Frequency response measurement method and system based on amplitude adaptive adjustment and nonlinear interpolation

Abstract

The invention provides a frequency response measurement method and system based on amplitude adaptive adjustment and nonlinear interpolation, and the method comprises the steps: determining the disturbance amplitude of a test frequency point based on each test frequency point of a tested object according to the pre-calculated safety operation threshold information of the test frequency point; performing frequency disturbance on the tested object according to the disturbance amplitude of the test frequency point to obtain the frequency response of the tested object at the test frequency point; based on the frequency response of the tested object at the test frequency point and the safe operation threshold information, correcting the disturbance amplitude of the test frequency point to obtain frequency characteristic data of the tested object at the test frequency point; according to the frequency characteristic data of the tested object at each test frequency point, utilizing a nonlinear interpolation algorithm to output a frequency response characteristic curve of the tested object; by correcting the disturbance amplitude, the modulation error of the disturbance amplitude can be reduced, and by combining the frequency response characteristic curve output by the nonlinear interpolation algorithm, the precision and reliability of frequency response measurement can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of frequency response measurement, and in particular to a frequency response measurement method and system based on amplitude adaptive adjustment and nonlinear interpolation. Background Art

[0002] Frequency response measurement is a crucial analytical tool, widely used in engineering and science to evaluate the response characteristics of systems, equipment, or structures at different frequencies. In power systems, frequency response measurements are primarily used to analyze and optimize the system's dynamic performance, including detecting and evaluating the stability, response speed, and damping characteristics of power equipment. This technique can help identify and diagnose system problems, such as harmonic distortion and oscillation, enabling effective monitoring and maintenance of equipment such as transformers, generators, and transmission lines. Frequency response measurements can also be used to design and optimize controllers to improve the stability and reliability of power systems under load fluctuations and fault conditions.

[0003] Frequency response measurement methods based on sinusoidal signals, due to their high measurement accuracy and universal applicability, are applicable to both linear and nonlinear systems, thus playing an irreplaceable role in frequency response measurement. However, traditional sinusoidal swept-frequency methods maintain a fixed amplitude at each frequency point, while the frequency response characteristics of the measured object vary. This results in the same disturbance amplitude producing different responses at different frequencies. Excessively large responses can trigger nonlinear effects in the system, even threatening its normal operation, reducing the adaptability of this method. To address this issue, existing technologies have made some improvements to improve measurement safety and reliability. These improvements incorporate adaptive control algorithms to dynamically adjust the amplitude of the disturbance signal, ensuring that frequency response measurements are performed within the system's safety threshold. However, the amplitude adjustment process in existing methods is often overly general, resulting in large modulation errors and reduced measurement accuracy. Furthermore, existing technologies often use linear interpolation to process the frequency characteristic data obtained from frequency response measurements. While this method is simple and fast, it only considers two adjacent data points and cannot fully capture the more complex impedance characteristic curve shape. In frequency bands with rapidly varying impedances, interpolation performance is poor, making it difficult to fully reflect the frequency response characteristics across the entire frequency range. Summary of the Invention

[0004] In order to solve the problem of low frequency response measurement accuracy in the prior art due to large amplitude modulation error of the disturbance signal during frequency response measurement, the present invention proposes a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation, comprising:

[0005] Based on each test frequency point of the measured object, determining the disturbance amplitude of the test frequency point according to pre-calculated safe operation threshold information of the test frequency point;

[0006] Performing frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point to obtain a frequency response of the object under test at the test frequency point;

[0007] Based on the frequency response of the measured object at the test frequency point and the safe operation threshold information, the disturbance amplitude of the test frequency point is corrected to obtain the frequency characteristic data of the measured object at the test frequency point;

[0008] According to the frequency characteristic data of the measured object at each test frequency point, a frequency response characteristic curve of the measured object is outputted using a nonlinear interpolation algorithm.

[0009] Optionally, the correcting the disturbance amplitude of the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information to obtain the frequency characteristic data of the measured object at the test frequency point includes:

[0010] Determining whether the disturbance amplitude meets a preset safety requirement based on the frequency response of the measured object at the test frequency point and the safe operation threshold information;

[0011] If satisfied, calculate the frequency characteristic data of the test frequency point according to the disturbance amplitude and frequency response of the test frequency point;

[0012] If not, the disturbance amplitude of the test frequency point is corrected according to the frequency response of the test frequency point and the safe operation threshold information, and the frequency characteristic data of the test frequency point is calculated according to the corrected disturbance amplitude.

[0013] Optionally, the correcting the disturbance amplitude of the test frequency point according to the frequency response and safe operation threshold information of the test frequency point, and calculating the frequency characteristic data of the test frequency point according to the corrected disturbance amplitude, includes:

[0014] Calculating a proportional adjustment coefficient of the disturbance amplitude based on the frequency response of the test frequency point and the safe operation threshold information;

[0015] Correcting the disturbance amplitude according to a proportional adjustment coefficient of the disturbance amplitude;

[0016] When the corrected disturbance amplitude meets the safety requirement, the frequency characteristic data of the measured object at the test frequency point is calculated.

[0017] Optionally, the safe operation threshold information of the test frequency point includes the following calculation process:

[0018] Obtaining operating information of the object under test in a steady-state condition at the test frequency point;

[0019] Calculating the safe operation threshold information of the measured object at the test frequency point according to the operation information;

[0020] The operation information includes one or more of the following: voltage information and current information.

