New energy base aggregation equivalent modeling method containing multiple control strategies

Abstract

The invention discloses an aggregation equivalent modeling method for a new energy base containing multiple control strategies. The method comprises the following steps: constructing a relation equivalent model satisfied by the terminal voltage of a new energy field station of the new energy base containing multiple control strategies and the voltage of a collection bus of the new energy base; constructing a positive sequence network equivalent model and a negative sequence network equivalent model of the new energy station; performing aggregation equivalence of the new energy base according to the relation equivalence model and the positive sequence network equivalence model to obtain a positive sequence network aggregation equivalence model; performing series-parallel aggregation equivalent calculation according to the topological relation of the new energy base and the negative sequence network equivalent model to obtain a negative sequence network aggregation equivalent model; and according to the positive sequence network aggregation equivalence model and the negative sequence network aggregation equivalence model, a new energy base aggregation equivalence model is constructed, and the new energy base aggregation equivalence model is used for performing short circuit calculation on the power system containing the new energy base.

Description

Technical Field

[0001] The present invention relates to the field of relay protection setting calculation technology, and more specifically, to an aggregate equivalent modeling method for a new energy base containing multiple control strategies. Background Art

[0002] As the first line of defense for the power system, relay protection relies on setting calculation to provide a basis for setting fixed values, so as to achieve efficient coordination between protection levels, ensure rapid fault isolation and safe and stable operation of the system. Compared with conventional power sources, new energy sources show strong controllability during faults. Therefore, voltage-controlled current sources and other forms of equivalent new energy sources have been gradually adopted in the main grid protection setting calculation software, and short-circuit calculations are realized through iterative methods. In this process, the iterative convergence of short-circuit calculations will decrease with the increase in the number of new energy nodes. Therefore, it is necessary to aggregate and equalize new energy to reduce the number of new energy nodes in short-circuit calculations in power systems with large-scale new energy access. At present, in short-circuit calculations, new energy equivalent modeling can only achieve station-level aggregation of new energy sources of the same type and the same control strategy. The aggregation level is far from enough. It is necessary to be able to aggregate large-scale new energy bases with different new energy types and control strategies, which will greatly improve the iterative convergence of short-circuit calculations and make it possible to quickly and accurately set the power system with large-scale new energy. However, various types of wind turbines and photovoltaic power generation units have different fault response characteristics. They are affected by different spatial locations, different fault characteristics, and access topologies, making it difficult to set and calculate aggregation values. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides an aggregate equivalent modeling method for new energy bases containing multiple control strategies.

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

[0005] Construct an equivalent model of the relationship between the terminal voltage of a new energy station and the bus voltage of a new energy base containing multiple control strategies;

[0006] Construct positive-sequence network equivalent models and negative-sequence network equivalent models for new energy stations;

[0007] Perform aggregation equivalence of new energy bases according to the relational equivalence model and the positive-sequence network equivalence model to obtain the positive-sequence network aggregation equivalence model;

[0008] According to the topological relationship of the new energy base and the negative sequence network equivalent model, the series-parallel aggregation equivalent calculation is performed to obtain the negative sequence network aggregation equivalent model;

[0009] According to the positive-sequence network aggregation equivalent model and the negative-sequence 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 calculation on the power system containing the new energy base.

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

[0011]

[0012] In the formula, and They are the positive and negative sequence voltage phasors of the busbar collected by the new energy base, and are the positive-sequence and negative-sequence voltage phasors at the i-th renewable energy station; and are the positive and negative sequence current phasors output by the i-th new energy station, and the positive direction is set from the station to the base collection bus. and are the positive-sequence and negative-sequence impedances of the transmission line of the i-th renewable energy station, and They are the positive-sequence and negative-sequence impedances of the boost transformer of the i-th renewable energy station.

[0013] Optionally, the expression of the positive sequence network equivalent model is:

[0014]

[0015] In the formula, and δ i They are the voltage phasors at the station terminals The magnitude and phase of and θ i Output current phasor of each station The magnitude and phase of and They are The q-axis and d-axis components in .

