A new energy base aggregation equivalent modeling method containing multiple control strategies

Abstract

This invention discloses a method for aggregate equivalent modeling of new energy bases with multiple control strategies, comprising: constructing an equivalent model of the relationship between the station-end voltage of a new energy power station and the bus voltage of the new energy base; constructing a positive-sequence network equivalent model and a negative-sequence network equivalent model of the new energy power station; performing aggregate equivalent modeling of the new energy base based on the relationship equivalent model and the positive-sequence network equivalent model to obtain a positive-sequence network aggregate equivalent model; performing series-parallel aggregate equivalent calculation based on the topology of the new energy base and the negative-sequence network equivalent model to obtain a negative-sequence network aggregate equivalent model; and constructing an aggregate equivalent model of the new energy base based on the positive-sequence network aggregate equivalent model and the negative-sequence network aggregate equivalent model, wherein the aggregate equivalent model of the new energy base is used for short-circuit calculation of the power system containing the new energy base.

Description

Technical Field

[0001] This invention relates to the field of relay protection setting calculation technology, and more specifically, to a method for aggregated equivalent modeling of new energy bases containing multiple control strategies. Background Technology

[0002] Relay protection, as the first line of defense in a power system, relies on setting calculations to provide the basis for setting values, thereby achieving efficient coordination between protection levels and ensuring rapid fault isolation and safe and stable system operation. Compared with conventional power sources, renewable energy sources exhibit strong controllability during fault processes. Therefore, voltage-controlled current sources and other equivalent renewable energy sources have been gradually adopted in the main grid protection setting calculation software, and short-circuit calculations are performed using iterative methods. During this process, the iterative convergence of short-circuit calculations decreases as the number of renewable energy nodes increases. Therefore, it is necessary to aggregate and equalize renewable energy sources to reduce the number of renewable energy nodes in power systems with large-scale renewable energy access during short-circuit calculations. Currently, renewable energy equivalent modeling in short-circuit calculations can only achieve station-level aggregation of renewable energy sources with the same type and control strategy, which is far from sufficient. It is necessary to be able to aggregate large renewable energy bases containing different renewable energy types and control strategies. This will greatly improve the iterative convergence of short-circuit calculations, making rapid and accurate setting calculations possible for power systems with large-scale renewable energy sources. However, the fault response characteristics of various wind turbine units and photovoltaic power generation units are different. Due to different spatial locations, different fault characteristics, and access topologies, it is difficult to calculate and aggregate equivalent values ​​for setting. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for aggregated equivalent modeling of new energy bases that incorporates multiple control strategies.

[0004] According to one aspect of the present invention, a method for aggregated equivalent modeling of new energy bases containing multiple control strategies is provided, comprising:

[0005] Construct an equivalent model of the relationship between the voltage at the station end of a new energy power plant and the voltage at the busbar of the new energy base, which includes multiple control strategies;

[0006] Construct positive-order and negative-order network equivalent models for new energy power plants;

[0007] Aggregate equivalence of new energy bases is performed based on relational equivalence model and orthogonal network equivalence model to obtain orthogonal network aggregate equivalence model;

[0008] Based on the topological relationship of the new energy base and the negative order network equivalent model, serial and parallel aggregation equivalent calculations are performed to obtain the negative order network aggregation equivalent model;

[0009] Based on the positive-order network aggregation equivalent model and the negative-order network aggregation equivalent model, a new energy base aggregation equivalent model is constructed, which is used to perform short-circuit calculations on power systems containing new energy bases.

[0010] Optionally, the expression for the relational equivalence model is:

[0011]

[0012] In the formula, and These are the positive and negative sequence voltage phasors of the new energy base's bus hub, respectively. and Let be the positive and negative sequence voltage phasors at the i-th renewable energy power station terminal; and Let be the positive and negative sequence current phasors output by the i-th renewable energy power station, with the positive direction defined as from the power station to the base busbar. and These are the positive and negative sequence impedances of the transmission line from the i-th renewable energy power station, respectively. and These are the positive and negative sequence impedances of the step-up transformer at the i-th renewable energy power station, respectively.

