Current transformer electromagnetic compatibility test optimization method and device and computer program product

Abstract

The invention discloses a current transformer electromagnetic compatibility test optimization method and device and a computer program product, and the method comprises the steps: carrying out a test in a pre-constructed lightning stroke simulation scene, and collecting simulation test data; the current offset degree is calculated based on the time sequence and the sliding window analysis technology, the dynamic response type of the mutual inductor is identified, and a peak report containing the immunity is generated; synchronously adjusting the initial average thickness and the nearest point distance of the metal shielding layer by using a full-factor design method, constructing a two-dimensional parameter matrix, and repeating the lightning stroke simulation test; and comparing each group of parameter test results with a shielding-layer-free reference result to calculate an interference suppression ratio, screening an optimal parameter combination by adopting a multi-objective optimization algorithm, and outputting a test report. According to the method, the coupling rule of shielding geometric layout and electromagnetic interference is quantified, the technical spanning from qualitative protection to quantitative optimization is realized, the test accuracy and the engineering applicability of an optimization scheme are improved, and the operation requirements of a smart grid on the current transformer are met.

Description

Technical Field

[0001] This invention relates to the field of electrical performance testing technology, specifically to an optimized method, apparatus, and computer program for electromagnetic compatibility testing of current transformers. Background Technology

[0002] In the development of the smart grid industry, current transformers, as core equipment for power system energy metering, relay protection, and condition monitoring, directly determine the stability and reliability of power grid operation through their electromagnetic compatibility (EMC). Lightning impulse interference resistance is a core aspect of current transformer EMC testing and optimization. Lightning impulses in natural scenarios generate strong electromagnetic interference, affecting the metering accuracy and protection reliability of the transformers. In severe cases, it can damage the transformers themselves and cause power grid safety accidents.

[0003] The electromagnetic compatibility performance of current transformers under lightning impulses is mainly affected by factors such as the amplitude of the lightning current, the spatial distance between the lightning and the transformer, and the structural parameters of the metal shielding layer. By analyzing the electromagnetic response of the transformer under lightning impulses and implementing targeted measures, the impact of interference can be mitigated. Therefore, the testing and evaluation of transformers under lightning simulation scenarios, and the optimization of the metal shielding layer based on the evaluation results, are crucial.

[0004] The prior art discloses a calibration method for an electromagnetic compatibility testing system. It determines the LISN impedance and output voltage VL based on the test input frequency, determines the input correction factor CSG_LISN by combining the test standard and voltage division relationship, and finally calculates the nominal output voltage VP of the signal generator. This method can quickly and accurately ensure that the LISN input reaches the expected level, providing calibration support for electromagnetic compatibility testing.

[0005] However, existing technologies still have significant shortcomings in testing and optimizing the electromagnetic compatibility of current transformers for lightning strikes: First, the testing dimension is limited, relying heavily on static peak current detection, which fails to capture the performance degradation pattern of the transformer during lightning strikes, resulting in incomplete anti-interference assessment. Second, the shielding optimization adopts a single-variable trial-and-error method, without constructing a comprehensive experimental system for shielding thickness and distance, making it impossible to quantify the relationship between shielding effectiveness and cost. Third, there is a lack of intelligent decision-making mechanisms; shielding schemes rely on human experience and are not comprehensively weighed through multi-objective optimization algorithms, leading to protection measures that are prone to lag or excessive redundancy, making it difficult to meet the needs of smart grids.

[0006] In summary, existing technologies cannot solve the problems of incomplete EMC testing and inaccurate shielding optimization for current transformers due to lightning impulses. There is an urgent need for a scientific and systematic testing and optimization scheme to make up for the shortcomings of existing technologies. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a method, device and computer program product for optimizing electromagnetic compatibility testing of current transformers, so as to improve the resistance of current transformers to lightning interference and ensure the stable operation of smart grids.

