New energy multi-station broadband oscillation systematic traceability method and device and electronic equipment

Abstract

The invention relates to the technical field of power systems, in particular to a new energy multi-station broadband oscillation systematized tracing method and device and electronic equipment, and the method comprises the steps: generating a topological graph of a new energy multi-station through obtaining the topological structure and electrical quantity data of the new energy multi-station, carrying out the synchronous processing and numbering of fault recording data, and obtaining a new energy multi-station broadband oscillation source; according to the method, broadband phasors of voltage of each power flow node and line current are identified, related parameters of broadband power flow are determined by combining modal power flow calculation, and finally a panorama of display equipment, power flow nodes, lines and broadband power flow parameters thereof is generated, so that accurate source tracing and positioning of broadband oscillation of new energy multi-station stations are realized, the efficiency and accuracy of oscillation source tracing are improved, and the method is suitable for popularization and application. The limitation that it is difficult to systematically analyze the oscillation problem of the whole or multiple new energy stations in the prior art is solved, and powerful support is provided for stable control and safety protection of a power system.

Description

Technical Field

[0001] This application relates to the field of power system technology, and in particular to a systematic tracing method, device and electronic equipment for broadband oscillation systems in multiple new energy power plants. Background Technology

[0002] With the continuous advancement of energy structure transformation, new energy sources, represented by wind and photovoltaic power generation, have seen a sustained increase in installed capacity and power generation share in the power system, becoming an important component of the modern power system. Accurately and quickly identifying the oscillation source after a broadband oscillation event is a crucial prerequisite for formulating effective suppression measures and preventing the escalation of the accident. Therefore, conducting source tracing research on broadband oscillations in multi-site grid-connected new energy systems has significant theoretical and engineering value. Summary of the Invention

[0003] This application provides a systematic tracing method, device, and electronic equipment for broadband oscillations at multiple new energy power plants, enabling accurate tracing and positioning of broadband oscillations at multiple new energy power plants.

[0004] The first aspect of this application provides a systematic tracing method for broadband oscillations in a multi-site renewable energy plant, comprising the following steps: acquiring the topology and electrical quantity data of the multi-site renewable energy plant, wherein the topology includes equipment, power flow nodes, and lines, and the electrical quantity data includes data of equipment, power flow nodes, and lines; generating a topology map of the multi-site renewable energy plant based on the topology, identifying fault waveform data in the electrical quantity data, numbering each fault waveform data according to the topology map, performing data synchronization processing on each numbered fault waveform data to obtain synchronization data, identifying the broadband phasors of power flow node voltages and line currents in the multi-site renewable energy plant based on the synchronization data, calculating broadband power flow related parameters of the multi-site renewable energy plant based on the power flow node voltages, line currents, and broadband phasors; generating a panoramic view of the multi-site renewable energy plant based on the broadband power flow related parameters and the topology map, and tracing the broadband oscillations of the multi-site renewable energy plant based on the panoramic view, wherein the panoramic view displays equipment, power flow nodes, lines, and broadband power flow related parameters.

[0005] Optionally, the fault recording data includes the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device's PT / CT, the recording name, start time, sampling rate, and number of sampling points.

[0006] Optionally, each fault recording data after the number is processed to obtain synchronized data, including: determining the PT / CT ratio of each corresponding line based on the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device's PT / CT; generating synchronized data of the primary side three-phase voltage and three-phase current based on the PT / CT ratio of each corresponding line; generating a summary table based on the recording name, start time, sampling rate, and number of sampling points; and selecting data from the common time periods in the summary table for time alignment and synchronization processing to obtain synchronized data.

[0007] Optionally, the broadband phasors of power flow node voltages and line currents in multiple new energy power plants are identified based on the synchronous data, including: performing discrete Fourier analysis on the synchronously processed data to obtain a spectrum; using a sliding data window to analyze the changing trend of broadband phasors over time on the spectrum; interpolating the fundamental and harmonic phasors of power flow node voltages and line currents within the synchronous time period based on the analysis results; and determining the broadband phasors of power flow node voltages and line currents based on the interpolation results.

[0008] Optionally, broadband power flow related parameters of new energy multi-stations are calculated based on power flow node voltage, line current, and broadband phasor, including: calculating the modal power of power flow nodes and lines based on the measured and estimated values ​​of broadband phasors of node voltage and line current, and determining the broadband power flow related parameters of new energy multi-stations based on power flow node voltage, line current, and modal power.

[0009] Optionally, the formula for calculating the estimated value of the broadband phasor is:

[0010] in, Y It is a coefficient matrix; λ For regularization parameters; M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Y T Coefficient matrix Y transpose, I It is an identity matrix.

[0011] Optionally, broadband power flow related parameters include the direction and amplitude of modal currents of each line, the amplitude of modal voltages of each power flow node, and the modal active and reactive power of each device.

