Novel method and device for measuring broadband phasor of power system

Abstract

The invention relates to the technical field of electric power system operation monitoring, in particular to a novel electric power system broadband phasor measurement method and device, and the method comprises the steps: obtaining the requirements of a user for the quantitative indexes of the calculation precision and the response speed of the broadband phasor, and obtaining the measurement result of the broadband phasor based on a plurality of frequency points which are used for testing and are set in a target frequency band; forming a frequency test set, establishing at least one constraint condition which needs to be met by the frequency of the broadband phasor and the time window length adopted for measurement according to requirements, and analyzing the feasible window length which meets the constraint condition and corresponds to each frequency test point in the frequency test set according to the constraint condition; and determining a division scheme of the target frequency range and the time window length adopted by each segment according to the feasible window length, and obtaining a measurement result of the broadband phasor according to the division scheme and the time window length adopted by each segment. Therefore, the problem that the phasor measurement precision and the response speed are difficult to take into account on the basis of easy engineering implementation in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the technical field of power system operation monitoring, and in particular to a novel method and device for measuring wide-band phasors of a power system. Background Art

[0002] In the related technology, the wideband phasor measurement method can be mainly divided into two categories: time domain method and frequency domain method. The time domain method needs to establish an accurate signal model according to the number of modes, and the frequency domain method is based on DFT (Discrete Fourier Transform) and FFT (Fast Fourier Transform). The calculation is simple and easy to implement, and the influence of DFT spectrum leakage and fence effect on measurement accuracy is reduced by windowing and interpolation methods.

[0003] However, in the related technology, on the one hand, due to the unknown and time-varying nature of the oscillation modes of the actual system, the parameters calculated by using the time domain method to establish a fixed model are inaccurate, and the solution process is complicated and the amount of calculation is too large, which is not conducive to engineering applications; on the other hand, interpolation DFT is mainly used for the measurement of sub / super-synchronous phasors, and it is difficult to take into account the accuracy and response speed of phasor measurement over a wide frequency band of several Hz to several thousand Hz.

[0004] In summary, in the related technologies, it is difficult to balance the accuracy and response speed of phasor measurement on the basis of easy engineering implementation, which urgently needs to be improved. Summary of the invention

[0005] The present application provides a novel method and device for measuring wide-band phasors in a power system to solve the problem in related technologies that it is difficult to balance the accuracy and response speed of phasor measurement on the basis of easy engineering implementation.

[0006] The first aspect of the present application provides a novel method for measuring wideband phasors in a power system, comprising the following steps: obtaining user requirements for quantitative indicators of calculation accuracy and response speed of wideband phasors; forming a frequency test set based on multiple frequency points set in a target frequency band for testing; establishing at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the time window length used for measurement according to the requirements of the quantitative indicators; analyzing the feasible window lengths that meet the constraints corresponding to each frequency test point in the frequency test set according to the at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the time window length established; determining a division scheme for the target frequency range and the time window length used for each segment according to the feasible window length, so as to obtain the measurement result of the wideband phasor according to the division scheme and the time window length used for each segment.

[0007] Through the above technical scheme, the embodiment of the present application can accurately meet the actual application needs by obtaining the user's quantitative index requirements for broadband phasor calculation accuracy and response speed, thereby ensuring the effectiveness and practicality of the measurement results. Secondly, setting a frequency test set in the target frequency band provides a basis for comprehensively evaluating the situation at different frequencies and ensures the comprehensiveness of the measurement. Furthermore, the constraints of frequency and time window length are established based on quantitative indicators, and the feasible window length is analyzed accordingly, thereby realizing the scientific planning and optimization of key parameters of the measurement process. Finally, the target frequency range division scheme and the length of each segmented time window are determined according to the feasible window length, which can effectively adapt to the broadband measurement requirements while taking into account accuracy and response speed, thereby improving the accuracy and reliability of broadband phasor measurement, and providing strong support for the online analysis and suppression of broadband oscillation problems in new power systems, and ensuring the safe and stable operation of power systems.

[0008] Optionally, in one embodiment of the present application, obtaining the user's requirements for quantitative indicators of wide-band phasor calculation accuracy and response speed includes: obtaining the requirements for quantitative indicators of wide-band phasor calculation accuracy based on the measurement errors of the amplitude, frequency and phase of the wide-band phasor; and obtaining the requirements for quantitative indicators of response speed based on the response time of the phasor frequency calculation.