[0008] To address the aforementioned technical problems, this invention provides an optimization method for electromagnetic compatibility testing of current transformers, comprising: Step S1: Conduct a lightning strike simulation test in a pre-constructed lightning strike simulation scenario, and collect the simulated lightning distance, input lightning current amplitude, output current fluctuation value of the current transformer under test, and output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning strike to the recovery of the output current to a stable state. Step S2: Based on the collected test data, the current offset is calculated using time series analysis and sliding window analysis techniques. The dynamic response type of the current transformer under test is identified according to the changing characteristics of the current offset, and a peak report including the immunity is generated. Step S3: Collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, adjust the average thickness and nearest point distance synchronously according to the preset fixed step size to form a two-dimensional parameter matrix. Repeat the lightning strike simulation test of step S1 for each set of parameter combinations to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. Step S4: Compare the test results of each parameter combination with the benchmark test results without shielding layer, calculate the interference suppression rate, use a multi-objective optimization algorithm to optimize with the goal of maximizing shielding effect and minimizing cost, select the optimal parameter combination and output the test report.

[0009] Preferably, in step S1, the pre-constructed lightning strike simulation scenario is constructed in the following manner: Designate an isolation zone to isolate external electromagnetic noise; Multiple gradient points are evenly spaced within a preset gradient range to simulate the distance between a lightning strike and the current transformer under test. satisfy ,in, The maximum length of the experimental scenario. The equal spacing length of the gradient points; and the lightning strike simulation test is repeated, with each repetition covering all gradient points to eliminate random errors.

[0010] Preferably, in step S2, the current offset is calculated using the following formula:

[0011] in, For current offset, For the first The output current fluctuation value in each calculation cycle The periodic sequence calculated for current offset. To input the amplitude of the lightning current, The number of times the current offset was sampled. For the first Output current fluctuation time in each calculation cycle To simulate lightning distance; the dynamic response types include fast response type and continuous oscillation type.

[0012] Preferably, in step S2, the data in the peak report containing immunity includes: maximum current offset and occurrence timestamp, sum of output current floating time for each cycle, current recovery rate, and dynamic response type distribution statistics.

[0013] Preferably, in step S3, the specific process of synchronously adjusting the average thickness and the nearest point distance according to a preset fixed step size is as follows: first, fix the average thickness of the metal shielding layer to a certain value, traverse all nearest point distance values ​​at fixed intervals to complete the test, then adjust the average thickness and repeat the above nearest point distance value traversal process, finally generating... Group parameter combinations, where The number of times the average thickness is adjusted to a fixed difference; This represents the number of times the nearest point distance value is traversed; and the corresponding output current fluctuation value in the scenario is... The output current float time is ,in, This represents the average thickness of the metal shielding layer at various points. This is the distance from the metal shielding layer to the nearest point of the current transformer under test. This is the constant representing the fluctuation rate of the output current during lightning impulse. The output current floating time ratio constant of lightning impulse is denoted as .

[0014] Preferably, in step S4, the multi-objective optimization algorithm is a non-dominated sorting genetic algorithm, which uses a two-dimensional parameter space consisting of the average thickness of the shielding layer and the minimum installation distance of the interference source as the search domain to traverse the parameter space and select the optimal parameter combination from the found optimal solution set.

[0015] Preferably, in step S4, the test report includes a peak comparison table, interference suppression rate, and recommended optimal parameter combination scheme. The output format of the test report includes visual charts and textual conclusions. The visual charts include displays... and and The text presents a line graph showing the negative correlation trend and a heatmap showing the cost-interference suppression rate trade-off. The conclusions include shielding layer engineering parameters and the expected improvement in electromagnetic compatibility level.

[0016] The present invention also provides an electromagnetic compatibility testing optimization device for current transformers, comprising: The data simulation acquisition module is used to conduct lightning strike simulation tests in a pre-constructed lightning strike simulation scenario, and to acquire the simulated lightning distance, the input lightning current amplitude, the output current fluctuation value of the current transformer under test, and the output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning impact to the recovery of the output current to a stable state. The immunity peak analysis module is used to calculate the current deviation based on the collected test data using time series analysis and sliding window analysis techniques. It identifies the dynamic response type of the current transformer under test based on the changing characteristics of the current deviation and generates a peak report containing immunity. The shielding effectiveness optimization module is used to collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, the average thickness and nearest point distance are synchronously adjusted according to a preset fixed step size to form a two-dimensional parameter matrix. For each set of parameter combinations, the lightning strike simulation test in step S1 is repeated to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. The decision output configuration module is used to compare the test results of each parameter combination with the benchmark test results without a shielding layer, calculate the interference suppression rate, and use a multi-objective optimization algorithm to optimize with the goal of maximizing the shielding effect and minimizing the cost, select the optimal parameter combination and output a test report.