[0016] Alternatively, the expression of the negative sequence network equivalent model is:

[0017] or

[0018] In the formula, Indicates the impedance equivalent to the negative sequence control characteristic of the station, K - It is the equivalent slope after the voltage-current relationship in the negative sequence control characteristic is approximated as a linear relationship.

[0019] Optionally, performing aggregation equivalence of new energy bases according to the relational equivalence model and the positive-sequence network equivalence model to obtain the positive-sequence network aggregation equivalence model includes:

[0020] Step 1: Set the bus voltage of the new energy base amplitude, and set the voltage phase to 0°, and then execute step 2;

[0021] Step 2: Initialize the voltage at each station to The voltage amplitude is similar to the bus voltage of the new energy base Equal, initialize the output current of each station to The amplitude is the rated current of each new energy station, and then execute step 3;

[0022] Step 3: Iterative calculation: According to the expression of the relational equivalent model, the voltage at each station in the tth 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 terminal voltages of each station in the t-th iteration and the terminal voltages of each station in the t-1-th iteration meet the preset convergence criteria, 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 of different new energy bases Amplitude, repeat step 1, and finally get and θ Base The corresponding relationship numerical sequence is used to characterize the positive sequence network aggregation equivalence model according to the relationship numerical sequence.

[0026] Optionally, the expression of the convergence criterion is:

[0027]

[0028] In the formula, ε i is the difference between the two iterative results of the terminal voltage of the ith station.

[0029] Optionally, the overall output current is calculated as:

[0030]

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

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

[0033] The first construction module is used to construct an equivalent model of the relationship between the terminal voltage of a new energy station containing multiple control strategies and the bus voltage of the new energy base;

[0034] The second construction module is used to construct a positive sequence network equivalent model and a negative sequence network equivalent model of a new energy station;

[0035] The first aggregation module is used to perform aggregation equivalence of new energy bases according to the relationship equivalence model and the positive sequence network equivalence model to obtain the positive sequence network aggregation equivalence model;

[0036] The second aggregation module is used to perform series-parallel aggregation equivalent calculation according to the topological relationship of the new energy base and the negative-sequence network equivalent model to obtain the negative-sequence network aggregation equivalent model;

[0037] The third construction module is used to construct a new energy base aggregation equivalent model based on the positive sequence network aggregation equivalent model and the negative sequence network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short circuit calculation 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, wherein the storage medium stores a computer program, and the computer program is used to execute the method described in any one of the above aspects of the present invention.

[0039] According to another aspect of the present invention, an electronic device is provided, comprising: a processor; a memory for storing instructions executable by the processor; 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 the above aspects of the present invention.

[0040] Therefore, based on the voltage and current output characteristics of new energy stations with different control strategies, the present invention proposes an aggregated equivalent modeling method for new energy bases containing multiple control strategies, reduces the number of nonlinear elements in short-circuit calculations of power systems containing large-scale new energy, improves the iterative convergence of short-circuit calculations, and thus improves the accuracy of setting calculation results of new power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0042] Figure 1It is a flow chart of a method for modeling new energy base aggregation equivalent values ​​including multiple control strategies provided by an exemplary embodiment of the present invention;

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

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

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

[0046] Figure 5 It is a structural schematic diagram of a new energy base aggregation equivalent modeling device including multiple control strategies provided by an exemplary embodiment of the present invention;

[0047] Figure 6 This is a structure of an electronic device provided by an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0048] Below, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described here.

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

[0050] Those skilled in the art can understand that the terms "first" and "second" in the embodiments of the present invention are only used to distinguish different steps, devices or modules, etc., and neither represent any specific technical meaning nor indicate the necessary logical order between them.

[0051] It should also be understood that, in the embodiments of the present invention, “plurality” may refer to two or more than two, and “at least one” may refer to one, two or more than two.

[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 limited or otherwise indicated in the context.

[0053] In addition, the term "and / or" in the present invention is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects before and after are in an "or" relationship.

[0054] It should also be understood that the description of the various embodiments of the present invention focuses on the differences between the various embodiments, and the same or similar aspects thereof can be referenced to each other, and for the sake of brevity, they will not be described one by one.

