A simulation analysis method and device based on an RTDS large power grid equivalent model

Abstract

The application discloses a simulation analysis method and device based on an RTDS large power grid equivalent model, and is applied to RTDS and a DC hybrid large power grid, and the method comprises the following steps: S1, a first bus with a new energy unit is randomly acquired, and the first bus is put into a pre-set task queue; S2, based on the first bus and the task queue, an equivalent modeling is performed on the new energy unit in combination with a pre-set voltage threshold value, so that a power grid equivalent model is obtained; S3, it is judged whether all nodes in the task queue have been traversed; if not, the step S2 is returned to be executed; and S4, a simulation analysis instruction is received, simulation analysis is performed by using the equivalent model, and a simulation analysis result is obtained. Based on the RTDS platform, the establishment and simulation analysis of the large power grid equivalent model are realized, and under the condition of high proportion of new energy penetration at the present stage, a large amount of simulation resources is saved.

Description

Technical Field

[0001] This invention relates to the field of simulation analysis technology, and in particular to a simulation analysis method and apparatus based on the RTDS large power grid equivalent model. Background Technology

[0002] With the rapid development of large-scale AC / DC hybrid power grids and the booming penetration of high-proportion renewable energy sources, full electromagnetic transient modeling and simulation analysis of large-scale AC / DC hybrid power grids has become an inevitable requirement for power grid development. However, the huge computational load of electromagnetic transient simulation leads to reduced simulation efficiency, which in turn restricts its application to actual large-scale power grids.

[0003] While Real-Time Digital Simulators (RTDS) fully utilize massively parallel computing technology and are currently recognized as highly efficient electromagnetic transient simulation devices, their computing power is highly dependent on hardware configuration. To achieve full electromagnetic transient simulation of large-scale AC / DC hybrid power grids, significant investment in hardware is required. Furthermore, in practical applications, large power grid models with a high proportion of renewable energy penetration involve substantial computational demands on renewable energy models, necessitating a reduction in system scale while maintaining simulation accuracy.

[0004] In summary, given the current high penetration rate of new energy sources, there is still no efficient equivalent method for RTDS platforms under AC / DC hybrid power grids. Summary of the Invention

[0005] This invention provides a simulation analysis method and apparatus based on the RTDS equivalent model of a large power grid. Based on the RTDS platform, it realizes the establishment and simulation analysis of the equivalent model of a large power grid, saving a lot of simulation resources under the current situation of high penetration of new energy.

[0006] In a first aspect, the present invention provides a simulation analysis method based on an equivalent model of a large power grid using RTDS, applicable to RTDS and DC hybrid power grids, comprising:

[0007] S1, randomly select the first bus with the new energy unit and put the first bus into a pre-set task queue;

[0008] S2, based on the first bus and the task queue, and combined with the preset voltage threshold, perform equivalent modeling on the new energy generating unit to obtain the power grid equivalent model;

[0009] S3, determine whether all nodes in the task queue have been traversed; if not, return to step S2.

[0010] S4, Receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results.

[0011] Optionally, step 2 includes:

[0012] S21, Select the first node in the task queue and determine the transformer connected to the first node;

[0013] S22, perform a bus search for the first busbar from the high-voltage side of the transformer, combine it with a pre-set voltage threshold, perform equivalent modeling of the new energy generating unit, obtain the power grid equivalent model, and remove the first node.

[0014] Optionally, step S22 includes:

[0015] S221, perform a bus search on the high-voltage side of the transformer to determine if there is a second bus with a voltage level higher than the voltage threshold; if yes, proceed to step S222; if no, proceed to step S223.

[0016] S222, the bus search of the first bus is ended, the first bus is defined as equivalent to the second bus, and the equivalent model of the new energy unit is performed based on the second bus to obtain the power grid equivalent model;

[0017] S223, add all buses connected to the first bus to the task queue.

[0018] Optionally, step S222 includes:

[0019] All new energy generating units that are equivalent to the second busbar are statistically analyzed, and the active and reactive power of the new energy generating units are statistically summed according to their types to obtain the initial power grid equivalent model.

[0020] The multiplication coefficients of the initial power grid equivalent model are modified to obtain the power grid equivalent model.