[0017] The present invention also provides an electromagnetic compatibility testing optimization device for current transformers, comprising: One or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more applications are configured to execute the current transformer electromagnetic compatibility test optimization method.

[0018] The present invention also provides a computer program product, including computer instructions, which instruct a computer device to perform operations corresponding to the current transformer electromagnetic compatibility test optimization method.

[0019] The beneficial effects of this invention are as follows: This invention effectively solves the technical shortcomings of existing current transformer lightning impulse electromagnetic compatibility testing, which suffers from a single dimension, reliance on manual experience for shielding optimization, and difficulty in balancing performance and cost. By combining lightning impulse speed simulation with time series and sliding window analysis techniques, it accurately captures the fluctuation time while collecting the output current fluctuation value to quantitatively evaluate the transient response characteristics of the equipment during lightning strikes. Furthermore, it employs a full-factor design method to adjust the average thickness and installation distance of the metal shielding layer and construct a two-dimensional parameter matrix, systematically quantifying the coupling law between shielding geometry and electromagnetic interference, completely eliminating the one-sidedness of traditional single-variable testing. Simultaneously, this invention incorporates interference suppression rate, dynamic response time, shielding volume, and cost into a multi-objective optimization system, replacing the traditional experience-based parameter tuning mode with a data-driven approach. This scientifically balances the performance requirements of current transformers against lightning interference with engineering economic benefits, and can output directly applicable recommended engineering parameters for the shielding layer. This represents a technological leap from qualitative protection to quantitative optimization, significantly improving the accuracy of current transformer electromagnetic compatibility testing and the engineering applicability of shielding optimization schemes, making the optimized current transformer's lightning impulse interference resistance more aligned with the actual operational needs of smart grids. Attached Figure Description

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

[0021] Figure 1 This is a flowchart illustrating an optimization method for electromagnetic compatibility testing of a current transformer according to Embodiment 1 of the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of an electromagnetic compatibility testing and optimization device for a current transformer according to Embodiment 2 of the present invention. Detailed Implementation

[0023] The following description of the embodiments is taken with reference to the accompanying drawings, which illustrate specific embodiments in which the invention can be implemented.

[0024] Please refer to Figure 1 As shown, this embodiment of the invention provides an optimization method for electromagnetic compatibility testing of current transformers, including: Step S1: Conduct a lightning strike simulation test in a pre-constructed lightning strike simulation scenario, and collect the simulated lightning distance, input lightning current amplitude, output current fluctuation value of the current transformer under test, and output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning strike to the recovery of the output current to a stable state. Step S2: Based on the collected test data, the current offset is calculated using time series analysis and sliding window analysis techniques. The dynamic response type of the current transformer under test is identified according to the changing characteristics of the current offset, and a peak report including the immunity is generated. Step S3: Collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, adjust the average thickness and nearest point distance synchronously according to the preset fixed step size to form a two-dimensional parameter matrix. Repeat the lightning strike simulation test of step S1 for each set of parameter combinations to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. Step S4: Compare the test results of each parameter combination with the benchmark test results without shielding layer, calculate the interference suppression rate, use a multi-objective optimization algorithm to optimize with the goal of maximizing shielding effect and minimizing cost, select the optimal parameter combination and output the test report.

[0025] Specifically, in this embodiment of the invention, step S1 involves pre-constructing a lightning strike simulation scenario to collect test data, and the process is as follows: First, an isolation zone with an area of ​​M = 10m² is defined to isolate external electromagnetic noise in order to simulate a lightning strike environment.

[0026] Then, the basic gradient range is defined. Within the preset gradient range, multiple gradient points are divided at equal intervals within the basic gradient range. The maximum length of the experimental scenario is used as the boundary, and the value range is a reasonable interval. This ensures that each point is used to characterize the mechanism of lightning electromagnetic coupling at different attenuation stages, thereby establishing a typical and repeatable lightning strike simulation scenario within the gradient range at a specified distance of meters from the current transformer under test.

[0027] Specifically, let the length of the equal interval be... Each gradient point is controlled to characterize the electromagnetic coupling mechanism at different decay stages, while the maximum length of the experimental scene is collected. Simulated lightning strike distance between the current transformers under test Due to the limitation of the maximum length of the experimental scenario, The range of values ​​for is: .

