A multiplier method for removing amplitude-frequency variation interference and analyzing broadband dense frequency signals, a system and a storage medium

Abstract

The present invention provides a multiplier method for removing amplitude-frequency variation interference, a broadband dense frequency signal analysis method, a system and a storage medium. The method comprises: S1, signal sampling and conversion: the power signal x(t) is sampled and converted by f s Sampling is performed at the sampling frequency, and the sampled signal is subjected to a Taylor-Fourier transform to obtain a sample phasor x; S2, defining amplitude-frequency variation interference: introducing an interference operator τ; S3, quantifying the amplitude-frequency variation interference: iteratively calculating the Jacobian determinant of τ for the composite mapping #imgabs0# of the sample phasor x and the interference operator τ; S4, removing the amplitude-frequency variation interference: iteratively calculating the interference operator; S5, iterating using the multiplier method: iteratively solving for parameters ε and p containing the amplitude-frequency characteristics of the original signal, thereby completing the analysis of the broadband dense frequency signal. The present invention suppresses the interference of the power signal's amplitude-frequency variation interference on the sampling signal analysis process by quantitatively calculating the power signal's amplitude-frequency variation interference, thereby achieving accurate analysis of the broadband dense frequency signal.

Description

Technical Field

[0001] The present invention relates to the field of power quality detection and analysis, and in particular to a broadband dense frequency signal analysis method, system and storage medium using a multiplier method for removing amplitude-frequency variation interference. Technical Background

[0002] As various power electronic devices are connected to the power grid, harmonics and interharmonics seriously affect the safe and stable operation of the power system. Therefore, quickly and accurately analyzing the signals of harmonic and interharmonic components in the power system is of great significance for improving power quality.

[0003] Currently, there are two main methods for detecting harmonic and interharmonic phasors: discrete Fourier transform (DFT)-based methods and non-DFT methods. These include window function methods, anti-leakage Fourier transform methods, interpolation methods, and harmonic phasor estimators. While these methods can reduce spectral leakage and picket fence effects, they can suffer from significant errors when processing densely packed frequency signals. Therefore, achieving accurate measurement of broadband, densely packed signals while maintaining computational speed remains a current technical challenge. Summary of the Invention

[0004] The purpose of the present invention is to propose a broadband intensive frequency signal analysis method system and storage medium using a multiplier method for removing amplitude-frequency variation interference. The multiplier method for removing amplitude-frequency variation interference is capable of suppressing the influence of dynamic amplitude-frequency variation before analyzing broadband intensive frequency signals of a power system. By quantitatively calculating the amplitude-frequency variation interference of a power signal, the interference of the amplitude-frequency variation interference on the sampling signal analysis process is suppressed, thereby achieving accurate analysis of broadband intensive frequency signals and greatly improving the accuracy of signal analysis.

[0005] The present invention is implemented by the following technical solutions:

[0006] A broadband dense frequency signal analysis method using a multiplier method for removing amplitude-frequency variation interference comprises the following steps:

[0007] S1. Signal sampling and transformation: The power signal x(t) is converted to f s Sampling is performed at the sampling frequency, and Taylor Fourier transform is performed on the sampled signal to obtain the sample phasor x;

[0008] S2. Define amplitude-frequency interference: Considering the dynamic changes of the amplitude and frequency of the actual signal, the interference operator τ is introduced, and the sample phase x is converted to xοτ=Bp+ε, where B is N×2(M k +1)K-order low-rank matrix, p is a length of 2(M k +1)K is the amplitude-frequency characteristic phasor, ε is the noise phasor with a length of K;

[0009] S3. Quantifying the amplitude-frequency variation interference: performing iterative calculation of the Jacobian determinant of the composite mapping xοτ of the sample phasor x and the interference operator τ with respect to τ to obtain the basic conditions for iterative calculation of the interference operator;

[0010] S4. Remove the amplitude-frequency variation interference: Iterate the interference operator τ in the formula xοτ=Bp+ε obtained in S2 to remove the influence of the amplitude-frequency variation interference on the original signal measurement;

[0011] S5. Multiplier method iteration: The parameter noise phasor ε and the amplitude-frequency characteristic phasor p in xοτ=Bp+ε are solved iteratively by the multiplier method, thereby completing the analysis of the broadband dense frequency signal.