[0055] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

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

[0057] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

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

[0059] Embodiments of the present invention can be applied to electronic devices such as terminal devices, computer systems, servers, etc., which can operate with many other general or special computing system environments or configurations. Examples of well-known terminal devices, computing systems, environments and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, servers, etc. 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 personal computers, small computer systems, large computer systems, and distributed cloud computing technology environments including any of the above systems, etc.

[0060] Electronic devices such as terminal devices, computer systems, servers, etc. can be described in the general context of computer system executable instructions (such as program modules) executed by computer systems. Generally, 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 a distributed cloud computing environment, where tasks are performed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules can be located on local or remote computing system storage media including storage devices.

[0061] Exemplary Methods

[0062] Figure 1 1 is a flow chart of a method for modeling a new energy base aggregation equivalent value including multiple control strategies provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as Figure 1 As shown, the new energy base aggregation equivalent modeling method 100 including multiple control strategies includes the following steps:

[0063] Step 101, constructing an equivalent model of the relationship between the terminal voltage of a new energy station containing multiple control strategies and the bus voltage of the new energy base;

[0064] Step 102, constructing a positive-sequence network equivalent model and a negative-sequence network equivalent model of a new energy station;

[0065] Step 103, performing aggregation equivalence of the new energy bases according to the relational equivalence model and the positive sequence network equivalence model, and obtaining the positive sequence network aggregation equivalence model;

[0066] Step 104, performing series-parallel aggregation equivalent calculation according to the topological relationship of the new energy base and the negative-sequence network equivalent model to obtain the negative-sequence network aggregation equivalent model;

[0067] Step 105, constructing a new energy base aggregation equivalent model according to the positive sequence network aggregation equivalent model and the negative sequence network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short circuit calculation on the power system containing the new energy base.

[0068] Specifically, Figure 2 The typical topology diagram of a new energy base shown in the figure is a collection of multiple new energy stations through different transmission lines. The types of stations, total capacity and control characteristics included in it are different, and they are generally collected through different lines to the substation collection bus of the same voltage level. It is impossible to use the traditional single-machine multiplication idea to equalize their output characteristics. A new energy base aggregation equivalent modeling method containing multiple control strategies suitable for power system short-circuit calculation is proposed. The steps are as follows:

[0069] 1) Assume that the aggregation equivalent modeling scope of the new energy base is the station transmission line collection bus and its connected lower-level new energy system, ignoring the capacitance current of the transmission line to the ground, and the following expression is established:

[0070]

[0071] In the formula, and They are the positive and negative sequence voltage phasors of the busbar collected by the new energy base, and are the positive-sequence and negative-sequence voltage phasors at the i-th renewable energy station; and are the positive and negative sequence current phasors output by the i-th new energy station, and the positive direction is set from the station to the base collection bus. and are the positive-sequence and negative-sequence impedances of the transmission line of the i-th renewable energy station, and They are the positive-sequence and negative-sequence impedances of the boost transformer of the i-th renewable energy station.

[0072] 2) The output current of the new energy station and the voltage at the station end meet a specific relationship according to the control strategy of the new energy. For the positive sequence network, the positive sequence current output by each new energy station Generally only related to the positive sequence voltage at the station end Related, that is, For the negative sequence network, the output negative sequence current is only related to the negative sequence voltage and is approximately linearly related under the control strategy without negative sequence suppression, that is, or ( is a constant coefficient). In general, each station in the positive sequence network can be described by the function form of current to voltage, and the negative sequence network can be directly described by impedance form, that is:

[0073]

[0074] In the formula, and δ i They are the voltage phasors at the station terminals The magnitude and phase of and θ i Output current phasor of each station The magnitude and phase of and They are The q-axis and d-axis components in It represents the impedance equivalent to the negative sequence control characteristic of the station.

[0075] 3) Carry out aggregation and equalization of each station connected to the new energy base busbar. For the negative sequence network, the new energy base should eventually be equivalent to an impedance, and the impedance value is determined by the impedance of each line in the base. Transformer impedance And the new energy equivalent impedance The decision can be made by calculating the series and parallel connection of each impedance value according to the specific topological relationship.

