CN116125188A - Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification - Google Patents

Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification Download PDF

Info

Publication number
CN116125188A
CN116125188A CN202211191033.XA CN202211191033A CN116125188A CN 116125188 A CN116125188 A CN 116125188A CN 202211191033 A CN202211191033 A CN 202211191033A CN 116125188 A CN116125188 A CN 116125188A
Authority
CN
China
Prior art keywords
commutation
identification value
identification
harmonic
frequency deviation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202211191033.XA
Other languages
Chinese (zh)
Inventor
靳宗帅
张恒旭
刘远龙
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong University
Original Assignee
Shandong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong University filed Critical Shandong University
Priority to CN202211191033.XA priority Critical patent/CN116125188A/en
Publication of CN116125188A publication Critical patent/CN116125188A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/02—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/16—Spectrum analysis; Fourier analysis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/16—Spectrum analysis; Fourier analysis
    • G01R23/165—Spectrum analysis; Fourier analysis using filters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/088—Aspects of digital computing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Abstract

The invention discloses a commutation failure early warning method and a commutation failure early warning system based on commutation voltage time-varying harmonic identification, and relates to the technical field of broadband measurement of power systems and application. And a theoretical functional relation between the frequency deviation identification value and the frequency deviation true value under the condition that the harmonic frequency deviates from the center frequency of the Taylor Fourier transform filter passband is given, a nonlinear equation between the frequency deviation identification value and the true value is further constructed, and the nonlinear equation is solved through Newton iteration to obtain the frequency deviation true value, so that high-precision identification of time-varying harmonic frequency, amplitude, phase and damping ratio coefficients is realized. And on the basis of the harmonic identification result, calculating and predicting the maximum commutation area change trend of the commutation voltage energy supply by using the commutation voltage harmonic identification data, so as to realize commutation failure early warning. The method has extremely high engineering application value in the aspect of time-varying harmonic high-precision real-time identification and commutation failure early warning of the high-voltage direct-current transmission system.