[0012] Optionally, the broadband oscillations of multiple new energy power plants can be traced based on the panoramic view, including: identifying the modal power of each device or power plant from the panoramic view; identifying the oscillation source based on the modal power; if the modal power meets the identification criteria for the oscillation source, then the device or power plant is determined to be the oscillation source, wherein the identification criteria are:

[0013] in,, i For node or line numbering, P i For nodes / lines i The modal active power input to the power grid from the corresponding equipment or station; U i0 For nodes i The voltage fundamental phasor amplitude, I i0 For the line i The amplitude of the fundamental phasor of the current; A T1 For the preset power threshold, A T2 For the preset current threshold, A T3 The preset threshold value for the amplitude of the oscillation component. For the line i The amplitude of the current oscillation component at the oscillation frequency For nodes i The amplitude of the voltage oscillation component at the oscillation frequency.

[0014] The second aspect of this application provides a systematic tracing device for broadband oscillation systems in multiple new energy power plants, comprising: an acquisition module for acquiring the topology and electrical quantity data of the multiple new energy power plants, wherein the topology includes equipment, power flow nodes, and lines, and the electrical quantity data includes data of equipment, power flow nodes, and lines; a processing module for generating a topology map of the multiple new energy power plants based on the topology, identifying fault waveform data in the electrical quantity data, numbering each fault waveform data according to the topology map, and performing data synchronization processing on each numbered fault waveform data to obtain synchronization data; a calculation module for identifying the broadband phasors of the power flow node voltages and line currents in the multiple new energy power plants based on the synchronization data, and calculating broadband power flow related parameters of the multiple new energy power plants based on the power flow node voltages, line currents, and broadband phasors; and a tracing module for generating a panoramic view of the multiple new energy power plants based on the broadband power flow related parameters and the topology map, and tracing the broadband oscillations of the multiple new energy power plants based on the panoramic view, wherein the panoramic view displays equipment, power flow nodes, lines, and broadband power flow related parameters.

[0015] Optionally, the fault recording data includes the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device's PT / CT, the recording name, start time, sampling rate, and number of sampling points.

[0016] Optionally, the processing module is further used to perform data synchronization processing on each fault recording data after numbering to obtain synchronization data, including: determining the PT / CT ratio of each corresponding line based on the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device's PT / CT, generating synchronization data of the primary side three-phase voltage and three-phase current based on the PT / CT ratio of each corresponding line; generating a summary table based on the recording name, start time, sampling rate, and number of sampling points, and selecting data from the common time period in the summary table for time alignment and synchronization processing to obtain synchronization data.

[0017] Optionally, the calculation module is further used to perform discrete Fourier analysis on the synchronously processed data to obtain a spectrum; to analyze the trend of broadband phasors changing with time on the spectrum using a sliding data window; to perform interpolation calculations on the fundamental phasors and harmonic phasors of the voltage at each power flow node and the line current during the synchronous time period based on the analysis results; and to determine the broadband phasors of the voltage at each power flow node and the line current based on the interpolation calculation results.

[0018] Optionally, the calculation module is further used to calculate the modal power of the power flow nodes and lines based on the measured and estimated values ​​of the broadband phasors of the node voltage and line current, and to determine the broadband power flow related parameters of the new energy multi-site based on the power flow node voltage, line current and modal power.

[0019] Optionally, the formula for calculating the estimated value of the broadband phasor is:

[0020] in, Y It is a coefficient matrix; λ For regularization parameters; M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Y T Coefficient matrix Y transpose, I It is an identity matrix.

[0021] Optionally, broadband power flow related parameters include the direction and amplitude of modal currents of each line, the amplitude of modal voltages of each power flow node, and the modal active and reactive power of each device.

[0022] Optionally, the tracing module is further used to identify the modal power of each device or station from the panoramic image; and to identify the oscillation source based on the modal power. If the modal power meets the identification criteria for the oscillation source, then the device or station is determined to be an oscillation source, wherein the identification criteria are:

[0023] in, i For node or line numbering, P iFor nodes / lines i The modal active power input to the power grid from the corresponding equipment or station; U i0 For nodes i The voltage fundamental phasor amplitude, I i0 For the line i The amplitude of the fundamental phasor of the current; A T1 For the preset power threshold, A T2 For the preset current threshold, A T3 The preset threshold value for the amplitude of the oscillation component. For the line i The amplitude of the current oscillation component at the oscillation frequency For nodes i The amplitude of the voltage oscillation component at the oscillation frequency.

[0024] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes the program to implement the systematic tracing method for broadband oscillation systems of new energy multi-site stations as described in the above embodiments.