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

[0077] Step 1: Set the bus voltage of the new energy base amplitude, and set the voltage phase to 0°, and then execute step 2;

[0078] Step 2: Initialize the voltage at each station to The voltage amplitude and Equal, initialize the output current of each station to The amplitude is the rated current of each new energy station, and then execute step 3;

[0079] Step 3: Iterative calculation: According to formula (1), the terminal voltage of each station in the tth iteration can be calculated: The station terminal voltage can be further calculated according to formula (2): Corresponding station output current Then proceed to step 4;

[0080] Step 4: Determine convergence. If the following equation is satisfied, then convergence is determined (the convergence error value can be adjusted), and step 5 is executed. 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 They are the output current phasor, amplitude and phase angle of the new energy base respectively.

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

[0086] 4) In the setting calculation software, there is no need to independently model each site in the new energy base. 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, and then applied to the short-circuit calculation iterative process. This can effectively reduce the matrix calculation dimension and convergence difficulty of the nonlinear link in the short-circuit calculation process, especially for large-scale power systems with large-scale new energy access. It has a significant convergence improvement effect.

[0087] In one embodiment of the present invention, referring to Figure 2 The topological structure of a typical new energy base, the three connected new energy sites are respectively taken as examples of three types of photovoltaic / wind turbines put into operation in the field project (recorded as sites 1 to 3), to illustrate the calculation process and results of the equivalent aggregation of the new energy base, set the bus voltage of the new energy base to different values ​​(the phase angle is set to 0°), and calculate the output current phasors of the three new energy sites corresponding to the bus voltage of the different bases according to the above process, and obtain the base output current amplitude and phase after superposition, and finally obtain the voltage-current characteristic curve of the new energy base. Table 1 shows the main parameters in the example new energy base system.

[0088] New energy base in Figure 4 In the figure, the red curve of the output characteristics of each station is the corresponding relationship between the bus voltage of the new energy base and the output current of the station, that is, (i=1,2,3, the same below), where U N is the rated voltage of the new energy base, I Ni is the rated current of station i; the black curve is the corresponding relationship between the station terminal voltage and the station output current in the corresponding scenario, that is, The output current phasors of the three stations are superimposed to obtain the corresponding curves of the base bus voltage and the base output current amplitude and phase angle, namely: and Among them I B In the setting calculation software, by aggregating the equivalent values ​​of each station in the new energy base, the output characteristic curve of the new energy base can be directly applied to the iterative process of short-circuit calculation, aggregating multiple nonlinear constraints of each station into one, which will have a significant convergence improvement effect on the short-circuit calculation of the power system with large-scale new energy access.

[0089] Table 1 Main parameters of large-scale new energy bases

[0090]

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

[0092] Exemplary Devices

[0093] Figure 5 1 is a schematic diagram of a structure of a new energy base aggregation equivalent modeling device including multiple control strategies provided by an exemplary embodiment of the present invention. 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 terminal voltage of the new energy station and the bus voltage of the new energy base containing multiple control strategies;

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

[0096] The first aggregation module 530 is used to aggregate and equalize the new energy bases according to the relationship equivalence model and the positive sequence network equivalence model to obtain the positive sequence network aggregation equivalence model;

[0097] The second aggregation module 540 is used to perform series-parallel aggregation equivalent calculation according to the topological relationship of the new energy base and the negative-sequence network equivalent model to obtain the negative-sequence network aggregation equivalent model;

[0098] The third construction module 550 is used to construct a new energy base aggregation equivalent model according to the positive sequence network aggregation equivalent model and the negative sequence network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short circuit calculation on the power system containing the new energy base.

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

[0100]

[0101] In the formula, and They are the positive and negative sequence voltage phasors of the busbar collected by the new energy base, and are the positive-sequence and negative-sequence voltage phasors at the i-th renewable energy station; and are the positive and negative sequence current phasors output by the i-th new energy station, and the positive direction is set from the station to the base collection bus. and are the positive-sequence and negative-sequence impedances of the transmission line of the i-th renewable energy station, and They are the positive-sequence and negative-sequence impedances of the boost transformer of the i-th renewable energy station.