Description

Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification
Technical Field
The invention relates to the field of broadband measurement technology and application of power systems, in particular to a commutation failure early warning method and system based on the recognition of a time-varying harmonic of a commutation voltage.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
Because the thyristors adopted by the phase-change converter have no self-turn-off capability, the phase-change failure is easy to be caused when the voltage support of the alternating-current system at the inversion side is insufficient, and the direct-current blocking can be caused by the repeated phase-change failure, so that the power grids at the transmission end and the receiving end are subjected to serious active disturbance, the power grids with insufficient physical inertia support can possibly excite the cascading failure, and the safe and stable operation of the alternating-current and direct-current hybrid power grid is threatened. The nonlinear characteristics of the power electronic device are affected by various factors such as an operation environment, a control mode, a fault type and the like, and generated harmonic waves have time-varying characteristics, so how to identify the time-varying harmonic waves with high precision and high speed is an important precondition for commutation failure analysis, early warning and suppression.
At present, the discrete fourier transform (Discrete Fourier Transform, DFT) method is the most commonly used harmonic identification method for the power failure wave recording monitoring device of the converter station due to the advantages of simplicity and easiness in implementation. However, the frequency spectrum leakage problem exists in the DFT under the condition of frequency offset, and particularly, the recognition accuracy is greatly reduced under the condition of wide frequency offset of a weak inertia system. The improved DFT method based on the sampling interval self-adaptive adjustment technology of the phase-locked loop, the self-adaptive soft synchronization technology based on the sampling sequence interpolation and the frequency spectrum leakage suppression technology based on the frequency domain interpolation can improve the identification precision under the condition of frequency offset to a certain extent, but cannot fundamentally solve the frequency spectrum leakage problem. Besides the Fourier transform-based method, there are parameter identification methods, such as Prony method and rotation invariant technology signal parameter estimation (Estimation of Signal Parameters via Rotational Invariance Techniques, ESPRIT) method, which use exponential function linear combination to build a signal model, firstly use techniques such as autocorrelation, covariance, autocorrelation, singular value decomposition and the like to estimate frequency, then solve phasors by solving a linear regression model which builds a relation between the phasors and the signal, so that not only frequency, amplitude and phase can be identified, but also damping ratio coefficient identification values can be identified, and pre-judgment information is provided for analyzing the influence of harmonic variation on phase conversion failure. However, the recognition performance and model order selection of the Prony method and the ESPRIT method are closely related to noise level. It should be noted that, the fourier transform-based method and the parameter class identification method are both window sampling sequence processing methods under the condition of assuming stable signals, the signals need to be divided into a series of continuous short windows, but the signals in each short window are still approximately considered to be stable, and only approximate tracking of time-varying harmonics can be realized through window sliding.
The Taylor Fourier transform (Taylor Fourier Transform, TFT) method directly considers the time-varying characteristics of the signals in a signal identification model by performing Taylor series expansion on harmonic phasors, solves a TFT filter bank by a Least Square (LS) method, approximates the variation trend of each frequency component in a frequency domain by utilizing the band-pass filter characteristic of the TFT filter bank, and further identifies the harmonic frequency and the phasors. To further suppress interference of the stop band component, a window function with a lower side lobe level may be used to weight the sample sequence in the observation window, which may greatly attenuate the stop band side lobe level. However, because the flat range of the TFT filter passband is limited, the center frequency of the filter passband needs to be iteratively adjusted by using the feedback of the frequency identification result, so that the center frequency gradually approaches to the real frequency, and high-precision identification is realized under the conditions of frequency offset and frequency dynamic change. However, each iteration needs to recalculate the TFT filter bank, needs to calculate a plurality of intermediate variable matrices, performs complex computation of complex matrix multiplication and inversion, and heavy computation load and memory overhead are major obstacles for TFT method engineering application.
Therefore, it is necessary to design a high-precision rapid identification method of commutation voltage time-varying harmonic and apply the method to commutation failure early warning.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide a commutation failure early warning method and a commutation failure early warning system based on the time-varying harmonic identification of the commutation voltage, which can realize the high-precision identification of the harmonic under the frequency deviation scene, the frequency slope and the frequency oscillation dynamic scene, and calculate and predict the maximum commutation area variation trend of the commutation voltage energy supply by utilizing the commutation voltage harmonic identification data on the basis of the harmonic identification result so as to realize the commutation failure early warning. The parameters required by the method are obtained through offline calculation, no intermediate variable is required to be stored, the memory requirement is small, the calculation complexity is low, and the method has extremely high engineering application value in the aspects of time-varying harmonic high-precision real-time identification and commutation failure early warning of a high-voltage direct-current transmission system.
In order to achieve the above object, the present invention is realized by the following technical scheme:
the invention provides a commutation failure early warning method based on commutation voltage time-varying harmonic identification, which comprises the following steps:
acquiring a signal sampling sequence to obtain a primary identification value of harmonic parameters; the harmonic parameter preliminary identification value comprises an amplitude identification value, a phase identification value and a frequency deviation identification value;
constructing a functional relation between the frequency deviation identification value and the frequency deviation true value according to the frequency response function of the Taylor Fourier transform filter bank;
updating the frequency deviation identification value through a frequency deviation iterative correction process;
and obtaining a frequency identification value according to the updated frequency deviation identification value, updating an amplitude identification value and a phase identification value according to the frequency identification value, obtaining a damping ratio coefficient identification value, and pre-warning the risk of commutation failure according to a commutation area prediction formula.
Further, a functional relation between the frequency deviation identification value and the frequency deviation true value is constructed in an off-line mode.
Further, a harmonic parameter preliminary identification value is obtained according to a signal sampling sequence and a calculation formula of harmonic phasors and derivatives thereof.
Further, a functional relation between the frequency deviation identification value and the frequency deviation true value is constructed, and specifically, a theoretical functional relation between the frequency deviation identification value and the frequency deviation true value under the condition that the harmonic frequency deviates from the center frequency of the Taylor Fourier transform filter passband is constructed.