[0009] Through the above technical solution, the embodiment of the present application can determine the quantitative index requirements of calculation accuracy based on the measurement errors of the amplitude, frequency and phase of the wide-band phasor, comprehensively and accurately measure the accuracy of the measurement results, and ensure that the measurement of the wide-band phasor can achieve the expected accuracy in each key parameter. In terms of response speed, the quantitative index requirements for response speed are obtained according to the response time of the phasor frequency calculation, so that the measurement method can closely fit the demand for rapid acquisition of measurement results in the actual power system operation monitoring, and timely reflect the dynamic changes of the system. The quantitative index requirements of calculation accuracy and response speed are obtained based on key measurement parameters respectively, which provides a clear and reasonable basis for the formulation and implementation of subsequent measurement plans, and helps to achieve effective control and optimization of accuracy and speed in the entire measurement process, thereby improving the practicality and reliability of wide-band phasor measurement in new power systems.

[0010] Optionally, in one embodiment of the present application, the requirement for the quantitative index of broadband phasor calculation accuracy is:

[0011]

[0012] Among them, f k is the theoretical value of the phasor frequency, a k is the theoretical value of the phasor amplitude, is the absolute error of the phase frequency measurement, is the absolute error of the phase amplitude measurement, is the absolute error of the phase measurement, A f is the upper limit error requirement of the phasor frequency, A a is the upper limit requirement of the error of the phasor amplitude, A φ is the upper limit requirement of the phasor phase error.

[0013] Through the above technical scheme, the embodiment of the present application can provide a clear and accurate accuracy measurement standard for wide-band phasor measurement, so that in the actual measurement process, whether it is the phasor measurement of various frequency components in the power system or the acquisition of amplitude and phase information, strict error control can be performed based on these quantitative indicators, thereby ensuring the safe and stable operation of the power system.

[0014] Optionally, in an embodiment of the present application, the requirement for the quantitative index of response speed is:

[0015]

[0016] Where, ΔT k Calculate the response time for the frequency of the phasor, A r The upper limit requirement of the frequency calculation response time relative to the oscillation period, f k is the theoretical value of the phasor frequency.

[0017] Through the above-mentioned technical scheme, the embodiment of the present application can meet the differences in response speed requirements for broadband oscillations of different frequencies, and can dynamically adjust the response time limit according to the actual frequency, ensuring that the system's demand for rapid response can be met when measuring broadband phasors of different frequencies. It helps to monitor the dynamic characteristics of the power system in real time and accurately within a wide bandwidth, and provide timely and effective data support for timely measures such as suppressing broadband oscillations.

[0018] Optionally, in one embodiment of the present application, the at least one constraint condition is:

[0019]

[0020] Where p(·) is the constraint condition corresponding to the broadband phasor measurement accuracy, q(·) is the constraint condition corresponding to the frequency calculation response time, and N w The length of the time window used for the measurement.

[0021] Through the above technical solutions, the embodiments of the present application can establish targeted restriction rules from different angles, such as measurement accuracy and frequency calculation response time. By comprehensively considering the constraints of these two aspects, it is possible to ensure that the measurement results meet the requirements in terms of accuracy during the wide-band phasor measurement process, while achieving a fast frequency calculation response, effectively balancing the relationship between measurement accuracy and response speed. This helps to take reasonable suppression measures to ensure the safe and stable operation of the power system and improve the overall performance of the system.

[0022] The second aspect of the present application provides a novel device for measuring wideband phasors in a power system, comprising: an acquisition module for acquiring user requirements for quantitative indicators of calculation accuracy and response speed of wideband phasors; an integration module for forming a frequency test set based on multiple frequency points for testing set in a target frequency band; a construction module for establishing at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the time window length used for measurement according to the requirements of the quantitative indicators; an analysis module for analyzing the feasible window lengths that meet the constraints corresponding to each frequency test point in the frequency test set according to the at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the time window length; and a measurement module for determining a division scheme of the target frequency range and the time window length used for each segment according to the feasible window length, so as to obtain the measurement result of the wideband phasor according to the division scheme and the time window length used for each segment.

[0023] Through the above technical scheme, the embodiment of the present application can accurately meet the actual application needs by obtaining the user's quantitative index requirements for broadband phasor calculation accuracy and response speed, thereby ensuring the effectiveness and practicality of the measurement results. Secondly, setting a frequency test set in the target frequency band provides a basis for comprehensively evaluating the situation at different frequencies and ensures the comprehensiveness of the measurement. Furthermore, the constraints of frequency and time window length are established based on quantitative indicators, and the feasible window length is analyzed accordingly, thereby realizing the scientific planning and optimization of key parameters of the measurement process. Finally, the target frequency range division scheme and the length of each segmented time window are determined according to the feasible window length, which can effectively adapt to the broadband measurement requirements while taking into account accuracy and response speed, thereby improving the accuracy and reliability of broadband phasor measurement, and providing strong support for the online analysis and suppression of broadband oscillation problems in new power systems, and ensuring the safe and stable operation of power systems.

