ADPSS-based new energy model impedance sweep method, power grid stability analysis method, storage medium and equipment

Abstract

This invention relates to the field of power technology and includes an impedance frequency sweep method for new energy models, a power grid stability analysis method, storage media, and equipment based on ADPSS. It addresses the current lack of automated frequency sweep technology specifically for new energy black-box models. The invention establishes a harmonic signal generation module using ADPSS software. The input of this module records the three-phase voltage and current at the frequency sweep test points, while its output generates a time-varying disturbance frequency signal to simulate the injection of harmonic disturbance signals into the power grid. Simulations are performed, and the response signals during the frequency sweep are recorded and stored. Based on software capable of numerical calculation and analysis, the impedance of the new energy black-box model is calculated. Furthermore, the positive-sequence and negative-sequence impedances of the new energy black-box model, taking into account grid interactions, are calculated, and the stability margin of the new energy black-box model is calculated, thus achieving power grid stability analysis.

Description

Technical Field

[0001] This invention belongs to the field of power technology and relates to impedance frequency sweep method for power system new energy power generation equipment model and power grid stability analysis method, as well as corresponding storage media and equipment. Background Technology

[0002] With the continuous expansion of my country's installed capacity of new energy sources and the development trend of high-proportion new energy grid connection, the proportion of new energy sources such as wind power and photovoltaics in the power system is constantly increasing. Their operating characteristics are gradually having a significant impact on the voltage stability, frequency stability, and resonance characteristics of the power grid. New energy grid-connected converters are essentially power electronic devices, and their dynamic behavior is closely related to their impedance characteristics. When there is a high grid impedance near the new energy source's grid connection point or when it is coupled with other converters, the system is prone to stability problems such as resonance and oscillation. Therefore, conducting accurate and comprehensive analysis of the impedance characteristics of new energy models is an important technical means to ensure the safe and stable operation of the power grid.

[0003] Electromagnetic transient simulation technology is a crucial foundation for studying the dynamic characteristics of new energy systems. Currently, major new energy equipment manufacturers develop and provide electromagnetic simulation models for their equipment based on the ADPSS platform. However, these models employ encapsulated or black-box structures, making it difficult to obtain internal control parameters and directly acquire their dynamic characteristics through analytical modeling. This poses significant challenges to the analysis and verification of the impedance characteristics of new energy equipment.

[0004] In the theory of new energy stability, impedance models are crucial for analyzing grid-connected interaction characteristics, identifying system resonant points, and evaluating grid stability. Lacking internal model information, external frequency sweep techniques must be relied upon to calculate the system's small-signal impedance by applying perturbations to the model and measuring the response. However, current ADPSS platforms lack robust impedance frequency sweep methods and automated frequency sweep techniques specifically designed for new energy black-box models, making it difficult for simulation engineers to efficiently, accurately, and quantitatively obtain the impedance characteristics of equipment.

[0005] Therefore, there is an urgent need to develop an impedance frequency sweep method for the ADPSS platform and applicable to new energy black-box models. This method should be able to obtain the positive and negative sequence impedance characteristics of grid-connected converters through simulation disturbance injection and response analysis without damaging the model packaging structure or relying on the manufacturer's internal parameters. This will support the stability analysis and system evaluation of grids with a high proportion of new energy. Summary of the Invention

[0006] This invention aims to address the current lack of automated frequency sweeping technology specifically designed for new energy black-box models.

[0007] An impedance frequency sweep method for new energy models based on ADPSS, comprising:

[0008] S1. Establish a harmonic signal generation module using ADPSS software. The input of the harmonic signal generation module is used to record the three-phase voltage and current at the frequency sweep test point, and its output is used to generate a disturbance frequency signal that varies with time, simulating the injection of harmonic disturbance signals into the power grid. Set the harmonic phase sequence of the harmonic signal generation module to positive and negative, and perform subsequent processing once for each.

[0009] S2. Connect the harmonic voltage reference signal generated by the harmonic signal generation module to the controlled voltage source of the simulated power grid module of the new energy black box model to be swept, perform simulation, and record and store the response signal during the frequency sweep operation.

[0010] S3. Extract the sweep frequency data, including input and output data, and import it into software capable of numerical calculation and numerical analysis;

[0011] S4. Calculate the impedance of the new energy black-box model, including the positive-sequence admittance. and positive-sequence coupling admittance and negative order admittance and negative order coupling admittance This enables the calculation of the impedance model for the new energy black box model.