[0012] Furthermore, the specific implementation process of S1 includes:

[0013] For a dense frequency signal x(t) containing K components, s Sampling is performed at the sampling frequency, and Taylor Fourier transform is performed on the sampled signal to obtain the N×1 order sample phasor x:

[0014] x=Bp

[0015] Among them, B is N×2(M k +1)K-order low-rank matrix, M k is the maximum order of Taylor Fourier transform of the kth signal component, K is the number of signal components, and p is the length of 2 (M k +1)K's phasor.

[0016] Furthermore, in S3:

[0017] The Jacobian determinant of the composite mapping of x and τ with respect to τ is iteratively calculated and defined as follows:

[0018]

[0019] Among them, xοτ i Denote x and τ i The composite mapping, i represents the number of iterations of the interference operator, ~ represents the estimated value, τ i represents the calculated value of the interference operator τ after the i-th iteration, represents the Jacobian determinant.

[0020] Furthermore, the specific implementation process of S4 includes:

[0021] By linearization To iteratively solve, the convergence value of the interference operator is obtained, thereby removing the influence of amplitude-frequency variation interference on the original signal measurement. The interference operator iteration is defined as follows:

[0022]

[0023] Where Δτ i represents the change of the interference operator during the iteration process, It represents the estimated value after substituting the calculated value of the interference operator after the i-th iteration into the original signal, Denotes the Jacobian determinant of the composite mapping xοτ of the sample phasor x and the interference operator τ with respect to τ, B i Represents the low-rank matrix B calculated after the i-th iteration.

[0024] Furthermore, in said S5:

[0025] The parameters ε and p containing the amplitude-frequency characteristics of the original signal are solved iteratively by the multiplier method. The phasor v is introduced to simplify the expression. The multiplier method iteration is defined as follows:

[0026]

[0027] Where k represents the number of iterations of the multiplier method.

[0028] A multiplier method broadband dense frequency signal analysis system for removing amplitude-frequency variation interference, comprising: a computer-readable storage medium and a processor;

[0029] The computer-readable storage medium is used to store executable instructions;

[0030] The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference.

[0031] A non-transitory computer-readable storage medium stores a computer program, which, when executed by a processor, implements the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference.

[0032] The advantage of the present invention is that by introducing an interference operator, the influence of dynamic changes in amplitude and frequency of the original power signal during the sampling process is quantified, and the influence of interference can be quickly eliminated. Finally, through the iteration of the multiplier method, the amplitude-frequency data of the sampled signal is obtained, and the analysis of the broadband dense frequency signal is finally completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The step change test results of the present invention, where (a) is the response time when TVE reaches 2%; (b) is the response time when FE reaches 0.14 Hz; (c) is the response time when RFE reaches 1.6 Hz / s;

[0034] Figure 2The figure is a flow chart of one embodiment of a broadband dense frequency signal analysis method using a multiplier method for removing amplitude-frequency variation interference according to the present invention. DETAILED DESCRIPTION

[0035] To further illustrate the technical solution of the present invention, the following will be combined with the accompanying drawings and embodiments to make the content of the present invention clearer. It should be noted that the combined embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] In order to highlight the analytical effect of the algorithm, this embodiment selects the discrete Fourier transform (DFT) method, the Sinc method, the harmonic phasor estimator (HPE) and the standard basis pursuit denoising (BPDN) method as the comparison algorithms of the algorithm (RIM) proposed in this invention. Assume that the sampling rate is 10kHz and the sampling window length is set to 10 power frequency cycles. The total vector error (TVE), absolute frequency error (FE) and absolute frequency rate error (RFE) defined in the IEEE C37.118.1a-2014 standard are used to evaluate the algorithm performance. The test signals selected in this implementation are as follows:

[0037]

[0038] Among them, L represents the total number of low-frequency harmonic components, l is the serial number of the low-frequency harmonic component, H represents the total number of high-frequency harmonic components, h is the serial number of the high-frequency harmonic component, A l Indicates the amplitude of the lth harmonic component in the low frequency band, f l represents the frequency of the lth harmonic component in the low frequency band, t represents time, A h Indicates the amplitude of the hth harmonic component in the high frequency band, f h Indicates the frequency of the hth harmonic component in the low frequency band. At t = 2s, the amplitude and phase of each frequency component change to 110% and π / 18 of the original amplitude and phase respectively. The final test results are as follows Figure 1 shown.

[0039] See also Figure 2 The embodiment of the present invention provides a broadband dense frequency signal analysis method using a multiplier method for removing amplitude-frequency variation interference, comprising the following steps:

[0040] S1. Signal sampling and transformation: The power signal x(t) is converted to f s The sampling frequency is sampled, and the sampled signal is subjected to Taylor Fourier transform to obtain the sample phasor x.

[0041] Specifically, for a dense frequency signal x(t) containing K components, sSampling is performed at the sampling frequency, and Taylor Fourier transform is performed on the sampled signal to obtain the N×1 order sample phasor x:

[0042] x=Bp

[0043] Among them, B is N×2(M k +1)K-order low-rank matrix, M k is the maximum order of Taylor Fourier transform of the kth signal component, K is the number of signal components, and p is the length of 2 (M k +1)K's phasor.

[0044] S2. Definition of amplitude-frequency interference: Considering that the amplitude and frequency of the actual signal change dynamically due to the influence of sampling error, the interference operator τ is introduced, and the sample phase x is converted to xοτ=Bp+ε, where B is N×2(M k +1)K-order low-rank matrix, p is a length of 2(M k +1)K’s amplitude-frequency characteristic phasor.

[0045] S3. Quantifying the amplitude-frequency interference: Perform an iterative calculation of the Jacobian determinant of the composite mapping xοτ of the sample phasor x and the interference operator τ with respect to τ to obtain the basic conditions for the iterative calculation of the interference operator. Specifically, the iterative calculation of the Jacobian determinant of the composite mapping xοτ with respect to τ is defined as follows:

[0046]

[0047] Among them, xοτ i Denote x and τ i The composite mapping, i represents the number of iterations of the interference operator, ~ represents the estimated value, τ i represents the calculated value of the interference operator τ after the i-th iteration, represents the Jacobian determinant.

[0048] S4. Removing the Amplitude-Frequency Variation Interference: Perform iterative calculation on the interference operator τ in the formula xοτ=Bp+ε obtained in S2, thereby removing the influence of the amplitude-frequency variation interference on the original signal measurement.

[0049] Specifically, by linearization To iteratively solve, the convergence value of the interference operator is obtained, thereby removing the influence of amplitude-frequency variation interference on the original signal measurement. The interference operator iteration is defined as follows:

[0050]

[0051] Where Δτ i represents the change of the interference operator during the iteration process, It represents the estimated value after substituting the calculated value of the interference operator after the i-th iteration into the original signal, Denotes the Jacobian determinant of the composite mapping xοτ of the sample phasor x and the interference operator τ with respect to τ, B i Represents the low-rank matrix B calculated after the i-th iteration.

[0052] S5. Multiplier method iteration: The parameter noise phasor ε and the amplitude-frequency characteristic phasor p in xοτ=Bp+ε are solved iteratively by the multiplier method, thereby completing the analysis of the broadband dense frequency signal.

[0053] Specifically, the parameters ε and p containing the amplitude-frequency characteristics of the original signal are iteratively solved by the multiplier method. To simplify the expression, the phasor v is introduced. The multiplier method iteration is defined as follows:

[0054]

[0055] Where k represents the number of iterations of the multiplier method.