[0024] Optionally, in one embodiment of the present application, the acquisition module includes: a first acquisition unit, used to obtain the quantitative index requirement for the wide-band phasor calculation accuracy based on the measurement errors of the amplitude, frequency and phase of the wide-band phasor; a second acquisition unit, used to obtain the quantitative index requirement for the response speed based on the response time of the phasor frequency calculation.

[0025] Through the above technical solution, the embodiment of the present application can determine the quantitative index requirements of calculation accuracy based on the measurement errors of the amplitude, frequency and phase of the wide-band phasor, comprehensively and accurately measure the accuracy of the measurement results, and ensure that the measurement of the wide-band phasor can achieve the expected accuracy in each key parameter. In terms of response speed, the quantitative index requirements for response speed are obtained according to the response time of the phasor frequency calculation, so that the measurement method can closely fit the demand for rapid acquisition of measurement results in the actual power system operation monitoring, and timely reflect the dynamic changes of the system. The quantitative index requirements of calculation accuracy and response speed are obtained based on key measurement parameters respectively, which provides a clear and reasonable basis for the formulation and implementation of subsequent measurement plans, and helps to achieve effective control and optimization of accuracy and speed in the entire measurement process, thereby improving the practicality and reliability of wide-band phasor measurement in new power systems.

[0026] Optionally, in one embodiment of the present application, the requirement for the quantitative index of broadband phasor calculation accuracy is:

[0027]

[0028] Among them, f k is the theoretical value of the phasor frequency, a k is the theoretical value of the phasor amplitude, is the absolute error of the phase frequency measurement, is the absolute error of the phase amplitude measurement, is the absolute error of the phase measurement, A f is the upper limit error requirement of the phasor frequency, A a is the upper limit requirement of the error of the phasor amplitude, A φ is the upper limit requirement of the phasor phase error.

[0029] Through the above technical scheme, the embodiment of the present application can provide a clear and accurate accuracy measurement standard for wide-band phasor measurement, so that in the actual measurement process, whether it is the phasor measurement of various frequency components in the power system or the acquisition of amplitude and phase information, strict error control can be performed based on these quantitative indicators, thereby ensuring the safe and stable operation of the power system.

[0030] Optionally, in an embodiment of the present application, the requirement for the quantitative index of response speed is:

[0031]

[0032] Where, ΔT k Calculate the response time for the frequency of the phasor, A r The upper limit requirement of the frequency calculation response time relative to the oscillation period, f kis the theoretical value of the phasor frequency.

[0033] Through the above-mentioned technical scheme, the embodiment of the present application can meet the differences in response speed requirements for broadband oscillations of different frequencies, and can dynamically adjust the response time limit according to the actual frequency, ensuring that the system's demand for rapid response can be met when measuring broadband phasors of different frequencies. It helps to monitor the dynamic characteristics of the power system in real time and accurately within a wide bandwidth, and provide timely and effective data support for timely measures such as suppressing broadband oscillations.

[0034] Optionally, in one embodiment of the present application, the at least one constraint condition is:

[0035]

[0036] Where p(·) is the constraint condition corresponding to the broadband phasor measurement accuracy, q(·) is the constraint condition corresponding to the frequency calculation response time, and N w The length of the time window used for the measurement.

[0037] Through the above technical solutions, the embodiments of the present application can establish targeted restriction rules from different angles, such as measurement accuracy and frequency calculation response time. By comprehensively considering the constraints of these two aspects, it is possible to ensure that the measurement results meet the requirements in terms of accuracy during the wide-band phasor measurement process, while achieving a fast frequency calculation response, effectively balancing the relationship between measurement accuracy and response speed. This helps to take reasonable suppression measures to ensure the safe and stable operation of the power system and improve the overall performance of the system.

[0038] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a novel method for measuring wide-band phasors of a power system as described in the above embodiment.

[0039] The fourth aspect of the present application provides a computer-readable storage medium, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned novel method for measuring wide-band phasors of a power system.

[0040] The fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned novel method for measuring wide-band phasors of a power system.

