A simulation method and device for moisture aging electrical properties of zinc oxide varistor

Abstract

The application provides a simulation method and device for the moisture aging electrical performance of a zinc oxide varistor, comprising: establishing a grain boundary micro-topology structure of the zinc oxide varistor, the grain boundary micro-topology structure comprising a plurality of conductive grains and grain boundaries between adjacent grains; establishing corresponding equivalent branches for the grain boundaries, mapping the grain boundary micro-topology structure into an electrical network model composed of a plurality of conductive nodes and equivalent branches; determining physical parameters representing moisture degradation according to a moisture aging test of the zinc oxide varistor, and updating the electrical network model by adjusting the physical parameters while keeping the grain boundary micro-topology structure unchanged to obtain the voltage-current characteristic curve and micro-current distribution under the corresponding moisture state. The application realizes quantitative correlation between the moisture degradation state and the micro-grain boundary electrical characteristics, thereby realizing high-precision simulation of the voltage-current characteristic curve and micro-current distribution under the corresponding moisture state, and significantly improving the physical authenticity of the simulation results.

Description

Technical Field

[0001] This invention relates to the field of power electronic device simulation technology, and more specifically, to a simulation method and apparatus for the electrical performance of zinc oxide resistors under moisture aging. Background Technology

[0002] Moisture buildup inside surge arresters is a relatively frequent and potential defect. Due to a breach in the seal, moisture enters the arrester through respiration and adheres evenly to the sides of the zinc oxide varistors. On one hand, the adhering moisture creates additional conductive paths, increasing the leakage current of the arrester. On the other hand, the moisture adhering to the sides of the zinc oxide varistors can affect the internal structure of the varistors over time, leading to a decline in their electrical performance, resulting in increased leakage current and alterations to the volt-ampere characteristic curve.

[0003] The microstructure of zinc oxide resistors determines their nonlinear characteristics. During high-temperature sintering, grain boundary layers with double Schottky barriers are formed between zinc oxide grains. Therefore, zinc oxide resistors can be considered as a complex microscopic nonlinear electrical network with numerous grains as nodes and grain boundary layers as branches. Under an applied voltage, each grain follows Ohm's law. By solving the electrical network equations, the internal current and voltage distribution can be obtained, and thus macroscopic characteristics such as the volt-ampere curve can be derived. The essence of zinc oxide resistor degradation is the change in microstructure and properties under electrical stress, which leads to changes in macroscopic performance.

[0004] For simulation modeling of the microstructure of zinc oxide resistors, the lack of a quantitative description method for the correlation between moisture absorption and microstructural characteristics limits the application of the resistor microstructure simulation model in simulating the degradation process. It is urgent to establish the correlation between the microscopic characteristics of zinc oxide resistors under moisture conditions and the key parameters of the simulation model, ultimately achieving simulation calculations of zinc oxide resistors under moisture conditions at the microscopic level. Summary of the Invention

[0005] In view of this, the present invention proposes a simulation method for the electrical performance of zinc oxide resistors under moisture aging, aiming to solve the problem that existing microscopic simulation models lack quantitative correlation between the moisture degradation of zinc oxide resistors and their microstructural characteristics, making it difficult to accurately simulate the degradation of the volt-ampere characteristics and the microcurrent distribution of zinc oxide resistors under moisture conditions. In one aspect, this invention proposes a simulation method for the electrical performance of zinc oxide resistors under moisture aging, comprising: A grain boundary microtopology is established for a zinc oxide resistor, wherein the grain boundary microtopology comprises multiple conductive grains and grain boundaries located between adjacent grains; Establish corresponding equivalent branches for the grain boundary, and map the microscopic topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches; Based on the moisture aging test of zinc oxide resistors, physical parameters characterizing moisture degradation are determined. Under the condition of keeping the micro-topology of the grain boundaries unchanged, the electrical network model is updated by adjusting the physical parameters to obtain the current-voltage characteristic curve and micro-current distribution under the corresponding moisture state.

[0006] Furthermore, in the simulation method for the electrical performance of the zinc oxide resistor under moisture aging, the grain boundary micro-topology is generated by a Voronoi grid, where each Voronoi cell corresponds to a conductive grain, and the common edge between adjacent Voronoi cells corresponds to a grain boundary.