[0025] Therefore, this application has the following beneficial effects: This application embodiment acquires the topology and electrical quantity data of multiple new energy power plants, generates a topology map of the multiple new energy power plants, synchronously processes and numbers the fault recording data, identifies the broadband phasors of voltage and line current at each power flow node, and determines broadband power flow related parameters by combining modal power flow calculations. Finally, it generates a panoramic view of the display equipment, power flow nodes, lines and their broadband power flow parameters, realizing accurate tracing and positioning of broadband oscillations in multiple new energy power plants. This solves the limitation of related technologies that make it difficult to systematically analyze the oscillation problem of the entire or multiple new energy power plants, and provides strong support for the stable control and safety protection of the power system.

[0026] Additional aspects and advantages of this application 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 this application. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart illustrating a systematic tracing method for a multi-site broadband oscillation system in new energy, provided according to an embodiment of this application. Figure 2This is a topology diagram of a wind farm main transformer and its nodes and branches according to an embodiment of this application; Figure 3 This is a waveform diagram of phase A voltage data of the low-voltage side (N1) of the main transformer provided according to an embodiment of this application; Figure 4 This is a one-dimensional spectrum analysis diagram of the A-phase voltage on the low-voltage side (N1) of the main transformer according to an embodiment of this application; Figure 5 A three-dimensional spectrum diagram of the A-phase voltage on the low-voltage side (N1) of the main transformer according to an embodiment of this application; Figure 6 This is a primary-side modal power flow distribution diagram of a wind farm according to an embodiment of this application; Figure 7 This is a block diagram of a broadband oscillation system traceability device for new energy multi-sites provided according to an embodiment of this application; Figure 8 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application. Detailed Implementation

[0028] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0029] The following description, with reference to the accompanying drawings, describes a systematic tracing method, apparatus, and electronic equipment for broadband oscillations in multiple new energy power plants according to embodiments of this application. Addressing the problems mentioned in the background art, this application provides a systematic tracing method for broadband oscillations in multiple new energy power plants. In this method, by acquiring the topology and electrical quantity data of multiple new energy power plants, a topology map of the power plants is generated. Fault recording data is synchronously processed and numbered to identify the broadband phasors of voltage at each power flow node and line current. Combined with modal power flow calculations, broadband power flow related parameters are determined. Finally, a panoramic view displaying the equipment, power flow nodes, lines, and their broadband power flow parameters is generated, achieving accurate tracing and positioning of broadband oscillations in multiple new energy power plants. This improves the efficiency and accuracy of oscillation tracing, overcomes the limitations of related technologies in systematically analyzing the oscillation problems of entire or multiple new energy power plants, and provides strong support for the stable control and safety protection of power systems.

[0030] Specifically, Figure 1 The flowchart illustrates a systematic tracing method for broadband oscillation systems in multiple new energy power plants, as provided in this application embodiment.

[0031] like Figure 1As shown, the systematic source tracing method for broadband oscillation systems at multiple new energy sites includes the following steps: In step S101, the topology and electrical quantity data of the new energy multi-station are obtained. The topology includes equipment, power flow nodes and lines, and the electrical quantity data includes data of equipment, power flow nodes and lines.

[0032] It is understandable that multiple power flow nodes and branches exist within a renewable energy power station, including the high and low voltage sides of the main transformer, wind turbines, photovoltaic systems, SVG, and station service transformers. Once harmonic or interharmonic oscillations occur, the magnitude and direction of the oscillation components differ at each node and branch. Taking all factors into consideration, this application's embodiments require analyzing the active and reactive power output of each node and branch individually, analyzing the power flow direction, and further analyzing the root causes of the oscillations to provide a reference for power station stability control and safety protection.

[0033] Specifically, the embodiments of this application can obtain the basic situation of multiple new energy power stations before and after oscillation, including: (1) the electrical main wiring topology, including the main transformer high and low voltage test and the operation status of the collection line; (2) the equipment operation status, including the wind power / photovoltaic power input and operation status, SVG control mode, etc.; (3) the background parameters of the oscillation event, including the oscillation occurrence time, grid dispatch instructions, wind speed, light intensity, etc. Then, the electrical quantity data of each node and line are collected synchronously, including the transformation ratio and waveform data of all equipment such as the main transformer high and low voltage side of the new energy power station, wind turbine box transformer, photovoltaic inverter, SVG connection point, etc.

[0034] In step S102, a topology map of the new energy multi-station is generated according to the topology structure, fault recording data in the electrical quantity data is identified, each fault recording data is numbered according to the topology map, and data synchronization processing is performed on each numbered fault recording data to obtain synchronization data.

[0035] The fault recording data includes the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each PT / CT, the recording name, start time, sampling rate, and number of sampling points.

[0036] It is understood that, according to the embodiments of this application, a topology diagram conforming to the IEC 61970 standard can be drawn based on the topology of the new energy power station and the operating parameters of the station, and the various lines, nodes and transformers of the station can be numbered and the phasor reference direction can be specified.