[0041] The embodiment of the present application can determine the calculation accuracy index based on the amplitude, frequency and phase measurement errors, and determine the response speed index based on the phasor frequency calculation response time, so as to provide an accurate measurement standard for measurement, ensure that the measurement reaches the expected accuracy level in each key parameter, and can closely meet the actual needs and reflect the dynamic changes of the system in a timely manner. A frequency test set is set in the target frequency band to ensure a comprehensive evaluation, and frequency and time window length constraints are established based on quantitative indicators and the feasible window length is analyzed to achieve scientific planning and optimization of key parameters, and then determine the target frequency range division scheme and the segmented time window length, so as to adapt to the wideband measurement requirements while taking into account accuracy and response speed, and can not only dynamically adjust the response time according to different frequencies, but also establish restriction rules from different angles to balance the relationship between the two, and ultimately improve the measurement accuracy and reliability, and provide strong support for the online analysis and suppression of broadband oscillation problems in new power systems, and effectively ensure the safe and stable operation of power systems and overall performance improvement.

[0042] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0044] Figure 1 A flow chart of a novel method for measuring wide-band phasors of a power system provided according to an embodiment of the present application;

[0045] Figure 2 A schematic diagram of the structure of a novel device for measuring wide-band phasors of a power system provided according to an embodiment of the present application;

[0046] Figure 3 The figure is a structural example diagram of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0047] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0048] The following describes the measurement method and device of the broadband phasor of the novel power system of the embodiment of the present application with reference to the accompanying drawings. In view of the problem that it is difficult to take into account the accuracy and response speed of phasor measurement on the basis of easy engineering implementation in the related technologies mentioned in the above background technology center, the present application provides a measurement method of broadband phasor of a novel power system, in which the user's quantitative index requirements for broadband phasor calculation accuracy and response speed can be obtained to accurately meet the actual application needs and ensure the effectiveness and practicality of the measurement results. Secondly, setting a frequency test set in the target frequency band provides a basis for comprehensively evaluating the situation at different frequencies and ensures the comprehensiveness of the measurement. Furthermore, the constraints of frequency and time window length are established according to the quantitative indicators, and the feasible window length is analyzed accordingly, so as to realize the scientific planning and optimization of the key parameters of the measurement process. Finally, the target frequency range division scheme and the length of each segmented time window are determined according to the feasible window length, which can effectively adapt to the broadband measurement requirements while taking into account the accuracy and response speed, thereby improving the accuracy and reliability of broadband phasor measurement, providing strong support for the online analysis and suppression of broadband oscillation problems in the novel power system, and ensuring the safe and stable operation of the power system. Thereby, the problem in the related art that it is difficult to take into account both the accuracy and response speed of phasor measurement on the basis of easy engineering implementation is solved.

[0049] Specifically, Figure 1 A flow chart of a novel method for measuring wide-band phasors in a power system provided in an embodiment of the present application.

[0050] like Figure 1 As shown, the novel method for measuring wide-band phasors of power systems includes the following steps:

[0051] In step S101, the user's requirements for the calculation accuracy and response speed of the broadband phasor are obtained.

[0052] It can be understood that quantitative indicators are to transform abstract concepts or requirements into specific, measurable and comparable values ​​or value ranges. In obtaining the user's quantitative indicator requirements for broadband phasor calculation accuracy and response speed, the user's expectations for measurement accuracy and speed are expressed in specific numerical form.

[0053] Optionally, in one embodiment of the present application, the user's requirements for quantitative indicators of wide-band phasor calculation accuracy and response speed are obtained, including: obtaining the requirements for quantitative indicators of wide-band phasor calculation accuracy based on the measurement errors of the amplitude, frequency and phase of the wide-band phasor; and obtaining the requirements for quantitative indicators of response speed based on the response time of the phasor frequency calculation.

[0054] On the one hand, for frequency f k The measurement accuracy requirement of the phase is:

[0055]

[0056] Among them, f k is the theoretical value of the phasor frequency, a k is the theoretical value of the phasor amplitude, is the absolute error of the phase frequency measurement, is the absolute error of the phase amplitude measurement, is the absolute error of the phase measurement, A f is the upper limit error requirement of the phasor frequency, A a is the upper limit requirement of the error of the phasor amplitude, A φ is the upper limit requirement of the phasor phase error.

[0057] On the other hand, for frequency f k The measurement response speed requirement of the phase is:

[0058]

[0059] Where, ΔT k Calculate the response time for the frequency of the phasor, A r The upper limit requirement for the frequency calculation response time relative to the oscillation period.

[0060] The embodiments of the present application can clarify the measurement target through quantitative indicators, set upper limits for calculation accuracy based on amplitude, frequency and phase errors, accurately control measurement accuracy, and provide reliable data for system analysis; the response speed dynamically adjusts the upper limit according to the frequency, responds to oscillations of different frequencies in a timely manner, improves practicality and reliability, and effectively guarantees the operation of the power system.

[0061] In step S102, a frequency test set is formed based on a plurality of frequency points for testing set in the target frequency band.

[0062] It is understandable that the target frequency band refers to the specific frequency range where broadband phasor measurement is required. Since there are multiple frequency components in the power system, especially with the massive access of new energy and power electronic equipment, broadband oscillations from several Hz to several kHz have appeared, so it is necessary to clearly define a frequency range of interest for measurement and analysis. The frequency point is determined based on the characteristics of the frequency band of the measurement target and subsequent algorithm processing.

[0063] In the actual execution process, the frequency test set F includes the start frequency and end frequency of the target frequency band. For example, if the user requires to measure the phasor in the range of 5-2500 Hz, then 5-2500 Hz is the target frequency band, and the frequency test set F can be set to {5, 100, 200, 300, ..., 2400, 2500}.

[0064] The embodiments of the present application can accurately focus on the specific frequency range that needs to be measured and analyzed in the power system by clearly defining the target frequency band, adapt to the broadband oscillation after the power electronic equipment is connected, and comprehensively determine the frequency points based on various factors to form a frequency test set including the start and end frequencies. For example, a corresponding test set is set in the 5-2500Hz target frequency band, and the target frequency band can be effectively discretized. It can not only comprehensively cover the key frequencies in the frequency band, but also provide a complete and orderly data basis for subsequent operations such as establishing constraints based on different frequency points, analyzing feasible window lengths, and reasonably dividing frequency ranges. It helps to realize the scientific planning and precise implementation of broadband phasor measurement, thereby efficiently obtaining broadband phasor measurement results, and providing strong support for accurately grasping the operating characteristics of the power system and ensuring its safe and stable operation.

[0065] In step S103, at least one constraint condition that needs to be satisfied by the frequency of the broadband phasor and the length of the time window used for measurement is established according to the requirement of the quantization index.

[0066] Specifically, at least one constraint is:

[0067]

[0068] Where p(·) is the constraint condition corresponding to the broadband phasor measurement accuracy, q(·) is the constraint condition corresponding to the frequency calculation response time, and N w The length of the time window used for the measurement.

[0069] In some embodiments, when the broadband phasor measurement algorithm adopts three-point interpolation DFT, the constraint condition (sufficient condition) for the phasor measurement accuracy requirement may be:

[0070]

[0071] in, is the normalized result of the spectrum value of the window function used in the interpolation DFT, M is the spectrum number corresponding to the detection frequency f, M0 is the spectrum number corresponding to the power frequency f0, A T is the amplitude threshold for detecting the oscillation mode, that is, if the amplitude of a spectral line in the spectrum exceeds the amplitude of the fundamental wave, T It is considered that the spectrum line corresponds to an oscillation mode.

[0072] The constraints (sufficient conditions) for the response time requirements of phase calculation can be:

[0073]

[0074] Among them, N s and r are intermediate variables, N w is the time window length, N d is the sliding step of the time window, fs is the sampling rate, a(r) is a function, and the expression is as follows:

[0075]

[0076] The embodiment of the present application integrates the quantitative index requirements into it by establishing the constraints of broadband phasor frequency and time window length, thereby realizing the effective control of key elements of the measurement process. When using three-point interpolation DFT, the constraints set for measurement accuracy and frequency calculation response time are sufficient and specific. In terms of accuracy, the constraints constructed based on parameters such as the normalization results of the window function spectrum value can accurately limit the measurement error, ensure that the phasor measurement accuracy meets the standards under different spectrum conditions, and effectively identify the oscillation mode. In terms of response time, through the constraints of multiple related variables, the time window length, sliding step size and sampling rate can be reasonably planned to ensure that the frequency calculation response is fast and timely, and adapt to the measurement requirements of different frequencies. This constraint setting provides a scientific basis for broadband phasor measurement, which helps to balance measurement accuracy and response speed in a complex power system environment, improve the accuracy and reliability of measurement, and thus better serve the analysis and solution of broadband oscillation problems in power systems and ensure stable system operation.

[0077] In step S104, the feasible window lengths satisfying the constraint conditions corresponding to the frequency test points in the frequency test set are analyzed according to at least one constraint condition that the frequency and time window length of the established wideband phasor need to satisfy.