[0007] Furthermore, in the simulation method for the electrical performance of zinc oxide resistors under moisture aging described above, the equivalent branch includes effective grain boundary branches and ineffective grain boundary branches; wherein, The effective grain boundary branch is composed of a grain boundary nonlinear resistor and a grain boundary nonlinear capacitor connected in parallel; and the number of the effective grain boundary branch is determined by the effective grain boundary ratio in the physical parameters. The invalid grain boundary branch only includes the resistance of the thick grain boundary region.

[0008] Furthermore, in the simulation method for the electrical performance of zinc oxide resistor sheet under moisture aging, in the electrical network model, each conductive grain is characterized by a grain resistance, and the grain resistance is connected in series with the equivalent branch of the adjacent grain boundary.

[0009] Furthermore, in the simulation method for the electrical performance of zinc oxide resistor under moisture aging, the physical parameters include: effective grain boundary ratio and grain boundary barrier height; wherein, the grain boundary barrier height is used to characterize the current-voltage characteristics of the nonlinear resistance of the grain boundary; and the effective grain boundary ratio is used to represent the proportion of the number of grain boundaries with nonlinear characteristics to the total number of grain boundaries during the moisture aging process.

[0010] Furthermore, in the above simulation method for the electrical performance of zinc oxide resistors under moisture aging, the electrical network model is updated in any of the following ways: While keeping the grain boundary microstructure and grain boundary barrier height constant, the electrical performance changes under different moisture aging conditions are simulated by changing the effective grain boundary ratio. While keeping the grain boundary microtopology and effective grain boundary ratio unchanged, the changes in electrical performance under different moisture aging conditions are simulated by changing the grain boundary barrier height.

[0011] Furthermore, in the simulation method for the electrical performance of the zinc oxide resistor under moisture aging described above, the equivalent impedance between any two conductive grains... Z eq It can be represented as: Zeq =R GN +( R L / / R DB / / C IL )+ R GN in, R GN Grain resistance, R L For thick grain boundary region resistance, R DB For nonlinear resistance in the grain boundary region, C IL The nonlinear capacitor in the grain boundary region; the nonlinear resistor in the grain boundary region R DB and the nonlinear capacitance of the grain boundary region C IL The dynamic changes in the aging state of zinc oxide resistors due to moisture.

[0012] Furthermore, in the simulation method for the electrical performance of the zinc oxide resistor under moisture aging described above, the nonlinear resistance of the grain boundary region... R DB and the nonlinear capacitance of the grain boundary region C IL The value of varies depending on the effective grain boundary ratio and grain boundary barrier height in the physical parameters.

[0013] This invention provides a simulation method for the electrical performance of zinc oxide resistors under moisture aging. By establishing the grain boundary micro-topology of the zinc oxide resistor and creating corresponding equivalent branches for the grain boundaries to form an electrical network model, and then combining this with moisture aging tests to determine the physical parameters characterizing moisture degradation, the electrical network model is dynamically updated while keeping the grain boundary micro-topology unchanged. This achieves a quantitative correlation between the moisture degradation state and the electrical properties of the micro-grain boundaries, thereby enabling high-precision simulation of the current-voltage characteristic curve and micro-current distribution under the corresponding moisture state. Through this quantitative correlation mechanism, the problem of simulation results distortion caused by the lack of quantitative correlation between moisture degradation and micro-structural characteristics in existing micro-simulation models is effectively solved, significantly improving the physical authenticity of the simulation results.

[0014] On the other hand, the present invention also proposes a simulation device for the electrical performance of zinc oxide resistor sheet under moisture aging, comprising: a topology construction module for establishing the grain boundary micro-topology of zinc oxide resistor sheet, wherein the grain boundary micro-topology includes multiple conductive grains and grain boundaries located between adjacent grains; The electrical network model mapping module is used to establish corresponding equivalent branches for the grain boundary and map the micro-topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches. The parameter update module is used to determine the physical parameters characterizing moisture degradation based on the moisture aging test of the zinc oxide resistor sheet, and to update the electrical network model by adjusting the physical parameters while keeping the micro-topology of the grain boundary unchanged. The performance output module is used to output the volts under the corresponding moisture condition based on the updated electrical network model. Safety characteristic curves and micro current distribution.