[0037] Furthermore, each fault recording data after numbering is processed to obtain synchronized data, including: determining the PT / CT ratio of each corresponding line based on the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each equipment PT / CT; generating synchronized data of the primary side three-phase voltage and three-phase current based on the PT / CT ratio of each corresponding line; generating a summary table based on the recording name, start time, sampling rate, and number of sampling points; and selecting data from the common time periods in the summary table for time alignment and synchronization processing to obtain synchronized data.

[0038] This application embodiment can organize fault waveform data in electrical quantity data. By using the PT / CT ratio of each corresponding line, synchronous data of the effective values ​​of the primary side three-phase voltage and three-phase current are generated. Each fault waveform data is numbered with reference to the numbers of each line, node, and transformer. Key information such as waveform name, start time, sampling rate, and number of sampling points are summarized and tabulated. Data from common time periods are selected for time alignment and synchronization processing to facilitate the analysis of data from multiple lines or nodes under the same site, and also to facilitate collaborative analysis of data from multiple sites.

[0039] In step S103, broadband phasors of power flow node voltage and line current in the new energy multi-station are identified based on the synchronization data, and broadband power flow related parameters of the new energy multi-station are calculated based on the power flow node voltage, line current and broadband phasors.

[0040] Among them, broadband power flow related parameters include the direction and amplitude of modal currents of each line, the amplitude of modal voltages of each power flow node, and the modal active power and reactive power of each device.

[0041] In one embodiment of this application, the identification of broadband phasors of power flow node voltages and line currents in multiple new energy power plants based on synchronization data includes: performing discrete Fourier analysis on the synchronized data to obtain a spectrum; using a sliding data window to analyze the changing trend of broadband phasors over time on the spectrum; interpolating the fundamental and harmonic phasors of power flow node voltages and line currents within the synchronization time period based on the analysis results; and determining the broadband phasors of power flow node voltages and line currents based on the interpolation results.

[0042] Specifically, embodiments of this application can perform a discrete Fourier transform on the synchronized data after time alignment and synchronization processing to obtain its amplitude-frequency characteristics in the frequency domain and generate a spectrum. The spectrum can visually display the trend of the amplitude of a specific frequency component changing over time, determining whether it exhibits growth, decay, or steady-state oscillation characteristics, thereby confirming the development process and stability of the oscillation.

[0043] Furthermore, in this embodiment, based on the dominant oscillation frequency (e.g., 1649Hz) determined by the above-mentioned spectral analysis, the interpolated discrete Fourier transform (IpDFT) algorithm can be used to accurately calculate the fundamental phasors and (inter)harmonic phasors of the voltage and line current at each power flow node. This can accurately identify the fundamental and harmonic components in the voltage and current, improving the accuracy of oscillation source identification. The interpolated DFT algorithm can employ methods such as three-peak interpolation or five-peak interpolation.

[0044] Next, state estimation is performed on the unmonitored bus voltage / line current in the system. That is, at an oscillation frequency of... f s In the modal context, the measured bus voltage and line current phasor data are used as inputs for state estimation to estimate the phasor data of the unmonitored bus voltage / line current. To avoid instability or overfitting caused by measurement errors, ridge regression can be used for estimation, i.e.:

[0045] in: E r A vector representing the errors of the state estimation; U The state vector is composed of node voltage phasors; Y The coefficient matrix is ​​composed of the node locations where the measuring device is installed and the network node admittance matrix at the oscillation frequency. M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Indicates the squared error; λ As a regularization parameter, it can be determined by using historical data of the monitored system for cross-validation, such as K-fold cross-validation, to identify the parameter with the best generalization ability. ， Obtain the state vector U The analytical solution is:

[0046] in, Y It is a coefficient matrix; λ For regularization parameters; M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Y T Coefficient matrix Y transpose, I It is an identity matrix.

[0047] Finally, in this embodiment, the voltage and current phasor calculation results of all monitoring points at the target frequency are summarized to form a broadband phasor dataset containing the voltage phasors of each node and the current phasors of each branch. This dataset serves as the basic input for subsequent broadband phasor state estimation and modal power flow calculation, used to assess its impact on the system. Thus, accurate identification and quantification of broadband oscillation components in a multi-site renewable energy system are achieved, laying a data foundation for constructing a systematic panoramic view of oscillation power flow.

[0048] In one embodiment of this application, the broadband power flow related parameters of the new energy multi-station are calculated based on the power flow node voltage, line current and broadband phasor, including: calculating the modal power of the power flow node and the line based on the measured and estimated values ​​of the broadband phasor of the node voltage and the line current, and determining the broadband power flow related parameters of the new energy multi-station based on the power flow node voltage, line current and modal power.

[0049] It is understood that the embodiments of this application can calculate the modal active power and reactive power of each device and line by combining the measured and estimated values ​​of the broadband phasors of node voltage and line current. Then, based on the drawn single-line diagram of the new energy power station, broadband power flow related parameters are marked, including the direction and amplitude of the modal current of each branch, the amplitude of the modal voltage of each node, and the modal active power and reactive power output of each device.

[0050] In step S104, a panoramic view of the new energy multi-station is generated based on broadband power flow related parameters and topology map. The broadband oscillation of the new energy multi-station is traced based on the panoramic view. The panoramic view displays equipment, power flow nodes, lines and broadband power flow related parameters.

[0051] In one embodiment of this application, the broadband oscillation of multiple new energy power plants is traced based on a panoramic view, including: identifying the modal power of each device or power plant from the panoramic view; identifying the oscillation source based on the modal power; and determining the device or power plant as the oscillation source if the modal power meets the identification criteria of the oscillation source.

[0052] Based on the modal power of each device or station, it is determined whether it is an oscillation source. If the following criteria are met, it is considered to be the oscillation source of this oscillation event. In this way, the accurate location of broadband oscillations in new energy power stations can be achieved, and the timeliness can also meet the needs of on-site fault handling. The specific criteria are as follows:

[0053] in, i For node or line numbering, P i For nodes / lines i The modal active power input to the power grid from the corresponding equipment or station; U i0 For nodes iThe voltage fundamental phasor amplitude, I i0 For the line i The amplitude of the fundamental phasor of the current; A T1 For the preset power threshold, A T2 For the preset current threshold, A T3 The preset threshold value for the amplitude of the oscillation component. For the line i The amplitude of the current oscillation component at the oscillation frequency For nodes i The amplitude of the voltage oscillation component at the oscillation frequency. In this criterion, the first criterion is used to determine whether the device outputs modal active power to the system; the second criterion is used to determine whether the device is in normal operation; and the third criterion is used to determine whether the modal components in the device are significant.

[0054] For ease of understanding, this application will use wind farm A as an example to provide a detailed explanation of the systematic tracing method for broadband oscillation systems in multiple new energy stations described above, as follows: Step 1: Data Collection at New Energy Power Stations 330kV system: The neutral point on the high-voltage side of the main transformer is grounded via a gap, and the neutral point on the low-voltage side is grounded with a small resistor (202Ω). All protections are correctly activated.

[0055] 35kV system: 35kV I II III busbars are operating in parallel; #1 and #2 SVG are operating; 12 wind power collection lines are operating; 2 photovoltaic feeders are operating; 1 energy storage feeder is operating.

[0056] Station service transformer system: #1 station service transformer in operation.

[0057] Weather conditions: Wind speed 2.7 m / s, temperature -15 degrees Celsius.

[0058] Status of power generation equipment: None of the 134 wind turbines in the main transformer bay of wind farm A are connected to the grid; 14 photovoltaic box-type inverter units are out of service, and 4 battery compartment PCS are on standby.

[0059] Then, electrical quantity data of each node and line are collected synchronously, including the transformation ratio and waveform data of all equipment such as the high and low voltage sides of the main transformer of the new energy power station, the wind turbine box transformer, the photovoltaic inverter, and the SVG connection point. The waveform data includes time stamps and the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each equipment's PT / CT.

[0060] Step 2: Topology mapping and data synchronization processing of new energy power stations The analysis primarily focuses on the oscillation recording data of wind farm A from 20:35:27.000 to 20:35:29.120. The recording trigger time was 20:35:27.145210, triggered by a sudden change in the #1 energy storage current. The recording duration was 2.12 seconds, the data length was 13568 points, and the sampling rate was 6400Hz.

[0061] Number each line, node, and transformer at the station, such as... Figure 2 As shown in Table 1, key information such as the file name, file start time, sampling rate, and number of sampling points of the CSV file generated from the waveform recording file are summarized.

[0062] Table 1

[0063] Step 3: Wideband Phasor Identification and State Estimation Taking the voltage of phase A on the low-voltage side (N1) of the main transformer at station A as an example, a frequency spectrum analysis (FFT) is performed: The voltage data of phase A on the low-voltage side (N1) of the main transformer was collected from the waveform recording file. The recording time was from 20:35:27.000 to 20:35:29.120, with the recording trigger time at 20:35:27.145210. The total recording time was 2.12 seconds, the data length was 13568 points, and the sampling rate was 6400Hz. The original waveform is as follows. Figure 3 As shown.

[0064] FFT analysis was performed on the waveform data from 20:35:27.000 to 20:35:29.000, and the resulting spectrum is shown below. Figure 4 As shown, during this period, the A-phase voltage of the low-voltage side (N1) of the #1 main transformer mainly contains two components with frequencies of 50Hz and 1649Hz, respectively.

[0065] Using a 1s time window for FFT analysis and a 0.01s sliding window step for sliding window analysis on the recorded waveform data, the spectral variation trend of phase A voltage on the low-voltage side (N1) of main transformer #1 during this period is obtained as follows: Figure 5 It can be seen that within 1 second, the amplitude proportion of the 1649Hz component (the ratio of its amplitude to that of the fundamental component) gradually increases from 9.38% to 36.79%.

[0066] Furthermore, in this embodiment, the fundamental phasor and the (inter-)harmonic phasor (effective values ​​of primary phase voltage and phase current) in the recorded data of each bus voltage and line current under the main transformer during the time period from 20:35:28.200 to 20:35:28.300 (time window of 0.1s) are calculated based on the three-peak interpolation DFT algorithm. The results are shown in Table 2 below.

[0067] Table 2

[0068] Step 4: Modal power flow calculation and panoramic view drawing of new energy power stations Based on the system topology, the inter-harmonic phasors of the currents of the unmonitored lines (35011, 35012, and 35013) are calculated. The oscillation power of each line in the system at 1649Hz is then calculated, yielding the oscillation distribution diagram at 1649Hz at that moment. The primary-side modal power flow distribution diagram of station A is shown below. Figure 6 As shown.

[0069] Step 5: Identification and Location of Oscillation Source Analysis of the oscillation recording data of wind farm A from 20:35:27.000 to 20:35:29.120 revealed that during this period, each node and bus under the main transformer exhibited a component of approximately 1649Hz, in addition to the power frequency, and the amplitude of this component continuously increased during this time period. Calculation and analysis of the (inter-)harmonic phasors and power near 1649Hz in the voltage and line current of each bus under the main transformer from 20:35:28.200 to 20:35:28.300 determined that #1SVG(3511) and #2SVG(3512) were the active power sources dominating this oscillation event.

[0070] The systematic source tracing method for broadband oscillations in multiple new energy power plants proposed in this application obtains the topology and electrical quantity data of the multiple new energy power plants, generates a topology map of the multiple new energy power plants, synchronously processes and numbers the fault recording data, identifies the broadband phasors of voltage and line current at each power flow node, and determines the relevant parameters of broadband power flow by combining modal power flow calculation. Finally, a panoramic view of the equipment, power flow nodes, lines and their broadband power flow parameters is generated, realizing accurate source tracing and positioning of broadband oscillations in multiple new energy power plants, improving the efficiency and accuracy of oscillation source tracing, and solving the limitation of related technologies that make it difficult to systematically analyze the oscillation problems of the entire or multiple new energy power plants. This provides strong support for the stable control and safety protection of the power system.

[0071] Secondly, referring to the accompanying drawings, the systemic traceability device for broadband oscillation of new energy multi-sites proposed according to the embodiments of this application is described.

[0072] Figure 7 This is a block diagram of a new energy multi-site broadband oscillation system traceability device according to an embodiment of this application.

[0073] like Figure 7 As shown, the new energy multi-site broadband oscillation system traceability device 10 includes: an acquisition module 100, a processing module 200, a calculation module 300, and a traceability module 400.

[0074] The system comprises the following modules: an acquisition module 100, which acquires the topology and electrical quantity data of the new energy multi-station; a processing module 200, which generates a topology map of the new energy multi-station based on the topology map, identifies fault waveform data in the electrical quantity data, assigns a number to each fault waveform data according to the topology map, and performs data synchronization processing on each numbered fault waveform data to obtain synchronization data; a calculation module 300, which identifies the broadband phasors of the voltage of the power flow nodes and the line current in the new energy multi-station based on the synchronization data, and calculates the broadband power flow related parameters of the new energy multi-station based on the voltage of the power flow nodes, the line current, and the broadband phasors; and a tracing module 400, which generates a panoramic view of the new energy multi-station based on the broadband power flow related parameters and the topology map, and traces the broadband oscillations of the new energy multi-station based on the panoramic view, which displays the equipment, power flow nodes, lines, and broadband power flow related parameters.

[0075] In one embodiment of this application, the fault recording data includes the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device's PT / CT, the recording name, the start time, the sampling rate, and the number of sampling points.

[0076] In one embodiment of this application, the processing module 200 is further configured to perform data synchronization processing on each fault recording data after numbering to obtain synchronization data, including: determining the PT / CT ratio of each corresponding line based on the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each device PT / CT; generating synchronization data of the primary side three-phase voltage and three-phase current based on the PT / CT ratio of each corresponding line; generating a summary table based on the recording name, start time, sampling rate and number of sampling points; and selecting data in the common time period in the summary table for time alignment and synchronization processing to obtain synchronization data.

[0077] In one embodiment of this application, the calculation module 300 is further used to perform discrete Fourier analysis on the synchronously processed data to obtain a spectrum; to use a sliding data window to analyze the trend of broadband phasors changing with time on the spectrum; to perform interpolation calculation on the fundamental phasors and harmonic phasors of the voltage at each power flow node and the line current during the synchronous time period based on the analysis results; and to determine the broadband phasors of the voltage at each power flow node and the line current based on the interpolation calculation results.

[0078] In one embodiment of this application, the calculation module 300 is further configured to calculate the modal power of the power flow node and the line based on the measured and estimated values ​​of the broadband phasors of the node voltage and the line current, and to determine the broadband power flow related parameters of the new energy multi-site based on the power flow node voltage, the line current and the modal power.

[0079] In one embodiment of this application, the formula for calculating the estimated value of the broadband phasor is as follows:

[0080] in, Y It is a coefficient matrix; λ For regularization parameters; M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Y T Coefficient matrix Y transpose, I It is an identity matrix.

[0081] In one embodiment of this application, broadband power flow related parameters include the direction and amplitude of the modal current of each line, the amplitude of the modal voltage of each power flow node, and the modal active power and reactive power of each device.

[0082] In one embodiment of this application, the tracing module 400 is further configured to identify the modal power of each device or station from the panoramic image; identify the oscillation source based on the modal power; if the modal power meets the identification criteria for the oscillation source, then the device or station is determined to be an oscillation source, wherein the identification criteria are:

[0083] in, i For node or line numbering, P i For nodes / lines i The modal active power input to the power grid from the corresponding equipment or station; U i0 For nodes i The voltage fundamental phasor amplitude, I i0 For the line i The amplitude of the fundamental phasor of the current; A T1 For the preset power threshold, A T2 For the preset current threshold, A T3 The preset threshold value for the amplitude of the oscillation component. For the line i The amplitude of the current oscillation component at the oscillation frequency For nodes i The amplitude of the voltage oscillation component at the oscillation frequency.

[0084] It should be noted that the explanation of the above-mentioned embodiment of the systemic tracing method for broadband oscillation of new energy multi-sites also applies to the systemic tracing device for broadband oscillation of new energy multi-sites in this embodiment, and will not be repeated here.

[0085] The systematic tracing device for broadband oscillations in multiple new energy power plants proposed in this application acquires the topology and electrical quantity data of the multiple new energy power plants, generates a topology map of the multiple new energy power plants, synchronously processes and numbers the fault recording data, identifies the broadband phasors of voltage and line current at each power flow node, and determines the relevant parameters of broadband power flow by combining modal power flow calculation. Finally, a panoramic view of the display equipment, power flow nodes, lines and their broadband power flow parameters is generated, realizing accurate tracing and positioning of broadband oscillations in multiple new energy power plants, improving the efficiency and accuracy of oscillation tracing, and solving the limitation of related technologies that make it difficult to systematically analyze the oscillation problems of the entire or multiple new energy power plants. This provides strong support for the stable control and safety protection of the power system.

[0086] Figure 8 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include: The memory 801, the processor 802, and the computer program stored on the memory 801 and capable of running on the processor 802.

[0087] When the processor 802 executes the program, it implements the systematic tracing method for broadband oscillation systems of new energy multi-sites provided in the above embodiments.

[0088] Furthermore, electronic devices also include: Communication interface 803 is used for communication between memory 801 and processor 802.

[0089] The memory 801 is used to store computer programs that can run on the processor 802.

[0090] The memory 801 may include high-speed RAM (Random Access Memory) memory, and may also include non-volatile memory, such as at least one disk storage.

[0091] If the memory 801, processor 802, and communication interface 803 are implemented independently, then the communication interface 803, memory 801, and processor 802 can be interconnected via a bus to complete communication between them. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 8 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0092] Optionally, in a specific implementation, if the memory 801, processor 802, and communication interface 803 are integrated on a single chip, then the memory 801, processor 802, and communication interface 803 can communicate with each other through an internal interface.

[0093] The processor 802 may be a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of this application.

[0094] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described systematic tracing method for broadband oscillation systems in multiple new energy power stations.

[0095] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0096] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0097] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0098] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any of the following techniques known in the art, or a combination thereof: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (FPGAs), field-programmable gate arrays (FPGAs), etc.

[0099] Those skilled in the art will understand that all or part of the steps of the methods implementing the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0100] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A systematic source tracing method for broadband oscillation systems at multiple new energy sites, characterized in that, Includes the following steps: The topology and electrical quantity data of multiple new energy power stations are acquired, wherein the topology includes equipment, power flow nodes and lines, and the electrical quantity data includes data of equipment, power flow nodes and lines; A topology map of the new energy multi-site is generated based on the topology structure, fault recording data in the electrical quantity data is identified, each fault recording data is numbered according to the topology map, and data synchronization processing is performed on each numbered fault recording data to obtain synchronization data. Based on the synchronous data, the broadband phasors of the power flow node voltage and line current in the new energy multi-power station are identified, and the broadband power flow related parameters of the new energy multi-power station are calculated based on the power flow node voltage, the line current and the broadband phasor. A panoramic view of the new energy multi-site is generated based on the broadband power flow related parameters and the topology map. The broadband oscillation of the new energy multi-site is traced based on the panoramic view. The panoramic view displays the equipment, the power flow nodes, the lines and the broadband power flow related parameters.

2. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 1, characterized in that, The fault recording data includes the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each PT / CT, the recording name, start time, sampling rate, and number of sampling points.

3. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 2, characterized in that, The process of synchronizing each fault waveform data after numbering to obtain synchronized data includes: Based on the instantaneous values ​​of the three-phase voltage and three-phase current on the secondary side of each PT / CT, the PT / CT ratio of each corresponding line is determined, and synchronous data of the three-phase voltage and three-phase current on the primary side is generated based on the PT / CT ratio of each corresponding line. A summary table is generated based on the waveform name, the start time, the sampling rate, and the number of sampling points. Data from common time periods in the summary table are selected and time-aligned for synchronization to obtain synchronized data.

4. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 1, characterized in that, The step of identifying the broadband phasors of the power flow node voltages and line currents in the new energy multi-stations based on the synchronization data includes: The spectrum is obtained by performing discrete Fourier analysis on the synchronously processed data; The trend of broadband phasors changing over time on the spectrum was analyzed using a sliding data window. Based on the analysis results, the fundamental phasors and harmonic phasors of the voltage and line current of each power flow node within the synchronization time period are interpolated and calculated. Based on the interpolation results, the broadband phasors of the voltage and line current of each power flow node are determined.

5. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 1, characterized in that, The calculation of broadband power flow related parameters for the new energy multi-site based on the power flow node voltage, the line current, and the broadband phasor includes: Based on the measured and estimated values ​​of the broadband phasors of the node voltage and line current, the modal power of the power flow node and line is calculated, and the broadband power flow related parameters of the new energy multi-site are determined based on the power flow node voltage, the line current and the modal power.

6. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 5, characterized in that, The formula for calculating the estimated value of the broadband phasor is as follows: in, Y It is a coefficient matrix; λ For regularization parameters; M The observation vector is composed of the voltage phasor of the monitored bus and the current phasor of the monitored line. Y T Coefficient matrix Y transpose, I It is an identity matrix.

7. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 5, characterized in that, The broadband power flow related parameters include the direction and amplitude of the modal current of each line, the amplitude of the modal voltage of each power flow node, and the modal active power and reactive power of each device.

8. The systematic source tracing method for broadband oscillation systems at multiple new energy sites according to claim 1, characterized in that, The process of tracing the broadband oscillations of the multiple new energy power stations based on the panoramic view includes: Identify the modal power of each device or station from the panoramic image; The oscillation source is identified based on the modal power. If the modal power meets the identification criteria for the oscillation source, then the device or site is determined to be an oscillation source. The identification criteria are: in, i For node or line numbering, P i For nodes / lines i The modal active power input to the power grid from the corresponding equipment or station; U i0 For nodes i The voltage fundamental phasor amplitude, I i0 For the line i The amplitude of the fundamental phasor of the current; A T1 For the preset power threshold, A T2 For the preset current threshold, A T3 The preset threshold value for the amplitude of the oscillation component. For the line i The amplitude of the current oscillation component at the oscillation frequency For nodes i The amplitude of the voltage oscillation component at the oscillation frequency.

9. A systematic traceability device for a multi-site broadband oscillation system in new energy, characterized in that, include: The acquisition module is used to acquire the topology and electrical quantity data of multiple new energy power stations, wherein the topology includes equipment, power flow nodes and lines, and the electrical quantity data includes data of equipment, power flow nodes and lines; The processing module is used to generate a topology map of the new energy multi-station based on the topology structure, identify fault waveform data in the electrical quantity data, number each fault waveform data according to the topology map, and perform data synchronization processing on each numbered fault waveform data to obtain synchronization data. The calculation module is used to identify the broadband phasors of the power flow node voltage and line current in the new energy multi-station based on the synchronization data, and to calculate the broadband power flow related parameters of the new energy multi-station based on the power flow node voltage, the line current and the broadband phasor; The tracing module is used to generate a panoramic view of the new energy multi-site based on the broadband power flow related parameters and the topology map, and to trace the broadband oscillation of the new energy multi-site based on the panoramic view. The panoramic view displays the equipment, the power flow nodes, the lines and the broadband power flow related parameters.

10. 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 the systematic tracing method for broadband oscillation systems of new energy multi-sites as described in any one of claims 1-8.

Images