[0078] It can be understood that the feasible window length is the feasible value range or specific value of the time window length determined for each frequency test point in the frequency test set under the constraints of the pre-established wideband phasor frequency and time window length. Since different frequency test points may correspond to different appropriate time window lengths under the constraints, the analysis of the feasible window length is to find out the time window length that can be used for each frequency point while meeting the accuracy and response speed requirements.

[0079] In the actual execution process, each frequency test point in the frequency test set is analyzed one by one. For example, for a set frequency test set F = {5, 100, 200, 300, ..., 2400, 2500}, starting from the lowest frequency of 5Hz, it is substituted into the constraints one by one. Taking the 5Hz frequency test point as an example, its frequency value is substituted into the frequency-related constraint part, and the time window length is considered as a variable. According to the requirements for measurement accuracy and response time in the constraints, mathematical calculations and reasoning are used to determine which values ​​or value ranges the time window length can take while meeting these requirements.

[0080] Furthermore, in the process of calculating and analyzing each frequency test point, the time window length is continuously adjusted to determine whether it satisfies all constraints. If a certain time window length makes the frequency test point meet the pre-set requirements in terms of measurement accuracy and response time, then this time window length is determined as the feasible window length corresponding to the frequency test point. For example, after a series of calculations and judgments, it is found that for the frequency test point of 5Hz, when the time window length is N w1 When all constraints are satisfied, then N w1 It is recorded as a feasible window length for the 5 Hz frequency test point.

[0081] The embodiments of the present application can analyze the feasible window length corresponding to each frequency test point in the frequency test set according to the constraints of the wide-band phasor frequency and the time window length, thereby realizing refined adaptation of the measurement parameters. The embodiments of the present application can fully consider the uniqueness of different frequency test points under the requirements of accuracy and response speed, ensure that each frequency point has the most suitable time window length, avoid measurement errors or inefficiency caused by a unified window length, help improve the accuracy and adaptability of wide-band phasor measurement in the entire target frequency band, accurately capture the characteristics of different frequency components, provide reliable data support for accurate analysis of wide-band oscillations in the power system and stable operation of the system, enhance the practicality and effectiveness of the measurement scheme in a complex power environment, and effectively guarantee the efficient and stable operation of the power system.

[0082] In step S105, a division scheme of the target frequency range and a time window length used for each segment are determined according to the feasible window length, so as to obtain a measurement result of the broadband phasor according to the division scheme and the time window length used for each segment.

[0083] Specifically, the division scheme should be formulated based on the feasible window length of each frequency test point to reasonably and effectively divide the given target frequency range. Since the feasible window lengths corresponding to different frequencies are often different, in order to ensure that the measurements in the entire target frequency range can meet the dual requirements of measurement accuracy and response speed to the greatest extent, while making full use of the advantages corresponding to different feasible window lengths, it is necessary to carefully plan the division scheme.

[0084] In the actual execution process, the starting frequency of the target frequency range is f1, so the time window length of the first segment can be the shortest feasible time window length N corresponding to the frequency f1. w1 , and the termination frequency of the segment can be adopted as an acceptable N w1 The maximum frequency of the window length is f2, and the starting frequency of the second segment is f2, and so on can achieve the division of the entire target frequency range.

[0085] Furthermore, according to the obtained frequency range division scheme and each window length, the wide-band phasor measurement algorithm selected previously is used to measure the wide-band phasor.

[0086] The embodiment of the present application can obtain broadband phasor measurement results by determining the target frequency range division scheme and the length of each segmented time window according to the feasible window length, making full use of the adaptability of the feasible window length to different frequencies, making the selection of the time window length of each segment more scientific, effectively balancing the measurement accuracy and response speed, and reducing the error and delay problems caused by the unified window length. At the same time, it can improve the coverage accuracy of the target frequency range, accurately capture the broadband phasor characteristics at different frequencies, provide more reliable data for the broadband oscillation analysis of the power system, and enhance the practicality and effectiveness of the entire measurement scheme in a complex power environment.

[0087] According to the measurement method of the broadband phasor of the new power system proposed in the embodiment of the present application, the user's quantitative index requirements for broadband phasor calculation accuracy and response speed can be obtained to accurately meet the actual application needs and ensure the effectiveness and practicality of the measurement results. Secondly, a frequency test set is set in the target frequency band to provide a basis for a comprehensive evaluation of the situation at different frequencies and ensure the comprehensiveness of the measurement. Furthermore, the constraints of the frequency and time window length are established based on the quantitative indicators, and the feasible window length is analyzed accordingly, so as to realize the scientific planning and optimization of the key parameters of the measurement process. Finally, the target frequency range division scheme and the length of each segmented time window are determined according to the feasible window length, which can effectively adapt to the broadband measurement requirements while taking into account the accuracy and response speed, thereby improving the accuracy and reliability of broadband phasor measurement, and providing strong support for the online analysis and suppression of broadband oscillation problems in new power systems, and ensuring the safe and stable operation of power systems.