[0015] Furthermore, in the simulation device for the electrical performance of zinc oxide resistors under moisture aging, the equivalent branch includes effective grain boundary branches and ineffective grain boundary branches based on grain boundaries; wherein, The effective grain boundary branches are composed of grain boundary nonlinear resistors and grain boundary nonlinear capacitors connected in parallel; and the number of effective grain boundary branches is determined by the effective grain boundary ratio in the physical parameters; the ineffective grain boundary branches only include thick grain boundary region resistors.

[0016] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the simulation method for the electrical performance of zinc oxide resistive sheet under moisture aging as described in any of the above claims.

[0017] The present invention provides a simulation method for the electrical performance of zinc oxide resistors under moisture aging. This method establishes a microscopic topology containing multiple conductive grains and grain boundaries between adjacent grains using a topology construction module. This topology is then transformed into an electrical network model using an electrical network model mapping module, enabling circuit characterization of the true microstructure of the zinc oxide resistor. Furthermore, a parameter update module updates the electrical network model based on physical parameters related to moisture aging while maintaining the grain boundary microscopic topology, establishing a quantitative correlation between the macroscopic moisture degradation state and the electrical properties of the microscopic grain boundaries. Finally, a performance output module directly outputs the current-voltage characteristic curve and microscopic current distribution under the corresponding moisture state. This achieves high-precision simulation of the electrical performance of zinc oxide resistors under moisture aging, effectively solving the problem of distorted simulation results caused by the lack of quantitative correlation between moisture degradation and microscopic structural characteristics in existing microscopic simulation models. This significantly improves the physical realism and engineering application value of the simulation results. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart of a simulation method for the electrical performance of zinc oxide resistors under moisture aging in an embodiment of the present invention; Figure 2 This is a schematic diagram of the distribution of generation points used to construct the microstructure of the grain boundaries of the zinc oxide resistor sheet in an embodiment of the present invention; Figure 3 Based on Figure 2 A schematic diagram of the Delaunay triangulation after the generated points are triangulated. Figure 4 Based on Figure 3 Voronoi diagram generated from Delaunay triangulation results; Figure 5 This is a comparison diagram of the Voronoi grid (non-uniformity 5) generated in the embodiment of the present invention and the microstructure of the actual ZnO resistor sheet; Figure 6 The equivalent circuit model diagram of the grain-grain boundary layer-grain structure in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiment of the present invention is shown. Figure 7 This is a current distribution cloud map simulating the electrical performance of the zinc oxide resistor during the moisture aging process in this embodiment of the invention. Figure 8 This is a schematic diagram of the electrical network model when the effective grain boundaries are 100% in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 9 This is a schematic diagram of the electrical network model when the effective grain boundaries are 90% in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 10 This is a schematic diagram of the electrical network model when the effective grain boundaries are 70% in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 11 This is a schematic diagram of the electrical network model when the effective grain boundaries are 50% in the simulation method for the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 12 This is a schematic diagram of the electrical network model when the effective grain boundaries are 30% in the simulation method for the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 13 This is a schematic diagram of the electrical network model when the effective grain boundaries are 10% in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention. Figure 14 The VI curves under different effective grain boundary ratios in the simulation method of the electrical performance of zinc oxide resistor sheet under moisture aging provided in the embodiments of the present invention; Figure 15This is a schematic diagram illustrating the change trend of the barrier height of the zinc oxide resistor under simulated damp conditions in an embodiment of the present invention. Figure 16 The VI characteristic curves corresponding to different barrier heights are provided for embodiments of the present invention. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] Method Implementation Examples: See Figure 1 The simulation method for the electrical performance of zinc oxide resistor under moisture aging according to an embodiment of the present invention includes: step S1, establishing the grain boundary micro-topological structure of the zinc oxide resistor, wherein the grain boundary micro-topological structure The structure contains multiple conductive grains and grain boundaries located between adjacent grains.

[0021] Specifically, the grain boundary microtopology is generated by a Voronoi grid, where each Voronoi cell corresponds to a conductive grain, and the common edge between adjacent Voronoi cells corresponds to a grain boundary.

[0022] It is generally believed that the morphology of the two-dimensional Voronoi grid is similar to the microstructure of zinc oxide resistors obtained by SEM imaging. By adjusting the non-uniformity of the Voronoi network, the two-dimensional simulation of the resistor microstructure can be achieved.

[0023] In this embodiment, to establish a simulation model that matches the actual microstructure of the zinc oxide resistor, a set of generation points (seed points) are randomly arranged on a two-dimensional plane, such as... Figure 2 As shown, each generated point represents the grain center location. A Voronoi diagram is constructed based on these generated points. Each Voronoi cell is a polygonal region composed of all electrical charges in space closest to the seed point, and this region corresponds to a conductive grain. Connecting each pair of adjacent points forms a series of boundary segments (common edges between adjacent Voronoi cells), dividing the entire plane into triangular sections, known as the Delaunay triangulation. Figure 3As shown. The Delaunay triangulation is the dual graph of the Voronoi diagram. Taking the circumcenter of the Delaunay triangle as the Voronoi vertex, and connecting the Voronoi vertices sequentially, we obtain the Voronoi diagram, as shown. Figure 4 As shown. Voronoi grid inhomogeneity is determined by randomly selecting the vertex positions of Delaunay triangles within a circle of radius d near the grid points.

[0024] The actual zinc oxide resistor sheet has irregular polygonal grain boundaries, while the Voronoi grid is uniformly arranged when no random variables are introduced. The regularity of the Voronoi grid can be adjusted by adjusting the non-uniformity. Based on the scanning electron microscope image of the actual zinc oxide resistor sheet, in this embodiment, the non-uniformity is set to 5 to simulate the non-uniform characteristics of the actual microstructure, such as... Figure 5 As shown.

[0025] Step S2: Establish corresponding equivalent branches for the grain boundary, and map the microscopic topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches.

[0026] Combination Figure 6 Specifically, the equivalent branch includes effective grain boundary branches and ineffective grain boundary branches; wherein, the effective grain boundary branches are composed of grain boundary nonlinear resistors and grain boundary nonlinear capacitors connected in parallel; and the number of effective grain boundary branches is determined by the effective grain boundary ratio in the physical parameters; the ineffective grain boundary branches only include thick grain boundary region resistors.

[0027] Furthermore, in the electrical network model, each conductive grain is characterized by a grain resistance, which is connected in series with the equivalent branch of the adjacent grain boundary.

[0028] In this embodiment, the equivalent branches in the electrical network model are divided into two categories based on the electrical state of grain boundaries during the moisture aging process: effective grain boundary branches and ineffective grain boundary branches. Effective grain boundary branches are used to simulate grain boundaries that maintain a complete Schottky barrier structure, and their electrical performance exhibits nonlinear current-voltage characteristics. This branch is the nonlinear resistance of the grain boundary. R DB and grain boundary nonlinear capacitance C IL It is composed of parallel connections.

[0029] Ineffective grain boundary branches are used to simulate grain boundaries where the barrier height decreases due to moisture intrusion. Calcium grain boundaries lose their nonlinear characteristics and are simplified in the model as a thick grain boundary region resistance. R L .

[0030] In specific implementation, the equivalent impedance between any two of the conductive grains Z eq It can be represented as: Z eq =R GN +( R L / / R DB / / C IL )+ R GN in, R GN Grain resistance, R L For thick grain boundary region resistance, R DB For nonlinear resistance in the grain boundary region, C IL The nonlinear capacitor in the grain boundary region; the nonlinear resistor in the grain boundary region R DB and the nonlinear capacitance of the grain boundary region C IL The dynamic changes in the aging state of zinc oxide resistors due to moisture.

[0031] The nonlinear resistance of the grain boundary region R DB and the nonlinear capacitance of the grain boundary region C IL The value of varies depending on the effective grain boundary ratio and grain boundary barrier height among the physical parameters. Both can be calculated using common models for grain boundary calculations, such as: Nonlinear resistive grain boundaries R DB The calculation is as follows: Under the action of an applied voltage V, the directional movement of charge fills the surface states of the grain boundary layer, thus increasing the potential barrier height. φ b (V) The change caused the current flowing through the grain boundary layer. I The change is shown in the following formula: In the formula, This represents the grain boundary area; Richardson's constant, which reflects the current-voltage characteristics in a Schottky barrier, is used. For temperature; Boltzmann's constant; This represents the Fermi level of the ZnO grain relative to the conduction band. This represents the charge of electrons. It can also be expressed as the interface current density. Therefore, the surface resistance of grain boundaries It can be represented as: R DB = *L, where L is the boundary length (the length of the boundary between the two grain contact surfaces).