[0012] Furthermore, when setting up the harmonic signal generation module, the disturbance frequency is divided into multiple frequency ranges, and different frequency step sizes are set in different frequency ranges, thereby realizing the generation of wide-band, multi-resolution sweeping disturbance signals.

[0013] Furthermore, the specific process of step S2 includes:

[0014] The three-phase voltage signals at the impedance calculation point are connected to the input ports Ua, Ub, and Uc of the harmonic signal generation module, and the corresponding three-phase current signals are connected to the input ports Ia, Ib, and Ic. Before the simulation runs, the three-phase voltage and three-phase current response data under the action of the harmonic signal generation module are automatically stored in the working directory of the model and corresponding data files are generated. The input data file records the three-phase voltage and current data at the input of the harmonic signal generation module, and the output data file records the harmonic voltage command signal and disturbance frequency data output by the harmonic signal generation module.

[0015] Furthermore, in step S4, the impedance calculation of the new energy black box model is divided into positive-sequence impedance measurement and negative-sequence impedance measurement.

[0016] The formula for calculating positive sequence impedance is as follows:

[0017] Based on the harmonic phase sequence setting of the harmonic signal generation module to positive corresponding data, the harmonic signal generation module injects a frequency of [frequency value missing] into the ADPSS simulation model corresponding to the new energy black box model. The positive-sequence voltage disturbance component is extracted by performing a Fourier transform on the extracted three-phase voltage and current data. and positive sequence current response components And calculate the positive-sequence admittance. ;

[0018] when At that time, extract the positive sequence current response component. According to its complex conjugate form and Calculate positive-sequence coupling admittance Or when At that time, extract the negative sequence current response component. and combined Calculate positive-sequence coupling admittance ;

[0019] The formula for calculating negative sequence impedance is as follows:

[0020] Based on the harmonic phase sequence setting of the harmonic signal generation module to the negative corresponding data, the frequency is injected into the ADPSS simulation model corresponding to the new energy black box model through the harmonic signal generation module. Negative sequence voltage disturbance;

[0021] when At that time, extract the positive sequence voltage disturbance component. Positive sequence current response component and positive sequence current response components ,according to The complex conjugate form and Calculating the negative order admittance in the complex conjugate form and according to and Calculate the negative-order coupling admittance using the complex conjugate form. ;

[0022] Or, when At that time, the negative sequence voltage disturbance component is extracted. Extracting the negative sequence current response component and positive sequence current response components ,according to and Calculate negative-order admittance ,according to and Calculate negative-order coupling admittance .

[0023] A computer storage medium storing at least one instruction, which is loaded and executed by a processor to implement the impedance sweep frequency method for a new energy model based on ADPSS.

[0024] An impedance sweep frequency device for a new energy model based on ADPSS is disclosed. The device includes a processor and a memory. The memory stores at least one instruction, which is loaded and executed by the processor to implement the impedance sweep frequency method for a new energy model based on ADPSS.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] By implementing disturbance injection and response measurement of the new energy black box model in the ADPSS platform, the impedance characteristics of the model can be accurately obtained without obtaining the manufacturer's internal control parameters, realizing the effective external characteristic analysis of the packaged model; the simulation data is flexibly extracted using MATLAB, which can support various forms of subsequent programming calculations and automated processing, and has good scalability and operability.

[0027] This invention also provides a grid stability analysis method based on impedance frequency sweep of a renewable energy model using ADPSS. The impedance of the renewable energy black-box model, including the positive-sequence admittance, is obtained according to the aforementioned ADPSS-based impedance frequency sweep method. and positive-sequence coupling admittance and negative order admittance and negative order coupling admittance Power grid stability analysis is performed based on impedance obtained from frequency sweep, including:

[0028] The grid impedance is swept using a frequency sweep and calculated. A stability criterion is used to determine if there is a risk of resonance between the renewable energy source and the grid. During the grid impedance sweep and calculation process, the positive sequence impedance scanning method is as follows:

[0029] The new energy black box model and the simulated power grid module were disconnected. A frequency of [frequency value missing] was injected into the new energy black box model, which only contains the simulated power grid module, through the harmonic signal generation module. The positive-sequence current disturbance is used to perform a Fourier transform on the extracted three-phase voltage and current data to extract the positive-sequence voltage response component. and positive sequence current disturbance component And calculate the positive-sequence admittance of the power grid. ;

[0030] when At that time, extract the positive sequence current response component. According to its complex conjugate form and Calculate the positive-sequence coupling admittance of the power grid Or, when At that time, extract the negative sequence current response component. , combined Calculate positive-sequence coupling admittance ;

[0031] During the process of frequency sweeping and calculating the grid impedance, the negative sequence impedance scanning method is as follows:

[0032] Injecting frequencies into the ADPSS power grid model through disturbance sources Negative sequence current disturbance;

[0033] when Extracting the positive sequence voltage response component Positive sequence current disturbance component and positive sequence current response components ,according to The complex conjugate form and Calculating negative order admittance using the conjugate form of the number ,according to and Calculate the negative-order coupling admittance using the conjugate form of the numbers. Or, when At that time, extract the negative sequence voltage response component. Extracting the negative sequence current disturbance component and positive sequence current response components ,according to and Calculate negative-order admittance ,according to and Calculate negative-order coupling admittance ;

[0034] The stability criterion is used to determine whether there is a resonance risk between the new energy black-box model and the power grid. The stability criterion is as follows:

[0035] Positive sequence impedance of a new energy black-box model considering grid interaction and negative sequence impedance According to the positive sequence admittance of the power grid Calculate the positive sequence impedance of the power grid And thus obtain Positive sequence impedance as a stability criterion for new energy black-box models positive sequence impedance ratio According to the negative sequence admittance of the power grid Calculate the negative sequence impedance of the power grid And thus obtain Negative sequence impedance, a stability criterion for new energy black-box models negative sequence impedance ratio Determine the positive sequence impedance ratio and negative sequence impedance Compare whether the Nyquist stability criterion is satisfied to calculate the stability margin of the new energy black-box model. This enables power grid stability analysis.

[0036] Furthermore, the positive sequence impedance of the new energy black-box model, which takes into account grid interaction, is calculated. and negative sequence impedance as follows:

[0037] (17)

[0038] (18).

[0039] A computer storage medium storing at least one instruction, which is loaded and executed by a processor to implement the aforementioned method for power grid stability analysis based on impedance sweep frequency of a new energy model using ADPSS.

[0040] A power grid stability analysis device based on impedance frequency sweep of a renewable energy model using ADPSS is disclosed. The device includes a processor and a memory. The memory stores at least one instruction, which is loaded and executed by the processor to implement the aforementioned power grid stability analysis method based on impedance frequency sweep of a renewable energy model using ADPSS.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] This invention enables further comparative analysis between the impedance of new energy sources and the grid impedance after obtaining the impedance. By using the impedance ratio stability criterion, the risk of grid resonance can be determined, providing a reliable basis for the stability assessment of new energy grid-connected systems, grid planning and operation, and has significant engineering application value. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the process of the present invention;

[0044] Figure 2 This is a schematic diagram of a harmonic signal generation module;

[0045] Figure 3 Set up a model diagram for the disturbance power source;

[0046] Figure 4 The parameter setting interface for the harmonic signal generation module;

[0047] Figure 5 This is the interface for selecting output parameters of the harmonic signal generation module.

[0048] Figure 6 This serves as the stability criterion for the new energy black-box model of the present invention. Detailed Implementation

[0049] This invention addresses the shortcomings of existing ADPSS-based electromagnetic transient models for new energy sources, which typically employ black-box encapsulation, making it impossible to directly obtain internal control parameters and hindering impedance characteristic analysis. Furthermore, these models lack flexible frequency sweeping techniques. This invention provides an impedance frequency sweeping method for new energy black-box models based on ADPSS. This method enables automatic injection of disturbance signals, flexible extraction of response data, and impedance calculation, significantly improving the engineering applicability and flexibility of impedance analysis for new energy black-box models. The specific implementation method is described below. It should be noted that while this embodiment focuses on impedance frequency sweeping for new energy black-box models, this invention is also applicable to impedance frequency sweeping of new energy models with known structures, using the same processing method, and will not be repeated here.

[0050] Combination Figure 1 This embodiment first describes an impedance frequency sweep method for a new energy model based on ADPSS, which includes:

[0051] S1. Parameter settings for the harmonic signal generation module:

[0052] First, a harmonic signal generation module was created in DLL form using the custom UD plugin function of the ADPSS software, and its parameters were set. The harmonic signal generation module, in accordance with the national standard requirements for impedance sweep frequency testing of new energy sources, divides the disturbance frequency into multiple frequency ranges and sets different frequency step sizes within each range, thereby achieving wide-band, multi-resolution sweep disturbance signal generation.

[0053] In this embodiment, the structure of the harmonic signal generation module is shown in the diagram below. Figure 2 As shown, its input terminal is used to record the three-phase voltage and current at the frequency sweep test point, and its output terminal is used to generate a time-varying disturbance frequency signal. The disturbance frequency signal at the output terminal controls the output frequency and amplitude of the controlled voltage source, simulating the injection of harmonic disturbance signals into the power grid. The model setup method of the controlled voltage source is as follows: Figure 3 As shown.

[0054] The parameter setting interface of the harmonic signal generation module is as follows: Figure 4As shown, fbase represents the fundamental frequency, AmpBase represents the fundamental amplitude, AmpHar represents the harmonic amplitude, Tstart represents the harmonic injection start time, fstart represents the harmonic start frequency, df1 represents the frequency step size of the first frequency range, fre1 represents the first intermediate frequency, df2 represents the frequency step size of the second frequency range, fre2 represents the second intermediate frequency, df3 represents the frequency step size of the third frequency range, fend represents the harmonic termination frequency, fhold represents the duration of a single frequency, and seq represents the phase sequence of the harmonic signal. In this embodiment, the specific parameter settings are as follows: fundamental frequency is 50Hz, fundamental amplitude AmpBase is 1p.u., harmonic amplitude AmpHar is 0.02pu, harmonic injection start time Tstart is 2.5s, harmonic start frequency fstart is 2Hz, first frequency band frequency interval df1 is 1Hz, first intermediate frequency fre1 is 200Hz; second frequency band frequency interval df2 is 5Hz, second intermediate frequency fre2 is 400Hz; third frequency band frequency interval df3 is 10Hz, harmonic termination frequency fend is 1000Hz, single frequency duration fhold is 1s, and harmonic phase sequence seq is 1, indicating positive sequence. After completing the above parameter settings, a harmonic signal generation model for frequency sweep perturbation injection can be formed.

[0055] Will Figure 4 In the parameter setting interface of the middle harmonic signal generator module, set "seq" to "1" to perform one subsequent processing (recording three-phase voltage and current response data); Figure 4 In the parameter setting interface of the middle harmonic signal generation module, set "seq" to "-1" to perform a subsequent processing.

[0056] S2. Perform frequency sweep operation and record three-phase voltage and current response data:

[0057] After completing the frequency sweep signal setting in step S1, connect the harmonic voltage reference signal generated by the harmonic signal generation module to the controlled voltage source of the simulated power grid module of the new energy black box model to be swept, click the simulation run button to perform model simulation, and record and store the response signal during the frequency sweep operation.

[0058] Specifically, the three-phase voltage signals at the impedance calculation points are connected to the input ports Ua, Ub, and Uc of the harmonic signal generation module, and the corresponding three-phase current signals are connected to the input ports Ia, Ib, and Ic. Before the simulation runs, the output parameter page signal is selected, such as... Figure 5As shown, the three-phase voltage and three-phase current response data under the action of the harmonic signal generation module are automatically stored in the model's working directory, generating corresponding txt format data files, including "HarmSweepDLLinput.txt" and "HarmSweepDLLoutput.txt". "HarmSweepDLLinput.txt" records the three-phase voltage and current data at the input of the harmonic signal generation module, while "HarmSweepDLLoutput.txt" records the harmonic voltage command signal and disturbance frequency data output by the harmonic signal generation module.

[0059] Step S2 allows for the unified recording of voltage and current response data at each disturbance frequency point during the frequency sweep process without affecting the frequency sweep signal generation method, providing a source of raw data for subsequent data extraction and impedance calculation.

[0060] S3. Extract the sweep frequency data and import it into MATLAB:

[0061] After completing step S2, a MATLAB program was used to extract voltage and current data at the disturbance frequency points. This program was then used to extract the input and output data "HarmSweepDLLinput.txt" and "HarmSweepDLLoutput.txt" from the harmonic signal generation module, which were automatically generated and stored in the working directory of the new energy black box frequency sweeping module during step S2. Figure 1 The data is read from the data files recorded at the input and output terminals of the harmonic signal generation module. The main function of this data processing program is to import the data from the txt file into the MATLAB workspace using the "readtable" function statement, and to break down the disturbance voltage and current data for different frequency ranges according to the frequency command signal output by "HarmSweepDLLoutput.txt", so as to facilitate the calculation of impedance models at different frequencies.

[0062] Specifically, the MATLAB program locates the working directory of the new energy black box frequency sweep, parses the data structure in the txt file, extracts the three-phase voltage data, three-phase current data and disturbance frequency signal corresponding to each disturbance frequency point during the frequency sweep process, and organizes them into the data format required for impedance calculation, providing data input for the subsequent impedance calculation and stability analysis of the new energy black box model of frequency sweep.

[0063] S4. Impedance Calculation of New Energy Black-Box Model:

[0064] The impedance of the new energy black-box model is calculated according to national standards and expressed in the form of a 2*2 admittance matrix. The impedance calculation of the new energy black-box model is divided into positive-sequence impedance measurement and negative-sequence impedance measurement.

[0065] The formula for calculating positive sequence impedance is as follows:

[0066] Based on the data corresponding to "seq" being set to "1" in the parameter setting interface of the harmonic signal generation module, the harmonic signal generation module injects a frequency of [frequency value missing] into the ADPSS simulation model corresponding to the new energy black box model. The positive-sequence voltage disturbance component is extracted by performing a Fourier transform on the extracted three-phase voltage and current data. and positive sequence current response components The positive-sequence admittance is calculated using formula (1). :

[0067] (1)

[0068] when At that time, extract the positive sequence current response component. The positive-sequence coupling admittance is calculated using formula (2). :

[0069] (2)

[0070] In the formula: This is the fundamental frequency, which is set to 50Hz in this embodiment; It is the conjugate of complex numbers.

[0071] when At that time, extract the negative sequence current response component. The positive-sequence coupling admittance is calculated using formula (3). :

[0072] (3)

[0073] The formula for calculating negative sequence impedance is as follows:

[0074] Based on the data corresponding to setting "seq" to "-1" in the parameter setting interface of the harmonic signal generator module, the frequency is injected into the ADPSS simulation model corresponding to the new energy black box model through the harmonic signal generator module. Negative sequence voltage disturbance;

[0075] when At that time, extract the positive sequence voltage disturbance component. Positive sequence current response component and positive sequence current response components The negative-order admittance is calculated using formula (4). The negative-order coupling admittance is calculated using formula (5). :

[0076] (4)

[0077] (5)

[0078] when At that time, the negative sequence voltage disturbance component is extracted. Extracting the negative sequence current response component and positive sequence current response components The negative-order admittance is calculated using formula (6). The negative-order coupling admittance is calculated using formula (7). :

[0079] (6)

[0080] (7)

[0081] The impedance of the new energy black-box model adopts the 2×2 admittance matrix form as follows:

[0082] Based on the positive and negative sequence impedance scan results, the admittance of the measured object is written in 2×2 matrix form according to formula (8):

[0083] (8)

[0084] In the formula: The positive-order admittance of the object under test; The negative-order coupling admittance of the object under test; The positive-order coupling admittance of the object under test; The negative-order admittance of the object being tested.

[0085] This enables the calculation of the impedance model of the new energy black box model.

[0086] It should be noted that: the ADPSS simulation model corresponding to the new energy black box model refers to the simulation model that includes both the simulated power grid module and the new energy model as a whole; the new energy black box model that only includes the simulated power grid module for subsequent stability analysis refers to the new energy model being disconnected, leaving only the simulated power grid module.

[0087] Based on this, power grid stability analysis can be performed using the impedance obtained from frequency sweeping. Before performing the power grid stability analysis, it should be noted that the corresponding computer storage medium and the ADPSS-based new energy model impedance frequency sweeping device can be obtained from the computer program corresponding to the aforementioned ADPSS-based new energy model impedance frequency sweeping method. Specifically,

[0088] This embodiment also provides a computer storage medium storing at least one instruction, which is loaded and executed by a processor to implement the impedance sweep frequency method for a new energy model based on ADPSS.

[0089] It should be understood that the instructions include computer program products, software, or computerized methods corresponding to any method described in this invention; the instructions can be used to program computer systems or other electronic devices. Computer storage media may include readable media on which instructions are stored, and may include, but are not limited to, magnetic storage media, optical storage media; magneto-optical storage media include read-only memory (ROM), random access memory (RAM), erasable programmable memory (e.g., EPROM and EEPROM), and flash memory layers, or other types of media suitable for storing electronic instructions.

[0090] This embodiment can also provide a new energy model impedance sweep frequency device based on ADPSS. The device includes a processor and a memory. It should be understood that this includes any device including a processor and a memory described in this invention. The device may also include other units and modules that perform display, interaction, processing, control and other functions through signals or instructions.

[0091] The memory stores at least one instruction, which is loaded and executed by the processor to implement the impedance sweep frequency method for a new energy model based on ADPSS.

[0092] Those skilled in the art will understand that at least one stored instruction constitutes a computer program product corresponding to a method or system. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0093] This application is described with reference to flowchart illustrations and / or block diagrams of methods, systems, and computer program products according to embodiments of this application, and can also be used with corresponding devices. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0094] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0095] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 6 The steps of the function specified in one or more boxes.

[0096] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0097] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

[0098] The following describes the power grid stability analysis based on the impedance obtained from frequency sweeping. The analysis method includes:

[0099] The grid impedance is swept using a frequency sweep and calculated. A stability criterion is then used to determine if there is a risk of resonance between the renewable energy source and the grid. The positive-sequence impedance sweep method used in this process is as follows:

[0100] The new energy black box model and the simulated power grid module were disconnected. A frequency of [frequency value missing] was injected into the new energy black box model, which only contains the simulated power grid module, through the harmonic signal generation module. The positive-sequence current disturbance is used to perform a Fourier transform on the extracted three-phase voltage and current data to extract the positive-sequence voltage response component. and positive sequence current disturbance component The positive-sequence admittance of the power grid is calculated using formula (9). :

[0101] (9)

[0102] when At that time, extract the positive sequence current response component. The positive-sequence coupling admittance of the power grid is calculated using formula (10). :

[0103] (10)

[0104] when At that time, extract the negative sequence current response component. The positive-sequence coupling admittance is calculated using formula (3). :

[0105] (11)

[0106] During the process of frequency sweeping and calculating the grid impedance, the negative sequence impedance scanning method is as follows:

[0107] Injecting frequencies into the ADPSS power grid model through disturbance sources Negative sequence current disturbance, when Extracting the positive sequence voltage response component Positive sequence current disturbance component and positive sequence current response components The negative-order admittance is calculated using formula (12). The negative-order coupling admittance is calculated using formula (13). :

[0108] (12)

[0109] (13)

[0110] when At that time, extract the negative sequence voltage response component. Extracting the negative sequence current disturbance component and positive sequence current response components The negative-order admittance is calculated using formula (14). The negative-order coupling admittance is calculated using formula (15). :

[0111] (14)

[0112] (15)

[0113] The grid admittance can be written in 2×2 matrix form:

[0114] (16)

[0115] The stability criterion used to determine whether the new energy black-box model has a resonance risk with the power grid is as follows:

[0116] The positive sequence impedance of the new energy black-box model considering grid interaction is calculated according to formulas (17) and (18). and negative sequence impedance :

[0117] (17)

[0118] (18)

[0119] According to the positive sequence admittance of the power grid Calculate the positive sequence impedance of the power grid And thus obtain Positive sequence impedance as a stability criterion for new energy black-box models positive sequence impedance ratio According to the negative sequence admittance of the power grid Calculate the negative sequence impedance of the power grid And thus obtain Negative sequence impedance, a stability criterion for new energy black-box models negative sequence impedance ratio Determine the positive sequence impedance ratio and negative sequence impedance Compare whether the Nyquist stability criterion is satisfied to calculate the stability margin of the new energy black-box model. Stability criteria such as Figure 1 As shown.

[0120] The purpose of this invention is to provide an impedance frequency sweep method for new energy black-box models based on ADPSS, which is used to accurately extract the external characteristic impedance model when the new energy black-box model is black-box packaged and its internal control parameters are unavailable. By injecting controllable harmonic disturbance signals into the ADPSS simulation model and recording the response data, the small-signal impedance of the simulation model at different frequencies can be obtained, providing a reliable means for stability analysis, resonance risk identification, and model verification of new energy grid-connected systems. This method is particularly suitable for measuring the impedance characteristics of new energy equipment such as wind power and photovoltaics in grid-connected scenarios.

[0121] It should also be noted that, for a power grid stability analysis method based on the impedance frequency sweep of a new energy model using ADPSS, a corresponding computer storage medium and a power grid stability analysis device based on the impedance frequency sweep of a new energy model using ADPSS can also be obtained based on the computer program corresponding to the analysis method. Specifically,

[0122] This embodiment also provides a computer storage medium storing at least one instruction, which is loaded and executed by a processor to implement the aforementioned method for power grid stability analysis based on impedance sweep frequency of a new energy model using ADPSS.

[0123] It should be understood that the instructions include computer program products, software, or computerized methods corresponding to any method described in this invention; the instructions can be used to program computer systems or other electronic devices. Computer storage media may include readable media on which instructions are stored, and may include, but are not limited to, magnetic storage media, optical storage media; magneto-optical storage media include read-only memory (ROM), random access memory (RAM), erasable programmable memory (e.g., EPROM and EEPROM), and flash memory layers, or other types of media suitable for storing electronic instructions.

[0124] This embodiment also provides a grid stability analysis device based on the impedance sweep frequency of a new energy model using ADPSS. The device includes a processor and a memory. It should be understood that this includes any device described in this invention that includes a processor and a memory. The device may also include other units or modules that perform display, interaction, processing, control, and other functions through signals or instructions.

[0125] The memory stores at least one instruction, which is loaded and executed by the processor to implement the aforementioned method for power grid stability analysis based on impedance frequency sweep of a new energy model using ADPSS.

[0126] Those skilled in the art will understand that at least one stored instruction constitutes a computer program product corresponding to a method or system. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0127] This application is described with reference to flowchart illustrations and / or block diagrams of methods, systems, and computer program products according to embodiments of this application, and can also be used with corresponding devices. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0128] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0129] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes ​ The steps of the function specified in one or more boxes.

[0130] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0131] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

[0132] The above examples of the present invention are merely illustrative of the computational model and process of the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is impossible to exhaustively list all possible implementations here. Any obvious variations or modifications derived from the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. An impedance frequency sweep method for new energy models based on ADPSS, characterized in that, include: S1. Establish a harmonic signal generation module using ADPSS software. The input of the harmonic signal generation module is used to record the three-phase voltage and current at the frequency sweep test point, and its output is used to generate a disturbance frequency signal that varies with time, simulating the injection of harmonic disturbance signals into the power grid. Set the harmonic phase sequence of the harmonic signal generation module to positive and negative, and perform subsequent processing once for each. S2. Connect the harmonic voltage reference signal generated by the harmonic signal generation module to the controlled voltage source of the simulated power grid module of the new energy black box model to be swept, perform simulation, and record and store the response signal during the frequency sweep operation. S3. Extract the sweep frequency data, including input and output data, and import it into software capable of numerical calculation and numerical analysis; S4. Calculate the impedance of the new energy black-box model, including the positive-sequence admittance. and positive-sequence coupling admittance and negative order admittance and negative order coupling admittance This enables the calculation of the impedance model for the black-box model of new energy.

2. The impedance frequency sweep method for a new energy model based on ADPSS according to claim 1, characterized in that, When setting up the harmonic signal generation module, the disturbance frequency is divided into multiple frequency ranges, and different frequency step sizes are set in different frequency ranges, thereby realizing the generation of wide-band, multi-resolution sweeping disturbance signals.

3. The impedance frequency sweep method for a new energy model based on ADPSS according to claim 1, characterized in that, The specific process of step S2 includes: The three-phase voltage signals at the impedance calculation point are connected to the input ports Ua, Ub, and Uc of the harmonic signal generation module, and the corresponding three-phase current signals are connected to the input ports Ia, Ib, and Ic. Before the simulation runs, the three-phase voltage and three-phase current response data under the action of the harmonic signal generation module are automatically stored in the working directory of the model and corresponding data files are generated. The input data file records the three-phase voltage and current data at the input of the harmonic signal generation module, and the output data file records the harmonic voltage command signal and disturbance frequency data output by the harmonic signal generation module.

4. The impedance frequency sweep method for a new energy model based on ADPSS according to any one of claims 1 to 3, characterized in that, In step S4, the impedance calculation of the new energy black box model is divided into positive sequence impedance measurement and negative sequence impedance measurement. The formula for calculating positive sequence impedance is as follows: Based on the harmonic phase sequence setting of the harmonic signal generation module to positive corresponding data, the harmonic signal generation module injects a frequency of [frequency value missing] into the ADPSS simulation model corresponding to the new energy black box model. The positive-sequence voltage disturbance component is extracted by performing a Fourier transform on the extracted three-phase voltage and current data. and positive sequence current response components And calculate the positive-sequence admittance. ; when At that time, extract the positive sequence current response component. According to its complex conjugate form and Calculate positive-sequence coupling admittance Or when At that time, extract the negative sequence current response component. and combined Calculate positive-sequence coupling admittance ; The formula for calculating negative sequence impedance is as follows: Based on the harmonic phase sequence setting of the harmonic signal generation module to the negative corresponding data, the frequency is injected into the ADPSS simulation model corresponding to the new energy black box model through the harmonic signal generation module. Negative sequence voltage disturbance; when At that time, extract the positive sequence voltage disturbance component. Positive sequence current response component and positive sequence current response components ,according to The complex conjugate form and Calculating the negative order admittance in the complex conjugate form and according to and Calculating the negative-order coupling admittance in the complex conjugate form ; Or, when At that time, the negative sequence voltage disturbance component is extracted. Extracting the negative sequence current response component and positive sequence current response components ,according to and Calculate negative-order admittance ,according to and Calculate negative-order coupling admittance .

5. A computer storage medium, characterized in that, The storage medium stores at least one instruction, which is loaded and executed by a processor to implement the impedance sweep frequency method for a new energy model based on ADPSS as described in any one of claims 1 to 4.

6. A new energy model impedance sweep frequency device based on ADPSS, characterized in that, The device includes a processor and a memory, the memory storing at least one instruction, which is loaded and executed by the processor to implement the impedance sweep frequency method for a new energy model based on ADPSS as described in any one of claims 1 to 4.

7. A grid stability analysis method based on impedance frequency sweep of a new energy model using ADPSS, characterized in that, The impedance of a new energy black-box model, including positive-sequence admittance, is obtained by an impedance sweep frequency method based on ADPSS according to any one of claims 1 to 4. and positive-sequence coupling admittance and negative order admittance and negative order coupling admittance ; Power grid stability analysis is performed based on impedance obtained from frequency sweep, including: The grid impedance is swept by frequency and calculated. The stability criterion is used to determine whether there is a risk of resonance between the new energy source and the grid. During the process of frequency sweeping and calculating the grid impedance, the positive sequence impedance scanning method is as follows: The new energy black box model and the simulated power grid module are disconnected. A frequency of [frequency value missing] is injected into the new energy black box model, which only contains the simulated power grid module, through the harmonic signal generation module. The positive-sequence current disturbance is used to perform a Fourier transform on the extracted three-phase voltage and current data to extract the positive-sequence voltage response component. and positive sequence current disturbance component And calculate the positive-sequence admittance of the power grid. ; when At that time, extract the positive sequence current response component. According to its complex conjugate form and Calculate the positive-sequence coupling admittance of the power grid Or, when At that time, extract the negative sequence current response component. , combined Calculate positive-sequence coupling admittance ; During the process of frequency sweeping and calculating the grid impedance, the negative sequence impedance scanning method is as follows: Injecting frequencies into the ADPSS power grid model through disturbance sources Negative sequence current disturbance; when Extracting the positive sequence voltage response component Positive sequence current disturbance component and positive sequence current response components ,according to The complex conjugate form and Calculating negative order admittance using the conjugate form of the number ,according to and Calculate the negative-order coupling admittance using the conjugate form of the numbers. Or, when At that time, extract the negative sequence voltage response component. Extracting the negative sequence current disturbance component and positive sequence current response components ,according to and Calculate negative-order admittance ,according to and Calculate negative-order coupling admittance ; The stability criterion is used to determine whether there is a resonance risk between the new energy black-box model and the power grid. The stability criterion is as follows: Positive sequence impedance of a new energy black-box model considering grid interaction and negative sequence impedance According to the positive sequence admittance of the power grid Calculate the positive sequence impedance of the power grid And thus obtain Positive sequence impedance as a stability criterion for new energy black-box models positive sequence impedance ratio According to the negative sequence admittance of the power grid Calculate the negative sequence impedance of the power grid And thus obtain Negative sequence impedance, a stability criterion for new energy black-box models negative sequence impedance ratio Determine the positive sequence impedance ratio and negative sequence impedance Compare whether the Nyquist stability criterion is satisfied to calculate the stability margin of the new energy black-box model. This enables power grid stability analysis.

8. The grid stability analysis method based on impedance sweep frequency of a new energy model according to claim 7, characterized in that, Positive sequence impedance of a new energy black-box model considering grid interaction and negative sequence impedance as follows: (17) (18)。 9. A computer storage medium, characterized in that, The storage medium stores at least one instruction, which is loaded and executed by a processor to implement the grid stability analysis method based on impedance sweep frequency of a new energy model according to any one of claims 7 to 8.

10. A power grid stability analysis device based on impedance sweep frequency analysis of a new energy model using ADPSS, characterized in that, The device includes a processor and a memory, the memory storing at least one instruction, which is loaded and executed by the processor to implement the grid stability analysis method based on impedance sweep frequency of a new energy model according to any one of claims 7 to 8.

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