[0013] Optionally, the expression for the orthogonal network equivalence model is:

[0014]

[0015] In the formula, and δ i These are the station terminal voltage phasors. The amplitude and phase, and θ i Output current phasors of each station The amplitude and phase, and They are respectively The q-axis and d-axis components in the figure.

[0016] Optionally, the expression for the negative order network equivalent model is:

[0017] or

[0018] In the formula, The impedance K represents the equivalent of the negative sequence control characteristic of the station. - The slope is the equal value slope after approximating the voltage-current relationship in the negative sequence control characteristic as a linear relationship.

[0019] Optionally, the aggregation equivalence of new energy bases is performed based on the relational equivalence model and the orthogonal order network equivalence model to obtain the orthogonal order network aggregation equivalence model, including:

[0020] Step 1: Set the voltage of the new energy base's collecting bus. The amplitude is set, and the voltage phase is set to 0°, then step 2 is executed;

[0021] Step 2: Initialize the station terminal voltage of each station as follows The voltage amplitude is related to the voltage of the busbar of the new energy base. Equal, initialize the output current of each station as follows The amplitude is the rated current of each new energy power station, and then step 3 is executed;

[0022] Step 3: Iterative calculation. Based on the expression of the relational equivalent model, the station terminal voltage in the t-th iteration can be calculated. Furthermore, the station terminal voltage can be calculated based on the expression of the positive sequence network equivalent model. Corresponding station output current Then proceed to step 4;

[0023] Step 4: Determine convergence. If the station terminal voltages in the t-th iteration and the station terminal voltages in the (t-1)-th iteration satisfy the preset convergence criterion, then convergence is determined and step 5 is executed; otherwise, return to step 3.

[0024] Step 5: Calculate the overall output current of the new energy base based on the output current of each station, and then proceed to Step 6:

[0025] Step 6: Set the bus voltage for different new energy bases Amplitude, repeat step 1, and finally obtain and θ Base The corresponding numerical sequence of relations is used to characterize the orthogonal network aggregation equivalent model.

[0026] Optionally, the convergence criterion can be expressed as:

[0027]

[0028] In the formula, ε i This represents the difference between the station-end voltage of the i-th power station in the two iterations.

[0029] Optionally, the formula for calculating the overall output current is:

[0030]

[0031] In the formula, and θBase These are the phasor, amplitude, and phase angle of the overall output current of the new energy base.

[0032] According to another aspect of the present invention, a new energy base aggregation equivalent modeling device with multiple control strategies is provided, comprising:

[0033] The first construction module is used to construct an equivalent model of the relationship between the voltage at the station end of the new energy power plant and the voltage at the bus of the new energy base, which includes multiple control strategies.

[0034] The second construction module is used to construct the positive-order network equivalent model and the negative-order network equivalent model of the new energy power station;

[0035] The first aggregation module is used to perform aggregation equivalence of new energy bases based on relational equivalence models and orthogonal network equivalence models, and to obtain orthogonal network aggregation equivalence models.

[0036] The second aggregation module is used to perform series and parallel aggregation equivalence calculations based on the topological relationship of the new energy base and the negative order network equivalence model, and to obtain the negative order network aggregation equivalence model.

[0037] The third construction module is used to construct the new energy base aggregation equivalent model based on the positive order network aggregation equivalent model and the negative order network aggregation equivalent model. The new energy base aggregation equivalent model is used to perform short-circuit calculations on the power system containing the new energy base.

[0038] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing a computer program for performing the methods described in any of the above aspects of the present invention.

[0039] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor being configured to read the executable instructions from the memory and execute the instructions to implement the method described in any of the preceding aspects of the present invention.

[0040] Therefore, based on the voltage and current output characteristics of new energy power plants with different control strategies, this invention proposes an aggregated equivalent modeling method for new energy bases with multiple control strategies. This method reduces the number of nonlinear components in short-circuit calculations of power systems with large-scale new energy, improves the iterative convergence of short-circuit calculations, and thus enhances the accuracy of the setting calculation results for new power systems. Attached Figure Description

[0041] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0042] Figure 1This is a flowchart illustrating an exemplary embodiment of the present invention for a method of aggregated equivalent modeling of new energy bases containing multiple control strategies;

[0043] Figure 2 This is a schematic diagram of a typical new energy base consisting of multiple new energy power stations, provided by an exemplary embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the equivalent modeling process for the aggregation of port voltage and output current of a new energy base provided in an exemplary embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram illustrating an example of the aggregation of port voltage and output current at a new energy base provided in an exemplary embodiment of the present invention;

[0046] Figure 5 This is a schematic diagram of the structure of a new energy base aggregation equivalent modeling device with multiple control strategies provided in an exemplary embodiment of the present invention;

[0047] Figure 6 This is the structure of an electronic device provided in an exemplary embodiment of the present invention. Detailed Implementation

[0048] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein.