[0032] Among them, the barrier height φ b With applied voltage V Change with change: In the formula, The critical voltage is the voltage at which the applied voltage increases to exceed a certain threshold. Then, the barrier disappeared. Reflects the interfacial charge Impact on barrier height: In the formula, The relative permittivity of the material; It is the vacuum relative permittivity; For electron charge; Donor density. Interfacial charge. This represents the number of electrons trapped in the grain boundary interface states, with the trapped electrons originating from the valence band apex of the grain boundary. Quasi-Fermi level filled to the grain boundary Based on the double Schottky barrier model, the charge at grain boundaries in non-equilibrium states... It can be represented as: In the formula, For the interface state density, It is the quasi-Fermi level of the grain boundary. It follows the Fermi-Dirac distribution: In the formula, For the quasi-Fermi level, when an external voltage is applied... V When >0, the quasi-Fermi level At the Fermi level Offset occurs based on: interface state density Three forms can be adopted: impulse distribution, Gaussian distribution, and rectangular distribution, among which the most common is... Centered on, Let Variance be and total density be . The specific form can be selected based on the properties of the zinc oxide resistor and experimental data to improve simulation accuracy.

[0033] The applied voltage can be calculated through iteration. V Barrier height of grain boundaries under action φ b This allows us to obtain the current passing through the grain boundaries. I Thus, the nonlinear resistance of grain boundaries is obtained.

[0034] Grain boundary nonlinear capacitance The calculation is as follows: The grain boundary capacitance can be calculated from the barrier height and the applied voltage: In the formula, φ b For the height of the barrier, The relative permittivity of the material; It is the vacuum relative permittivity; For electron charge; Donor density, V This refers to the applied voltage.

[0035] Based on the above model, the current distribution within half a cycle in the microstructure of the zinc oxide resistor sheet under an applied AC voltage of a preset frequency can be calculated, such as... Figure 7 As shown (e.g., when the AC voltage frequency is 50Hz): due to the nonlinear characteristics of some grain boundaries, as the voltage gradually increases, the resistivity of the nonlinear grain boundary decreases, and the current has a larger value along the path of the nonlinear grain boundary, which manifests as a channel effect.

[0036] Step S3: Based on the moisture aging test of the zinc oxide resistor, determine the physical parameters characterizing moisture degradation. Under the condition of keeping the micro-topology of the grain boundary unchanged, update the electrical network model by adjusting the physical parameters to obtain the current-voltage characteristic curve and micro-current distribution under the corresponding moisture state.

[0037] Specifically, the physical parameters include: effective grain boundary ratio and grain boundary barrier height; wherein, the grain boundary barrier height is used to characterize the current-voltage characteristics of the nonlinear resistance of the grain boundary; and the effective grain boundary ratio is used to represent the proportion of grain boundaries with nonlinear characteristics to the total number of grain boundaries during the moisture aging process.

[0038] In this embodiment, the electrical network model is updated in any of the following ways: While keeping the grain boundary microstructure and grain boundary barrier height constant, the electrical performance changes under different moisture aging conditions are simulated by changing the effective grain boundary ratio. While keeping the grain boundary microtopology and effective grain boundary ratio unchanged, the changes in electrical performance under different moisture aging conditions are simulated by changing the grain boundary barrier height.

[0039] After updating the model parameters, a constant DC voltage is applied to the entire electrical network model. Conventional circuit solving methods (such as the built-in solver in the simulation software) are used to calculate the node voltages and branch currents. By correlating the total current with the applied voltage, the current-voltage characteristic curve of the zinc oxide resistor can be obtained. At the same time, based on the magnitude of each branch current and its distribution in the grain boundary micro-topology, a micro-current distribution map can be generated to identify local high current density regions caused by moisture aging.

[0040] When zinc oxide resistors are exposed to moisture, the internal pores and other structural features can affect grain boundary conductivity due to moisture intrusion. In the simulation model, while keeping the model size and barrier height constant, the proportion of effective grain boundaries to the total number of grain boundaries is varied. Grain boundaries with nonlinear current-voltage characteristics are selected through random sampling. In this embodiment, Figure 13 The current-voltage characteristic curves of zinc oxide resistive films with different effective grain boundary ratios are shown. Each curve corresponds to a specific effective grain boundary ratio value (e.g., ...). Figure 8-13 (Corresponding effective grain boundary ratio value). By comparison Figure 14 As can be seen from the curves, as the effective grain boundary ratio decreases, the VI curve generally shifts to the upper left as the effective grain boundary ratio decreases from 100% to 70%. With further reductions in the ratio, the inflection point shifts significantly to the right, and the overall nonlinear characteristics deteriorate. When the effective grain boundary ratio decreases to 10%, the nonlinear resistance characteristics are essentially lost.