[0028] Next, a lightning strike simulation test was conducted. During the test, a number of key data points were comprehensively collected, including: the simulated lightning distance (corresponding to the gradient point location), the input lightning current amplitude (covering the typical lightning amplitude range), the output current fluctuation value of the current transformer under test (DUT), and the output current fluctuation time of the DUT. The current fluctuation time is the total duration from the initial moment of the lightning strike to the recovery of the output current to stability. Transient processes were accurately captured to evaluate dynamic characteristics. To ensure data reliability, the entire test process was repeated multiple times, with each repetition covering all gradient points to eliminate random errors and improve the statistical significance of the experimental results.

[0029] Step S2 performs peak immunity analysis. In each simulated lightning impulse test, the current deviation derived by the current transformer under test is calculated. This process is achieved by introducing a time series analysis method. Specifically, the period interval for calculating the output current fluctuation value of the current transformer under test is as follows: t The current offset is measured in seconds, and a sliding window analysis technique is used to track the trend of current offset changes in order to accurately identify the dynamic response characteristics of the current transformer under test.

[0030] Based on the sudden rise and fall behavior of the offset within the window, if it quickly falls to within 5% of the initial value, it is judged as a fast response type; if it continuously exceeds the preset current offset threshold and the fluctuation time is long, it is classified as a continuous oscillation type. Finally, a detailed peak report is generated, which includes the maximum current offset and occurrence timestamp, the sum of the output current fluctuation time of each cycle, the recovery rate, and key data of the response type distribution, which are used to comprehensively evaluate the device's immunity performance.

[0031] The current offset is calculated using the following formula:

[0032] in, Current offset represents the degree of deviation of the current transformer over a period of time after each test. For the first The output current fluctuation value in each calculation cycle is a fixed value, where the duration of each calculation cycle remains constant. ; The periodic sequence used for current offset calculation has values ​​set manually, as shown in this embodiment. The value range is 0.1 to 0.2 seconds; The input is the amplitude of the lightning current, which, as the intensity of the simulated lightning strike, directly determines the final current deviation result. The current offset is measured multiple times, and the current offset result is calculated from the data collected in each measurement. For the first The output current fluctuates within each calculation cycle, therefore it must satisfy: ; To simulate lightning distance, The larger the value of , the smaller the current deviation result. Therefore, the simulated lightning distance is inversely proportional to the current deviation.

[0033] A time-series data chain is generated by calculating the current offset. The sliding window analysis method is used to track the trend of current offset changes and identify two types of dynamic response characteristics. The two types of dynamic response characteristics are as follows: If the current offset suddenly rises to its peak value within the window, the output current fluctuation time will be twice the current offset acquisition period, i.e. If the decay rate drops to within 5% of the initial value, it is marked as a fast-response type; If the current offset continuously exceeds the preset current offset threshold, and the fluctuation duration is greater than... If the current is continuously oscillating, it is determined to be of the oscillating type. Furthermore, the sum of the output current fluctuation times in each current offset acquisition cycle is less than the period interval for calculating the output current fluctuation value of the current transformer under test, i.e.: .

[0034] The peak report, as a key output document of electromagnetic compatibility testing, comprehensively integrates the experimental analysis results and includes four core data items: maximum current offset and occurrence timestamp, total output current fluctuation time in each current offset acquisition cycle, recovery rate, and response type distribution statistics.

[0035] Specifically, the maximum current offset represents the highest value of the current offset, used to accurately assess the equipment's resistance to extreme lightning strikes; the sum of the output current float time in each current offset acquisition cycle, by accumulating the float time data in all cycles, is used to quantify the degree of sustained impact of lightning strikes on the current transformer under test; the recovery rate describes the rate at which the equipment's output current recovers from the interference state to a stable level, used to objectively obtain the efficiency performance of the equipment's autonomous recovery from electromagnetic interference; the response type distribution statistics, based on the classification results of dynamic modes, include fast response type and continuous oscillation type, used to deeply analyze the proportional distribution of the two dynamic response modes, thereby revealing the overall dynamic characteristic trend of the equipment.