[0049] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0050] Those skilled in the art will understand that the terms "first," "second," etc., in the embodiments of the present invention are only used to distinguish different steps, devices, or modules, and do not represent any specific technical meaning, nor do they indicate a necessary logical order between them.

[0051] It should also be understood that in the embodiments of the present invention, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0052] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more unless explicitly defined or given contrary instructions in the context.

[0053] Furthermore, the term "and / or" in this invention is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this invention generally indicates that the preceding and following related objects have an "or" relationship.

[0054] It should also be understood that the description of the various embodiments in this invention emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0055] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0056] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0057] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0058] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0059] The embodiments of this invention can be applied to electronic devices such as terminal devices, computer systems, and servers, and can operate together with a wide range of other general-purpose or special-purpose computing system environments or configurations. Well-known examples of terminal devices, computing systems, environments, and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, and servers include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputer systems, mainframe computer systems, and distributed cloud computing environments including any of the above systems, etc.

[0060] Electronic devices such as terminal devices, computer systems, and servers can be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in distributed cloud computing environments, where tasks are executed by remote processing devices linked through communication networks. In distributed cloud computing environments, program modules can reside on local or remote computing system storage media, including storage devices.

[0061] Exemplary methods

[0062] Figure 1 This is a flowchart illustrating an exemplary embodiment of the present invention regarding a method for aggregated equivalent modeling of new energy bases incorporating multiple control strategies. This embodiment can be applied to electronic devices, such as… Figure 1 As shown, the aggregated equivalent modeling method 100 for new energy bases with multiple control strategies includes the following steps:

[0063] Step 101: Construct an equivalent model of the relationship between the voltage at the station end of the new energy power plant and the voltage at the busbar of the new energy base, which includes multiple control strategies.

[0064] Step 102: Construct the positive-order network equivalent model and the negative-order network equivalent model of the new energy power station;

[0065] Step 103: Perform aggregate equivalence of new energy bases based on relational equivalence model and orthogonal network equivalence model to obtain orthogonal network aggregate equivalence model;

[0066] Step 104: Perform serial-parallel aggregation equivalence calculations based on the topological relationship of the new energy base and the negative-order network equivalence model to obtain the negative-order network aggregation equivalence model;

[0067] Step 105: Based on the positive-order network aggregation equivalent model and the negative-order network aggregation equivalent model, construct the new energy base aggregation equivalent model, whereby the new energy base aggregation equivalent model is used to perform short-circuit calculations on power systems containing new energy bases.

[0068] Specifically, such as Figure 2 The diagram shows a typical topology of a renewable energy base consisting of multiple renewable energy plants connected to different transmission lines. The types of plants, total capacity, and control characteristics vary, and they generally converge at a substation busbar of the same voltage level via different lines. Therefore, the traditional single-unit multiplication approach cannot be used to equate their output characteristics. This paper proposes an aggregated equivalent modeling method for renewable energy bases with multiple control strategies, suitable for power system short-circuit calculations. The steps are as follows:

[0069] 1) Assuming the aggregated equivalent modeling scope of the new energy base is the busbar of the power station's outgoing lines and the downstream new energy systems connected to it, and ignoring the ground capacitance current of the outgoing lines, the following expression holds:

[0070]

[0071] In the formula, and These are the positive and negative sequence voltage phasors of the new energy base's bus hub, respectively. and Let be the positive and negative sequence voltage phasors at the i-th renewable energy power station terminal; and Let be the positive and negative sequence current phasors output by the i-th renewable energy power station, with the positive direction defined as from the power station to the base busbar. and These are the positive and negative sequence impedances of the transmission line from the i-th renewable energy power station, respectively. and These are the positive and negative sequence impedances of the step-up transformer at the i-th renewable energy power station, respectively.