[0102] Optionally, the expression of the positive sequence network equivalent model is:

[0103]

[0104] In the formula, and δ i They are the voltage phasors at the station terminals The magnitude and phase of and θ i Output current phasor of each station The magnitude and phase of and They are The q-axis and d-axis components in .

[0105] Alternatively, the expression of the negative sequence network equivalent model is:

[0106] or

[0107] In the formula, Indicates the impedance equivalent to the negative sequence control characteristic of the station, K - It is the equivalent slope after the voltage-current relationship in the negative sequence control characteristic is approximated as a linear relationship.

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

[0109] Step 1: Set the bus voltage of the new energy base amplitude, and set the voltage phase to 0°, and then execute step 2;

[0110] Step 2: Initialize the voltage at each station to The voltage amplitude is similar to the bus voltage of the new energy base Equal, initialize the output current of each station to The amplitude is the rated current of each new energy station, and then execute step 3;

[0111] Step 3: Iterative calculation: According to the expression of the relational equivalent model, the voltage at each station in the tth 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 terminal voltages of each station in the t-th iteration and the terminal voltages of each station in the t-1-th iteration meet the preset convergence criteria, 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 of different new energy bases Amplitude, repeat step 1, and finally get and θ Base The corresponding relationship numerical sequence is used to characterize the positive sequence network aggregation equivalence model according to the relationship numerical sequence.

[0115] Optionally, the expression of the convergence criterion is:

[0116]

[0117] In the formula, ε i is the difference between the two iterative results of the terminal voltage of the ith station.

[0118] Optionally, the overall output current is calculated as:

[0119]

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

[0121] Exemplary Electronic Devices

[0122] Figure 6 This is a structure of an electronic device provided by an exemplary embodiment of the present invention. 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 forms of processing units having data processing capabilities 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, and the computer program product 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 (cache), etc. 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 run 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, which are 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, and can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto.

[0127] Of course, to simplify, Figure 6 Only some of the components related to the present invention in the electronic device are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, the electronic device may further include any other appropriate components according to specific application conditions.

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

[0129] In addition to the above-mentioned methods and devices, an embodiment of the present invention may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present invention described in the above-mentioned "Exemplary Method" section of this specification.

[0130] The computer program product may be written in any combination of one or more programming languages ​​to write program code for performing the operations of the embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0131] In addition, an embodiment of the present invention may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present invention described in the above “Exemplary Method” section of this specification.

[0132] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, system or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0133] The basic principle of the present invention is described above in conjunction with specific embodiments. However, it should be pointed out that the advantages, strengths, effects, etc. mentioned in the present invention are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. must be possessed by each embodiment of the present invention. In addition, the specific details disclosed above are only for the purpose of illustration and facilitation of understanding, rather than limitation, and the above details do not limit the present invention to being implemented by adopting the above specific details.

[0134] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0135] The block diagrams of the devices, systems, equipment, and systems involved in the present invention are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, systems, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0136] The method and system of the present invention may be implemented in many ways. For example, the method and system of the present invention may be implemented by software, hardware, firmware or any combination of software, hardware, firmware. The above order of steps for the method is only for illustration, and the steps of the method of the present invention are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present invention may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present invention. Thus, the present invention also covers a recording medium storing a program for executing the method according to the present invention.

[0137] It should also be noted that in the system, device and method of the present invention, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent schemes of the present invention. The above description of the disclosed aspects is provided to enable any technician in the field to make or use the present invention. Various modifications to these aspects are very obvious to those skilled in the art, and the general principles defined here can be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown here, but in accordance with the widest range consistent with the principles and novel features disclosed here.