Further, the primary identification value of the harmonic parameter is updated according to the updated frequency deviation identification value, and the specific process is that the center frequency of the harmonic filtering passband of the Taylor Fourier transform filter bank is set, the updated frequency identification value is obtained according to the sum of the updated frequency deviation identification value and the center frequency of the harmonic filtering passband of the Taylor Fourier transform filter bank, and then the updated amplitude identification value and the phase identification value are obtained.
Further, the commutation area prediction formula considers the harmonic amplitude, frequency, phase and damping ratio coefficient identification value, and when the value of the closing angle is the minimum Guan Duanjiao required by the converter valve to recover the forward blocking capability, the commutation area supplied by the commutation voltage energy is the maximum commutation area.
Further, when the maximum commutation area is smaller than the required commutation area, it is determined that there is a risk of commutation failure.
The second aspect of the invention provides a commutation failure early warning system based on the time-varying harmonic identification of the commutation voltage, comprising:
the data acquisition module is configured to acquire a signal sampling sequence to obtain a primary identification value of the harmonic parameter; the harmonic parameter preliminary identification value comprises an amplitude identification value, a phase identification value and a frequency deviation identification value;
a first data processing module configured to construct a functional relationship of the frequency deviation identification value and the frequency deviation true value from the taylor fourier transform filter bank frequency response function;
the second data processing module is configured to update the frequency deviation identification value through a frequency deviation iterative correction process;
the commutation failure early warning module is configured to obtain a frequency identification value according to the updated frequency deviation identification value, update an amplitude identification value and a phase identification value according to the frequency identification value, obtain a damping ratio coefficient identification value and early warn commutation failure risk according to a commutation area prediction formula.
A third aspect of the present invention provides a medium having stored thereon a program which, when executed by a processor, implements the steps in a commutation failure early warning method based on a commutation voltage time-varying harmonic identification according to the first aspect of the present invention.
A fourth aspect of the present invention provides an apparatus comprising a memory, a processor and a program stored on the memory and executable on the processor, the processor implementing the steps in the commutation failure early warning method based on the commutation voltage time-varying harmonic identification according to the first aspect of the present invention when the program is executed.
The one or more of the above technical solutions have the following beneficial effects:
according to the commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage, provided by the invention, the theoretical function relation between the frequency deviation identification value and the frequency deviation true value under the condition that the harmonic frequency deviates from the center frequency of the Taylor Fourier transform filter passband is provided, so that a nonlinear equation between the frequency deviation identification value and the true value is constructed, the nonlinear equation is solved through Newton iteration, the frequency deviation true value is obtained, and therefore, the high-precision identification of the time-varying harmonic frequency, amplitude, phase and damping ratio coefficient is realized. The parameters required by the provided phase-change voltage time-varying harmonic quick identification method are obtained through offline calculation, any intermediate variable is not required to be stored, the memory requirement is small, the Taylor Fourier transform filter bank is not required to be recalculated, and the calculation complexity is extremely low.
Based on the harmonic identification result, the invention provides a commutation area prediction formula considering harmonic frequency, amplitude, phase and damping ratio coefficient, and calculates and predicts the maximum commutation area change trend of the commutation voltage energy supply by using the commutation voltage harmonic identification data to early warn commutation failure. Therefore, the method has extremely high engineering application value in the aspect of time-varying harmonic high-precision real-time identification and commutation failure early warning of the high-voltage direct-current transmission system.
Additional aspects of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.
Fig. 1 is a flowchart of a commutation failure early warning method based on a commutation voltage time-varying harmonic identification according to an embodiment of the invention.
The specific embodiment is as follows:
it should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;
embodiment one:
the embodiment of the invention provides a commutation failure early warning method based on commutation voltage time-varying harmonic identification, which comprises the following steps:
acquiring a signal sampling sequence to obtain a primary identification value of harmonic parameters; the harmonic parameter preliminary identification value comprises an amplitude identification value, a phase identification value and a frequency deviation identification value;
constructing a functional relation between the frequency deviation identification value and the frequency deviation true value according to the frequency response function of the Taylor Fourier transform filter bank;
updating the frequency deviation identification value through a frequency deviation iterative correction process;
and obtaining a frequency identification value according to the updated frequency deviation identification value, updating an amplitude identification value and a phase identification value according to the frequency identification value, obtaining a damping ratio coefficient identification value, and pre-warning the risk of commutation failure according to a commutation area prediction formula.
As a further technical solution, in this embodiment, there is no relation between the step of obtaining the preliminary identification value of the harmonic parameter and the step of constructing the functional relation between the frequency deviation identification value and the frequency deviation actual value, as shown in fig. 1, in some embodiments, the functional relation between the frequency deviation identification value and the frequency deviation actual value may be constructed offline, and then the signal sampling sequence may be obtained.
As a further technical scheme, the harmonic parameter preliminary identification value is obtained according to a signal sampling sequence and a calculation formula of harmonic phasors and derivatives thereof.
The method comprises the following specific steps: acquisition signal sampling sequence s= [ S ] 0 ,s 1 ,s 2 ,……,s N-1 ] T The calculation formula of the kth derivative of the mth harmonic phasor is as follows
Figure SMS_1
Preliminarily obtaining an amplitude identification value ++>
Figure SMS_2
Phase identification value->
Figure SMS_3
Frequency deviation recognition value->
Figure SMS_4
Figure SMS_5
Figure SMS_6
Figure SMS_7
Wherein abs []Representing the amplitude value, angle [ []Representing the phase, imag [ []The representation takes the imaginary part.
Figure SMS_8
The kth derivative taylor fourier transform filter bank parameter, which is the mth harmonic phasor, is derived from: initializing Taylor Fourier transform Filter set parameter matrix +.>
Figure SMS_9
It is a matrix of M (K+1) rows and N columns; />
Figure SMS_10
The (m-1) (K+1) +k+1 line parameter is the kth derivative Taylor Fourier transform Filter bank parameter of the mth harmonic phasor, denoted +.>
Figure SMS_11