[0036] Step S3 optimizes shielding effectiveness. Before electromagnetic compatibility testing, the system performs an initial data acquisition step, specifically acquiring initial data of the metal shielding layer around the current transformer under test. The initial data of the metal shielding layer includes the average thickness of the metal shielding layer at various points, which serves as a reference value for subsequent adjustments, and the distance from the metal shielding layer to the nearest point of the current transformer under test, which also serves as a key reference parameter.

[0037] Then, based on the preset parameter adjustment range, a fixed difference is set for multiple tests, specifically a fixed step size. In subsequent experiments, the thickness and nearest-point distance values ​​are changed synchronously with the fixed difference value. A two-dimensional parameter matrix is ​​formed using a full factorial design method, and lightning simulation tests are repeated. This test needs to be repeated to eliminate randomness. Operationally, the parameters are adjusted step by step, and the experimental process is repeated. The specific process includes: first, fixing the average thickness to a certain value, and then traversing all nearest-point distance values ​​at fixed intervals for testing; after completing the thickness layer, the average thickness is adjusted again with the fixed difference value, and the traversal process of distance values ​​is repeated for the next thickness value, ultimately generating multiple sets of parameter combinations.

[0038] Finally, the fluctuation value of the output current of the current transformer under test under different initial data scenarios of different metal shielding layers is calculated to reflect the response amplitude under electromagnetic interference, and the fluctuation time of the output current of the current transformer under test is used to characterize the duration of interference effect, so as to evaluate the optimization effect of shielding effectiveness. Under different initial data scenarios for different metal shielding layers, based on the results of the initial test, the average thickness of the metal shielding layer at various points and the distance from the shielding layer to the nearest point of the current transformer under test are used as reference values ​​to serve as the starting point for parameter adjustment. Subsequently, a preset parameter adjustment range and a fixed step size are adopted, which is reflected as a fixed difference, to simultaneously adjust the combination of the two reference values ​​within the preset range.

[0039] This invention specifically employs a full-factor design method, which involves synchronously matching all nearest-point distance values ​​for each average thickness value to form a two-dimensional parameter matrix. For any parameter combination in the baseline value combination, the lightning simulation experiment described in the data acquisition module is re-executed. This step covers all gradient points and lightning impact simulations. During the experiment, lightning strikes are simulated and repeated multiple times. Each test is repeated to eliminate the influence of external randomness on the results. Simultaneously, the output current waveform data, including waveform shape and trend, is recorded in real time for subsequent analysis. Time series analysis is performed during calculation, and the fluctuation value of the output current of the current transformer under test is extracted within a fixed period T-second window. The fluctuation value of the output current of the current transformer under test is calculated using the following formula:

[0040] in, This represents the average thickness of the metal shielding layer at various points. This is the distance from the metal shielding layer to the nearest point of the current transformer under test. and All are inversely proportional to the current fluctuation value, therefore, they are also indirectly related to... and To calculate the degree of the aforementioned current offset; This is the constant representing the fluctuation rate of the output current during lightning impulse. Determined by the characteristics of the current transformer under test, and It is directly proportional to the current fluctuation value.

[0041] The float time of the output current of the current transformer under test is calculated using the following formula:

[0042] in: The output current float time ratio constant of the lightning impulse is given. Determined by the characteristics of the current transformer under test, its value is directly proportional to the current fluctuation; and and The baseline value determined by the initial test is used as the baseline center point. The subsequent parameter adjustment range is based on the preset parameters and a fixed step size is set. The parameter combination adopts a full factorial design, and the distance values ​​of all nearest points are matched synchronously for each average thickness to form a two-dimensional parameter matrix.

[0043] The and The calculation process for parameter adjustment is as follows: First, fix the average thickness to a specific value, then iterate through all metal shielding layers at fixed intervals to the nearest point distance value to the current transformer under test, and perform tests. After completing the thickness layer, adjust the average thickness by a fixed difference, and then repeat the traversal process of the nearest point distance value for the next average thickness, finally generating... Group parameter combinations, where The number of times the average thickness is adjusted to a fixed difference; This represents the number of times the nearest point distance value is traversed.

[0044] Step S4 outputs a test report, which includes at least three core components: a peak value comparison table, interference suppression rate, and recommended solutions. The peak value comparison table integrates output current fluctuation values ​​and output current fluctuation time data from all experimental scenarios and compares them horizontally with benchmark test results for unshielded layers. For example, it arranges the data according to parameter combinations of average thickness and nearest-point distance values ​​at various locations of different metal shielding layers, vertically marking the maximum current fluctuation value and output current fluctuation time, and calculating the interference suppression rate to quantify the improvement in shielding effectiveness. This report provides detailed information on peak value variation trends under different metal shielding layer thicknesses and volumes to assess the potential for optimizing shielding effectiveness.

[0045] It should be noted that the observed output current fluctuation amplitudes under all experimental scenarios are systematically integrated. Its corresponding output current float time These data were then compared and analyzed item by item with the benchmark test results under unshielded conditions, ultimately forming a unified peak comparison table. This table, horizontally, clearly lists multiple parameter combinations consisting of different average shielding layer thickness parameters and the nearest point distance values ​​of different electromagnetic interference sources; vertically, it clearly indicates the maximum measured output current fluctuation value corresponding to each parameter combination in the experimental scenario. and output current float time Based on the above comparative data, the interference suppression rate of each set of parameters relative to the baseline operating condition was further calculated and recorded. The interference suppression rate is used to quantitatively evaluate the shielding effectiveness, intuitively show the weakening effect of the shielding layer on lightning interference, and the peak value comparison table can be used to obtain the peak value change information trend under different metal shielding layer thicknesses and volumes, thereby evaluating the optimization potential of shielding effectiveness.

[0046] Subsequently, a multi-objective optimization algorithm was used to adjust the output current fluctuation value. The instantaneous degree of interference and the output current fluctuation time represented by these parameters. The system stability represented is used as the core performance indicator, and the volume and cost of the metal shielding layer are used as constraints, with the cost being proportional to the amount of material used. The algorithm automatically traverses the parameter space to find the optimal solution set that maximizes the interference suppression rate while keeping the cost controllable. This process uses a two-dimensional parameter space consisting of the average shielding layer thickness and the minimum installation distance of the interference source as the search domain, and employs a non-dominated sorting genetic algorithm for multi-objective optimization. Recommended solutions are generated, and 3-5 sets of optimal parameter combinations are selected from the optimal solution set. For example, in this embodiment, ,and hour, The cost is reduced to 15% of the baseline value while increasing by only 20%. Furthermore, the current offset is calculated to obtain the final current offset data for the current transformer.

[0047] Based on this, the test report employs an algorithm based on a trade-off model to calculate the shielding effect and cost factors, including material usage and processing costs, thereby scientifically selecting the optimal parameter combination as the recommended solution. In this step, the test report outputs data in various user-friendly formats, including visual charts and textual conclusions. The visual charts specifically include line graphs and heatmaps, making the test results more intuitive, easier to interpret, and providing decision support.

[0048] Specifically, it is displayed using a line chart. and and The report presents a negative correlation trend, a heatmap illustrating the cost-suppression rate trade-off, and includes clearly recommended shielding engineering parameters and the expected improvement in electromagnetic compatibility levels. For example, it recommends using an aluminum shielding layer with an average thickness ≥3.5mm and an installation distance ≤1.2m, which is expected to suppress peak lightning interference to below 15% and reduce current deviation by 20%, ensuring that the report is both data-driven and actionable.

[0049] The formulas mentioned in the above embodiments are all dimensionless calculations. The formulas are derived from software simulations using a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0050] Please refer to again Figure 2 As shown, corresponding to the electromagnetic compatibility testing optimization method for current transformers in Embodiment 1 of the present invention, Embodiment 2 of the present invention also provides an electromagnetic compatibility testing optimization device for current transformers, comprising: The data simulation acquisition module is used to conduct lightning strike simulation tests in a pre-constructed lightning strike simulation scenario, and to acquire the simulated lightning distance, the input lightning current amplitude, the output current fluctuation value of the current transformer under test, and the output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning impact to the recovery of the output current to a stable state. The immunity peak analysis module is used to calculate the current deviation based on the collected test data using time series analysis and sliding window analysis techniques. It identifies the dynamic response type of the current transformer under test based on the changing characteristics of the current deviation and generates a peak report containing immunity. The shielding effectiveness optimization module is used to collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, the average thickness and nearest point distance are synchronously adjusted according to a preset fixed step size to form a two-dimensional parameter matrix. For each set of parameter combinations, the lightning strike simulation test in step S1 is repeated to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. The decision output configuration module is used to compare the test results of each parameter combination with the benchmark test results without a shielding layer, calculate the interference suppression rate, and use a multi-objective optimization algorithm to optimize with the goal of maximizing the shielding effect and minimizing the cost, select the optimal parameter combination and output a test report.

[0051] Corresponding to the electromagnetic compatibility testing optimization method for current transformers in Embodiment 1 of the present invention, Embodiment 3 of the present invention also provides an electromagnetic compatibility testing optimization device for current transformers, comprising: One or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more applications are configured to execute the current transformer electromagnetic compatibility test optimization method.

[0052] Corresponding to the current transformer electromagnetic compatibility test optimization method in Embodiment 1 of the present invention, Embodiment 4 of the present invention also provides a computer program product, including computer instructions, which instruct a computer device to perform the operation corresponding to the current transformer electromagnetic compatibility test optimization method.

[0053] Preferably, the processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor, or the processor can be any conventional processor. The processor is the control center of the device, connecting various parts of the device through various interfaces and lines.

[0054] The memory mainly includes a program storage area and a data storage area. The program storage area can store the operating system, applications required for at least one function, etc., while the data storage area can store related data, etc. Furthermore, the memory can be a high-speed random access memory, or a non-volatile memory, such as a plug-in hard drive, a SmartMedia Card (SMC), a Secure Digital (SD) card, and a Flash Card, or other volatile solid-state storage devices.

[0055] It should be noted that the above-mentioned devices may include, but are not limited to, processors and memory, as will be understood by those skilled in the art.

[0056] For the working principle and process of the above embodiments, please refer to the description of Embodiment 1 of the present invention, which will not be repeated here.

[0057] Compared with existing technologies, this invention has the following significant advantages: This invention effectively solves the technical shortcomings of existing current transformer lightning impulse electromagnetic compatibility testing, which suffers from a single dimension, reliance on manual experience for shielding optimization, and difficulty in balancing performance and cost. By combining lightning speed simulation with time series and sliding window analysis techniques, it accurately captures the fluctuation time while collecting the output current fluctuation value to quantitatively evaluate the equipment's lightning transient response characteristics. Furthermore, it employs a full-factor design method to adjust the average thickness of the metal shielding layer and the installation distance in a coordinated manner and construct a two-dimensional parameter matrix, systematically quantifying the coupling law between shielding geometry and electromagnetic interference, thus completely eliminating the need for... This invention overcomes the limitations of traditional single-variable testing. It integrates interference suppression rate, dynamic response time, shielding volume, and cost into a multi-objective optimization system, replacing traditional experience-based parameter tuning with a data-driven approach. This scientifically balances the performance requirements of current transformers against lightning interference with engineering economic benefits. Furthermore, it outputs directly applicable recommended engineering parameters for the shielding layer, achieving a technological leap from qualitative protection to quantitative optimization. This significantly improves the accuracy of electromagnetic compatibility testing for current transformers and the engineering applicability of the shielding optimization scheme, making the optimized current transformer's resistance to lightning strike interference more aligned with the actual operational needs of smart grids.

[0058] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. An optimized method for electromagnetic compatibility testing of current transformers, characterized in that, include: Step S1: Conduct a lightning strike simulation test in a pre-constructed lightning strike simulation scenario, and collect the simulated lightning distance, input lightning current amplitude, output current fluctuation value of the current transformer under test, and output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning strike to the recovery of the output current to a stable state. Step S2: Based on the collected test data, the current offset is calculated using time series analysis and sliding window analysis techniques. The dynamic response type of the current transformer under test is identified according to the changing characteristics of the current offset, and a peak report including the immunity is generated. Step S3: Collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, adjust the average thickness and nearest point distance synchronously according to the preset fixed step size to form a two-dimensional parameter matrix. Repeat the lightning strike simulation test of step S1 for each set of parameter combinations to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. Step S4: Compare the test results of each parameter combination with the benchmark test results without shielding layer, calculate the interference suppression rate, use a multi-objective optimization algorithm to optimize with the goal of maximizing shielding effect and minimizing cost, select the optimal parameter combination and output the test report.