[0138] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A new energy base aggregation equivalent modeling method containing multiple control strategies, characterized in that: include: Construct an equivalent model of the relationship between the terminal voltage of a new energy station and the bus voltage of a new energy base containing multiple control strategies; Construct positive-sequence network equivalent models and negative-sequence network equivalent models for new energy stations; Perform aggregation equivalence of the new energy base according to the relationship equivalence model and the positive sequence network equivalence model to obtain a positive sequence network aggregation equivalence model; Perform series-parallel aggregation equivalent calculation according to the topological relationship of the new energy base and the negative-sequence network equivalent model to obtain a negative-sequence network aggregation equivalent model; A new energy base aggregation equivalent model is constructed according to the positive sequence network aggregation equivalent model and the negative sequence network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short circuit calculation on the power system containing the new energy base.

2. The method according to claim 1, characterized in that The expression of the relational equivalence model is: In the formula, and They are the positive and negative sequence voltage phasors of the busbar collected by the new energy base, and are the positive-sequence and negative-sequence voltage phasors at the i-th renewable energy station; and are the positive and negative sequence current phasors output by the i-th new energy station, and the positive direction is set from the station to the base collection bus. and are the positive-sequence and negative-sequence impedances of the transmission line of the i-th renewable energy station, and They are the positive-sequence and negative-sequence impedances of the boost transformer of the i-th renewable energy station.

3. The method according to claim 1, characterized in that The expression of the positive sequence network equivalent model is: In the formula, and δ i They are the voltage phasors at the station terminals The magnitude and phase of and θ i Output current phasor of each station The magnitude and phase of and They are The q-axis and d-axis components in .

4. The method according to claim 1, characterized in that: The expression of the negative sequence network equivalent model is: In the formula, Indicates the impedance equivalent to the negative sequence control characteristic of the station, K - It is the equivalent slope after the voltage-current relationship in the negative sequence control characteristic is approximated as a linear relationship.

5. The method according to claim 1, characterized in that Performing aggregation equivalence of the new energy base according to the relationship equivalence model and the positive sequence network equivalence model to obtain the positive sequence network aggregation equivalence model includes: Step 1: Set the bus voltage of the new energy base amplitude, and set the voltage phase to 0°, and then execute step 2; Step 2: Initialize the voltage at each station to The voltage amplitude is similar to the bus voltage of the new energy base Equal, initialize the output current of each station to The amplitude is the rated current of each new energy station, and then execute step 3; Step 3: Iterative calculation: According to the expression of the relational equivalent model, the voltage at each station in the tth 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; Step 4: Determine convergence. If the terminal voltages of each station in the t-th iteration and the terminal voltages of each station in the t-1-th iteration meet the preset convergence criteria, 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 of different new energy bases Amplitude, repeat step 1, and finally get and θ Base The corresponding relationship numerical sequence is used to characterize the positive sequence network aggregation equivalence model according to the relationship numerical sequence.

6. The method according to claim 5, characterized in that The expression of the convergence criterion is: In the formula, ε i is the difference between the two iterative results of the terminal voltage of the ith station.

7. The method according to claim 5, characterized in that The calculation formula of the overall output current is: In the formula, and θ Base They are the overall output current phasor, amplitude and phase angle of the new energy base respectively.

8. A new energy base aggregation equivalent modeling device containing multiple control strategies, characterized in that: include: The first construction module is used to construct an equivalent model of the relationship between the terminal voltage of a new energy station containing multiple control strategies and the bus voltage of the new energy base; The second construction module is used to construct a positive sequence network equivalent model and a negative sequence network equivalent model of a new energy station; A first aggregation module is used to perform aggregation equivalence of the new energy base according to the relationship equivalence model and the positive sequence network equivalence model to obtain a positive sequence network aggregation equivalence model; A second aggregation module is used to perform series-parallel aggregation equivalent calculation according to the topological relationship of the new energy base and the negative-sequence network equivalent model to obtain the negative-sequence network aggregation equivalent model; The third construction module is used to construct a new energy base aggregation equivalent model based on the positive sequence network aggregation equivalent model and the negative sequence network aggregation equivalent model, wherein the new energy base aggregation equivalent model is used to perform short circuit calculation on the power system containing the new energy base.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and the computer program is used to execute the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: The electronic device comprises: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1 to 7.

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