[0021] Optionally, determining the disturbance amplitude of the test frequency point according to pre-calculated safe operation threshold information of the test frequency point includes:

[0022] Obtaining a safe disturbance amplitude range for the test frequency point based on pre-calculated safe operation threshold information for the test frequency point;

[0023] The maximum value of the safe disturbance amplitude range is determined as the disturbance amplitude of the test frequency point.

[0024] Optionally, performing frequency perturbation on the object under test according to the disturbance amplitude of the test frequency point to obtain a frequency response of the object under test at the test frequency point includes:

[0025] generating a disturbance signal at the test frequency point according to the disturbance amplitude at the test frequency point;

[0026] Performing frequency perturbation on the object under test according to the disturbance signal at the test frequency point to obtain a frequency response of the object under test at the test frequency point;

[0027] The frequency response includes one or more of the following: output signal amplitude, phase change, voltage change and current change.

[0028] Optionally, before determining the disturbance amplitude of each test frequency point based on the test frequency point of the measured object and according to pre-calculated safe operation threshold information of the test frequency point, the method further includes:

[0029] Obtain the starting test frequency, ending test frequency and number of test frequency points of the object under test;

[0030] Performing logarithmic coordinate conversion on the starting test frequency and the ending test frequency;

[0031] Calculating the non-equidistant measurement points of the object under test using the Chebyshev method based on the number of test frequency points, the starting test frequency and the ending test frequency after coordinate conversion;

[0032] The non-equidistant measurement points of the measured object are used as test frequency points for frequency response measurement of the measured object.

[0033] Based on the same inventive concept, the present invention also provides a frequency response measurement system based on amplitude adaptive adjustment and nonlinear interpolation, comprising:

[0034] A disturbance determination module is configured to determine, based on each test frequency point of the measured object and according to pre-calculated safe operation threshold information of the test frequency point, a disturbance amplitude of the test frequency point;

[0035] A frequency perturbation module, configured to perform frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point, so as to obtain a frequency response of the object under test at the test frequency point;

[0036] an amplitude correction module, configured to correct the disturbance amplitude of the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information, and obtain frequency characteristic data of the measured object at the test frequency point;

[0037] The result output module is used to output the frequency response characteristic curve of the measured object by using a nonlinear interpolation algorithm according to the frequency characteristic data of the measured object at each test frequency point.

[0038] Optionally, the amplitude correction module includes:

[0039] A safety judgment submodule is used to judge whether the disturbance amplitude meets the preset safety requirements based on the frequency response of the measured object at the test frequency point and the safe operation threshold information;

[0040] a characteristic output submodule, configured to calculate frequency characteristic data of the test frequency point according to the disturbance amplitude and frequency response of the test frequency point when the disturbance amplitude meets the preset safety requirements;

[0041] The dynamic correction submodule is used to correct the disturbance amplitude of the test frequency point according to the frequency response and safe operation threshold information of the test frequency point when the disturbance amplitude does not meet the preset safety requirements, and calculate the frequency characteristic data of the test frequency point according to the corrected disturbance amplitude.

[0042] Optionally, the dynamic correction submodule includes:

[0043] A coefficient calculation unit, configured to calculate a proportional adjustment coefficient of the disturbance amplitude according to the frequency response of the test frequency point and the safe operation threshold information;

[0044] a correction unit, configured to correct the disturbance amplitude according to a proportional adjustment coefficient of the disturbance amplitude;

[0045] The characteristic calculation unit is used to calculate the frequency characteristic data of the object under test at the test frequency point when the corrected disturbance amplitude meets the safety requirement.

[0046] Optionally, the frequency response measurement system further includes a disturbance determination module, including:

[0047] An information acquisition submodule is used to obtain the operating information of the object under test in a steady-state condition at the test frequency point;

[0048] A threshold determination submodule, configured to calculate the safe operation threshold information of the measured object at the test frequency point based on the operation information;

[0049] The operation information includes one or more of the following: voltage information and current information.

[0050] Optionally, the disturbance determination module includes:

[0051] A range calculation submodule, configured to obtain a safe disturbance amplitude range of the test frequency point based on pre-calculated safe operation threshold information of the test frequency point;

[0052] The amplitude setting submodule is used to determine the maximum value of the safety disturbance amplitude range as the disturbance amplitude of the test frequency point.

[0053] Optionally, the frequency perturbation module includes:

[0054] A signal generation submodule, configured to generate a disturbance signal at the test frequency point according to the disturbance amplitude at the test frequency point;

[0055] A frequency response submodule, configured to perform frequency perturbation on the object under test according to the perturbation signal at the test frequency point, and obtain a frequency response of the object under test at the test frequency point;

[0056] The frequency response includes one or more of the following: output signal amplitude, phase change, voltage change and current change.

[0057] Optionally, the frequency response measurement system further includes: a frequency point generation module, including:

[0058] The data acquisition submodule is used to obtain the starting test frequency, ending test frequency and number of test frequency points of the object under test;

[0059] A coordinate conversion submodule, configured to perform logarithmic coordinate conversion on the starting test frequency and the ending test frequency;

[0060] A measurement point generation submodule, configured to calculate the non-equidistant measurement points of the measured object using a Chebyshev method based on the number of test frequency points, the starting test frequency and the ending test frequency after coordinate conversion;

[0061] The frequency point output submodule is used to use the non-equidistant measurement points of the object under test as the test frequency points for frequency response measurement of the object under test.

[0062] In another aspect, the present invention further provides an electronic device, comprising: at least one processor and a memory; the memory and the processor are connected via a bus;

[0063] The memory is used to store one or more programs;

[0064] When the one or more programs are executed by the at least one processor, the frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation as described above is implemented.

[0065] In another aspect, the present invention further provides a computer-readable storage medium having an execution program stored thereon. When the execution program is executed, the frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation as described above is implemented.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] The present invention provides a frequency response measurement method and system based on amplitude adaptive adjustment and nonlinear interpolation, comprising: determining, based on each test frequency point of a measured object and according to pre-calculated safe operation threshold information of the test frequency point, a disturbance amplitude of the test frequency point; performing frequency disturbance on the measured object according to the disturbance amplitude of the test frequency point to obtain a frequency response of the measured object at the test frequency point; correcting the disturbance amplitude of the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information to obtain frequency characteristic data of the measured object at the test frequency point; and outputting a frequency response characteristic curve of the measured object using a nonlinear interpolation algorithm based on the frequency characteristic data of the measured object at each test frequency point. The present invention can reduce the modulation error of the disturbance amplitude by correcting the disturbance amplitude, and can increase the accuracy and reliability of frequency response measurement by combining the frequency response characteristic curve output by the nonlinear interpolation algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 A flow chart of a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0069] Figure 2 A schematic diagram showing the influence of different interpolation points on the interpolation result when the Chebyshev method is used to determine the measurement frequency point in a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0070] Figure 3 A schematic diagram of the adjustment process of disturbance amplitude correction in a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0071] Figure 4A schematic diagram illustrating the influence of the derivative of an interpolation node on the interpolation result when a nonlinear interpolation algorithm is used in a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0072] Figure 5 Schematic diagram of amplitude response results using different methods for frequency response measurement;

[0073] Figure 6 Schematic diagram of phase response results using different methods for frequency response measurement;

[0074] Figure 7 A schematic diagram of the overall framework of a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0075] Figure 8 A schematic diagram of the structure of a frequency response measurement system based on amplitude adaptive adjustment and nonlinear interpolation provided by the present invention;

[0076] Figure 9 This is a structural diagram of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0077] The present invention provides a frequency response measurement method, system, device and medium based on amplitude adaptive adjustment and nonlinear interpolation. The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0078] Example 1:

[0079] The present invention provides a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation, the flow chart is as follows: Figure 1 As shown, including:

[0080] Step 1: Based on each test frequency point of the object under test, determine the disturbance amplitude of the test frequency point according to the pre-calculated safe operation threshold information of the test frequency point;

[0081] Step 2: Perform frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point to obtain the frequency response of the object under test at the test frequency point;

[0082] Step 3: Based on the frequency response and safe operation threshold information of the object under test at the test frequency point, the disturbance amplitude at the test frequency point is corrected to obtain the frequency characteristic data of the object under test at the test frequency point;

[0083] Step 4: Based on the frequency characteristic data of the object under test at each test frequency point, a nonlinear interpolation algorithm is used to output the frequency response characteristic curve of the object under test.

[0084] In practical applications, in order to effectively perform the frequency response measurement process, it is necessary to clarify and optimize the setting method of the test frequency points. That is, it is necessary to set the starting test frequency, ending test frequency and number of test frequency points in advance, and calculate the position of the test frequency points, so as to improve the accuracy and efficiency of frequency response characteristic extraction. Specifically:

[0085] In one implementation, before determining the disturbance amplitude of the test frequency points based on the test frequency points of the object under test and according to pre-calculated safe operation threshold information of the test frequency points, step 1 may include:

[0086] Obtain the starting test frequency, ending test frequency and number of test frequency points of the object under test;

[0087] Perform logarithmic coordinate transformation on the starting test frequency and the ending test frequency;

[0088] Based on the number of test frequency points, the starting test frequency and the ending test frequency after coordinate transformation, the Chebyshev method is used to calculate the non-equidistant measurement points of the measured object;

[0089] The non-equidistant measurement points of the object under test are used as the test frequency points for frequency response measurement of the object under test;

[0090] For example, the above expression for calculating the non-equidistant measurement points of the measured object using the Chebyshev method can be as follows:

[0091]

[0092] Among them, x k represents the position of the kth non-equidistant measurement point; [a, b] is a given interval; n represents the total number of Chebyshev measurement points (i.e., non-equidistant measurement points); in this example, Chebyshev non-equidistant measurement points are used to minimize oscillation during the interpolation process and avoid the Runge phenomenon. The influence of different interpolation nodes on the interpolation results is shown in the following figure. Figure 2 As shown in the example, finding the Chebyshev measurement point is actually to minimize the maximum value of the interpolation error. In a given interval [a, b], the positions of n Chebyshev measurement points can be calculated by the expression in this example. Figure 2 As can be seen from the content, when interpolating at equidistant test frequency points, the Runge phenomenon may occur (that is, the interpolation polynomial produces violent oscillations at both ends of the interval in the case of high degrees, causing the interpolation result to deviate seriously from the true curve). The non-equidistant nodes generated by the Chebyshev method (densely distributed at both ends of the frequency interval) can minimize the maximum value of the interpolation error and avoid the Runge phenomenon. The interpolation curve is highly consistent with the true curve, especially at the two ends of the frequency interval. The error is significantly reduced, thereby more accurately approximating the true frequency response characteristics.

[0093] In this implementation, by introducing the Chebyshev method to calculate non-equidistant test frequency points in logarithmic coordinates, it is possible to optimize the configuration of test points in frequency response measurements. Users only need to input a few parameters such as the starting test frequency, the ending test frequency, and the number of test frequency points to automatically generate non-equidistant test frequency points covering the frequency band to be measured, and set the first disturbance frequency as the starting frequency, thereby simplifying the test configuration process. While maintaining measurement accuracy, this implementation effectively reduces the steps of manual user participation, improving the convenience of measurement and engineering practicality. Compared with the equidistant sampling method, the non-equidistant point design using the Chebyshev distribution can densely distribute test points at both ends of the frequency, enhance the ability to resolve the edge features of the frequency response curve, and effectively improve the accuracy of the overall frequency response curve restoration. At the same time, the measurement requires few input parameters and the setup process is simple, which lowers the threshold for use. It is especially suitable for engineering application scenarios with high requirements for operational efficiency and accuracy.

[0094] Through the above implementation, a series of non-equidistant test frequency points of the object under test within the target frequency band can be obtained, thus providing a basis for amplitude control in the subsequent frequency response measurement process. On this basis, to further improve the safety and accuracy of the measurement, it is possible to consider combining the safe operation threshold information of each test frequency point to determine the disturbance amplitude. Specifically:

[0095] In one implementation, the process of determining the disturbance amplitude of the test frequency point according to the pre-calculated safe operation threshold information of the test frequency point in step 1 may include:

[0096] According to the pre-calculated safe operation threshold information of the test frequency point, the safe disturbance amplitude range of the test frequency point is obtained;

[0097] The maximum value of the safe disturbance amplitude range is determined as the disturbance amplitude of the test frequency point.

[0098] In this implementation, the safe operation threshold information of the test frequency point may include the following calculation process:

[0099] Obtaining the operating information of the object under test in steady-state conditions at the test frequency point;

[0100] Calculate the safe operation threshold information of the tested object at the test frequency point based on the operation information;

[0101] The operation information may include one or more of the following: voltage information and current information;

[0102] In this implementation, by obtaining the steady-state operation information of the object under test at each test frequency point, such as voltage and current information, the safe operation threshold information of the corresponding frequency point is calculated, such as the voltage safety threshold v max and current safety threshold i max, and determine the disturbance amplitude of each test frequency point accordingly. Taking current disturbance as an example, the disturbance amplitude can be set to the maximum current disturbance i that the object under test can withstand. max , making the initial injected disturbance as large as possible while ensuring safety. In this way, the setting of the disturbance signal can fully utilize the maximum disturbance amplitude within the tolerable range of the measured object, which not only improves the signal-to-noise ratio of the initial frequency response measurement, but also enhances the resolution and accuracy of the frequency characteristic data. In addition, during the subsequent disturbance amplitude adjustment process, the algorithm can dynamically adjust parameters based on the actual operating characteristics of the measured object, showing good adaptability. This mechanism of setting the disturbance amplitude based on steady-state characteristics ensures that the measurement process has higher measurement accuracy and engineering practicality while meeting safety requirements.

[0103] Through the above implementation, a disturbance amplitude with a safety margin can be determined for different test frequencies, ensuring that the disturbance signal has sufficient response strength without affecting the normal operation of the object under test. Based on this disturbance amplitude, it is possible to consider generating a corresponding disturbance signal and injecting it into the object under test to obtain its frequency response information at each test frequency. Specifically:

[0104] In one implementation, the process of performing frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point in step 2 to obtain the frequency response of the object under test at the test frequency point may include:

[0105] Generate a disturbance signal at the test frequency point according to the disturbance amplitude at the test frequency point;

[0106] Perform frequency disturbance on the object under test according to the disturbance signal of the test frequency point to obtain the frequency response of the object under test at the test frequency point;

[0107] Wherein, the frequency response includes one or more of the following: output signal amplitude, phase change, voltage change and current change;

[0108] In this implementation, a disturbance signal is generated according to the disturbance amplitude of the test frequency point, and the disturbance signal is injected into the object under test, thereby achieving frequency disturbance of the object under test. p and the current disturbance amplitude i p For example, under the condition that the disturbance signal is a small sinusoidal signal, i is applied to the object under test. p The amplitude of the disturbance is detected, and the response signal v at this frequency is collected synchronously r, the frequency response information of the object under test at the test frequency point can be obtained. The frequency response can include the amplitude, phase, voltage change or current change of the output signal, etc., which can fully reflect the dynamic characteristics of the object under test to different frequency disturbances. In this way, the application of the disturbance signal and the acquisition of the response data are automatically linked and synchronized, ensuring the real-time and accurate frequency response measurement. In addition, by performing frequency disturbances at a disturbance amplitude that the object under test can tolerate, the signal-to-noise ratio during the measurement process can be effectively improved, which is conducive to improving the reliability of the frequency characteristic data.

[0109] Through the above implementation, the frequency response information of the measured object under the corresponding disturbance conditions at each test frequency point can be obtained, thereby reflecting its dynamic characteristics under the action of a specific disturbance amplitude. Based on these frequency response results, it is possible to consider combining the safe operation threshold information to further judge the rationality of the current disturbance amplitude and correct the disturbance amplitude that does not meet the requirements to obtain more accurate and reliable frequency characteristic data. Specifically:

[0110] In one implementation, the process of correcting the disturbance amplitude at the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information in step 3 to obtain the frequency characteristic data of the measured object at the test frequency point may include:

[0111] Based on the frequency response and safe operation threshold information of the object under test at the test frequency point, determine whether the disturbance amplitude meets the preset safety requirements;

[0112] If satisfied, calculate the frequency characteristic data of the test frequency point based on the disturbance amplitude and frequency response of the test frequency point;

[0113] If not, the disturbance amplitude of the test frequency point is corrected according to the frequency response and safe operation threshold information of the test frequency point, and the frequency characteristic data of the test frequency point is calculated according to the corrected disturbance amplitude;

[0114] In this implementation, by combining the frequency response of the object under test at the test frequency point with the safe operation threshold information, it is possible to effectively determine whether the current disturbance signal poses a risk to system operation. When the judgment result shows that the disturbance amplitude exceeds the safe threshold, the disturbance amplitude is automatically corrected. When the disturbance is within the safe range, the frequency characteristic data of the corresponding test frequency point is calculated based on the current disturbance signal and the frequency response. The acquisition of frequency characteristic data can be achieved by performing a fast Fourier transform (FFT) on the injected disturbance signal and the response signal, thereby extracting the frequency domain characteristic parameters. This process realizes the adaptive adjustment of the disturbance amplitude, ensuring that the test signal has sufficient amplitude without affecting the normal operation of the system, thereby improving the accuracy and availability of the frequency characteristic data. At the same time, by dynamically judging and processing each test frequency point and automatically switching to the next Chebyshev measurement point frequency (test frequency point), it is beneficial to ensure the continuity, safety and efficiency of the entire frequency response measurement process.

[0115] Specifically, the above process of correcting the disturbance amplitude of the test frequency point according to the frequency response of the test frequency point and the safe operation threshold information, and calculating the frequency characteristic data of the test frequency point according to the corrected disturbance amplitude may include:

[0116] Calculate the proportional adjustment coefficient of the disturbance amplitude based on the frequency response of the test frequency point and the safe operation threshold information;

[0117] According to the proportional adjustment coefficient of the disturbance amplitude, the disturbance amplitude is corrected;

[0118] When the corrected disturbance amplitude meets the safety requirements, the frequency characteristic data of the object under test at the test frequency point is calculated;

[0119] For example, the expression corresponding to the above proportional adjustment coefficient can be as follows:

[0120]

[0121] Among them, K represents the proportional adjustment coefficient; v max Indicates the maximum voltage disturbance value allowed by the measured object; v r Represents the frequency response; for example, the modified expression of the above disturbance amplitude can be as follows:

[0122] i′ p =i p ×K;

[0123] Among them, i′ p represents the disturbance amplitude after correction; i p Indicates the disturbance amplitude before correction. When using this method to determine the disturbance amplitude, if the frequency response exceeds the allowable range, it is necessary to adjust the disturbance amplitude of the current frequency point. The specific adjustment process is as follows: Figure 3As shown, firstly, the proportional adjustment coefficient is determined according to the quotient of the maximum voltage disturbance value and the frequency response, and then the product of the disturbance amplitude and the proportional adjustment coefficient is the corrected disturbance amplitude;

[0124] This implementation introduces a proportional adjustment mechanism for the disturbance amplitude, so that when the frequency response exceeds the allowable range, the proportional adjustment coefficient can be calculated based on the quantitative relationship between the frequency response and the safety threshold, and the disturbance amplitude can be corrected accordingly, thereby ensuring that the disturbance signal changes within the acceptable range of the system. The correction process of the disturbance amplitude does not rely on empirical judgment, but is based on the expression K=v max / v r Clearly establishing the theoretical basis for amplitude regulation is conducive to improving the accuracy of disturbance control. This method can effectively avoid measurement errors caused by improper disturbance amplitude setting, and improve the accuracy of frequency characteristic data and the safety of system operation.

[0125] After the current test frequency disturbance is completed, based on the relationship between the test frequency corresponding to the disturbance signal and the termination test frequency determined in step 1, it is determined whether the frequency response measurement is completed (the relationship between the amplitude of the response signal and the system safety operation threshold is determined to determine whether the signal injected during the measurement process endangers the safety of the system operation, thereby ensuring the safety of the measurement process). When the measurement is completed, the frequency characteristic data of the multiple test frequency points obtained are preprocessed (at least including sorting by frequency and deleting duplicate values, so as to facilitate the merging of multiple measurement results of different frequency bands and measurement points in practical applications). For example, the present invention sorts and deletes duplicate values ​​for all acquired frequency characteristic data to improve the performance of subsequent nonlinear interpolation. This measure enables users to more conveniently merge multiple measurement results obtained in different frequency bands and different measurement frequencies, thereby significantly improving the practicality and convenience of the present invention. Finally, the preprocessed data is subjected to nonlinear interpolation processing (for example, Hermite-Hermite interpolation processing can be selected) to obtain a frequency response curve;

[0126] When using this method for Hermite interpolation, different interpolation node derivative information will produce different interpolation results. The influence of the interpolation node derivative on the interpolation result is as follows: Figure 4As shown in the figure, traditional linear interpolation only uses the function values ​​of adjacent data points, resulting in piecewise linear distortion in the frequency band where the impedance changes dramatically (such as near the resonance point), which cannot reflect the true frequency response characteristics. Hermite interpolation not only uses the node function value, but also introduces the first-order derivative information (i.e., the slope of the curve) to make the interpolation result more consistent with the changing trend of the actual curve. Finally, based on the position and function value of the interpolation node, the derivative value of each node is estimated by finite difference calculation, that is, the derivative of the first node is estimated by forward difference, and the derivative of the last node is estimated by backward difference. For the intermediate nodes, the central difference method is used to estimate the derivative. The specific calculation formulas are:

[0127]