As a further technical scheme, a functional relation between the frequency deviation identification value and the frequency deviation true value is constructed, and particularly, a theoretical functional relation between the frequency deviation identification value and the frequency deviation true value under the condition that the harmonic frequency deviates from the center frequency of the Taylor Fourier transform filter passband is constructed.
The frequency identification value is obtained according to the updated frequency deviation identification value, the amplitude identification value and the phase identification value are updated according to the frequency identification value, and the specific process is that the center frequency of a harmonic wave filtering passband of the Taylor Fourier transform filter bank is set, the frequency identification value is obtained according to the sum of the updated frequency deviation identification value and the center frequency of the harmonic wave filtering passband of the Taylor Fourier transform filter bank, and then the updated amplitude identification value and the updated phase identification value are obtained according to the frequency identification value.
The method comprises the following specific steps:
setting the harmonic filtering passband center frequency omega of a Taylor Fourier transform filter bank Cm Wherein m=1, 2, … …, M represents the mth harmonic and M represents the maximum harmonic order; setting the signal sampling rate to F s Sampling interval is
Figure SMS_12
The filter window length is N and the Taylor expansion order is K. Off-line computing Taylor Fourier transform filter group parameter matrix +.>
Figure SMS_13
Calculating the Taylor Fourier transform filter bank frequency response function offline: the kth derivative Taylor Fourier transform Filter Bank frequency response function of the mth harmonic phasor is
Figure SMS_14
Wherein E is FR Representing a frequency twiddle factor column vector, E FR ＝[1，e jω ，e j2ω ，…，e j(N-1)ω ] T ，[] T The transpose of the matrix is represented,
Figure SMS_15
indicative of amplitude-frequency response, < >>
Figure SMS_16
Representing the phase-frequency response, ω being frequency.
Frequency deviation identification value
Figure SMS_17
True value Δω from frequency deviation m Is a functional relation of (2)
Figure SMS_18
For a pair of
Figure SMS_19
Fitting a polynomial to obtain ++>
Figure SMS_20
Wherein Q is the fitting order, u q Fitting parameters for the q-th order.
Constructing a frequency deviation nonlinear equation according to the preliminary frequency deviation identification value
Figure SMS_21
And its derivative->
Figure SMS_22
Initialization->
Figure SMS_23
The frequency deviation iterative correction process is shown in the following formula, and the iterative times are J +.>
Figure SMS_24
The result is the jth iteration result;
Figure SMS_25
updating frequency deviation identification value
Figure SMS_26
According to the updated frequency deviation recognition value +.>
Figure SMS_27
Updating the amplitude recognition value according to the frequency recognition value>
Figure SMS_28
And phase identification value->
Figure SMS_29
Figure SMS_30
Figure SMS_31
Figure SMS_32
Figure SMS_33
As a further technical proposal, the damping ratio coefficient identification value is
Figure SMS_34
Wherein ln []As a natural logarithmic function>
Figure SMS_35
T is the identification result of the previous window report To identify window time intervals.
The commutation area prediction formula considers the harmonic amplitude, frequency, phase and damping ratio coefficient identification value, and when the value of the closing angle is the minimum Guan Duanjiao required by the forward blocking capacity recovery of the converter valve, the commutation area of the commutation voltage energy supply is the maximum commutation area. And when the maximum commutation area is smaller than the required commutation area, judging that the commutation failure risk exists.
Specifically, the phase-change area prediction formula considering the harmonic wave and the damping ratio coefficient identification value thereof is as follows
Figure SMS_36
Wherein, the liquid crystal display device comprises a liquid crystal display device,
Figure SMS_37
alpha is the trigger advance angle, and gamma is the off angle. When the gamma is the minimum Guan Duanjiao gamma required by the converter valve to restore the forward blocking capacity min When Y is ca The maximum commutation area available for commutation voltage energy is noted as
Figure SMS_38
T pred The early warning duration is the early warning duration;
if it is
Figure SMS_39
If the current is smaller than the required commutation area, determining that T is pred There is then a risk of commutation failure occurring. The required commutation area can be obtained by manual setting.
Embodiment two:
the second embodiment of the invention provides a commutation failure early warning system based on the time-varying harmonic identification of a commutation voltage, which comprises:
the data acquisition module is configured to acquire a signal sampling sequence to obtain a primary identification value of the harmonic parameter; the harmonic parameter preliminary identification value comprises an amplitude identification value, a phase identification value and a frequency deviation identification value;
a first data processing module configured to construct a functional relationship of the frequency deviation identification value and the frequency deviation true value from the taylor fourier transform filter bank frequency response function;
the second data processing module is configured to update the frequency deviation identification value through a frequency deviation iterative correction process;
the commutation failure early warning module is configured to obtain a frequency identification value according to the updated frequency deviation identification value, update an amplitude identification value and a phase identification value according to the frequency identification value, obtain a damping ratio coefficient identification value and early warn commutation failure risk according to a commutation area prediction formula.
Embodiment III:
the third embodiment of the invention provides a medium, on which a program is stored, which when executed by a processor, implements the steps in the commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage according to the first embodiment of the invention.
Embodiment four:
the fourth embodiment of the invention provides a device, which comprises a memory, a processor and a program stored on the memory and capable of running on the processor, wherein the processor realizes the steps in the commutation failure early warning method based on the phase-change voltage time-varying harmonic identification according to the first embodiment of the invention when executing the program.
The steps involved in the devices of the second, third and fourth embodiments correspond to those of the first embodiment of the method, and the detailed description of the embodiments can be found in the related description section of the first embodiment. The term "computer-readable storage medium" should be taken to include a single medium or multiple media including one or more sets of instructions; it should also be understood to include any medium capable of storing, encoding or carrying a set of instructions for execution by a processor and that cause the processor to perform any one of the methods of the present invention.
It will be appreciated by those skilled in the art that the modules or steps of the invention described above may be implemented by general-purpose computer means, alternatively they may be implemented by program code executable by computing means, whereby they may be stored in storage means for execution by computing means, or they may be made into individual integrated circuit modules separately, or a plurality of modules or steps in them may be made into a single integrated circuit module. The present invention is not limited to any specific combination of hardware and software.
While the foregoing description of the embodiments of the present invention has been presented in conjunction with the drawings, it should be understood that it is not intended to limit the scope of the invention, but rather, it is intended to cover all modifications or variations within the scope of the invention as defined by the claims of the present invention.