[0056] The final test results are as follows Figure 1 As shown, the analysis accuracy in step change test is improved by about 30% compared with the existing technology.

[0057] An embodiment of the present invention further provides a multiplier method broadband dense frequency signal analysis system for removing amplitude-frequency variation interference, comprising: a computer-readable storage medium and a processor;

[0058] The computer-readable storage medium is used to store executable instructions;

[0059] The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference.

[0060] An embodiment of the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference is implemented.

[0061] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt 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.) that contain computer-usable program code.

[0062] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, 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 steps in the process. 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.

[0063] 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 1 The function specified in one or more boxes.

[0064] 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 The steps for the function specified in one or more boxes.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A broadband dense frequency signal analysis method using a multiplier method for removing amplitude-frequency variation interference, characterized in that: The following steps are involved: S1. Signal sampling and transformation: The power signal x(t) is converted to f s Sampling is performed at the sampling frequency, and Taylor Fourier transform is performed on the sampled signal to obtain the sample phasor x; S2. Define amplitude-frequency interference: Considering the dynamic changes of the amplitude and frequency of the actual signal, the interference operator τ is introduced and the sample phase x is converted to , where B is Low-rank matrix, p is a length of The amplitude-frequency characteristic phasor of is the noise phasor of length K; S3. Quantized amplitude-frequency interference: composite mapping of sample phasor x and interference operator τ Perform iterative calculation of the Jacobian determinant of τ to obtain the basic conditions for iterative calculation of the interference operator; S4, remove the interference of amplitude-frequency variation: The interference operator τ in is iteratively calculated to remove the influence of amplitude-frequency variation interference on the original signal measurement; S5. Multiplier method iteration: Solve by multiplier method iteration The parameter noise phasor in , amplitude-frequency characteristic phasor p, thereby completing the analysis of broadband and dense frequency signals; In the S3: The Jacobian determinant of the composite mapping of x and τ with respect to τ is iteratively calculated and defined as follows: ； in, represents x and The composite mapping, i represents the number of iterations of the interference operator, ~ represents the estimated value, Interference operator The calculated value after the i-th iteration, represents the Jacobian determinant; The specific implementation process of S4 includes: By linearization To iteratively solve, the convergence value of the interference operator is obtained, thereby removing the influence of amplitude-frequency variation interference on the original signal measurement. The interference operator iteration is defined as follows: ， ； in, represents the change of the interference operator during the iteration process, It represents the estimated value after substituting the calculated value of the interference operator after the i-th iteration into the original signal, Represents the composite mapping of sample phasor x and interference operator τ The Jacobian determinant of τ is, Represents the low-rank matrix B calculated after the i-th iteration.

2. The method for analyzing broadband dense frequency signals using a multiplier method for removing amplitude-frequency variation interference according to claim 1, characterized in that: The specific implementation process of S1 includes: For a dense frequency signal x(t) containing K components, Sampling is performed at the sampling frequency, and Taylor Fourier transform is performed on the sampled signal to obtain Order sample phasor x: ； Among them, B is low-rank matrix, is the maximum order of Taylor Fourier transform of the kth signal component, K is the number of signal components, and p is the length of phasor.

3. The method for analyzing broadband dense frequency signals using a multiplier method for removing amplitude-frequency variation interference according to claim 1, characterized in that: In said S5: Iteratively solve the parameters containing the amplitude-frequency characteristics of the original signal through the multiplier method , p, the phasor v is introduced to simplify the expression, and the multiplier method iteration is defined as follows: ； Where k represents the number of iterations of the multiplier method.

4. A broadband dense frequency signal analysis system using a multiplier method for removing amplitude-frequency variation interference, characterized in that: include: Computer-readable storage medium and processor; The computer-readable storage medium is used to store executable instructions; The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference according to any one of claims 1 to 3.

5. A non-transitory computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the multiplier method broadband dense frequency signal analysis method for removing amplitude-frequency variation interference according to any one of claims 1 to 3 is implemented.

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