[0072] 2) The output current of the renewable energy power plant and the terminal voltage of the power plant satisfy a specific relationship according to the renewable energy control strategy. For a positive sequence network, the positive sequence current output by each renewable energy power plant... Generally only related to the positive sequence voltage at the station terminal. Related, that is For negative-sequence networks, the output negative-sequence current is only related to the negative-sequence voltage and exhibits an approximately linear relationship under a non-negative-sequence suppression control strategy. or ( (These are constant coefficients). Generally, each station in the positive-sequence network can be described using a function of current versus voltage, while the negative-sequence network can be directly described using impedance, i.e.:

[0073]

[0074] In the formula, and δ i These are the station terminal voltage phasors. The amplitude and phase, and θ i Output current phasors of each station The amplitude and phase, and They are respectively The q-axis and d-axis components in the figure, The impedance represents the equivalent of the negative sequence control characteristic of the station.

[0075] 3) Perform aggregation equivalence on all substations connected to the new energy base's busbar. For negative sequence networks, the new energy base should ultimately be equivalent to a single impedance, the value of which is determined by the impedance of each line within the base. Transformer impedance Equivalent impedance of new energy The decision can be made by calculating the series and parallel values ​​of each impedance based on the specific topological relationship.

[0076] For the positive sequence network, equations (1) and (2) can be combined. Based on the internal line parameters of the base and the relationship between the voltage and output current of each line station, the output current of the entire new energy base corresponding to different voltages of the new energy base's busbar can be obtained through iterative calculation. The specific process is as follows: Figure 3 As shown:

[0077] Step 1: Set the voltage of the new energy base's collecting bus. The amplitude is set, and the voltage phase is set to 0°, then step 2 is executed;

[0078] Step 2: Initialize the station terminal voltage of each station as follows Among them, voltage amplitude and Equal, initialize the output current of each station as follows The amplitude is the rated current of each new energy power station, and then step 3 is executed;

[0079] Step 3: Iterative calculation. According to equation (1), the station terminal voltage of each station in the t-th iteration can be calculated. Furthermore, the station terminal voltage can be calculated according to equation (2). Corresponding station output current Then proceed to step 4;

[0080] Step 4: Determine convergence. If the following formula is satisfied, then convergence is determined (the convergence error value can be adjusted), and proceed to Step 5; otherwise, return to Step 3.

[0081]

[0082] Step 5: Calculate the overall output current of the new energy base based on the output current of each station, and then execute Step 3:

[0083]

[0084] In the formula, and θ Base These are the output current phasor, amplitude, and phase angle of the new energy base, respectively.

[0085] Step 6: Set the bus voltage for different new energy bases Amplitude, repeat step 1, and finally obtain and θ Base The corresponding numerical sequence and characteristic curve.

[0086] 4) In the setting calculation software, it is not necessary to model each station in the new energy base independently. Instead, the new energy base can be regarded as a whole. According to the above process, the voltage-current characteristic curve of the new energy base as a whole is "pre-calculated" before the system-level short-circuit calculation is carried out. Then it is applied to the short-circuit calculation iteration process, which can effectively reduce the matrix calculation dimension and convergence difficulty of the nonlinear link in the short-circuit calculation process. In particular, it has a significant convergence improvement effect for large-scale power systems with large-scale new energy access.

[0087] In one embodiment of the present invention, reference is made to... Figure 2 The typical topology of a new energy base is illustrated using three new energy power stations (referred to as stations 1-3) connected to three different types of photovoltaic / wind turbines in operation on-site. This demonstrates the calculation process and results of the equivalent aggregation of the new energy base. The bus voltage of the new energy base is set to different values ​​(phase angle set to 0°). Following the above process, the output current phasors of the three new energy power stations corresponding to different base bus voltages are calculated, and then superimposed to obtain the amplitude and phase of the base output current. Finally, the voltage-current characteristic curve of the new energy base is obtained. Table 1 shows the main parameters of the example new energy base system.

