; For wavelet complex conjugate; t represents the time axis coordinate of the voltage signal; t is time.

[0053] As a preferred embodiment, the measured dielectric loss value is corrected based on the voltage ratio to obtain the corrected dielectric loss value, including: Obtain the nonlinear coefficients of materials at several different aging reaction levels; Based on the nonlinear coefficients of each material, the voltage ratio, and the measured dielectric loss value, the corrected dielectric loss value is calculated: In the formula, This is the corrected value for dielectric loss. This is the measured value of the dielectric loss. The nonlinear coefficient of the nth-order material; The aging reaction order; This is the voltage ratio.

[0054] As a preferred embodiment, the remaining lifespan of the test capacitor device is calculated based on the corrected dielectric loss value and the temperature field distribution, including: The current rate of increase of the dielectric loss value is calculated based on the corrected dielectric loss value and the temperature field distribution. The remaining lifespan of the test capacitor device is calculated based on the preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate.

[0055] As a preferred embodiment, the current dielectric loss growth rate is calculated using the following formula: In the formula, This represents the current rate of increase in dielectric loss. The aging coefficient; The activation energy of the material; is the aging reaction rate constant.

[0056] As a preferred embodiment, the remaining lifespan of the test capacitor device is calculated based on a preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate, including: Using a preset dielectric loss threshold as the upper limit of integration and a corrected dielectric loss value as the lower limit of integration, the ratio between the increase in dielectric loss value and the growth rate of dielectric loss value is accumulated, and the accumulated result is determined as the remaining life of the test capacitor equipment.

[0057] Implementing the above embodiments has the following effects: This invention provides a device for predicting the remaining life of a capacitor device. The device acquires the structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the tested capacitor device. It calculates a reference value for the dielectric constant based on the structural parameters. A multiphysics coupling model is constructed based on the reference value and inherent characteristic parameters, and the model is solved to obtain the temperature field distribution. Time-domain features within the preset time period are extracted based on the measured voltage data, and the voltage ratio of the tested capacitor device is calculated based on these features. The measured dielectric loss value is corrected based on the voltage ratio to obtain a corrected dielectric loss value. Finally, the remaining life of the tested capacitor device is calculated based on the corrected dielectric loss value and the temperature field distribution. This invention obtains the structural parameters and inherent characteristic parameters of the test capacitor device, as well as the measured voltage data and measured dielectric loss value. Based on the structural parameters and inherent characteristic parameters, the temperature field distribution is calculated, and the time-domain characteristics that reflect voltage fluctuations are extracted from the measured voltage data. Then, the measured dielectric loss value is corrected based on the time-domain characteristics so that the corrected dielectric loss value adapts to the actual voltage conditions of the capacitor device. The remaining lifetime is predicted based on the temperature field distribution and the corrected dielectric loss value, taking into account environmental factors and voltage fluctuations, thereby improving the accuracy of the remaining lifetime prediction.

[0058] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A method for predicting the remaining life of a capacitor bank, characterized in that, include: The structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the test capacitor device are obtained; wherein, the structural parameters include plate area and plate spacing; the inherent characteristic parameters include electric field strength, material conductivity, material thermal conductivity, material density, material specific heat capacity, and material activation energy; Calculate the reference value of dielectric constant based on the structural parameters; A multiphysics coupling model is constructed based on the dielectric constant reference value and the intrinsic characteristic parameters, and the temperature field distribution is obtained by solving the multiphysics coupling model. Based on the measured voltage data, extract the time-domain features within a preset time period, and calculate the voltage ratio of the test capacitor device according to the time-domain features within the preset time period; Based on the voltage ratio, the measured dielectric loss value is corrected to obtain the corrected dielectric loss value; The remaining lifespan of the test capacitor device is calculated based on the corrected dielectric loss value and the temperature field distribution.

2. The method for predicting the remaining lifespan of capacitor equipment according to claim 1, characterized in that, The calculation of the dielectric constant reference value based on the structural parameters includes: The quantum capacitance reference value is calculated based on a preset microwave frequency and a preset quantum number; Calculate the volume of the medium between the electrodes based on the electrode area and the electrode spacing; The ratio of the quantum capacitance reference value to the volume of the dielectric medium between the plates is determined as the dielectric constant reference value.

3. The method for predicting the remaining lifespan of capacitor devices according to claim 2, characterized in that, The multiphysics coupling model is specifically as follows: In the formula, The curl of the magnetic field strength; The electrical conductivity of the material; Electric field strength; The effective dielectric constant; This is the reference value for the dielectric constant; The first-order dielectric polarizability; It is a third-order nonlinear polarization. The density of the material; Specific heat capacity of the material; The thermal conductivity of the material; t represents the temperature field distribution; t represents time.

4. The method for predicting the remaining lifespan of capacitor equipment according to claim 3, characterized in that, The step of extracting time-domain features within a preset time period based on the measured voltage data, and calculating the voltage ratio of the test capacitor device based on the time-domain features within the preset time period, includes: The voltage signal and sampling frequency at each time point are obtained from the measured voltage data; For each time point, the scaling factor is calculated based on the sampling frequency; Calculate the time-domain features based on the voltage signal and the scaling factor; Calculate the mean of the temporal features of the preset time period, and determine the maximum temporal feature of the preset time period; The ratio of the maximum time-domain feature to the mean of the time-domain features is determined as the voltage ratio.

5. The method for predicting the remaining life of capacitor equipment according to claim 4, characterized in that, The temporal characteristics within a preset time period are calculated using the following formula: In the formula, The temporal characteristics within a preset time period; Scale factor; for The voltage signal at a given moment; For wavelet complex conjugate; t represents the time axis coordinate of the voltage signal; t is time.

6. The method for predicting the remaining life of a capacitor bank according to claim 5, characterized in that, The step of correcting the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value includes: Obtain the nonlinear coefficients of materials at several different aging reaction levels; Based on the nonlinear coefficients of each material, the voltage ratio, and the measured dielectric loss value, the corrected dielectric loss value is calculated: In the formula, This is the corrected value for dielectric loss. This is the measured value of the dielectric loss. The nonlinear coefficient of the nth-order material; The aging reaction order; This is the voltage ratio.

7. The method for predicting the remaining life of capacitor equipment according to claim 6, characterized in that, The step of calculating the remaining lifespan of the test capacitor device based on the corrected dielectric loss value and the temperature field distribution includes: The current rate of increase of the dielectric loss value is calculated based on the corrected dielectric loss value and the temperature field distribution. The remaining lifespan of the test capacitor device is calculated based on the preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate.

8. The method for predicting the remaining lifespan of a capacitor bank according to claim 7, characterized in that, The current rate of increase in dielectric loss is calculated using the following formula: In the formula, This represents the current rate of increase in dielectric loss. The aging coefficient; The activation energy of the material; is the aging reaction rate constant.

9. The method for predicting the remaining life of a capacitor bank according to claim 8, characterized in that, The step of calculating the remaining lifespan of the test capacitor device based on a preset dielectric loss threshold, the corrected dielectric loss value, and the current dielectric loss growth rate includes: Using a preset dielectric loss threshold as the upper limit of integration and a corrected dielectric loss value as the lower limit of integration, the ratio between the increase in dielectric loss value and the growth rate of dielectric loss value is accumulated, and the accumulated result is determined as the remaining life of the test capacitor equipment.

10. A device for predicting the remaining life of a capacitor bank, characterized in that, include: The module includes a data acquisition module, a baseline value calculation module, a temperature field solution module, a time-domain characteristic analysis module, a dielectric loss value correction module, and a lifetime prediction module. The data acquisition module is used to acquire the structural parameters, inherent characteristic parameters, measured dielectric loss values, and measured voltage data within a preset time period of the test capacitor device; wherein, the structural parameters include plate area and plate spacing; the inherent characteristic parameters include electric field strength, material conductivity, material thermal conductivity, material density, material specific heat capacity, and material activation energy; The reference value calculation module is used to calculate the reference value of dielectric constant based on the structural parameters; The temperature field solving module is used to construct a multiphysics coupling model based on the dielectric constant reference value and the intrinsic characteristic parameters, and solve the multiphysics coupling model to obtain the temperature field distribution; The time-domain feature analysis module is used to extract time-domain features within a preset time period based on the measured voltage data, and to calculate the voltage ratio of the test capacitor device based on the time-domain features within the preset time period. The dielectric loss correction module is used to correct the measured dielectric loss value based on the voltage ratio to obtain the corrected dielectric loss value. The lifetime prediction module is used to calculate the remaining lifetime of the test capacitor device based on the corrected dielectric loss value and the temperature field distribution.

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