[0021] Secondly, the present invention also provides a simulation analysis device based on an RTDS large power grid equivalent model, applicable to RTDS and DC hybrid large power grids, comprising:

[0022] The acquisition module is used to randomly acquire the first bus with the new energy unit and put the first bus into a pre-set task queue;

[0023] The power grid equivalent model determination module is used to perform equivalent modeling of the new energy generating unit based on the first bus and the task queue, combined with a pre-set voltage threshold, to obtain the power grid equivalent model.

[0024] The judgment module is used to determine whether all nodes in the task queue have been traversed; if not, the power grid equivalent model determination module is executed.

[0025] The simulation analysis module is used to receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results.

[0026] Optionally, the power grid equivalent model determination module includes:

[0027] The node determination submodule is used to select the first node in the task queue and determine the transformer connected to the first node;

[0028] The elimination submodule is used to perform bus search on the first bus from the high-voltage side of the transformer. Combined with a pre-set voltage threshold, the equivalent model of the new energy unit is performed to obtain the power grid equivalent model, and the first node is eliminated.

[0029] Optionally, the rejection submodule includes:

[0030] The judgment unit is used to perform the bus search in the high-voltage side direction of the transformer to determine whether there is a second bus with a voltage level higher than the voltage threshold; if yes, the power grid equivalent model unit is executed; if no, the task queue addition unit is executed.

[0031] The power grid equivalent model is used to end the bus search of the first bus, define the first bus as equivalent to the second bus, and perform equivalent modeling of the generating unit with new energy based on the second bus to obtain the power grid equivalent model.

[0032] The task queue addition unit is used to add all buses connected to the first bus to the task queue.

[0033] Optionally, the power grid equivalent model includes:

[0034] The statistical subunit is used to statistically analyze all new energy generating units that are equivalent to the second bus, and to statistically sum the active and reactive power of the new energy generating units according to their types to obtain the initial power grid equivalent model.

[0035] The correction subunit is used to modify the multiplication coefficients of the initial power grid equivalent model to obtain the power grid equivalent model.

[0036] A third aspect of this application provides an electronic device, the device including a processor and a memory;

[0037] The memory is used to store program code and transmit the program code to the processor;

[0038] The processor is used to execute the simulation analysis method based on the RTDS large power grid equivalent model as described in the first aspect, according to the instructions in the program code.

[0039] The fourth aspect of this application provides a computer-readable storage medium for storing program code for executing the simulation analysis method based on the RTDS large power grid equivalent model described in the first aspect.

[0040] As can be seen from the above technical solutions, the present invention has the following advantages:

[0041] This invention discloses a simulation analysis method and apparatus based on an RTDS-based equivalent model of a large power grid, applicable to RTDS and DC-DC hybrid power grids. The method includes: S1, randomly selecting a first bus with renewable energy units and placing it in a pre-set task queue; S2, based on the first bus and the task queue, and combined with a pre-set voltage threshold, performing equivalent modeling on the renewable energy units to obtain a power grid equivalent model; S3, determining whether all nodes in the task queue have been traversed; if not, returning to step S2; S4, receiving a simulation analysis command, performing simulation analysis using the equivalent model, and obtaining simulation analysis results. Based on the RTDS platform, this method enables the establishment and simulation analysis of a large power grid equivalent model, saving significant simulation resources in the current context of high renewable energy penetration. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating the steps of a simulation analysis method based on an RTDS large power grid equivalent model according to the present invention. Detailed Implementation

[0044] This invention provides a simulation analysis method and apparatus based on the RTDS equivalent model of a large power grid. Based on the RTDS platform, it realizes the establishment and simulation analysis of the equivalent model of a large power grid, saving a lot of simulation resources under the current situation of high proportion of new energy penetration.

[0045] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0046] The study of the safety and stability of large-scale AC / DC hybrid power grids has become a hot topic of concern in the domestic academic and engineering communities. Power system digital simulation is an effective tool for studying the operating characteristics of large-scale AC / DC hybrid power grids, and the accuracy of digital simulation will directly affect the reliability of the analysis results.

[0047] Electromechanical transient simulation analysis examines the synchronous stability between generators at the overall system level. Its core is the study of the swaying process between generator rotors caused by energy transfer. However, energy transfer in power networks is primarily determined by the positive-sequence fundamental frequency component. Therefore, electromechanical transient simulations based on the positive-sequence fundamental phasor model cannot describe the interaction characteristics between AC and DC systems at non-fundamental frequencies. Furthermore, electromechanical transient simulation software generally uses a DC quasi-steady-state model to simulate the dynamic response process of DC systems, which suffers from problems such as inaccurate judgment of commutation failure under asymmetrical faults and insufficient accuracy in fault recovery processes.

[0048] Electromagnetic transient simulation primarily studies the changes in instantaneous voltage and current values ​​over short periods. Based on a three-phase instantaneous value model, it uses differential equations to describe the system. The variables in the system are no longer phasors but three-phase instantaneous values. The simulation model considers the nonlinear dynamic characteristics of components and the distributed parameter characteristics of lines, enabling accurate simulation of the switching processes of power electronic equipment such as high-voltage direct current (HVDC) systems and flexible AC transmission systems (FACTS), and realistically reflecting the dynamic characteristics of power electronic equipment. However, the computational power of RTDS is highly dependent on hardware configuration. To achieve full electromagnetic transient simulation of large-scale AC / DC hybrid power grids, significant investment in hardware is required. Furthermore, in practical applications, large power grid models with a high proportion of renewable energy penetration involve large computational demands on renewable energy models, necessitating a reduction in system scale while maintaining simulation accuracy.

[0049] To address the aforementioned problems, this invention discloses a power flow control method for distribution networks across voltage levels, applicable to RTDS and DC-DC hybrid power grids, comprising:

[0050] S1, randomly select the first bus with the new energy unit and put the first bus into a pre-set task queue;

[0051] S2, based on the first bus and the task queue, and combined with the preset voltage threshold, perform equivalent modeling on the new energy generating unit to obtain the power grid equivalent model;

[0052] Specifically, step 2 includes:

[0053] S21, Select the first node in the task queue and determine the transformer connected to the first node;

[0054] S22, perform a bus search for the first busbar from the high-voltage side of the transformer, combine it with a pre-set voltage threshold, perform equivalent modeling of the new energy generating unit, obtain the power grid equivalent model, and remove the first node.

[0055] In an optional embodiment, step S22 includes:

[0056] S221, perform a bus search on the high-voltage side of the transformer to determine if there is a second bus with a voltage level higher than the voltage threshold; if yes, proceed to step S222; if no, proceed to step S223.

[0057] S222, the bus search of the first bus is ended, the first bus is defined as equivalent to the second bus, and the equivalent model of the new energy unit is performed based on the second bus to obtain the power grid equivalent model;

[0058] S223, add all buses connected to the first bus to the task queue.

[0059] S3, determine whether all nodes in the task queue have been traversed; if not, return to step S2.

[0060] S4, Receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results.

[0061] In this embodiment of the invention, step S1 involves randomly selecting a first busbar with renewable energy units and placing it into a pre-defined task queue; step S2 involves performing equivalent modeling on the renewable energy units based on the first busbar and the task queue, combined with a pre-defined voltage threshold, to obtain an equivalent power grid model; step S3 involves determining whether all nodes in the task queue have been traversed; if not, the process returns to step S2; and step S4 involves receiving a simulation analysis command, performing simulation analysis using the equivalent model, and obtaining the simulation analysis results. Based on the RTDS platform, this invention enables the establishment and simulation analysis of a large power grid equivalent model, saving significant simulation resources in the current context of high renewable energy penetration.

[0062] Please see Figure 1 , Figure 1This is a flowchart illustrating the steps of a simulation analysis method based on an equivalent model of a large power grid using RTDS, according to an embodiment of the present invention; applied to RTDS and DC hybrid power grids, the method includes:

[0063] S201, randomly select the first bus with the new energy unit and put the first bus into a pre-set task queue;

[0064] It should be noted that RTDS stands for Real Time Digital Simulator, a simulation device specifically designed for studying electromagnetic transient phenomena in power systems.

[0065] In the specific implementation, the first bus, BUS A, which is randomly selected and equipped with new energy generators, is placed into a pre-set task queue.

[0066] S202, Select the first node in the task queue and determine the transformer connected to the first node;

[0067] S203, perform a bus search on the high-voltage side of the transformer to determine if there is a second bus with a voltage level higher than the voltage threshold; if yes, proceed to step S204; if no, proceed to step S206.

[0068] S204, count all new energy generating units that are equivalent to the second bus, and according to the type of the new energy generating units, sum the active and reactive power of the new energy generating units to obtain the initial power grid equivalent model;

[0069] S205, Modify the multiplication coefficients of the initial power grid equivalent model to obtain the power grid equivalent model;

[0070] S206, add all the buses connected to the first bus to the task queue;

[0071] In this embodiment of the invention, the first node is retrieved from the task queue, and a bus search is performed on the high-voltage side of the grid through the transformer connected to it. If there is a bus B with a voltage level higher than the voltage threshold (i.e., 220kV), i.e., the second bus, then all new energy generating units equivalent to the second bus are counted, and the active and reactive power of the new energy generating units are statistically summed according to their types to obtain an initial grid equivalent model. Then, the multiplication factor of the new energy generating unit model is modified to complete the equivalence and obtain the grid equivalent model. If not, all bus lines connected to the first bus through the line are added to the queue.

[0072] S207, determine whether all nodes in the task queue have been traversed; if not, return to step S202.

[0073] S208, Receive simulation analysis command, perform simulation analysis using the equivalent model, and obtain simulation analysis results.

[0074] In this embodiment of the invention, when a simulation analysis instruction is received from the operation and maintenance personnel, the model obtained in step S205 is used to perform simulation analysis, thereby obtaining the simulation analysis result.

[0075] Most renewable energy units connect to the grid at voltage levels below 220kV. However, in RTDS electromagnetic transient simulations, large power grid models typically only use models with grid structures above 220kV because there are too many nodes below 220kV, resulting in excessive computational resource requirements. Therefore, the high proportion of renewable energy grid connection exacerbates the conflict between resources and simulation scale. Thus, it is necessary to equate the buses containing renewable energy units along the high-voltage direction. The grid topology can be considered a graph structure; therefore, each bus carrying renewable energy units can be regarded as a unit node. Buses found from these unit nodes through transformers towards the high-voltage side can all be considered as the same node on the graph, and the lines connecting the various buses can be considered as connections on the graph. This invention provides a simulation analysis method and apparatus based on an RTDS-based equivalent model of a large power grid, applicable to RTDS and DC-DC hybrid power grids. The method includes: S1, randomly selecting a first busbar carrying renewable energy units and placing it in a pre-set task queue; S2, based on the first busbar and the task queue, and combined with a pre-set voltage threshold, performing equivalent modeling on the renewable energy units to obtain a power grid equivalent model; S3, determining whether all nodes in the task queue have been traversed; if not, returning to step S2; S4, receiving a simulation analysis instruction, performing simulation analysis using the equivalent model, and obtaining simulation analysis results. Based on the RTDS platform, a breadth-first search algorithm is used to find the nearest high-voltage busbar of 220kV or higher to each busbar carrying renewable energy units to be equivalently modeled, thereby completing the establishment and simulation analysis of the equivalent model of the large power grid. This saves significant simulation resources in the current context of high renewable energy penetration.

[0076] This invention also provides a simulation analysis device based on the RTDS large power grid equivalent model, applicable to RTDS and DC hybrid large power grids, including:

[0077] The acquisition module 301 is used to randomly acquire the first bus with the new energy unit and put the first bus into a pre-set task queue;

[0078] The power grid equivalent model determination module 302 is used to perform equivalent modeling on the new energy generating unit based on the first bus and the task queue, combined with a pre-set voltage threshold, to obtain the power grid equivalent model.

[0079] The judgment module 303 is used to determine whether all nodes in the task queue have been traversed; if not, the power grid equivalent model determination module is executed.

[0080] The simulation analysis module 304 is used to receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results.

[0081] In an optional embodiment, the power grid equivalent model determination module 302 includes:

[0082] The node determination submodule is used to select the first node in the task queue and determine the transformer connected to the first node;

[0083] The elimination submodule is used to perform bus search on the first bus from the high-voltage side of the transformer. Combined with a pre-set voltage threshold, the equivalent model of the new energy unit is performed to obtain the power grid equivalent model, and the first node is eliminated.

[0084] In an optional embodiment, the rejection submodule includes:

[0085] The judgment unit is used to perform the bus search in the high-voltage side direction of the transformer to determine whether there is a second bus with a voltage level higher than the voltage threshold; if yes, the power grid equivalent model unit is executed; if no, the task queue addition unit is executed.

[0086] The power grid equivalent model is used to end the bus search of the first bus, define the first bus as equivalent to the second bus, and perform equivalent modeling of the generating unit with new energy based on the second bus to obtain the power grid equivalent model.

[0087] The task queue addition unit is used to add all buses connected to the first bus to the task queue.

[0088] In one optional embodiment, the power grid equivalent model includes:

[0089] The statistical subunit is used to statistically analyze all new energy generating units that are equivalent to the second bus, and to statistically sum the active and reactive power of the new energy generating units according to their types to obtain the initial power grid equivalent model.