[0128] Among them, f ′ (x0) represents the derivative at the test frequency point x0; n represents the total number of test frequency points; i = 1…n-1; f(x i ) represents the test frequency x i The function value of the buck converter to be tested is taken as an example as the test object, and its output impedance is numerically tested. The traditional fixed amplitude sine sweep method, the existing amplitude adjustment sweep method and the method proposed in this invention are used to test together. The measurement results are shown in Figure 2. Figure 5-Figure 6 As shown ( Figure 5 is the amplitude response result, Figure 6 is the phase response result), from Figure 5-Figure 6 It can be seen that when the traditional sweep frequency method with a fixed amplitude is used, there are a total of 7 uncertain frequency points, and the reliability of the measurement results is severely limited. This can be explained that in the existing amplitude adjustment measurement method, there are two points in the adjustment process where amplitude error modulation occurs, resulting in inaccurate measurement results of these frequency points, and the method requires a total of 35 adjustments to achieve all measurements. In contrast, the method proposed in the present invention only requires 8 adjustments to achieve accurate impedance measurement of the entire frequency band, with short measurement time, high measurement accuracy, and the ability to avoid amplitude error modulation. In addition, when there are fewer measurement points, the gap between linear interpolation and theoretical results is large, while the impedance measurement results obtained by using the Hermite interpolation method based on Chebyshev nodes are very close to the theoretical values, achieving high-precision curve reconstruction with a small number of measurement points. Therefore, the above example can illustrate that the method of this method enables a smooth curve close to the true value to be obtained under limited measurement points, which is conducive to improving the accuracy and efficiency of the measurement.

[0129] In summary, the present invention addresses the problem that, during the frequency response measurement process, since the amplitude of each measurement point is fixed, the differences in the frequency response characteristics of different measured objects will lead to the generation of nonlinear effects. The existing technology introduces an adaptive amplitude control algorithm for adjustment, but the accuracy of the amplitude adjustment is insufficient, which may cause the disturbance amplitude to be too low, reducing the accuracy of the frequency response measurement, or the amplitude to be too high, triggering the nonlinear effect of the measured object, thereby affecting the accuracy of the measurement results. At the same time, the linear interpolation method used in the existing technology, although it can improve the fitting accuracy of the measurement data, is prone to interpolation stability problems as the number of measurement points increases, resulting in unstable frequency response measurement results and difficulty in accurately reflecting the true frequency response characteristics of the system. To solve the above problems, the present invention proposes a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation. The overall framework diagram is shown in FIG. Figure 7 As shown, first, for the starting frequency, ending frequency and number of test frequency points input by the user, the Chebyshev measurement point is calculated to determine the test frequency point, and the safety threshold is calculated according to the system information of the object under test, and the disturbance measurement response is injected. When the measurement response result meets the safety requirements, the frequency characteristic data of each test frequency point is output; when the measurement response result does not meet the safety requirements, the disturbance amplitude is corrected by calculating the amplitude adjustment coefficient (that is, the proportional adjustment coefficient) until the measurement response result meets the safety requirements, and the frequency characteristic data of each test frequency point is output; finally, a nonlinear interpolation method is used to improve the measurement accuracy according to the output frequency characteristic data of each test frequency point, such as the Lagrange interpolation method, the Newton interpolation method and the Hermite interpolation method. Preferably, the present invention uses the Hermite interpolation method for nonlinear interpolation.

[0130] The present invention automatically adjusts the disturbance amplitude and frequency through an intelligent algorithm, enabling a highly automated measurement process and significantly improving the system's practicality. To address the Runge phenomenon, a problem often encountered in traditional nonlinear interpolation methods when increasing the measurement frequency, resulting from high-order polynomials, the method utilizes Chebyshev measurement points combined with nonlinear interpolation data processing. This method not only effectively avoids the impact of the Runge phenomenon on the stability of measurement results, but also achieves accurate interpolation results close to the true value with fewer measurement points. Furthermore, through optimized algorithm design, the present invention achieves proportional regulation of the disturbance amplitude based on the system response with only a low computational effort, significantly reducing the number of adjustments and fundamentally addressing the prior art issue of reduced measurement accuracy due to amplitude mismodulation. It is particularly worth noting that the combination of Chebyshev measurement points and the Hermite interpolation method adopted by the present invention achieves three major breakthroughs while ensuring measurement accuracy: first, only a small number of measurement points are required to obtain a smooth curve close to the true value; second, the Runge phenomenon in the interpolation process is completely avoided; and third, the overall measurement accuracy is significantly improved. These technical advantages make the present invention have significant characteristics such as independence from specific hardware, high computational efficiency, superior measurement accuracy, and excellent adjustment performance, showing extremely high engineering application value. In addition, the measurement results of the present invention have good visualization effects, providing intuitive and reliable data support for engineering applications. Most importantly, the entire system does not need to rely on the theoretical model of the object being measured. It can automatically adjust the frequency disturbance amplitude that does not meet the safety requirements based on the actual system response and safety threshold. This intelligent adjustment mechanism based on theoretical support effectively avoids the situation of amplitude error modulation and ensures the reliability and accuracy of the measurement results.

[0131] Therefore, the present invention mainly has the following advantages:

[0132] First, the present invention is highly practical. The user only needs to specify the starting frequency, ending frequency, and number of frequency points to be measured. No special hardware equipment is required, and the user does not need to specify any other empirical parameters.

[0133] Second, the measurement is highly secure. The present invention uses the safe operation of the system as the judgment condition for amplitude adjustment, ensuring that the frequency response measurement process does not threaten the safety of the system.

[0134] Third, the measurement accuracy is high. The present invention uses nonlinear interpolation to process the measured data points, which can obtain a smooth curve that is closer to the true value. In addition, the setting of Chebyshev's non-equidistant measurement points avoids the occurrence of Runge's phenomenon, and the interpolation accuracy is much higher than that of linear interpolation.

[0135] Fourth, the amount of calculation is small. When adjusting the initial amplitude of the disturbance, the present invention adjusts the disturbance amplitude proportionally according to the response of the system, does not require complex calculation formulas, and has low time and space complexity.

[0136] Fifth, the adjustment performance is excellent. During the amplitude adjustment process, the present invention provides theoretical support for amplitude adjustment. There are no empirical parameters in the whole process, which avoids the occurrence of amplitude error modulation. In addition, the number of adjustments is small and the adjustment time is short.

[0137] Example 2:

[0138] The present invention based on the same inventive concept also provides a frequency response measurement system based on amplitude adaptive adjustment and nonlinear interpolation, the structural composition diagram is shown in FIG. Figure 8 As shown, including:

[0139] A disturbance determination module is used to determine the disturbance amplitude of the test frequency point based on each test frequency point of the object under test and according to the pre-calculated safe operation threshold information of the test frequency point;

[0140] The frequency perturbation module is used to perform frequency perturbation on the object under test according to the perturbation amplitude of the test frequency point to obtain the frequency response of the object under test at the test frequency point;

[0141] An amplitude correction module is used to correct the disturbance amplitude at the test frequency point based on the frequency response and safe operation threshold information of the object under test at the test frequency point, thereby obtaining the frequency characteristic data of the object under test at the test frequency point;

[0142] The result output module is used to output the frequency response characteristic curve of the measured object based on the frequency characteristic data of the measured object at each test frequency point using a nonlinear interpolation algorithm.

[0143] In one implementation, the frequency response measurement system may further include a disturbance determination module, specifically including:

[0144] The information acquisition submodule is used to obtain the operating information of the object under test in a steady-state condition at the test frequency point;

[0145] The threshold determination submodule is used to calculate the safe operation threshold information of the tested object at the test frequency point based on the operation information;

[0146] The operation information includes one or more of the following: voltage information and current information.

[0147] In one implementation, the frequency response measurement system may further include a frequency point generation module, specifically including:

[0148] The data acquisition submodule is used to obtain the starting test frequency, ending test frequency and number of test frequency points of the object under test;

[0149] A coordinate conversion submodule is used to perform logarithmic coordinate conversion on the starting test frequency and the ending test frequency;

[0150] The measurement point generation submodule is used to calculate the non-equidistant measurement points of the object under test using the Chebyshev method based on the number of test frequency points, the starting test frequency and the ending test frequency after coordinate conversion;

[0151] The frequency point output submodule is used to use the non-equidistant measurement points of the measured object as the test frequency points for frequency response measurement of the measured object.

[0152] In one implementation, the disturbance determination module may include:

[0153] The range calculation submodule is used to obtain the safe disturbance amplitude range of the test frequency point based on the pre-calculated safe operation threshold information of the test frequency point;

[0154] The amplitude setting submodule is used to determine the maximum value of the safe disturbance amplitude range as the disturbance amplitude of the test frequency point.

[0155] In one implementation, the frequency perturbation module may include:

[0156] The signal generation submodule is used to generate a disturbance signal at the test frequency point according to the disturbance amplitude at the test frequency point;

[0157] The frequency response submodule is used to perform frequency perturbation on the object under test according to the perturbation signal of the test frequency point to obtain the frequency response of the object under test at the test frequency point;

[0158] The frequency response includes one or more of the following: output signal amplitude, phase change, voltage change, and current change.

[0159] In one implementation, the amplitude correction module may include:

[0160] The safety judgment submodule is used to judge whether the disturbance amplitude meets the preset safety requirements based on the frequency response of the tested object at the test frequency point and the safety operation threshold information;

[0161] The characteristic output submodule is used to calculate the frequency characteristic data of the test frequency point according to the disturbance amplitude and frequency response of the test frequency point when the disturbance amplitude meets the preset safety requirements;

[0162] The dynamic correction submodule is used to correct the disturbance amplitude of the test frequency point according to the frequency response and safe operation threshold information of the test frequency point when the disturbance amplitude does not meet the preset safety requirements, and calculate the frequency characteristic data of the test frequency point based on the corrected disturbance amplitude.

[0163] In this implementation, the above-mentioned dynamic correction submodule may include:

[0164] A coefficient calculation unit is used to calculate the proportional adjustment coefficient of the disturbance amplitude according to the frequency response of the test frequency point and the safe operation threshold information;

[0165] A correction unit, configured to correct the disturbance amplitude according to a proportional adjustment coefficient of the disturbance amplitude;

[0166] The characteristic calculation unit is used to calculate the frequency characteristic data of the object under test at the test frequency point when the corrected disturbance amplitude meets the safety requirements.

[0167] Example 3:

[0168] like Figure 9 As shown, the present invention also provides an electronic device, which may be a computer, a single-chip microcomputer, a smart mobile device, or the like. The electronic device in this embodiment may include a processor, a memory, a transceiver component, and the like. The memory, processor, and transceiver component are connected via a bus; the memory may be used to store an execution program, which may include instructions; and the processor may be used to execute the instructions stored in the memory. The memory may also be used to store data, which may be accessed and / or modified during the execution of the instructions.