[0088] Next, a novel wide-band phasor measuring device for a power system proposed according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0089] Figure 2 It is a block diagram of a novel device for measuring wide-band phasors of a power system according to an embodiment of the present application.

[0090] like Figure 2 As shown, the novel power system wide-band phasor measuring device 10 comprises: an acquisition module 100 , an integration module 200 , a construction module 300 , an analysis module 400 and a measurement module 500 .

[0091] Specifically, the acquisition module 100 is used to obtain the user's requirements for the quantitative indicators of the calculation accuracy and response speed of the wide-band phasor.

[0092] The integrated module 200 is used to form a frequency test set based on a plurality of frequency points for testing set in a target frequency band.

[0093] The construction module 300 is used to establish at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the length of the time window used for measurement according to the requirement of the quantitative index.

[0094] The analysis module 400 is used to analyze the feasible window lengths satisfying the constraint conditions corresponding to each frequency test point in the frequency test set according to at least one constraint condition that the frequency and time window length of the established wideband phasor need to satisfy.

[0095] The measurement module 500 is used to determine the division scheme of the target frequency range and the time window length used for each segment according to the feasible window length, so as to obtain the measurement result of the broadband phasor according to the division scheme and the time window length used for each segment.

[0096] Optionally, in one embodiment of the present application, the acquisition module 100 includes: a first acquisition unit and a second acquisition unit.

[0097] The first acquisition unit is used to obtain the quantitative index requirement for the calculation accuracy of the wide-band phasor according to the measurement errors of the amplitude, frequency and phase of the wide-band phasor.

[0098] The second acquisition unit is used to obtain the quantitative index requirement for the response speed according to the response time calculated by the phasor frequency.

[0099] Optionally, in one embodiment of the present application, the requirement for the quantitative index of broadband phasor calculation accuracy is:

[0100]

[0101] Among them, f k is the theoretical value of the phasor frequency, a k is the theoretical value of the phasor amplitude, is the absolute error of the phase frequency measurement, is the absolute error of the phase amplitude measurement, is the absolute error of the phase measurement, A f is the upper limit error requirement of the phasor frequency, A a is the upper limit requirement of the error of the phasor amplitude, A φ is the upper limit requirement of the phasor phase error.

[0102] Optionally, in one embodiment of the present application, the requirement for the quantitative index of the response speed is:

[0103]

[0104] Where, ΔT k Calculate the response time for the frequency of the phasor, A r The upper limit requirement of the frequency calculation response time relative to the oscillation period, f kis the theoretical value of the phasor frequency.

[0105] Optionally, in one embodiment of the present application, at least one constraint condition is:

[0106]

[0107] Where p(·) is the constraint condition corresponding to the broadband phasor measurement accuracy, q(·) is the constraint condition corresponding to the frequency calculation response time, and N w The length of the time window used for the measurement.

[0108] It should be noted that the above explanation of the embodiment of the measurement method of the wide-band phasor of the novel power system is also applicable to the measurement device of the wide-band phasor of the novel power system in this embodiment, and will not be repeated here.

[0109] According to the measurement device of the broadband phasor of the new power system proposed in the embodiment of the present application, the user's quantitative index requirements for broadband phasor calculation accuracy and response speed can be obtained to accurately meet the actual application needs and ensure the effectiveness and practicality of the measurement results. Secondly, a frequency test set is set in the target frequency band to provide a basis for a comprehensive evaluation of the situation at different frequencies and ensure the comprehensiveness of the measurement. Furthermore, the constraints of the frequency and time window length are established based on the quantitative indicators, and the feasible window length is analyzed accordingly, so as to realize the scientific planning and optimization of the key parameters of the measurement process. Finally, the target frequency range division scheme and the length of each segmented time window are determined according to the feasible window length, which can effectively adapt to the broadband measurement requirements while taking into account the accuracy and response speed, thereby improving the accuracy and reliability of broadband phasor measurement, and providing strong support for the online analysis and suppression of broadband oscillation problems in new power systems, and ensuring the safe and stable operation of power systems.

[0110] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0111] A memory 301 , a processor 302 , and a computer program stored in the memory 301 and executable on the processor 302 .