Claims (10)

1. The commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage is characterized by comprising the following steps:
acquiring a signal sampling sequence to obtain a primary identification value of harmonic parameters; the harmonic parameter preliminary identification value comprises an amplitude identification value, a phase identification value and a frequency deviation identification value;
constructing a functional relation between the frequency deviation identification value and the frequency deviation true value according to the frequency response function of the Taylor Fourier transform filter bank;
updating the frequency deviation identification value through a frequency deviation iterative correction process;
and obtaining a frequency identification value according to the updated frequency deviation identification value, updating an amplitude identification value and a phase identification value according to the frequency identification value, obtaining a damping ratio coefficient identification value, and pre-warning the risk of commutation failure according to a commutation area prediction formula.
2. The commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage according to claim 1, wherein the functional relation between the frequency deviation identification value and the frequency deviation true value is constructed in an off-line manner.
3. The commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage according to claim 1, wherein the preliminary identification value of the harmonic parameter is obtained according to a signal sampling sequence and a calculation formula of the harmonic phasor and its derivative.
4. The commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage according to claim 1, wherein a functional relation of the frequency deviation identification value and the frequency deviation actual value is constructed, in particular a theoretical functional relation of the frequency deviation identification value and the frequency deviation actual value under the condition that the harmonic frequency deviates from the center frequency of the taylor fourier transform filter passband.
5. The commutation failure early warning method based on time-varying harmonic identification of the commutation voltage according to claim 4, wherein the primary identification value of the harmonic parameter is updated according to the updated frequency deviation identification value, and the specific process is that the center frequency of the harmonic filtering passband of the taylor fourier transform filter bank is set, and the updated frequency identification value is obtained according to the sum of the updated frequency deviation identification value and the center frequency of the harmonic filtering passband of the taylor fourier transform filter bank, so as to obtain the updated amplitude identification value and the phase identification value.
6. The commutation failure early warning method based on the time-varying harmonic identification of the commutation voltage according to claim 1, wherein the commutation area prediction formula considers the harmonic amplitude, the frequency, the phase and the damping ratio coefficient identification value, and when the value of the off angle is the minimum Guan Duanjiao required by the commutation valve to recover the forward blocking capability, the commutation area of the commutation voltage energy supply is the maximum commutation area.
7. The commutation failure early warning method based on the commutation voltage time-varying harmonic identification of claim 6, wherein the risk of commutation failure is determined to occur when the maximum commutation area is smaller than the required commutation area.
8. Commutation failure early warning system based on commutation voltage time-varying harmonic identification, characterized by comprising:
the data acquisition module is configured to acquire a signal sampling sequence to obtain a primary identification value of the harmonic parameter;
a first data processing module configured to construct a functional relationship of the frequency deviation identification value and the frequency deviation true value from the taylor fourier transform filter bank frequency response function;
the second data processing module is configured to update the frequency deviation identification value through a frequency deviation iterative correction process;
the commutation failure early warning module is configured to update the primary identification value of the harmonic parameter according to the updated frequency deviation identification value, obtain the damping ratio coefficient identification value and early warn commutation failure risk according to a commutation area prediction formula.
9. A computer readable storage medium, characterized in that a plurality of instructions are stored, which instructions are adapted to be loaded by a processor of a terminal device and to perform the commutation failure early warning method based on the commutation voltage time-varying harmonic identification of any one of claims 1-7.
10. A terminal device comprising a processor and a computer readable storage medium, the processor configured to implement instructions; a computer readable storage medium for storing a plurality of instructions adapted to be loaded by a processor and to perform the commutation failure early warning method of any one of claims 1-7 based on commutation voltage time-varying harmonic identification.
CN202211191033.XA 2022-09-28 2022-09-28 Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification Pending CN116125188A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211191033.XA CN116125188A (en) 2022-09-28 2022-09-28 Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211191033.XA CN116125188A (en) 2022-09-28 2022-09-28 Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification

Publications (1)

Publication Number Publication Date
CN116125188A true CN116125188A (en) 2023-05-16

Family

ID=86301486

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211191033.XA Pending CN116125188A (en) 2022-09-28 2022-09-28 Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification

Country Status (1)

Country Link
CN (1) CN116125188A (en)

Similar Documents

Publication Publication Date Title
CN110061615B (en) Stator current harmonic compensation method for nonlinear characteristic of inverter
Johansson Identification of continuous-time models
CN108037361B (en) High-precision harmonic parameter estimation method based on sliding window DFT
CN108896820B (en) Phase modulator startup protection phasor calculation method suitable for starting static frequency converter
CN105137185A (en) Frequency domain interpolation electric power harmonic wave analysis method based on discrete Fourier transform
CN109521275B (en) Synchronous phasor determination method, system, device and readable storage medium
CN111222088B (en) Improved method for estimating weighted power harmonic amplitude of flat-top self-convolution window
CN104993480A (en) Power system low-frequency oscillation online identification method based on recursive stochastic subspace
CN103323651B (en) Based on the variable step affine projection harmonic current detecting method that time coherence is average
CN109684937B (en) Signal denoising method and device based on FFT and mathematical morphology method
CN116125188A (en) Commutation failure early warning method and system based on commutation voltage time-varying harmonic identification
de la O Serna et al. Smart grids Part 2: Synchrophasor measurement challenges
Allenmber et al. A simple Fourier analysis technique for measuring the dynamic response of manual control systems
CN105550516A (en) Adams algorithm based frequency adaptive harmonic and inter-harmonic analysis method
CN111948454A (en) Synchronous phasor measurement method and system for resisting attenuated direct current component interference
CN111711204A (en) Positive and negative sequence component detection method, control device and storage medium
Fedele et al. Multi-sinusoidal signal estimation by an adaptive SOGI-filters bank
Terzija Improved recursive Newton-type algorithm for power system relaying and measurement
CN116400144A (en) Dynamic detection method, device and detection circuit for direct current bus capacitance state
Serov et al. Method to reduce the measurement error of the spectrum by the demodulation technique
US20140174946A1 (en) System and method for estimating impedance in electrochemical impedance spectroscopy
CN113672863A (en) Simplified phasor calculation method and system for generator startup protection
CN112557751A (en) Harmonic parameter estimation method based on DFT iteration method
CN117074778B (en) Harmonic extraction method and device based on load scene and computer equipment
CN115276120B (en) Model-free predictive control method and system for power converter

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination