A grid optimization adjustment method and device for improving the short-circuit ratio of multiple renewable energy stations

Abstract

The present invention provides a grid optimization and adjustment method and device for improving the short-circuit ratio of multiple renewable energy stations. The method identifies unqualified nodes based on their short-circuit ratios under a basic grid operation mode, divides them into subnetworks, identifies shortest paths, and determines a candidate branch set. A candidate operation mode set is generated based on the basic grid operation mode and the branches in the candidate branch set. The effectiveness of each candidate operation mode is determined based on the short-circuit capacity and equivalent capacity changes of unqualified busbar nodes in the set of unqualified nodes with unqualified short-circuit ratios for multiple renewable energy stations under each candidate operation mode and under the basic operation mode, thereby generating a grid optimization and adjustment strategy set. The method automatically generates effective grid optimization and adjustment strategies for improving the short-circuit ratio of multiple renewable energy stations.

Description

Technical Field

[0001] The present invention relates to the technical field of safety and stability analysis and control of new energy power systems, and more specifically, to a grid optimization adjustment method and device for improving the short-circuit ratio of multiple renewable energy stations. Background Art

[0002] In recent years, renewable energy generation equipment, represented by wind power and photovoltaics, has been connected to the power grid on a large scale. Most existing renewable energy generation equipment uses a control mode that tracks the grid voltage, requiring the AC grid to provide voltage support. The short-circuit ratio of multiple renewable energy stations is a key indicator of voltage support. In practice, several areas with high renewable energy penetration have experienced high rates of substandard short-circuit ratios at multiple renewable energy stations, necessitating urgent research into control measures to improve this ratio.

[0003] Currently, research on the short-circuit ratio of multiple renewable energy stations primarily focuses on its rational definition and calculation methods, while research on control measures to improve this ratio is relatively lacking. Engineering methods for improving the short-circuit ratio of multiple renewable energy stations primarily rely on trial-and-error based on expert experience, which suffers from high labor costs and difficulty in obtaining optimized solutions. There is also a lack of optimized control methods and systems specifically designed to improve the short-circuit ratio of multiple renewable energy stations. Current power grid planning simulation software systems lack support for decision-making regarding improving the short-circuit ratio of multiple renewable energy stations.

[0004] In principle, the grid structure and connection method in the renewable energy grid connection area will affect the short-circuit ratio of the system's renewable energy multi-stations. These factors will directly lead to changes in short-circuit capacity, and thus changes in the short-circuit ratio at the grid connection point. Therefore, during the operation phase, consideration can be given to changing the grid connection method and switching the maintenance line's commissioning and decommissioning status. By reducing the equivalent impedance of the renewable energy grid connection point system and increasing the grid connection point's short-circuit capacity, the short-circuit ratio at the grid connection point can be improved. During the planning phase, the goal of increasing the short-circuit ratio at the grid connection point can be achieved by adding new transmission lines and transformers in the grid connection point area.

[0005] Therefore, it is urgent to study and propose a control method for improving the short-circuit ratio of multiple renewable energy stations based on grid optimization and adjustment, and to develop corresponding auxiliary decision-making devices, so as to improve the safe and stable operation level of power grids and renewable energy stations. Summary of the Invention

[0006] In order to solve the technical problems in the prior art of lacking an optimization control method and system aimed at improving the short-circuit ratio of multiple renewable energy stations, and in which the power grid planning simulation software system does not have a decision-making support function for improving the short-circuit ratio of multiple renewable energy stations, the present invention provides a grid optimization adjustment method and device for improving the short-circuit ratio of multiple renewable energy stations.

[0007] According to one aspect of the present invention, a method for optimizing and adjusting a grid structure for improving the short-circuit ratio of multiple renewable energy stations is provided. The method comprises:

[0008] Step 1-1: constructing a digital model of a power grid simulation including multiple renewable energy stations, wherein the digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, wherein the power grid flow simulation component data model constitutes a basic power grid operation mode, and the power grid flow simulation component data model includes a renewable energy station model, wherein the renewable energy station model includes a renewable energy power generation unit;

[0009] Step 1-2: Based on the short-circuit ratio calculation formula, the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio are calculated according to the operating parameters of the bus node of each new energy station under the basic power grid operation mode, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes;

[0010] Steps 1-3: Based on the set unqualified node judgment rules, determine the unqualified nodes of the new energy multi-station short circuit ratio according to the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and generate a set of unqualified nodes of the new energy multi-station short circuit ratio;

[0011] Step 1-4: Based on the set sub-network grouping rules, at least one sub-network set is generated according to the mutual impedance modulus values ​​of any two bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes and the set modulus threshold;

[0012] Steps 1-5: For any two bus nodes in each subnetwork set, the shortest path between the two bus nodes is calculated based on the grid branch impedance between the two bus nodes, and a candidate branch set of the grid is determined based on the number of occurrences of the branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation component data model;

[0013] Step 1-6, generating a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set;

[0014] Step 1-7, based on the short-circuit ratio calculation formula, calculate the corresponding short-circuit capacity and equivalent capacity according to the operating parameters of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes included in each candidate operating mode in the candidate operating mode set;

[0015] Steps 1-8 determine the effectiveness result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with new energy multi-station short-circuit ratios contained in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generate a grid optimization adjustment strategy set based on the effectiveness results, wherein the effectiveness results include valid operating modes and invalid operating modes.

[0016] According to another aspect of the present invention, a grid optimization and adjustment device for improving the short-circuit ratio of multiple renewable energy stations is provided, the device comprising:

[0017] A model construction module, configured to construct a digital model of a power grid simulation including multiple renewable energy stations, wherein the digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, the power grid flow simulation component data model constituting a basic power grid operation mode, the power grid flow simulation component data model including a renewable energy station model, and the renewable energy station model including a renewable energy power generation unit;

[0018] A first calculation module is used to calculate the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio of the bus node of each new energy station based on the short-circuit ratio calculation formula and the operating parameters of the bus node under the basic power grid operation mode, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes;

[0019] The first set module is used to determine the unqualified nodes of the new energy multi-station short circuit ratio based on the set unqualified node judgment rules and the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and generate a set of unqualified nodes of the new energy multi-station short circuit ratio;

[0020] The second set module is used to generate at least one sub-network set based on the set sub-network grouping rules and the mutual impedance modulus of any two bus nodes in the new energy multi-station short-circuit ratio unqualified node set and the set modulus threshold;

[0021] a third set module, for any two bus nodes in each sub-network set, calculating the shortest path between the two bus nodes based on the grid branch impedance between the two bus nodes, and determining a candidate branch set of the grid based on the number of occurrences of the branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation component data model;

[0022] a fourth set module, configured to generate a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set;

[0023] A second calculation module is configured to calculate the corresponding short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes included in each candidate operating mode in the set of candidate operating modes based on the short-circuit ratio calculation formula;

[0024] The result output module is used to determine the validity result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes contained in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generate a grid optimization adjustment strategy set based on the validity result, wherein the validity result includes a valid operating mode and an invalid operating mode.

[0025] According to yet another aspect of the present invention, the present invention provides a computer-readable storage medium, 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.

[0026] 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 for reading the executable instructions from the memory and executing the instructions to implement the method described in any one of the above aspects of the present invention.

[0027] The present invention provides a grid optimization and adjustment method and device for improving the short-circuit ratio of multiple renewable energy stations. The method comprises the following steps: constructing a digital model of a power grid simulation including multiple renewable energy stations, and calculating the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio of the bus nodes of each renewable energy station according to the operating parameters of the bus nodes under the basic power grid operating mode based on the short-circuit ratio calculation formula; identifying unqualified nodes by the short-circuit ratio, dividing the nodes into sub-networks, identifying the shortest paths, and determining a set of candidate branches; generating a set of candidate operating modes according to the basic power grid operating mode and the branches in the set of candidate branches; determining the effectiveness of each candidate operating mode according to the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with unqualified short-circuit ratios of the renewable energy multi-stations contained in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generating a set of grid optimization and adjustment strategies according to the effectiveness results. The method and device identify unqualified bus nodes under the basic operation mode of the power grid, perform sub-network division and shortest path identification, generate candidate operation modes, and then compare the short-circuit capacity and equivalent capacity of the unqualified bus nodes under the candidate operation modes with the change values ​​of the short-circuit capacity and equivalent capacity of the corresponding unqualified bus nodes under the basic operation mode, thereby realizing the automatic generation of an effective grid optimization adjustment strategy for improving the short-circuit ratio of multiple new energy stations, providing technical support for the scientific planning of new power systems and the safe and stable operation of new energy stations, and contributing to improving the safe and stable operation level of the power grid and the large-scale safe access level of new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0029] Figure 1 Flowchart of a grid optimization and adjustment method for improving the short-circuit ratio of multiple new energy stations according to a preferred embodiment of the present invention;

[0030] Figure 2 A schematic structural diagram of a grid optimization and adjustment device for improving the short-circuit ratio of multiple new energy stations according to a preferred embodiment of the present invention;

[0031] Figure 3 Schematic diagram of the structure of an electronic device according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0032] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a thorough and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments shown in the accompanying drawings is not intended to limit the present invention. In the accompanying drawings, identical elements are denoted by the same reference numerals.

[0033] Unless otherwise specified, the terms used herein (including technical terms) have the meanings commonly understood by those skilled in the art. In addition, it is understood that terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0034] Exemplary Methods

[0035] Figure 1 Flowchart of the grid optimization adjustment method for improving the short-circuit ratio of multiple new energy stations according to the preferred embodiment of the present invention. Figure 1 As shown, the flowchart of the grid optimization adjustment method for improving the short-circuit ratio of multiple new energy stations described in this preferred embodiment starts from step 101.

[0036] In step 101, a power grid simulation digital model including multiple new energy stations is constructed, wherein the power grid simulation digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, the power grid flow simulation component data model constitutes a basic power grid operation mode, the power grid flow simulation component data model includes a new energy station model, and the new energy station model includes a new energy power generation unit.

[0037] In this preferred embodiment, the power grid flow simulation component data model includes the following models: ① transmission line model, parameters include resistance, reactance, conductance, and susceptance; ② transformer model, parameters include leakage reactance, transformation ratio, and tap position; ③ generator model, parameters include active output value and reactive output value; ④ load model, parameters include active value and reactive value; ⑤ new energy station model, including new energy power generation unit bus node information (including node name, node type, reference voltage, node location partition, maximum active output of new energy equipment, actual active output of new energy equipment), line information (including line name, line rated current, resistance per unit value, reactance per unit value, ground susceptance, covering the connection lines between each new energy equipment and the collection station), transformer information (including transformer name, rated capacity, leakage reactance, transformer tap position, covering the box transformer and step-up transformer connected to each new energy equipment). The power grid flow simulation component data model used for the new energy multi-station short-circuit ratio calculation constitutes the basic power grid operation mode, marked as S0. Through the data model of the power grid flow simulation component, the system nominal voltage, self-impedance, injected renewable energy apparent power, mutual impedance between bus nodes, conjugate of operating voltage, etc. can be determined through flow calculation.

[0038] The grid stability simulation element data model includes: a generator model, an excitation system model, a stabilizer model, a speed regulator and prime mover model, and a new energy model, wherein the new energy model includes a general model of a fixed-speed wind turbine, a general model of a doubly-fed type wind turbine, a general model of a direct-drive type wind turbine, a photovoltaic power generation model, and an energy storage system model.

[0039] In step 102, based on the short-circuit ratio calculation formula, the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio are calculated according to the operating parameters of the bus node of each new energy station under the basic power grid operation mode, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes.

[0040] Preferably, the short-circuit ratio calculation formula is based on the operation parameters of the busbar node of each new energy station under the basic power grid operation mode to calculate its corresponding short-circuit capacity, equivalent capacity and short-circuit ratio, wherein the short-circuit ratio calculation formula is:

[0041]

[0042] Where, MRSCR i Represents the short-circuit ratio of the busbar node i of the new energy station; represents the system nominal voltage of busbar node i; Represents the conjugate of the actual operating voltage of bus node i and bus node j respectively; 1≤i,j≤N, N is the total number of bus nodes in the power grid, i, j, N are all natural numbers, They represent the actual apparent power of the new energy injected into bus node i and bus node point respectively; represents the complex power conversion factor between busbar node i and busbar node j, represents the self-impedance of busbar node i, represents the mutual impedance between busbar node i and busbar node j, Sk i Represents the short-circuit capacity of busbar node i; Se i Represents the equivalent capacity of bus node i.

[0043] In this preferred embodiment, the calculation formula for calculating the short-circuit ratio of multiple renewable energy stations in the power grid is the same. Therefore, it is only necessary to know the operating parameter values ​​of the power grid in different operating modes to determine the short-circuit capacity, equivalent capacity and short-circuit ratio in the corresponding operating mode based on the short-circuit ratio calculation formula, wherein the operating parameter values ​​of the power grid in different operating modes are obtained by performing flow calculations in the corresponding operating modes.

[0044] In step 103, based on the set unqualified node judgment rules, the unqualified nodes of the new energy multi-station short circuit ratio are determined according to the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and a set of unqualified nodes of the new energy multi-station short circuit ratio is generated.

[0045] Preferably, the unqualified node judgment rule is set based on the short-circuit ratio of the bus node of each new energy station in the basic power grid operation mode to determine the unqualified node of the new energy multi-station short-circuit ratio, and generate a set of unqualified nodes of the new energy multi-station short-circuit ratio, wherein the expression of the unqualified node judgment rule is:

[0046]

[0047] Where, MRSCR Li is the short-circuit ratio when the busbar node i of the new energy station is the low-voltage node of the new energy power generation unit, MRSCR Hi is the short-circuit ratio when the busbar node i of the new energy station is the grid-connected high-voltage node of the new energy station. Th1 and Th2 are the set short-circuit ratio division thresholds. Both Th1 and Th2 are positive numbers, and Th1 < Th2;

[0048] When the short-circuit ratio of bus node i under the basic power grid operation mode meets the unqualified node judgment rule, bus node i is determined to be an unqualified node for the short-circuit ratio of the new energy multi-station;

[0049] Generate the set of new energy multi-station short circuit ratio unqualified nodes B based on the r busbar nodes that meet the unqualified node criteria L , where B L ={B Ln |1≤n≤r}, n and r are both natural numbers.

[0050] In step 104, based on the set sub-network grouping rules, at least one sub-network set is generated according to the mutual impedance modulus values ​​of any two bus nodes in the new energy multi-station short-circuit ratio unqualified node set and the set modulus threshold.

[0051] Preferably, the subnetwork grouping rule based on the setting is to generate at least one subnetwork set according to the mutual impedance modulus of any two bus nodes in the new energy multi-station short-circuit ratio unqualified node set and the set modulus threshold, wherein the subnetwork grouping rule is:

[0052] Z ab ≥Z min

[0053] Where Z ab is the mutual impedance modulus between busbar node a and busbar node b in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, 1≤a,b≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, a, b, r are all natural numbers, Z min The modulus threshold is set, which is a positive number;

[0054] When there are c pairs of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, and the mutual impedance modulus values ​​under the basic power grid operation mode meet the sub-network grouping rules, the c pairs of busbar nodes are exhausted and permuted to generate k sub-network sets, among which the dth sub-network set is marked as D d , D d contains at least one pair of busbar nodes, 1≤d≤k, d and k are both natural numbers.

[0055] In step 105, for any two bus nodes in each sub-network set, the shortest path between the two bus nodes is calculated based on the grid branch impedance between the two bus nodes, and a candidate branch set of the grid is determined based on the number of occurrences of the branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation element data model.

[0056] Preferably, for any two bus nodes in each sub-network set, the shortest path between the two bus nodes is calculated based on the impedance of the power grid branch between the two bus nodes, and a candidate branch set of the power grid is determined based on the number of occurrences of the branches included in the shortest path, including:

[0057] Step 2-1: For the d-th subnetwork set, label it as D d A set of k sub-networks, initialized with d = 1;

[0058] Step 2-2: When the sub-network set D d When there are u busbar nodes in the system, for any two buses, bus node pairs, where u≤r, r is the total number of bus nodes in the set of nodes with unqualified short-circuit ratios at multiple new energy stations, and C represents a combination calculation in mathematics;

[0059] Step 2-3: For sub-network set D d in The shortest connection path between any bus node pairs is obtained by using the Bidirectional Dijkstra algorithm to identify the shortest connection path between any bus node pairs. busbar pairs Group shortest paths, where each group of shortest paths consists of several branches;

[0060] Step 2-4: According to The branch generation subnetwork set D included in the group shortest path d The key branch set L d ;

[0061] Step 2-5: Count the key branch set L d The number of times each branch appears in the set L is calculated, and the branches are arranged from most to least according to the number of times, and the branch with the most appearances is inserted into the candidate branch set L c In; if the critical branch set L d If there are multiple branches that appear the most times, they will be inserted into the candidate branch set L at the same time. C middle;

[0062] Step 2-6: Update d=d+1. If d≤k, go to step 2-2; if d>k, go to step 2-7.

[0063] Step 2-7: Organize and form a candidate branch set L C ={L 1.max L 2.max … L k.max … L (k+x).max}, where x represents the number of branches that need to be added when there are multiple branches with the highest number of occurrences in the critical branch set.

[0064] In this preferred embodiment, for the sub-network set D d in A pair of bus nodes is selected, and the grid branch impedance is used as the distance measure between the bus node pairs. The Bidirectional Dijkstra algorithm is used to identify the shortest communication path between any bus node pairs. The specific implementation method is to take one of the bus nodes in the bus node pair as the starting point and add it to the forward queue, and take the other bus node as the end point and add it to the backward queue. Under the basic grid operation mode, the shortest path between the two bus nodes is obtained by forward and backward search.

[0065] In step 106 , a candidate operating mode set is generated according to the basic grid operating mode and the branches in the candidate branch set.

[0066] Preferably, generating a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set includes:

[0067] Let the basic grid operation mode be S0 and the candidate branch set be L C ={L 1.max L 2.max … L k.max …L (k+x).max},but:

[0068] Remove set L from S0 C For any branch in the in:

[0069]

[0070] In S0, the set L C Amplify any branch in the system once and generate an operation mode set containing expansion measures. in:

[0071]

[0072] Run As Set Find the union and obtain the candidate operation mode set S containing 2(k+x) candidate operation modes C ,in:

[0073]

[0074] Where S f is the f-th candidate operating mode, 1≤f≤2(k+x), and 2(k+x) is the total number of candidate operating modes.

[0075] In step 107, based on the short-circuit ratio calculation formula, the corresponding short-circuit capacity and equivalent capacity are calculated according to the operating parameters of the unqualified bus nodes in the new energy multi-station short-circuit ratio unqualified node set contained in each candidate operating mode in the candidate operating mode set.

[0076] In step 108, the effectiveness result of each candidate operating mode is determined based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes included in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and a grid optimization adjustment strategy set is generated based on the effectiveness result, wherein the effectiveness result includes a valid operating mode and an invalid operating mode.

[0077] Preferably, determining the effectiveness result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with new energy multi-station short-circuit ratios included in each candidate operating mode under the candidate operating mode, and the short-circuit capacity and equivalent capacity under the basic operating mode, and generating a grid optimization adjustment strategy set based on the effectiveness result, includes:

[0078] Step 3-1: For the fth candidate operation mode S f The candidate operation mode set S C , initialize f=1;

[0079] Step 3-2: According to the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The short-circuit capacity and equivalent capacity under the basic operation mode are calculated respectively for the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The calculation formula for the short-circuit capacity change and equivalent capacity change under φ 1 is:

[0080]

[0081] Where, 1≤n≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, Sk fn 、Sk fn , ΔSk fn and ΔSe fn Candidate operating mode S f The nth unqualified busbar node in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S fShort-circuit capacity, equivalent capacity, short-circuit capacity change value and equivalent capacity change value under Sk f0 and Se f0 Candidate operating mode S f The short-circuit capacity and equivalent capacity of the nth unqualified busbar node in the set of unqualified nodes with short-circuit ratios of multiple new energy stations under the basic operation mode;

[0082] Step 3-3: Determine the operating mode S based on the strategy effectiveness criterion f The effectiveness result of the corresponding optimization adjustment strategy, wherein, if the expression of the effectiveness criterion of the strategy is:

[0083] ΔSk fn *Se f0 >ΔSe fn *Sk f0

[0084] When the candidate operating mode S f All unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S f When the short-circuit capacity change value and equivalent capacity change value under the basic operation mode meet the effectiveness criterion of the strategy, the candidate operation mode S is determined. f The validity result is that the operation mode is valid, and the operation mode S f Mark it as an effective grid optimization adjustment strategy and insert it into the effective grid optimization adjustment strategy set S F When the candidate operation mode S f Any unqualified busbar node in the set of unqualified nodes with multiple new energy stations short circuit ratio is selected in the candidate operation mode S f When the short-circuit capacity change value and the equivalent capacity change value under the basic operation mode do not meet the effectiveness criterion of the strategy, determine the candidate operation mode S f The validity result is that the operation mode is invalid, and the candidate operation mode S f Mark as invalid grid optimization adjustment strategy;

[0085] Step 3-4: Let f = f + 1. If f ≤ 2(k + x), go to step 3-2. If f > 2(k + x), go to step 3-5.

[0086] Step 3-5: Gather and generate a set of effective grid optimization adjustment strategies S F .

[0087] The grid optimization and adjustment method for improving the short-circuit ratio of multiple new energy stations described in this preferred embodiment constructs a grid simulation digital model including multiple new energy stations, and calculates the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio of the bus node of each new energy station according to the operating parameters of the bus node under the basic grid operation mode based on the short-circuit ratio calculation formula; identifies unqualified nodes through the short-circuit ratio, divides them into sub-networks, identifies the shortest paths, and determines a set of candidate branches; generates a set of candidate operation modes according to the basic grid operation mode and the branches in the candidate branch set; determines the effectiveness results of each candidate operation mode according to the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with unqualified short-circuit ratios of the new energy multi-stations contained in each candidate operation mode under the candidate operation mode, as well as the short-circuit capacity and equivalent capacity under the basic operation mode, and generates a set of grid optimization adjustment strategies according to the effectiveness results. The method described realizes the automatic generation of effective grid optimization and adjustment strategies for improving the short-circuit ratio of multiple renewable energy stations, provides technical support for the scientific planning of new power systems and the safe and stable operation of renewable energy stations, and is conducive to improving the safe and stable operation level of the power grid and the large-scale safe access level of renewable energy.

[0088] Exemplary devices

[0089] Figure 2 This is a schematic diagram of the structure of a grid optimization and adjustment device for improving the short-circuit ratio of multiple new energy stations according to a preferred embodiment of the present invention. Figure 2 As shown, the grid optimization and adjustment device 200 for improving the short-circuit ratio of multiple new energy stations described in this preferred embodiment includes:

[0090] Model construction module 201 is used to construct a digital model of power grid simulation including multiple renewable energy stations, wherein the digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, the power grid flow simulation component data model forming a basic power grid operation mode, the power grid flow simulation component data model including a renewable energy station model, and the renewable energy station model including a renewable energy power generation unit;

[0091] A first calculation module 202 is configured to calculate the corresponding short-circuit capacity, equivalent capacity, and short-circuit ratio of the bus node of each new energy station according to the operating parameters of the bus node under the basic power grid operation mode based on the short-circuit ratio calculation formula, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes;

[0092] The first set module 203 is configured to determine the unqualified nodes of the new energy multi-station short circuit ratio based on the set unqualified node judgment rules and the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and generate a set of unqualified nodes of the new energy multi-station short circuit ratio;

[0093] The second set module 204 is configured to generate at least one sub-network set based on the set sub-network grouping rules and the mutual impedance modulus values ​​of any two bus nodes in the new energy multi-station short circuit ratio unqualified node set and the set modulus threshold;

[0094] The third set module 205 calculates, for any two bus nodes in each sub-network set, a shortest path between the two bus nodes based on the grid branch impedance between the two bus nodes, and determines a candidate branch set of the grid based on the number of occurrences of branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation component data model;

[0095] A fourth set module 206 is configured to generate a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set;

[0096] A second calculation module 207 is configured to calculate the corresponding short-circuit capacity and equivalent capacity of each unqualified bus node in the set of unqualified short-circuit ratio nodes of each candidate operating mode in the set of candidate operating modes based on the short-circuit ratio calculation formula;

[0097] The result output module 208 is used to determine the effectiveness result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with new energy multi-station short-circuit ratios included in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generate a grid optimization adjustment strategy set based on the effectiveness result, wherein the effectiveness result includes a valid operating mode and an invalid operating mode.

[0098] Preferably, the first calculation module 202 calculates the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio based on the short-circuit ratio calculation formula according to the operating parameters of the bus node of each new energy station under the basic power grid operation mode, wherein the short-circuit ratio calculation formula is:

[0099]

[0100] Where, MRSCR i Represents the short-circuit ratio of the busbar node i of the new energy station; represents the system nominal voltage of busbar node i; Represents the conjugate of the actual operating voltage of bus node i and bus node j respectively; 1≤i,j≤N, N is the total number of bus nodes in the power grid, i, j, N are all natural numbers, They represent the actual apparent power of the new energy injected into bus node i and bus node point respectively; represents the complex power conversion factor between busbar node i and busbar node j, represents the self-impedance of busbar node i, represents the mutual impedance between busbar node i and busbar node j, Sk i Represents the short-circuit capacity of busbar node i; Se i Represents the equivalent capacity of bus node i.

[0101] Preferably, the first set module 203 determines the unqualified nodes of the new energy multi-station short circuit ratio according to the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode based on the set unqualified node judgment rule, and generates a set of unqualified nodes of the new energy multi-station short circuit ratio, wherein the expression of the unqualified node judgment rule is:

[0102]

[0103] Where, MRSCR Li is the short-circuit ratio when the busbar node i of the new energy station is the low-voltage node of the new energy power generation unit, MRSCR Hi is the short-circuit ratio when the busbar node i of the new energy station is the grid-connected high-voltage node of the new energy station. Th1 and Th2 are the set short-circuit ratio division thresholds. Both Th1 and Th2 are positive numbers, and Th1 < Th2;

[0104] When the short-circuit ratio of bus node i under the basic power grid operation mode meets the unqualified node judgment rule, bus node i is determined to be an unqualified node for the short-circuit ratio of the new energy multi-station;

[0105] Generate the set of new energy multi-station short circuit ratio unqualified nodes B based on the r busbar nodes that meet the unqualified node criteria L , where B L ={B Ln |1≤n≤r}, n and r are both natural numbers.

[0106] Preferably, the second set module 204 generates at least one sub-network set based on the set sub-network grouping rule and the mutual impedance modulus of any two bus nodes in the new energy multi-station short-circuit ratio unqualified node set and the set modulus threshold, wherein the sub-network grouping rule is:

[0107] Z ab ≥Z min

[0108] Where Z ab is the mutual impedance modulus between busbar node a and busbar node b in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, 1≤a,b≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, a, b, r are all natural numbers, Z min The modulus threshold is set, which is a positive number;

[0109] When there are c pairs of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, and the mutual impedance modulus values ​​under the basic power grid operation mode meet the sub-network grouping rules, the c pairs of busbar nodes are exhausted and permuted to generate k sub-network sets, among which the dth sub-network set is marked as D d , D d contains at least one pair of busbar nodes, 1≤d≤k, d and k are both natural numbers.

[0110] Preferably, the third set module 205 calculates the shortest path between any two bus nodes in each sub-network set based on the impedance of the power grid branch between the two bus nodes, and determines a candidate branch set of the power grid based on the number of occurrences of the branches included in the shortest path, including:

[0111] Step 2-1: For the d-th subnetwork set, label it as D d A set of k sub-networks, initialized with d = 1;

[0112] Step 2-2: When the sub-network set D d When there are u busbar nodes in the system, for any two buses, bus node pairs, where u≤r, r is the total number of bus nodes in the set of nodes with unqualified short-circuit ratios at multiple new energy stations, and C represents a combination calculation in mathematics;

[0113] Step 2-3: For sub-network set D d in The shortest connection path between any bus node pairs is obtained by using the Bidirectional Dijkstra algorithm to identify the shortest connection path between any bus node pairs. busbar pairs Group shortest paths, where each group of shortest paths consists of several branches;

[0114] Step 2-4: According to The branch generation subnetwork set D included in the group shortest path d The key branch set L d ;

[0115] Step 2-5: Count the key branch set L d The number of times each branch appears in the set L is calculated, and the branches are arranged from most to least according to the number of times, and the branch with the most appearances is inserted into the candidate branch set L c In; if the critical branch set L d If there are multiple branches that appear the most times, they will be inserted into the candidate branch set L at the same time. C middle;

[0116] Step 2-6: Update d=d+1. If d≤k, go to step 2-2; if d>k, go to step 2-7.

[0117] Step 2-7: Organize and form a candidate branch set L C ={L 1.max L 2.max … L k.max … L (k+x).max}, where x represents the number of branches that need to be added when there are multiple branches with the highest number of occurrences in the critical branch set.

[0118] Preferably, the fourth set module 206 generates a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set, including:

[0119] Let the basic grid operation mode be S0 and the candidate branch set be L C ={L 1.max L 2.max … L k.max …L (k+x).max},but:

[0120] Remove set L from S0 C For any branch in the in:

[0121]

[0122] In S0, the set L C Amplify any branch in the system once and generate an operation mode set containing expansion measures. in:

[0123]

[0124] Run As Set Find the union and obtain the candidate operation mode set S containing 2(k+x) candidate operation modes C ,in:

[0125]

[0126] Where S f is the f-th candidate operating mode, 1≤f≤2(k+x), and 2(k+x) is the total number of candidate operating modes.

[0127] Preferably, the result output module 208 determines the effectiveness result of each candidate operation mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified short-circuit ratio nodes of new energy multi-stations included in each candidate operation mode under the candidate operation mode, as well as the short-circuit capacity and equivalent capacity under the basic operation mode, and generates a grid optimization adjustment strategy set based on the effectiveness result, including:

[0128] Step 3-1: For the fth candidate operation mode S f The candidate operation mode set S C , initialize f=1;

[0129] Step 3-2: According to the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The short-circuit capacity and equivalent capacity under the basic operation mode are calculated respectively for the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The calculation formula for the short-circuit capacity change and equivalent capacity change under φ 1 is:

[0130]

[0131] Where, 1≤n≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, Sk fn 、Se fn , ΔSk fn and ΔSe fn Candidate operating mode S f The nth unqualified busbar node in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S f Short-circuit capacity, equivalent capacity, short-circuit capacity change value and equivalent capacity change value under Sk f0 and Se f0 Candidate operating mode S f The short-circuit capacity and equivalent capacity of the nth unqualified busbar node in the set of unqualified nodes with short-circuit ratios of multiple new energy stations under the basic operation mode;

[0132] Step 3-3: Determine the operating mode S based on the strategy effectiveness criterion fThe effectiveness result of the corresponding optimization adjustment strategy, wherein, if the expression of the effectiveness criterion of the strategy is:

[0133] ΔSk fn *Se f0 >ΔSe fn *Sk f0

[0134] When the candidate operating mode S f All unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S f When the short-circuit capacity change value and equivalent capacity change value under the basic operation mode meet the effectiveness criterion of the strategy, the candidate operation mode S is determined. f The validity result is that the operation mode is valid, and the operation mode S f Mark it as an effective grid optimization adjustment strategy and insert it into the effective grid optimization adjustment strategy set S F When the candidate operation mode S f Any unqualified busbar node in the set of unqualified nodes with multiple new energy stations short circuit ratio is selected in the candidate operation mode S f When the short-circuit capacity change value and the equivalent capacity change value under the basic operation mode do not meet the effectiveness criterion of the strategy, determine the candidate operation mode S f The validity result is that the operation mode is invalid, and the candidate operation mode S f Mark as invalid grid optimization adjustment strategy;

[0135] Step 3-4: Let f = f + 1. If f ≤ 2(k + x), go to step 3-2. If f > 2(k + x), go to step 3-5.

[0136] Step 3-5: Gather and generate a set of effective grid optimization adjustment strategies S F .

[0137] The grid optimization and adjustment device for improving the short-circuit ratio of multiple renewable energy stations described in this preferred embodiment constructs a digital model of a power grid simulation including multiple renewable energy stations, calculates the short-circuit ratio, identifies unqualified nodes, divides sub-networks, generates a set of candidate operating modes, and compares the short-circuit capacity change values ​​and equivalent capacity change values ​​under the candidate operating modes and the basic power grid operating mode to generate a set of grid optimization and adjustment strategies. The steps are the same as those taken in the grid optimization and adjustment method for improving the short-circuit ratio of multiple renewable energy stations described in the present invention, and the technical effects achieved are also the same, so they will not be repeated here.

[0138] Exemplary electronic devices

[0139] Figure 3 1 is a schematic diagram of the structure of an electronic device according to a preferred embodiment of the present invention. The electronic device can be either or both of the first device and the second device, or a standalone device independent of them, and the standalone device can communicate with the first device and the second device to receive collected input signals from them. Figure 3 FIG2 is a block diagram of an electronic device according to an embodiment of the present disclosure. Figure 3 As shown, the electronic device includes one or more processors 301 and a memory 302 .

[0140] The processor 301 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.

[0141] The memory 302 may include one or more computer program products, and the computer program products may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include 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 301 may run the program instructions to implement the energy consumption anomaly diagnosis method based on the enterprise energy consumption space of the various embodiments disclosed above and / or other desired functions. In one example, the electronic device may further include: an input device 303 and an output device 304, and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0142] In addition, the input device 303 may also include, for example, a keyboard, a mouse, and the like.

[0143] The output device 304 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.

[0144] Of course, to simplify, Figure 3 Only some of the components related to the present disclosure 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 scenarios.

[0145] Exemplary computer program products and computer-readable storage media

[0146] In addition to the above-mentioned methods and devices, an embodiment of the present disclosure 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 grid optimization adjustment method for improving the short-circuit ratio of multiple new energy stations according to various embodiments of the present disclosure described in the above "Exemplary Method" section of this specification.

[0147] The computer program product may be written in any combination of one or more programming languages ​​to implement the operations of the disclosed embodiments, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may 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.

[0148] In addition, an embodiment of the present disclosure may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, enables the processor to execute the steps of the grid optimization and adjustment method for improving the short-circuit ratio of multiple new energy stations according to various embodiments of the present disclosure described in the above "Exemplary Method" section of this specification.

[0149] 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, for example, include but is not limited to a system, device or component of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. 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 thereof.

[0150] The basic principles of the present disclosure have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this disclosure are merely illustrative and not restrictive, and should not be construed as necessarily possessed by each embodiment of the present disclosure. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, rather than as limitations. These details do not limit the present disclosure to necessarily being implemented using these specific details.

[0151] Each embodiment in this specification is described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. References to the same or similar parts between the various embodiments are sufficient. For system embodiments, since they are generally similar to the method embodiments, their description is relatively simple. For relevant parts, references to the description of the method embodiments are sufficient.

[0152] The block diagrams of the devices, devices, equipment, and systems involved in this disclosure 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 will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0153] The methods and apparatus of the present disclosure may be implemented in many ways. For example, the methods and apparatus of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above unless otherwise specified. In addition, in some embodiments, the present disclosure may also be implemented as programs recorded in a recording medium, which include machine-readable instructions for implementing the methods according to the present disclosure. Thus, the present disclosure also covers recording media that store programs for executing the methods according to the present disclosure.

[0154] It should also be noted that, in the apparatus, equipment and method of the present disclosure, 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 disclosure. The above description of the disclosed aspects is provided to enable any technician in this field to make or use the present disclosure. Various modifications to these aspects will be very obvious 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 present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown here, but to the widest range consistent with the principles and novel features disclosed herein.

[0155] The above description has been provided for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure 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, alterations, additions, and sub-combinations thereof.

Claims

1. A grid optimization and adjustment method for improving the short-circuit ratio of multiple renewable energy stations, characterized in that: The method comprises: Step 1-1: constructing a digital model of a power grid simulation including multiple renewable energy stations, wherein the digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, wherein the power grid flow simulation component data model constitutes a basic power grid operation mode, and the power grid flow simulation component data model includes a renewable energy station model, wherein the renewable energy station model includes a renewable energy power generation unit; Step 1-2: Based on the short-circuit ratio calculation formula, the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio are calculated according to the operating parameters of the bus node of each new energy station under the basic power grid operation mode, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes; Steps 1-3: Based on the set unqualified node judgment rules, determine the unqualified nodes of the new energy multi-station short circuit ratio according to the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and generate a set of unqualified nodes of the new energy multi-station short circuit ratio; Step 1-4: Based on the set sub-network grouping rules, at least one sub-network set is generated according to the mutual impedance modulus values ​​of any two bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes and the set modulus threshold; Steps 1-5: For any two bus nodes in each subnetwork set, the shortest path between the two bus nodes is calculated based on the grid branch impedance between the two bus nodes, and a candidate branch set of the grid is determined based on the number of occurrences of the branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation component data model; Step 1-6, generating a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set; Step 1-7, based on the short-circuit ratio calculation formula, calculate the corresponding short-circuit capacity and equivalent capacity according to the operating parameters of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes included in each candidate operating mode in the candidate operating mode set; Steps 1-8 determine the effectiveness result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with new energy multi-station short-circuit ratios contained in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generate a grid optimization adjustment strategy set based on the effectiveness results, wherein the effectiveness results include valid operating modes and invalid operating modes.

2. The method according to claim 1, characterized in that Based on the short-circuit ratio calculation formula, the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio are calculated according to the operating parameters of the bus node of each new energy station under the basic power grid operation mode, wherein the short-circuit ratio calculation formula is: Where, MRSCR i Represents the short-circuit ratio of the busbar node i of the new energy station; represents the system nominal voltage of busbar node i; Represents the conjugate of the actual operating voltage of bus node i and bus node j respectively; 1≤i,j≤N, N is the total number of bus nodes in the power grid, i, j, N are all natural numbers, They represent the actual apparent power of the new energy injected into bus node i and bus node point respectively; represents the complex power conversion factor between busbar node i and busbar node j, represents the self-impedance of busbar node i, represents the mutual impedance between busbar node i and busbar node j, Sk i Represents the short-circuit capacity of busbar node i; Se i Represents the equivalent capacity of bus node i.

3. The method according to claim 1, characterized in that Based on the set unqualified node judgment rule, the unqualified nodes of the new energy multi-station short circuit ratio are determined according to the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and a set of unqualified nodes of the new energy multi-station short circuit ratio is generated, wherein the expression of the unqualified node judgment rule is: Where, MRSCR Li is the short-circuit ratio when the busbar node i of the new energy station is the low-voltage node of the new energy power generation unit, MRSCR Hi is the short-circuit ratio when the busbar node i of the new energy station is the grid-connected high-voltage node of the new energy station. Th1 and Th2 are the set short-circuit ratio division thresholds. Both Th1 and Th2 are positive numbers, and Th1 < Th2; When the short-circuit ratio of bus node i under the basic power grid operation mode meets the unqualified node judgment rule, bus node i is determined to be an unqualified node for the short-circuit ratio of the new energy multi-station; Generate the set of new energy multi-station short circuit ratio unqualified nodes B based on the r busbar nodes that meet the unqualified node criteria L , where B L ={B Ln |1≤n≤r}, n and r are both natural numbers.

4. The method according to claim 1, wherein The subnetwork grouping rule based on the setting is to generate at least one subnetwork set according to the mutual impedance modulus of any two bus nodes in the new energy multi-station short circuit ratio unqualified node set and the set modulus threshold, wherein the subnetwork grouping rule is: WITH ab ≥Z min Where Z ab is the mutual impedance modulus between busbar node a and busbar node b in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, 1≤a,b≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratio of new energy multi-stations, a, b, r are all natural numbers, Z min The modulus threshold is set, which is a positive number; When there are c pairs of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, and the mutual impedance modulus values ​​under the basic power grid operation mode meet the sub-network grouping rules, the c pairs of busbar nodes are exhausted and permuted to generate k sub-network sets, among which the dth sub-network set is marked as D d , D d contains at least one pair of busbar nodes, 1≤d≤k, d and k are both natural numbers.

5. The method according to claim 1, wherein The method of calculating the shortest path between any two bus nodes in each sub-network set according to the impedance of the power grid branch between the two bus nodes, and determining a candidate branch set of the power grid according to the number of occurrences of the branches included in the shortest path, includes: Step 2-1: For the d-th subnetwork set, label it as D d A set of k sub-networks, initialized with d = 1; Step 2-2: When the sub-network set D d When there are u busbar nodes in the system, for any two buses, bus node pairs, where u≤r, r is the total number of bus nodes in the set of nodes with unqualified short-circuit ratios at multiple new energy stations, and C represents a combination calculation in mathematics; Step 2-3: For sub-network set D d in The shortest connection path between any bus node pairs is obtained by using the Bidirectional Dijkstra algorithm to identify the shortest connection path between any bus node pairs. busbar pairs Group shortest paths, where each group of shortest paths consists of several branches; Step 2-4: According to The branch generation subnetwork set D included in the group shortest path d The key branch set L d ; Step 2-5: Count the key branch set L d The number of times each branch appears in the set L is calculated, and the branches are arranged from most to least according to the number of times, and the branch with the most appearances is inserted into the candidate branch set L c In; if the critical branch set L d If there are multiple branches that appear the most times, they will be inserted into the candidate branch set L at the same time. C middle; Step 2-6: Update d=d+1. If d≤k, go to step 2-2; if d>k, go to step 2-7. Step 2-7: Organize and form a candidate branch set L C ={L 1.max L 2.max … L k.max … L (k+x).max }, where x represents the number of branches that need to be added when there are multiple branches with the highest number of occurrences in the critical branch set.