[0090] The correction subunit is used to modify the multiplication coefficients of the initial power grid equivalent model to obtain the power grid equivalent model.

[0091] This application also provides an electronic device, which includes a processor and a memory;

[0092] The memory is used to store program code and transfer the program code to the processor;

[0093] The processor is used to execute the simulation analysis method based on the RTDS large power grid equivalent model in the above method embodiment according to the instructions in the program code.

[0094] This application also provides a computer-readable storage medium for storing program code for executing the simulation analysis method based on the RTDS large power grid equivalent model in the above method embodiments.

[0095] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0096] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0097] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0098] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0099] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A simulation analysis method based on an equivalent model of a large power grid using RTDS, applied to RTDS and DC hybrid power grids, characterized in that... Includes the following steps: S1, randomly select the first bus with the new energy unit and put the first bus into a pre-set task queue; S2, based on the first bus and the task queue, and combined with the preset voltage threshold, perform equivalent modeling on the new energy generating unit to obtain the power grid equivalent model; S3, determine whether all nodes in the task queue have been traversed; if not, return to step S2. S4, Receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results; Step S2 includes steps S21 to S22: S21, Select the first node in the task queue and determine the transformer connected to the first node; S22, perform a bus search for the first busbar from the high-voltage side of the transformer, combine it with a pre-set voltage threshold, perform equivalent modeling of the new energy generating unit, obtain the power grid equivalent model, and remove the first node; Step S22 includes steps S221 to S223: S221, Search for the busbar from the high-voltage side of the transformer to determine whether there is a second busbar with a voltage level higher than the voltage threshold; if yes, proceed to step S222; if no, proceed to step S223. S222, the bus search of the first bus is ended, the first bus is defined as equivalent to the second bus, and the equivalent model of the new energy unit is performed based on the second bus to obtain the power grid equivalent model; S223, add all the buses connected to the first bus to the task queue; Step S222 includes: All new energy generating units that are equivalent to the second busbar are statistically analyzed, and the active and reactive power of the new energy generating units are statistically summed according to their types to obtain the initial power grid equivalent model. The multiplication coefficients of the initial power grid equivalent model are modified to obtain the power grid equivalent model.

2. A simulation analysis device based on an RTDS large power grid equivalent model, applied to RTDS and DC hybrid power grids, characterized in that, include: The acquisition module is used to randomly acquire the first bus with the new energy unit and put the first bus into a pre-set task queue; The power grid equivalent model determination module is used to perform equivalent modeling of the new energy generating unit based on the first bus and the task queue, combined with a pre-set voltage threshold, to obtain the power grid equivalent model. The judgment module is used to determine whether all nodes in the task queue have been traversed; if not, the power grid equivalent model determination module is executed. The simulation analysis module is used to receive simulation analysis instructions, perform simulation analysis using the equivalent model, and obtain simulation analysis results. The power grid equivalent model determination module includes: The node determination submodule is used to select the first node in the task queue and determine the transformer connected to the first node; The elimination submodule is used to perform bus search of the first bus from the high-voltage side of the transformer. Combined with a pre-set voltage threshold, the equivalent model of the new energy unit is performed to obtain the power grid equivalent model, and the first node is eliminated. The elimination submodule includes: The judgment unit is used to search for the bus from the high-voltage side of the transformer and determine whether there is a second bus with a voltage level higher than the voltage threshold; if yes, the power grid equivalent model unit is executed; if no, the task queue addition unit is executed. The power grid equivalent model is used to end the bus search of the first bus, define the first bus as equivalent to the second bus, and perform equivalent modeling of the generating unit with new energy based on the second bus to obtain the power grid equivalent model. The task queue addition unit is used to add all the buses connected to the first bus to the task queue; The power grid equivalent model includes: The statistical subunit is used to statistically analyze all new energy generating units that are equivalent to the second bus, and to statistically sum the active and reactive power of the new energy generating units according to their types to obtain the initial power grid equivalent model. The correction subunit is used to modify the multiplication coefficients of the initial power grid equivalent model to obtain the power grid equivalent model.

3. An electronic device, characterized in that, It includes a processor and a memory, the memory storing computer-readable instructions that, when executed by the processor, perform the method as described in claim 1.

4. A storage medium having a computer program stored thereon, characterized in that, The computer program, when executed by this processor, performs the method as described in claim 1.

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