[0169] The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in a storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation in the above-mentioned embodiment.

[0170] Example 4:

[0171] Based on the same inventive concept, the present invention also provides a readable storage medium, specifically an electronic device readable storage medium (Memory), which is a memory device in an electronic device for storing programs and data. It is understandable that the storage medium here can include both built-in storage media in the electronic device and, of course, extended storage media supported by the electronic device. The storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more execution programs (including program codes). It should be noted that the storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor loads and executes one or more instructions stored in the storage medium, which can implement the steps of a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation in the above embodiment.

[0172] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0173] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0174] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1The function specified in one or more boxes.

[0175] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0176] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art may still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims.

Claims

1. A frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation, characterized in that: include: Based on each test frequency point of the measured object, determining the disturbance amplitude of the test frequency point according to pre-calculated safe operation threshold information of the test frequency point; Performing frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point to obtain a frequency response of the object under test at the test frequency point; Based on the frequency response of the measured object at the test frequency point and the safe operation threshold information, the disturbance amplitude of the test frequency point is corrected to obtain the frequency characteristic data of the measured object at the test frequency point; According to the frequency characteristic data of the measured object at each test frequency point, a frequency response characteristic curve of the measured object is outputted using a nonlinear interpolation algorithm.

2. The method according to claim 1, wherein The correcting the disturbance amplitude of the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information to obtain the frequency characteristic data of the measured object at the test frequency point includes: Determining whether the disturbance amplitude meets a preset safety requirement based on the frequency response of the measured object at the test frequency point and the safe operation threshold information; If satisfied, calculate the frequency characteristic data of the test frequency point according to the disturbance amplitude and frequency response of the test frequency point; If not, the disturbance amplitude of the test frequency point is corrected according to the frequency response of the test frequency point and the safe operation threshold information, and the frequency characteristic data of the test frequency point is calculated according to the corrected disturbance amplitude.

3. The method according to claim 2, wherein The step of correcting the disturbance amplitude of the test frequency point according to the frequency response and safe operation threshold information of the test frequency point, and calculating the frequency characteristic data of the test frequency point according to the corrected disturbance amplitude, includes: Calculating a proportional adjustment coefficient of the disturbance amplitude based on the frequency response of the test frequency point and the safe operation threshold information; Correcting the disturbance amplitude according to a proportional adjustment coefficient of the disturbance amplitude; When the corrected disturbance amplitude meets the safety requirement, the frequency characteristic data of the measured object at the test frequency point is calculated.

4. The method according to claim 1, wherein The safe operation threshold information of the test frequency point includes the following calculation process: Obtaining operating information of the object under test in a steady-state condition at the test frequency point; Calculating the safe operation threshold information of the measured object at the test frequency point according to the operation information; The operation information includes one or more of the following: voltage information and current information.

5. The method according to claim 1 or 4, wherein: The determining the disturbance amplitude of the test frequency point according to the pre-calculated safe operation threshold information of the test frequency point includes: Obtaining a safe disturbance amplitude range for the test frequency point based on pre-calculated safe operation threshold information for the test frequency point; The maximum value of the safe disturbance amplitude range is determined as the disturbance amplitude of the test frequency point.

6. The method according to claim 1, wherein The performing frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point to obtain a frequency response of the object under test at the test frequency point includes: generating a disturbance signal at the test frequency point according to the disturbance amplitude at the test frequency point; Performing frequency perturbation on the object under test according to the disturbance signal at the test frequency point to obtain a frequency response of the object under test at the test frequency point; The frequency response includes one or more of the following: output signal amplitude, phase change, voltage change and current change.

7. The method according to claim 1, wherein Before determining the disturbance amplitude of each test frequency point based on each test frequency point of the measured object according to pre-calculated safe operation threshold information of the test frequency point, the method further includes: Obtain the starting test frequency, ending test frequency and number of test frequency points of the object under test; Performing logarithmic coordinate conversion on the starting test frequency and the ending test frequency; Calculating the non-equidistant measurement points of the object under test using the Chebyshev method based on the number of test frequency points, the starting test frequency and the ending test frequency after coordinate conversion; The non-equidistant measurement points of the measured object are used as test frequency points for frequency response measurement of the measured object.

8. A frequency response measurement system based on amplitude adaptive adjustment and nonlinear interpolation, characterized in that: include: A disturbance determination module is configured to determine, based on each test frequency point of the measured object and according to pre-calculated safe operation threshold information of the test frequency point, a disturbance amplitude of the test frequency point; A frequency perturbation module, configured to perform frequency perturbation on the object under test according to the perturbation amplitude at the test frequency point, so as to obtain a frequency response of the object under test at the test frequency point; an amplitude correction module, configured to correct the disturbance amplitude of the test frequency point based on the frequency response of the measured object at the test frequency point and the safe operation threshold information, and obtain frequency characteristic data of the measured object at the test frequency point; The result output module is used to output the frequency response characteristic curve of the measured object by using a nonlinear interpolation algorithm according to the frequency characteristic data of the measured object at each test frequency point.

9. An electronic device, characterized in that: include: at least one processor and memory; The memory and the processor are connected via a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, the frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation according to any one of claims 1 to 7 is implemented.

10. A computing device readable storage medium, characterized in that: An execution program is stored thereon, and when the execution program is executed, a frequency response measurement method based on amplitude adaptive adjustment and nonlinear interpolation as claimed in any one of claims 1 to 7 is implemented.

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