[0088] The new energy base Figure 4 In the diagram, the red curves representing the output characteristics of each power station show the relationship between the bus voltage of the new energy base and the output current of the power station. (i = 1, 2, 3, the same below), where U N It is the rated voltage of the new energy base, I Ni The black curve represents the rated current of station i; it shows the relationship between the station terminal voltage and the station output current in the corresponding scenario. By superimposing the phasors of the output currents from the three stations, the corresponding curves of the base bus voltage versus the amplitude and phase angle of the base output current are obtained, i.e. and Where I B The reference current is used. In the setting calculation software, by aggregating the equivalent values ​​of each power station within the renewable energy base, the resulting output characteristic curve of the renewable energy base can be directly applied to the iterative process of short-circuit calculation. This aggregates multiple nonlinear constraints of each power station into one, resulting in a significant convergence improvement effect for short-circuit calculation of power systems with large-scale renewable energy access.

[0089] Table 1 Main Parameters of Large-scale New Energy Base

[0090]

[0091] Therefore, based on the voltage and current output characteristics of new energy power plants with different control strategies, this invention proposes an aggregated equivalent modeling method for new energy bases with multiple control strategies. This method reduces the number of nonlinear components in short-circuit calculations of power systems with large-scale new energy, improves the iterative convergence of short-circuit calculations, and thus enhances the accuracy of the setting calculation results for new power systems.

[0092] Exemplary device

[0093] Figure 5 This is a schematic diagram of the structure of a new energy base aggregation equivalent modeling device with multiple control strategies provided in an exemplary embodiment of the present invention. For example... Figure 5 As shown, the device 500 includes:

[0094] The first construction module 510 is used to construct an equivalent model of the relationship between the voltage at the station end of the new energy power plant and the voltage at the bus of the new energy base, which includes multiple control strategies.

[0095] The second construction module 520 is used to construct the positive-order network equivalent model and the negative-order network equivalent model of the new energy power station;

[0096] The first aggregation module 530 is used to perform aggregation equivalence of new energy bases based on the relational equivalence model and the orthogonal network equivalence model, and to obtain the orthogonal network aggregation equivalence model;

[0097] The second aggregation module 540 is used to perform series and parallel aggregation equivalence calculations based on the topological relationship of the new energy base and the negative order network equivalence model, and obtain the negative order network aggregation equivalence model.

[0098] The third construction module 550 is used to construct a new energy base aggregation equivalent model based on the positive order network aggregation equivalent model and the negative order network aggregation equivalent model. The new energy base aggregation equivalent model is used to perform short-circuit calculations on power systems containing new energy bases.

[0099] Optionally, the expression for the relational equivalence model is:

[0100]

[0101] In the formula, and These are the positive and negative sequence voltage phasors of the new energy base's bus hub, respectively. and Let be the positive and negative sequence voltage phasors at the i-th renewable energy power station terminal; and Let be the positive and negative sequence current phasors output by the i-th renewable energy power station, with the positive direction defined as from the power station to the base busbar. and These are the positive and negative sequence impedances of the transmission line from the i-th renewable energy power station, respectively. and These are the positive and negative sequence impedances of the step-up transformer at the i-th renewable energy power station, respectively.

[0102] Optionally, the expression for the orthogonal network equivalence model is:

[0103]

[0104] In the formula, and δ i These are the station terminal voltage phasors. The amplitude and phase, and θ i Output current phasors of each station The amplitude and phase, and They are respectively The q-axis and d-axis components in the figure.

[0105] Optionally, the expression for the negative order network equivalent model is:

[0106] or

[0107] In the formula, The impedance K represents the equivalent of the negative sequence control characteristic of the station. - The slope is the equal value slope after approximating the voltage-current relationship in the negative sequence control characteristic as a linear relationship.

[0108] Optionally, the first aggregation module 530 includes:

[0109] Step 1: Set the voltage of the new energy base's collecting bus. The amplitude is set, and the voltage phase is set to 0°, then step 2 is executed;

[0110] Step 2: Initialize the station terminal voltage of each station as follows The voltage amplitude is related to the voltage of the busbar of the new energy base. Equal, initialize the output current of each station as follows The amplitude is the rated current of each new energy power station, and then step 3 is executed;

[0111] Step 3: Iterative calculation. Based on the expression of the relational equivalent model, the station terminal voltage in the t-th iteration can be calculated. Furthermore, the station terminal voltage can be calculated based on the expression of the positive sequence network equivalent model. Corresponding station output current Then proceed to step 4;

[0112] Step 4: Determine convergence. If the station terminal voltages in the t-th iteration and the station terminal voltages in the (t-1)-th iteration satisfy the preset convergence criterion, then convergence is determined and step 5 is executed; otherwise, return to step 3.