6. The method according to claim 1, characterized in that Generating a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set includes: Let the basic grid operation mode be S0 and the candidate branch set be L C ={L 1.max L 2.max … L k.max … L (k+x).max },but: Remove set L from S0 C For any branch in the in: In S0, the set L C Amplify any branch in the system once and generate an operation mode set containing expansion measures. in: Run As Set and Find the union and obtain the candidate operation mode set S containing 2(k+x) candidate operation modes C ,in: Where S f is the f-th candidate operating mode, 1≤f≤2(k+x), and 2(k+x) is the total number of candidate operating modes.

7. The method according to claim 1, characterized in that The determining of the effectiveness result of each candidate operation mode according to the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of unqualified nodes with short-circuit ratios of new energy multi-stations included in each candidate operation mode under the candidate operation mode, and the short-circuit capacity and equivalent capacity under the basic operation mode, and generating a grid optimization adjustment strategy set according to the effectiveness result, includes: Step 3-1: For the fth candidate operation mode S f The candidate operation mode set S C , initialize f=1; Step 3-2: According to the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The short-circuit capacity and equivalent capacity under the basic operation mode are calculated respectively for the candidate operation mode S f The unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations are included in the candidate operation mode S f The calculation formula for the short-circuit capacity change and equivalent capacity change under φ 1 is: Where, 1≤n≤r, r is the total number of busbar nodes in the set of nodes with unqualified short-circuit ratios of new energy multi-stations, Sk fn 、Sk fn , ΔSk fn and ΔSe fn Candidate operating mode S f The nth unqualified busbar node in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S f Short-circuit capacity, equivalent capacity, short-circuit capacity change value and equivalent capacity change value under Sk f0 and Se f0 Candidate operating mode S f The short-circuit capacity and equivalent capacity of the nth unqualified busbar node in the set of unqualified nodes with short-circuit ratios of multiple new energy stations under the basic operation mode; Step 3-3: Determine the operating mode S based on the strategy effectiveness criterion f The effectiveness result of the corresponding optimization adjustment strategy, wherein, if the expression of the effectiveness criterion of the strategy is: ΔSk fn *Se f0 >ΔSe fn *Sk f0 When the candidate operating mode S f All unqualified busbar nodes in the set of unqualified nodes with short-circuit ratio of new energy multi-stations included in the candidate operation mode S f When the short-circuit capacity change value and equivalent capacity change value under the basic operation mode meet the effectiveness criterion of the strategy, the candidate operation mode S is determined. f The validity result is that the operation mode is valid, and the operation mode S f Mark it as an effective grid optimization adjustment strategy and insert it into the effective grid optimization adjustment strategy set S F When the candidate operation mode S f Any unqualified busbar node in the set of unqualified nodes with multiple new energy stations short circuit ratio is selected in the candidate operation mode S f When the short-circuit capacity change value and the equivalent capacity change value under the basic operation mode do not meet the effectiveness criterion of the strategy, determine the candidate operation mode S f The validity result is that the operation mode is invalid, and the candidate operation mode S f Mark as invalid grid optimization adjustment strategy; Step 3-4: Let f = f + 1. If f ≤ 2(k + x), go to step 3-2. If f > 2(k + x), go to step 3-5. Step 3-5: Gather and generate a set of effective grid optimization adjustment strategies S F .

8. A grid optimization and adjustment device for improving the short-circuit ratio of multiple renewable energy stations, characterized in that: The device comprises: A model construction module, configured to construct a digital model of a power grid simulation including multiple renewable energy stations, wherein the digital model includes a power grid flow simulation component data model and a power grid stability simulation component data model, the power grid flow simulation component data model constituting a basic power grid operation mode, the power grid flow simulation component data model including a renewable energy station model, and the renewable energy station model including a renewable energy power generation unit; A first calculation module is used to calculate the corresponding short-circuit capacity, equivalent capacity and short-circuit ratio of the bus node of each new energy station based on the short-circuit ratio calculation formula and the operating parameters of the bus node under the basic power grid operation mode, wherein the bus node of each new energy station includes the low-voltage node of the new energy power generation unit and the grid-connected high-voltage node of each new energy station, and the operating parameters include the system nominal voltage of the bus node, the conjugate of the actual operating voltage, the apparent power of the new energy injected into the power grid, and the self-impedance and the mutual impedance with other bus nodes; The first set module is used to determine the unqualified nodes of the new energy multi-station short circuit ratio based on the set unqualified node judgment rules and the short circuit ratio of the bus node of each new energy station under the basic power grid operation mode, and generate a set of unqualified nodes of the new energy multi-station short circuit ratio; The second set module is used to generate at least one sub-network set based on the set sub-network grouping rules and the mutual impedance modulus of any two bus nodes in the new energy multi-station short-circuit ratio unqualified node set and the set modulus threshold; a third set module, for any two bus nodes in each sub-network set, calculating the shortest path between the two bus nodes based on the grid branch impedance between the two bus nodes, and determining a candidate branch set of the grid based on the number of occurrences of the branches included in the shortest path, wherein the grid branch impedance includes the transmission line reactance and the transformer leakage reactance in the grid power flow simulation component data model; a fourth set module, configured to generate a candidate operating mode set according to the basic power grid operating mode and the branches in the candidate branch set; A second calculation module is configured to calculate the corresponding short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes included in each candidate operating mode in the set of candidate operating modes based on the short-circuit ratio calculation formula; The result output module is used to determine the validity result of each candidate operating mode based on the short-circuit capacity and equivalent capacity of the unqualified bus nodes in the set of new energy multi-station short-circuit ratio unqualified nodes contained in each candidate operating mode under the candidate operating mode, as well as the short-circuit capacity and equivalent capacity under the basic operating mode, and generate a grid optimization adjustment strategy set based on the validity result, wherein the validity result includes a valid operating mode and an invalid operating mode.

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 configured to read the executable instructions from the memory and execute the instructions to implement the method according to any one of claims 1 to 7.

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