A method for measuring mutual inductance parameters of a same-tower double-circuit transmission line and related equipment

Abstract

The present application belongs to the technical field of power transmission line, discloses a kind of measurement method and related equipment of mutual inductance parameter of same-tower double-circuit transmission line, steps are as follows: S1, in same-tower double-circuit line, keep first return live operation, second return is shut down and end three-phase short-circuit ground, inject target off power frequency frequency current signal at the first end of second return;S2, synchronously collect first return line first end and end zero sequence voltage signal, determine first end and end zero sequence voltage drop waveform;S3, utilize five Rife-Vincent windows and four spectrum line interpolation algorithm analysis first end and end zero sequence voltage drop waveform spectrum, obtain spectrum table;S4, whether the side lobe level of spectrum table is less than preset value, if not, optimization weighted coefficient and repeat S3, S4;If yes, execute S5;S5, extract zero sequence induced voltage amplitude under target off frequency, calculate mutual inductance parameter in combination with target off frequency current signal amplitude, realize same-tower double-circuit line zero sequence mutual inductance parameter accurate extraction.

Description

Technical Field

[0001] This invention belongs to the field of power transmission line technology, specifically relating to a method and related equipment for measuring mutual inductance parameters of a double-circuit power transmission line on the same tower. Background Technology

[0002] In the design and operation research of double-circuit transmission lines on the same tower, accurate measurement of positive-sequence and zero-sequence mutual inductance parameters is a fundamental prerequisite for determining the phase-to-phase coupling characteristics of the line. Understanding these coupling characteristics is crucial for power flow calculation, fault analysis, and relay protection settings. Specifically, whether the relay protection device's settings based on these parameters accurately reflect the actual electromagnetic coupling condition of the line directly affects the selectivity, speed, and sensitivity of the protection device when a fault occurs. This ensures that the protection device can reliably identify the faulty circuit and quickly and selectively disconnect the faulty section, thereby maintaining the stable operation of the power system and becoming a key foundation for supporting the reliability of the power grid.

[0003] Currently, the measurement of mutual inductance parameters in double-circuit transmission lines on the same tower mainly employs the heterodyne method combined with Fast Fourier Transform (FFT) technology. This involves applying heterodyne signals to perform precise frequency domain analysis and feature extraction on the signals acquired by the substation recording device. However, existing FFT algorithms cannot address issues such as spectral leakage, sidelobe interference, and the picket fence effect. Spectral leakage stems from the truncation effect of asynchronous sampling, causing signal energy to diffuse from the dominant frequency to adjacent frequencies. This results in target harmonic amplitude errors of up to 5%, and a frequency offset exceeding 0.1Hz triggers phase synchronization failure. Sidelobe interference, due to insufficient sidelobe attenuation of the window function (e.g., a rectangular window sidelobe of only -13dB), causes strong signal sidelobes to overwhelm adjacent weak components. For example, strong power frequency interference from the transmission line itself generates significant interference to near-power frequency target signals, affecting the accurate extraction of the target signal amplitude. The picket fence effect, caused by discrete frequency sampling, forces the true spectral peak to fall within the frequency "fence," resulting in an amplitude underestimation of 3%-10% compared to the true value, constituting a systematic deviation in the accuracy of power metering and harmonic analysis. In summary, existing FFT-based traditional inter-frequency mutual inductance parameter measurement methods struggle to accurately extract zero-sequence mutual inductance parameters for dual-circuit lines on the same tower. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a method and related equipment for measuring the mutual inductance parameters of a double-circuit transmission line on the same tower, with the aim of accurately extracting the zero-sequence mutual inductance parameters of the double-circuit transmission line on the same tower.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] According to a first aspect of the present invention, a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower is provided, comprising:

[0007] S1. In a double-circuit transmission line on the same tower, keep the first circuit energized and operate the second circuit, shut down the second circuit and short-circuit the three phases at the end to ground, and inject a target frequency current signal that deviates from the power frequency at the beginning of the second circuit.

[0008] S2. Synchronously acquire the zero-sequence voltage signals at the beginning and end of the first circuit, and determine the zero-sequence voltage drop waveform at the beginning and end of the first circuit based on the zero-sequence voltage signals at the beginning and end.