[0113] Step 5: Calculate the overall output current of the new energy base based on the output current of each station, and then proceed to Step 6:

[0114] Step 6: Set the bus voltage for different new energy bases Amplitude, repeat step 1, and finally obtain and θ Base The corresponding numerical sequence of relations is used to characterize the orthogonal network aggregation equivalent model.

[0115] Optionally, the convergence criterion can be expressed as:

[0116]

[0117] In the formula, ε i This represents the difference between the station-end voltage of the i-th power station in the two iterations.

[0118] Optionally, the formula for calculating the overall output current is:

[0119]

[0120] In the formula, and θ Base These are the phasor, amplitude, and phase angle of the overall output current of the new energy base.

[0121] Exemplary electronic devices

[0122] Figure 6 This is the structure of an electronic device provided in an exemplary embodiment of the present invention. For example... Figure 6 As shown, the electronic device 60 includes one or more processors 61 and a memory 62.

[0123] The processor 61 may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0124] The memory 62 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 61 may execute the program instructions to implement the methods of the software programs of the various embodiments of the present invention described above, and / or other desired functions. In one example, the electronic device may also include an input device 63 and an output device 64, these components being interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0125] In addition, the input device 63 may also include, for example, a keyboard, a mouse, etc.

[0126] The output device 64 can output various information to the outside. The output device 64 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0127] Of course, for the sake of simplicity, Figure 6 Only some of the components of this electronic device relevant to the present invention are shown, omitting components such as buses, input / output interfaces, etc. In addition, the electronic device may include any other suitable components depending on the specific application.

[0128] Exemplary computer program products and computer-readable storage media

[0129] In addition to the methods and apparatus described above, embodiments of the present invention may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the methods according to various embodiments of the present invention described in the "Exemplary Methods" section above.

[0130] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of the present invention. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0131] Furthermore, embodiments of the present invention may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps of the methods according to various embodiments of the present invention described in the "Exemplary Methods" section above.

[0132] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0133] The basic principles of the present invention have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in the present invention are merely examples and not limitations, and should not be considered as essential features of each embodiment of the present invention. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the present invention to the necessity of employing the aforementioned specific details.

[0134] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For system embodiments, since they largely correspond to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0135] The block diagrams of devices, systems, devices, and systems involved in this invention are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, systems, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0136] The methods and systems of the present invention may be implemented in many ways. For example, they may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order of steps for the methods is for illustrative purposes only, and the steps of the methods of the present invention are not limited to the order specifically described above unless otherwise specifically stated. Furthermore, in some embodiments, the present invention may also be implemented as a program recorded on a recording medium, the program comprising machine-readable instructions for implementing the methods according to the present invention. Thus, the present invention also covers recording media storing programs for performing the methods according to the present invention.