[0041] Simulated moisture absorption test results show that the barrier height of the zinc oxide resistor sheet decreases when damp, and the greater the degree of moisture absorption, the greater the decrease in barrier height. Based on this result, the model size and effective grain boundary ratio are kept constant in the simulation model, while the barrier height is varied. Specifically, in this embodiment, different types of zinc oxide resistor sheet samples (e.g., those without side glaze, organic glaze, and glass glaze) are immersed in water with different conductivity to simulate their aging behavior under various moisture conditions, and the corresponding grain boundary barrier height variation trend with immersion time is obtained, such as... Figure 15 As shown. Furthermore, Figure 15 Using the potential barrier height corresponding to different aging stages as input parameters, we substitute them into the electrical network model to simulate the current-voltage characteristics, and obtain the following results: Figure 16The current-voltage characteristic curves shown at different barrier heights reveal two trends in the VI curve as the barrier height decreases. First, the VI curve shifts to the right overall, specifically manifested as an increase in leakage current at the same voltage, meaning the impedance decreases. Second, the nonlinear resistance characteristic weakens until it is essentially lost, i.e., the inflection point of the curve shifts to the right, causing the curve to gradually change from a "Γ-shaped" to an "I-shaped" curve. When the barrier height decreases to 25%, the nonlinear resistance characteristic is essentially lost.

[0042] It is evident from the above that the simulation method for the electrical performance of zinc oxide resistors under moisture aging provided in this embodiment establishes the microscopic topology of the grain boundaries of the zinc oxide resistors, creates corresponding equivalent branches for the grain boundaries to form an electrical network model, and then combines moisture aging tests to determine the physical parameters characterizing moisture degradation. Under the condition of keeping the microscopic topology of the grain boundaries unchanged, the electrical network model is dynamically updated, realizing a quantitative correlation between the moisture degradation state and the electrical properties of the microscopic grain boundaries. This enables high-precision simulation of the current-voltage characteristic curve and microscopic current distribution under the corresponding moisture state. Through this quantitative correlation mechanism, the problem of simulation results distortion caused by the lack of quantitative correlation between moisture degradation and microscopic structural characteristics in existing microscopic simulation models is effectively solved, significantly improving the physical authenticity of the simulation results.

[0043] Device Example: The present invention also provides a simulation device for the electrical performance of zinc oxide resistors under moisture aging, for performing the above-described simulation method, the simulation device comprising: A topology building module is used to establish the grain boundary microtopology of the zinc oxide resistor sheet, wherein the grain boundary microtopology includes multiple conductive grains and grain boundaries located between adjacent grains. The electrical network model mapping module is used to establish corresponding equivalent branches for the grain boundary and map the micro-topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches. The parameter update module is used to determine the physical parameters characterizing moisture degradation based on the moisture aging test of the zinc oxide resistor sheet, and to update the electrical network model by adjusting the physical parameters while keeping the micro-topology of the grain boundary unchanged. The performance output module is used to output the current-voltage characteristic curve and microcurrent distribution under the corresponding moisture condition based on the updated electrical network model, so as to characterize the degree of moisture aging of the zinc oxide resistor.

[0044] The functions of each module correspond to the response steps in the simulation method described above. For details, please refer to the relevant descriptions in the method embodiments, which will not be repeated here.

[0045] The present invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the simulation method for the electrical performance of zinc oxide resistive elements under moisture aging as described in any of the preceding embodiments. The simulation device in this embodiment can be implemented by a computer executing the corresponding computer program.

[0046] In summary, the simulation device for the electrical performance of zinc oxide resistors under moisture aging provided by this invention establishes a microscopic topological structure containing multiple conductive grains and grain boundaries between adjacent grains through a topology construction module, and transforms it into an electrical network model through an electrical network model mapping module, thereby achieving circuit characterization of the true microstructure of the zinc oxide resistor. Furthermore, the parameter update module updates the electrical network model based on the physical parameters related to moisture aging while keeping the grain boundary microscopic topological structure unchanged, establishing a quantitative correlation between the macroscopic moisture degradation state and the microscopic grain boundary electrical properties. Finally, the performance output module directly outputs the current-voltage characteristic curve and microscopic current distribution under the corresponding moisture state, achieving high-precision simulation of the electrical performance of zinc oxide resistors under moisture aging. This effectively solves the problem of existing microscopic simulation models lacking a quantitative correlation between moisture degradation and microscopic structural characteristics, leading to distorted simulation results, and significantly improves the physical authenticity and engineering application value of the simulation results.