[0009] S3. Perform spectral analysis on the zero-sequence voltage drop waveform at the beginning and end using a five-term Rife-Vincent window and a four-line interpolation algorithm to obtain the spectral table of the zero-sequence voltage drop waveform at the beginning and end.

[0010] S4. Determine whether the sidelobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end is less than the preset sidelobe level gain amplitude. If it is not less than the preset sidelobe level gain amplitude, optimize the weighting coefficients of the five Rife-Vincent windows and repeat S3 and S4. If it is less than the preset sidelobe level gain amplitude, execute S5.

[0011] S5. Extract the amplitude of the zero-sequence induced voltage at the target frequency from the zero-sequence voltage drop waveform spectrum table at the beginning and end. Calculate the mutual inductance parameters of the double-circuit transmission line on the same tower based on the amplitude of the target frequency current signal and the amplitude of the zero-sequence induced voltage at the target frequency.

[0012] In one possible implementation of the first aspect, the spectral analysis of the zero-sequence voltage drop waveform at the beginning and end is performed using a five-term Rife-Vincent window and a four-line interpolation algorithm to obtain a spectral table of the zero-sequence voltage drop waveform at the beginning and end, specifically as follows:

[0013] A five-term Rife-Vincent window is added to the zero-sequence voltage drop waveform at both ends;

[0014] A fast Fourier transform is performed on the zero-sequence voltage drop waveform at the beginning and end after applying a five-term Rife-Vincent window to obtain the initial zero-sequence voltage drop waveform spectrum table.

[0015] The initial zero-sequence voltage drop waveform spectrum table at the beginning and end is corrected by using a four-line interpolation algorithm to obtain the zero-sequence voltage drop waveform spectrum table at the beginning and end.

[0016] In one possible implementation of the first aspect, the optimization of the weighting coefficients of the five Rife-Vincent windows specifically involves:

[0017] The weighting coefficients of the five Rife-Vincent windows are optimized using Newton's method or gradient descent method.

[0018] In one possible implementation of the first aspect, when optimizing the weighting coefficients of the five Rife-Vincent windows, the following must be satisfied:

[0019] The main lobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end does not exceed the preset main lobe level gain amplitude, and the weighting coefficients of the five Rife-Vincent windows are forced to be symmetrical.

[0020] In one possible implementation of the first aspect, extracting the zero-sequence induced voltage amplitude at the target different frequency from the zero-sequence voltage drop waveform spectrum table at the beginning and end specifically involves:

[0021] Using the target frequency as an index, traverse the spectrum table of the zero-sequence voltage drop waveform at the beginning and end to obtain the amplitude of the zero-sequence induced voltage at the target frequency.

[0022] In one possible implementation of the first aspect, the calculation of the mutual inductance parameters of the double-circuit transmission line on the same tower based on the amplitude of the target inter-frequency current signal and the amplitude of the zero-sequence induced voltage at the target inter-frequency is specifically as follows:

[0023]

[0024] In the formula, For mutual inductance parameters of a double-circuit transmission line on the same tower; The zero-sequence induced voltage amplitude at the target frequency; The amplitude of the frequency-differential current in the first circuit under the target frequency; The amplitude of the frequency-differential current in the second circuit under the target frequency; For complex units; The angular frequency of the target different frequency; The resistance between the beginning and end of the first circuit; This refers to the inductance between the beginning and end of the first circuit.

[0025] In one possible implementation of the first aspect, the heterogeneous current signal is a current signal deviating from the power frequency by ±10Hz.

[0026] According to a second aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower.

[0027] According to a third aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower.

[0028] According to a fourth aspect of the present invention, a computer program product is provided, which, when executed by a processor, implements the method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower.

[0029] Compared with the prior art, the present invention has at least the following beneficial effects:

[0030] This invention provides a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower. It employs a five-term Rife-Vincent(I) window combined with a four-spectral-line interpolation algorithm. The five-term Rife-Vincent(I) window exhibits excellent spectral energy diffusion suppression performance, concentrating the energy of the target inter-frequency zero-sequence voltage signal closer to its true frequency, reducing interference from adjacent frequency components (especially strong power frequency harmonics), effectively solving the spectral leakage problem, avoiding large amplitude errors in the target harmonics, and improving the accuracy of signal analysis. The four-spectral-line interpolation algorithm does not rely on the signal frequency falling exactly at the FFT frequency point; instead, it utilizes the amplitude relationship of four spectral lines near the target frequency to accurately calculate the frequency offset, thereby improving the estimation accuracy of frequency, amplitude, and phase, and overcoming the picket fence effect. By iteratively optimizing the weighting coefficients of the five-term Rife-Vincent(I) window, it can achieve good adaptation to zero-sequence induced voltage waveforms under different inter-frequency operating conditions, thereby improving the suppression capability of spectral sidelobes under complex operating conditions, reducing interference from strong signal sidelobes to weak signals, and ensuring accurate extraction of the target inter-frequency signal amplitude. By combining the above effective solutions to spectral leakage, picket fence effect, and spectral sidelobes, this invention can effectively improve the accuracy of measuring zero-sequence mutual inductance parameters of double-circuit lines on the same tower, and solves the problem of difficulty in accurately extracting zero-sequence mutual inductance parameters of double-circuit lines on the same tower in the prior art.

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a flowchart illustrating a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower, as described in an embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] like Figure 1 As shown, an embodiment of the present invention provides a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower, which specifically includes the following steps:

[0036] S1. In a double-circuit transmission line on the same tower, keep the first circuit energized and shut down the second circuit and short-circuit the three phases at the end to ground. Inject a target frequency current signal that deviates from the power frequency at the beginning of the second circuit.

[0037] Specifically, the first circuit is kept energized with the load-side current at its rated value; the second circuit is shut down and its three phases are short-circuited to ground at its end. A target frequency current signal is injected at the beginning of the second circuit using a frequency-controlled current source. In this embodiment, the frequency-controlled current signal is a current signal deviating from the power frequency by ±10Hz. For example, the target frequency-controlled current signal deviates from the power frequency by ±2.5Hz, i.e., the target frequency is 47.5Hz (or 52.5Hz), with an amplitude of 10A. The frequency-controlled current source uses a programmable current source with a frequency resolution of 0.01Hz and an amplitude stability of ±0.1%.

[0038] S2. Synchronously acquire the zero-sequence voltage signals at the beginning and end of the first circuit, and determine the zero-sequence voltage drop waveform at the beginning and end of the first circuit based on the zero-sequence voltage signals at the beginning and end.

[0039] Specifically, voltage transformers are used to synchronously acquire the zero-sequence voltage signals at the beginning (substation side) and end (middle section) of the first circuit. The sampling frequency is set to 10kHz to satisfy the Nyquist sampling theorem, and the sampling duration is 1s (including 10 different frequency signal cycles). Differential calculations are performed on the zero-sequence voltage signals at the beginning and end to obtain the zero-sequence voltage drop waveforms at both ends:

[0040] Δ U 0( t )= U 0, beginning ( t )- U 0, terminal ( t )

[0041] in, U 0, beginning ( t )and U 0, terminal ( t ) are the instantaneous zero-sequence voltage values ​​at the beginning and end of the circuit, respectively.

[0042] S3. Perform spectral analysis on the zero-sequence voltage drop waveform at the beginning and end using a five-term Rife-Vincent window and a four-line interpolation algorithm to obtain the spectral table of the zero-sequence voltage drop waveform at the beginning and end.

[0043] In one feasible approach, the spectral analysis of the zero-sequence voltage drop waveform at both ends is performed using a five-term Rife-Vincent window and a four-line interpolation algorithm to obtain a spectral table of the zero-sequence voltage drop waveform at both ends, as detailed below:

[0044] First, a five-term Rife-Vincent window is added to the zero-sequence voltage drop waveform at both ends.

[0045] Specifically, the time-domain expression of the five Rife-Vincent windows:

[0046]

[0047] in, For window functions; N Window length (number of sampling points); The sampling point number; These are the weighting coefficients.

[0048] Next, a fast Fourier transform is performed on the zero-sequence voltage drop waveform at the beginning and end after adding five Rife-Vincent windows to obtain the spectrum table of the initial zero-sequence voltage drop waveform at the beginning and end.

[0049] Finally, the initial zero-sequence voltage drop waveform spectrum table at the beginning and end is corrected using the four-line interpolation algorithm to obtain the zero-sequence voltage drop waveform spectrum table at the beginning and end.

[0050] Specifically, the peak values ​​of the spectrum are searched near the target frequency (47.5Hz or 52.5Hz) to determine the four spectral lines with the largest amplitude in the main lobe; the frequency offset is calculated by fitting a quadratic polynomial using the amplitude relationship of the four spectral lines; the amplitude of the main lobe spectral lines is interpolated and corrected according to the frequency offset to obtain the corrected spectrum table, which is the spectrum table of the zero-sequence voltage drop waveform at the beginning and end.

[0051] S4. Determine whether the sidelobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end is less than the preset sidelobe level gain amplitude. If it is not less than the preset value, optimize the weighting coefficients of the five Rife-Vincent windows and repeat S3 and S4. If it is less than the preset value, execute S5.

[0052] For example, the preset sidelobe level gain amplitude is -80dB. That is, if the sidelobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end is not less than -80dB, then weighted coefficient optimization is started, and steps S3 and S4 are re-executed using the optimized weighted coefficients until the sidelobe level requirement is met, and then the process jumps to step S5.

[0053] In one possible implementation, the optimization of the weighting coefficients of the five Rife-Vincent windows is as follows:

[0054] The weighting coefficients of the five Rife-Vincent windows are optimized using Newton's method or gradient descent method.

[0055] Preferably, when optimizing the weighting coefficients of the five Rife-Vincent windows, the following conditions must be met: the main lobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end does not exceed the preset main lobe level gain amplitude, and the weighting coefficients of the five Rife-Vincent windows are forced to be symmetrical.

[0056] For example, the preset main lobe level gain amplitude is -3dB. That is, when optimizing the weighting coefficients of the five Rife-Vincent windows, the main lobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end does not exceed -3dB and the weighting coefficients are symmetrical. = ).

[0057] S5. Extract the amplitude of the zero-sequence induced voltage at the target frequency from the zero-sequence voltage drop waveform spectrum table at the beginning and end. Calculate the mutual inductance parameters of the double-circuit transmission line on the same tower based on the amplitude of the target frequency current signal and the amplitude of the zero-sequence induced voltage at the target frequency.

[0058] In other words, by using the target frequency as an index, the zero-sequence voltage drop waveform spectrum table at the beginning and end is traversed to obtain the zero-sequence induced voltage amplitude at the target frequency.

[0059] In one feasible approach, the mutual inductance parameters of a double-circuit transmission line on the same tower are calculated based on the amplitude of the target frequency current signal and the amplitude of the zero-sequence induced voltage at the target frequency. Specifically:

[0060]

[0061] In the formula, For mutual inductance parameters of a double-circuit transmission line on the same tower; The zero-sequence induced voltage amplitude at the target frequency; The amplitude of the frequency-differential current in the first circuit under the target frequency; The amplitude of the frequency-differential current in the second circuit under the target frequency; For complex units; The angular frequency of the target different frequency; The resistance between the beginning and end of the first circuit; This refers to the inductance between the beginning and end of the first circuit. It should be understood that... and This was found in the line parameter manual.

[0062] In another embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used for the operation of a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower.

[0063] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the operating system of the terminal. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be Random Access Memory (RAM) or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower in the above embodiments.

[0064] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, etc.) containing computer-usable program code.

[0065] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations 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, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0066] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0067] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0068] This invention also provides a computer program product, which is used to execute any of the above-described methods for measuring the mutual inductance parameters of a double-circuit transmission line on the same tower. Since the computer program product provided by this invention and the above-described method for measuring the mutual inductance parameters of a double-circuit transmission line on the same tower belong to the same inventive concept, the computer program product provided by this invention has all the advantages of the above-described method for measuring the mutual inductance parameters of a double-circuit transmission line on the same tower. Therefore, the beneficial effects of the computer program product provided by this invention will not be elaborated further here.

[0069] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0070] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the scope of the technology disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention.

Claims

1. A method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower, characterized in that, include: S1. In a double-circuit transmission line on the same tower, keep the first circuit energized and operate the second circuit, shut down the second circuit and short-circuit the three phases at the end to ground, and inject a target frequency current signal that deviates from the power frequency at the beginning of the second circuit. S2. Synchronously acquire the zero-sequence voltage signals at the beginning and end of the first circuit, and determine the zero-sequence voltage drop waveform at the beginning and end of the first circuit based on the zero-sequence voltage signals at the beginning and end. S3. Perform spectral analysis on the zero-sequence voltage drop waveform at the beginning and end using a five-term Rife-Vincent window and a four-line interpolation algorithm to obtain the spectral table of the zero-sequence voltage drop waveform at the beginning and end. S4. Determine whether the sidelobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end is less than the preset sidelobe level gain amplitude. If it is not less than the preset sidelobe level gain amplitude, optimize the weighting coefficients of the five Rife-Vincent windows and repeat S3 and S4. If it is less than the preset sidelobe level gain amplitude, execute S5. S5. Extract the amplitude of the zero-sequence induced voltage at the target frequency from the zero-sequence voltage drop waveform spectrum table at the beginning and end. Calculate the mutual inductance parameters of the double-circuit transmission line on the same tower based on the amplitude of the target frequency current signal and the amplitude of the zero-sequence induced voltage at the target frequency.

2. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, The spectrum analysis of the zero-sequence voltage drop waveform at the beginning and end of the waveform is performed using a five-term Rife-Vincent window and a four-line interpolation algorithm, resulting in a spectrum table of the zero-sequence voltage drop waveform at the beginning and end of the waveform, as follows: A five-term Rife-Vincent window is added to the zero-sequence voltage drop waveform at both ends; A fast Fourier transform is performed on the zero-sequence voltage drop waveform at the beginning and end after applying a five-term Rife-Vincent window to obtain the initial zero-sequence voltage drop waveform spectrum table. The initial zero-sequence voltage drop waveform spectrum table at the beginning and end is corrected by using a four-line interpolation algorithm to obtain the zero-sequence voltage drop waveform spectrum table at the beginning and end.

3. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, The optimization of the weighting coefficients of the five Rife-Vincent windows is specifically as follows: The weighting coefficients of the five Rife-Vincent windows are optimized using Newton's method or gradient descent method.

4. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, When optimizing the weighting coefficients of the five Rife-Vincent windows, the following conditions must be met: The main lobe level of the zero-sequence voltage drop waveform spectrum table at the beginning and end does not exceed the preset main lobe level gain amplitude, and the weighting coefficients of the five Rife-Vincent windows are forced to be symmetrical.

5. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, The extraction of the zero-sequence induced voltage amplitude at the target different frequency from the zero-sequence voltage drop waveform spectrum table at the beginning and end is specifically as follows: Using the target frequency as an index, traverse the spectrum table of the zero-sequence voltage drop waveform at the beginning and end to obtain the amplitude of the zero-sequence induced voltage at the target frequency.

6. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, The mutual inductance parameters of the double-circuit transmission line on the same tower are calculated based on the amplitude of the target frequency current signal and the amplitude of the zero-sequence induced voltage at the target frequency. Specifically: In the formula, For mutual inductance parameters of a double-circuit transmission line on the same tower; The zero-sequence induced voltage amplitude at the target frequency; The amplitude of the frequency-differential current in the first circuit under the target frequency; The amplitude of the frequency-differential current in the second circuit under the target frequency; For complex units; The angular frequency of the target different frequency; The resistance between the beginning and end of the first circuit; This refers to the inductance between the beginning and end of the first circuit.

7. The method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower according to claim 1, characterized in that, The different frequency current signal is a current signal that deviates from the power frequency by ±10Hz.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower as described in any one of claims 1 to 7.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower as described in any one of claims 1 to 7.

10. A computer program product, characterized in that, When executed by a processor, the computer program product implements a method for measuring mutual inductance parameters of a double-circuit transmission line on the same tower as described in any one of claims 1 to 7.

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