[0137] It should also be noted that in the systems, apparatus, and methods of the present invention, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered equivalents of the present invention. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the invention. Therefore, the invention is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0138] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the invention to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for aggregated equivalent modeling of new energy bases containing multiple control strategies, characterized in that, include: Construct an equivalent model of the relationship between the voltage at the station end of a new energy power plant and the voltage at the busbar of the new energy base, which includes multiple control strategies; Construct positive-order and negative-order network equivalent models for new energy power plants; Based on the relational equivalence model and the orthogonal network equivalence model, the aggregation equivalence of the new energy base is performed to obtain the orthogonal network aggregation equivalence model; Based on the topological relationship of the new energy base and the negative order network equivalent model, a series-parallel aggregation equivalent calculation is performed to obtain the negative order network aggregation equivalent model; Based on the positive-order network aggregation equivalent model and the negative-order network aggregation equivalent model, a new energy base aggregation equivalent model is constructed, wherein the new energy base aggregation equivalent model is used to perform short-circuit calculations on power systems containing new energy bases; Based on the aforementioned relational equivalence model and the aforementioned orthogonal network equivalence model, the aggregation equivalence of the new energy base is performed to obtain the orthogonal network aggregation equivalence model, including: Step 1: Set the positive sequence voltage phasor of the new energy base's bus hub. The amplitude is set, and the voltage phase is set to 0°, then step 2 is executed; Step 2: Initialize the station terminal voltage of each station as follows The voltage amplitude is related to the voltage of the busbar of the new energy base. Equal, initialize the output current of each station as follows The amplitude is the rated current of each new energy power station, and then step 3 is executed; Step 3: Iterative calculation. Based on the expression of the relational equivalent model, the station terminal voltage in the t-th iteration can be calculated. Furthermore, the station terminal voltage can be calculated based on the expression of the orthogonal sequence network equivalent model. Corresponding station output current Then proceed to step 4, where, and These are the station terminal voltage phasors. The amplitude and phase, and Output current phasors of each station The amplitude and phase; Step 4: Determine convergence. If the station terminal voltages in the t-th iteration and the station terminal voltages in the (t-1)-th iteration satisfy the preset convergence criterion, then convergence is determined and step 5 is executed; otherwise, return to step 3. Step 5: Calculate the overall output current of the new energy base based on the output current of each station, and then proceed to Step 6: Step 6: Set the bus voltage for different new energy bases Amplitude, repeat step 1, and finally obtain and , The corresponding numerical sequence of relationships is used to characterize the positive order network aggregation equivalence model. and These represent the overall output current amplitude and phase angle of the new energy base, respectively.

2. The method according to claim 1, characterized in that, The expression for the relational equivalence model is: In the formula, and These are the positive and negative sequence voltage phasors of the new energy base's bus hub, respectively. and For the first i Positive and negative sequence voltage phasors at the terminal of a new energy power station; and For the first i The positive-sequence and negative-sequence current phasors output by each new energy power station are defined with the positive direction pointing from the power station to the base busbar. and They are the first i The positive and negative sequence impedances of the transmission lines from each new energy power station. and They are the first i The positive and negative sequence impedances of the boost transformer at each new energy power station.

3. The method according to claim 1, characterized in that, The expression for the orthogonal order network equivalence model is: In the formula, and These are the station terminal voltage phasors. The amplitude and phase, and Output current phasors of each station The amplitude and phase, and They are respectively The q-axis and d-axis components in the figure.

4. The method according to claim 1, characterized in that, The expression for the negative order network equivalent model is: or In the formula, The impedance representing the equivalent of the negative sequence control characteristic of the station. The slope is the equal value slope after approximating the voltage-current relationship in the negative sequence control characteristic as a linear relationship.

5. The method according to claim 1, characterized in that, The expression for the convergence criterion is: In the formula, For the first i The difference between the station terminal voltages of each station in the results of two consecutive iterations.

6. The method according to claim 1, characterized in that, The formula for calculating the overall output current is: In the formula, , and These are the phasor, amplitude, and phase angle of the overall output current of the new energy base.

7. A device for aggregated equivalent modeling of new energy bases containing multiple control strategies, used to implement the method described in claim 1, characterized in that, include: The first construction module is used to construct an equivalent model of the relationship between the voltage at the station end of the new energy power plant and the voltage at the bus of the new energy base, which includes multiple control strategies. The second construction module is used to construct the positive-order network equivalent model and the negative-order network equivalent model of the new energy power station; The first aggregation module is used to perform aggregate equivalence of the new energy base based on the relational equivalence model and the orthogonal network equivalence model, and obtain the orthogonal network aggregate equivalence model; The second aggregation module is used to perform serial and parallel aggregation equivalence calculations based on the topological relationship of the new energy base and the negative order network equivalence model to obtain the negative order network aggregation equivalence model. The third construction module is used to construct a new energy base aggregation equivalent model based on the positive order network aggregation equivalent model and the negative order network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short-circuit calculations on the power system containing the new energy base.

8. A computer-readable storage medium, characterized in that, The storage medium stores a computer program for performing the method described in any one of claims 1-6.

9. An electronic device, characterized in that, The electronic device includes: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1-6.

Images