2. The method according to claim 1, characterized in that, In step S1, the pre-constructed lightning strike simulation scenario is constructed in the following manner: Designate an isolation zone to isolate external electromagnetic noise; Multiple gradient points are evenly spaced within a preset gradient range to simulate the distance between a lightning strike and the current transformer under test. satisfy ,in, The maximum length of the experimental scenario. The equal spacing length of the gradient points; and the lightning strike simulation test is repeated, with each repetition covering all gradient points to eliminate random errors.

3. The method according to claim 1, characterized in that, In step S2, the current offset is calculated using the following formula: in, For current offset, For the first The output current fluctuation value in each calculation cycle The periodic sequence calculated for current offset. To input the amplitude of the lightning current, The number of times the current offset was sampled. For the first Output current fluctuation time in each calculation cycle To simulate lightning distance; the dynamic response types include fast response type and continuous oscillation type.

4. The method according to claim 1, characterized in that, In step S2, the data in the peak report containing immunity includes: maximum current offset and occurrence timestamp, total output current floating time for each cycle, current recovery rate, and dynamic response type distribution statistics.

5. The method according to claim 1, characterized in that, In step S3, the specific process of synchronously adjusting the average thickness and the nearest point distance according to a preset fixed step size is as follows: First, fix the average thickness of the metal shielding layer to a certain value, traverse all nearest point distance values ​​at fixed intervals to complete the test, then adjust the average thickness and repeat the above nearest point distance value traversal process to finally generate... Group parameter combinations, where The number of times the average thickness is adjusted to a fixed difference; This represents the number of times the nearest point distance value is traversed; and the corresponding output current fluctuation value in the scenario is... The output current float time is ,in, This represents the average thickness of the metal shielding layer at various points. This is the distance from the metal shielding layer to the nearest point of the current transformer under test. This is the constant representing the fluctuation rate of the output current during lightning impulse. The output current floating time ratio constant of lightning impulse is denoted as .

6. The method according to claim 1, characterized in that, In step S4, the multi-objective optimization algorithm is a non-dominated sorting genetic algorithm. It uses a two-dimensional parameter space consisting of the average thickness of the shielding layer and the minimum installation distance of the interference source as the search domain to traverse the parameter space and select the optimal parameter combination from the found optimal solution set.

7. The method according to claim 5, characterized in that, In step S4, the test report includes a peak comparison table, interference suppression rate, and recommended optimal parameter combination scheme. The output format of the test report includes visual charts and textual conclusions. The visual charts include displays... and and The text presents a line graph showing the negative correlation trend and a heatmap showing the cost-interference suppression rate trade-off. The conclusions include shielding layer engineering parameters and the expected improvement in electromagnetic compatibility level.

8. A current transformer electromagnetic compatibility testing and optimization device, characterized in that, include: The data simulation acquisition module is used to conduct lightning strike simulation tests in a pre-constructed lightning strike simulation scenario, and to acquire the simulated lightning distance, the input lightning current amplitude, the output current fluctuation value of the current transformer under test, and the output current fluctuation time. The output current fluctuation time is the total duration from the initial moment of the lightning impact to the recovery of the output current to a stable state. The immunity peak analysis module is used to calculate the current deviation based on the collected test data using time series analysis and sliding window analysis techniques. It identifies the dynamic response type of the current transformer under test based on the changing characteristics of the current deviation and generates a peak report containing immunity. The shielding effectiveness optimization module is used to collect the initial average thickness and initial nearest point distance of the metal shielding layer as reference values. Using the full factorial design method, the average thickness and nearest point distance are synchronously adjusted according to a preset fixed step size to form a two-dimensional parameter matrix. For each set of parameter combinations, the lightning strike simulation test in step S1 is repeated to obtain the output current fluctuation value and output current fluctuation time under the corresponding scenario. The decision output configuration module is used to compare the test results of each parameter combination with the benchmark test results without a shielding layer, calculate the interference suppression rate, and use a multi-objective optimization algorithm to optimize with the goal of maximizing the shielding effect and minimizing the cost, select the optimal parameter combination and output a test report.

9. A current transformer electromagnetic compatibility testing and optimization device, characterized in that, include: One or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, the one or more applications being configured to perform the current transformer electromagnetic compatibility test optimization method as described in any one of claims 1 to 7.

10. A computer program product, characterized in that, Includes computer instructions that instruct a computer device to perform operations corresponding to the electromagnetic compatibility test optimization of the current transformer as described in any one of claims 1 to 7.

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