[0112] When the processor 302 executes the program, the novel method for measuring wide-band phasors of a power system provided in the above embodiment is implemented.

[0113] Furthermore, the electronic device further comprises:

[0114] The communication interface 303 is used for communication between the memory 301 and the processor 302 .

[0115] The memory 301 is used to store computer programs that can be run on the processor 302 .

[0116] The memory 301 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0117] If the memory 301, the processor 302 and the communication interface 303 are implemented independently, the communication interface 303, the memory 301 and the processor 302 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 3 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0118] Optionally, in a specific implementation, if the memory 301, the processor 302 and the communication interface 303 are integrated on a chip, the memory 301, the processor 302 and the communication interface 303 can communicate with each other through an internal interface.

[0119] The processor 302 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0120] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the novel method for measuring wide-band phasors of a power system as described above.

[0121] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned novel method for measuring wide-band phasors of a power system.

[0122] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0123] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0124] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0125] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0126] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0127] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0128] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0129] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A novel method for measuring broadband phasors in a power system, characterized in that: The following steps are involved: Obtain the user's requirements for the calculation accuracy and response speed of broadband phasors; A frequency test set is formed based on a plurality of frequency points for testing set in a target frequency band; Establishing at least one constraint condition that needs to be satisfied between the frequency of the broadband phasor and the length of the time window used for measurement according to the requirement of the quantitative index; Analyzing the feasible window lengths satisfying the constraint conditions corresponding to each frequency test point in the frequency test set according to at least one constraint condition that the frequency of the established wideband phasor and the time window length need to satisfy; A division scheme of the target frequency range and a time window length used in each segment are determined according to the feasible window length, so as to obtain the measurement result of the broadband phasor according to the division scheme and the time window length used in each segment.

2. The method according to claim 1, characterized in that The obtaining of user requirements for quantitative indicators of broadband phasor calculation accuracy and response speed includes: According to the measurement errors of the amplitude, frequency and phase of the broadband phasor, the quantitative index requirements for the calculation accuracy of the broadband phasor are obtained; The response time calculated based on the phase frequency obtains the quantitative index requirement for the response speed.

3. The method according to claim 2, characterized in that The quantitative index requirements for broadband phasor calculation accuracy are: Among them, f k is the theoretical value of the phasor frequency, a k is the theoretical value of the phasor amplitude, is the absolute error of the phase frequency measurement, is the absolute error of the phase amplitude measurement, is the absolute error of the phase measurement, A f is the upper limit error requirement of the phasor frequency, A a is the upper limit requirement of the error of the phasor amplitude, A φ is the upper limit requirement of the phasor phase error.

4. The method according to claim 2, characterized in that: The requirements for the quantitative indicators of response speed are: Where, ΔT k Calculate the response time for the frequency of the phasor, A r The upper limit requirement of the frequency calculation response time relative to the oscillation period, f k is the theoretical value of the phasor frequency.

5. The method according to claim 1, characterized in that The at least one constraint is: Where p(·) is the constraint condition corresponding to the broadband phasor measurement accuracy, q(·) is the constraint condition corresponding to the frequency calculation response time, and N w The length of the time window used for the measurement.

6. A novel device for measuring broadband phasors in power systems, characterized in that: include: An acquisition module is used to obtain the user's requirements for the calculation accuracy and response speed of the wide-band phasor; An integration module, for forming a frequency test set based on a plurality of frequency points for testing set in a target frequency band; A construction module, used to establish at least one constraint condition that needs to be satisfied between the frequency of the wideband phasor and the length of the time window used for measurement according to the requirement of the quantitative index; An analysis module, configured to analyze a feasible window length satisfying the constraint condition corresponding to each frequency test point in the frequency test set according to at least one constraint condition that the frequency of the established wideband phasor and the time window length need to satisfy; The measurement module is used to determine the division scheme of the target frequency range and the time window length adopted by each segment according to the feasible window length, so as to obtain the measurement result of the wideband phasor according to the division scheme and the time window length adopted by each segment.

7. The device according to claim 6, characterized in that The acquisition module comprises: A first acquisition unit is used to obtain a quantitative index requirement for the calculation accuracy of the broadband phasor according to the measurement errors of the amplitude, frequency and phase of the broadband phasor; The second acquisition unit is used to obtain the quantitative index requirement for the response speed according to the response time calculated by the phasor frequency.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a novel method for measuring wide-band phasors of a power system as described in any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement a novel method for measuring wide-band phasors of a power system as described in any one of claims 1 to 5.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the novel method for measuring wide-band phasors of a power system according to any one of claims 1 to 5.

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