[0047] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A simulation method for the electrical performance of zinc oxide resistors under moisture aging, characterized in that, include: A grain boundary microtopology is established for a zinc oxide resistor, wherein the grain boundary microtopology comprises multiple conductive grains and grain boundaries located between adjacent grains; Establish corresponding equivalent branches for the grain boundary, and map the microscopic topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches; Based on the moisture aging test of zinc oxide resistors, physical parameters characterizing moisture degradation are determined. Under the condition of keeping the micro-topology of the grain boundaries unchanged, the electrical network model is updated by adjusting the physical parameters to obtain the current-voltage characteristic curve and micro-current distribution under the corresponding moisture state.

2. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 1, characterized in that, The grain boundary microstructure is generated by a Voronoi grid, where each Voronoi cell corresponds to a conductive grain, and the common edge between adjacent Voronoi cells corresponds to a grain boundary.

3. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 1, characterized in that, The equivalent branches include effective grain boundary branches and ineffective grain boundary branches; wherein... The effective grain boundary branch is composed of a grain boundary nonlinear resistor and a grain boundary nonlinear capacitor connected in parallel; and the number of the effective grain boundary branch is determined by the effective grain boundary ratio in the physical parameters. The invalid grain boundary branch only includes the resistance of the thick grain boundary region.

4. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 2, characterized in that, In the electrical network model, each conductive grain is characterized by a grain resistance, which is connected in series with the equivalent branch of the adjacent grain boundary.

5. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 1, characterized in that, The physical parameters include: effective grain boundary ratio and grain boundary barrier height; wherein, the grain boundary barrier height is used to characterize the current-voltage characteristics of the nonlinear resistance of the grain boundary; and the effective grain boundary ratio is used to represent the proportion of grain boundaries with nonlinear characteristics to the total number of grain boundaries during the moisture aging process.

6. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 5, characterized in that, Update the electrical network model using any of the following methods: While keeping the grain boundary microstructure and grain boundary barrier height constant, the electrical performance changes under different moisture aging conditions are simulated by changing the effective grain boundary ratio. While keeping the grain boundary microtopology and effective grain boundary ratio unchanged, the changes in electrical performance under different moisture aging conditions are simulated by changing the grain boundary barrier height.

7. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 1, characterized in that, Equivalent impedance between any two of the conductive grains Z eq It can be represented as: Z eq =R GN +（ R L / / R DB / / C IL ）+ R GN in, R GN Grain resistance, R L For thick grain boundary region resistance, R DB For nonlinear resistance in the grain boundary region, C IL The nonlinear capacitor in the grain boundary region; the nonlinear resistor in the grain boundary region R DB and the nonlinear capacitance of the grain boundary region C IL The dynamic changes in the aging state of zinc oxide resistors due to moisture.

8. The simulation method for the electrical performance of zinc oxide resistors under moisture aging according to claim 7, characterized in that, The nonlinear resistance of the grain boundary region R DB and the nonlinear capacitance of the grain boundary region C IL The value of varies depending on the effective grain boundary ratio and grain boundary barrier height in the physical parameters.

9. A simulation device for the electrical performance of zinc oxide resistors under moisture aging, characterized in that, include: A topology building module is used to establish the grain boundary microtopology of the zinc oxide resistor sheet, wherein the grain boundary microtopology includes multiple conductive grains and grain boundaries located between adjacent grains. The electrical network model mapping module is used to establish corresponding equivalent branches for the grain boundary and map the micro-topology of the grain boundary into an electrical network model composed of multiple conductive nodes and equivalent branches. The parameter update module is used to determine the physical parameters characterizing moisture degradation based on the moisture aging test of the zinc oxide resistor sheet, and to update the electrical network model by adjusting the physical parameters while keeping the micro-topology of the grain boundary unchanged. The performance output module is used to output the volts under the corresponding moisture condition based on the updated electrical network model. Safety characteristic curves and micro current distribution.

10. A computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement a simulation method for the electrical performance of a zinc oxide resistor element under moisture aging as described in any one of claims 1 to 9.

Images