Regional power grid standard example construction and evaluation method, device, equipment and medium

Abstract

The invention discloses a regional power grid standard example construction and evaluation method, device and equipment and a medium, which are used for solving the technical problems of incomplete consideration, low applicability and lack of effective example evaluation means of a power grid standard example adopted for an isolated network scene at present. The method comprises the following steps: acquiring a grid topological structure of a regional power grid, and determining at least one isolated grid and an isolated grid type of each isolated grid according to the grid topological structure; performing statistics on power grid parameter information of all isolated grid types included in the regional power grid, and constructing a power grid standard example of the regional power grid according to the power grid parameter information in combination with the topological structure constraint condition; and performing multi-index evaluation on the power grid standard example, and outputting an example evaluation result. By adopting the method provided by the invention, the aims of forming a more comprehensive and higher-adaptability standardized power grid example and quantitatively evaluating the provided standard example can be achieved.

Description

Technical Field

[0001] This invention relates to the field of new power system technology, and in particular to a method, apparatus, equipment and medium for constructing and evaluating standard calculation examples for regional power grids. Background Technology

[0002] In recent years, with the construction of new power systems, a large number of new energy generating units and power plants have connected to the grid via substations at the end of the power grid. The voltage level at the grid connection point is typically 220kV and below. The grid structure is radial or chain-type, with weak connections to the main grid. If a fault trips in the tie line of a radial or chain-type power supply structure, the system strength of the power supply area at the end of the grid (hereinafter referred to as the regional power grid) will further decrease. When the transmission power of the tie line is large, significant power imbalance events will occur in the power supply area at the end. The regional power grid will also experience stability problems such as frequency instability and voltage instability. Unordered tripping of generating units and loads will ultimately trigger a cascading tripping incident leading to a complete blackout of the regional power grid.

[0003] The primary application scenario of this invention is the research on the safe and stable operation control of regional power grids. When power lines and transformers connecting this region to the main grid trip, they are disconnected from the main grid's system support. This leads to a decrease in system strength, and the power plants and loads within the regional power grid form an independent power generation and consumption system. Conventional methods are insufficient to ensure stable operation in this region. Therefore, it is necessary to construct scientific standard calculation examples for studying the safe and stable characteristics and control measures of the end-point power supply area.

[0004] Currently, publicly available standard power grid calculation examples include the IEEE 39-node model. These standard calculation examples have the following problems: (1) Scientific research units can directly obtain these standard calculation examples, but they do not master the design methods of these standard calculation examples. As a result, they cannot apply the knowledge to propose standard calculation examples for specific problems. They have results but no process, and their applicability is not high. (2) The currently available standard calculation examples cannot well reflect the safe and stable operation characteristics of power grids in areas with a high proportion of new energy penetration, and the considerations are not comprehensive enough. (3) For the proposed standard calculation examples, there is a lack of a quantitative evaluation method to scientifically and effectively evaluate the standard calculation examples, which makes it unknown whether the standard calculation examples can reflect the actual operating characteristics of the power grid. Summary of the Invention

[0005] This invention provides a method, apparatus, equipment, and medium for constructing and evaluating standard calculation cases for regional power grids, which solves or partially solves the technical problems of current standard calculation cases for isolated grid scenarios being insufficiently comprehensive, having low applicability, and lacking effective calculation case evaluation methods.

[0006] This invention provides a method for constructing and evaluating standard calculation examples for regional power grids, the method comprising:

[0007] Obtain the grid topology of the regional power grid, and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology;

[0008] The power grid parameters of the region's power grid, including all islanded grid types, are statistically analyzed. Based on these power grid parameters and topology constraints, a standard power grid example for the region's power grid is constructed.

[0009] The power grid standard case is evaluated using multiple indicators, and the case evaluation results are output.

[0010] Optionally, determining at least one isolated network and the isolated network type of each isolated network based on the network topology includes:

[0011] Based on the aforementioned network topology, at least one isolated network caused by a single fault event was identified through line troubleshooting.

[0012] Based on the cause of the formation of isolated networks, the isolated network type of each isolated network is determined; the isolated network type is isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network, or isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network, or isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks.

[0013] Optionally, the statistics on the regional power grid include power grid parameter information for all islanded grid types, including:

[0014] The maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level of all isolated grids in the regional power grid are statistically analyzed and used as the power grid parameter information for the regional power grid including all isolated grid types.

[0015] Optionally, the power grid parameter information includes the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level for all isolated grids in the regional power grid; the step of constructing a standard power grid example for the regional power grid based on the power grid parameter information and topology constraints includes:

[0016] Based on the maximum number of 110kV substations and the average number of 110kV substations, and combined with the first quantity coefficient, a 110kV substation quantity model is constructed.

[0017] Based on the maximum number of 220kV substations and the average number of 220kV substations, and combined with the second quantity coefficient, a 220kV substation quantity model is constructed.

[0018] Based on the maximum installed capacity and the average installed capacity, and combined with the power supply installed capacity coefficient, a model of total power supply installed capacity is constructed.

[0019] Based on the maximum load level and the average installed capacity, and combined with the total load factor, a total load model is constructed;

[0020] Construct topology constraints that consider all islanded network types in the regional power grid;

[0021] Based on the 110kV substation quantity model, the 220kV substation quantity model, the total installed power capacity model, the total load model, and the topology constraints, a standard power grid example for the regional power grid is constructed.

[0022] Optionally, the topology constraints indicate that the constructed standard power grid example must simultaneously satisfy the following constraints:

[0023] Constraint 1: The standard power grid example is a connected network;

[0024] Constraint 2: A single fault event can generate different types of isolated network configurations; the different isolated network types include isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network; isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network; and isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks.

[0025] Constraint 3: The types of power generation and consumption simultaneously include hydropower, thermal power, photovoltaic power generation, wind power generation, energy storage, and load;

[0026] Constraint 4: The grid voltage level includes both 220kV and 110kV.

[0027] Optionally, the step of performing multi-index evaluation on the power grid standard case and outputting the case evaluation results includes:

[0028] By setting different grid-connected power generation schemes, the operation mode of wind, solar, hydro, thermal and storage in the standard grid calculation example can be flexibly adjusted;

[0029] By setting different new energy power outputs and synchronous generator outputs, the maximum power output penetration rate of new energy in the power grid standard calculation example is controlled within a preset penetration rate range.

[0030] By combining the error comparison analysis of analytical calculation and simulation calculation, the frequency response characteristics and the short-circuit ratio of multiple power stations at new energy grid connection points are evaluated respectively.

[0031] The results of the output operation mode adjustment, the maximum output permeability control, the frequency response characteristic evaluation, and the short-circuit ratio evaluation of multiple substations are used as the evaluation results of the standard power grid calculation.

[0032] Optionally, the error comparison analysis combining analytical calculation and simulation calculation, and the evaluation of frequency response characteristics and the evaluation of the short-circuit ratio of multiple power stations at new energy grid connection points, respectively, include:

[0033] Analytical calculations and simulation calculations based on system inertia were performed on the aforementioned standard power grid calculation examples to obtain the first analytical calculation results and the first simulation calculation results.

[0034] Using the maximum frequency deviation, steady-state frequency deviation, and maximum frequency change rate as comparison parameters, the first analytical calculation result is compared with the first simulation calculation result to form a frequency response characteristic evaluation result.

[0035] The standard power grid example was subjected to analytical and simulation calculations based on the short-circuit ratio of multiple power stations at the new energy grid connection point, and the second analytical calculation results and the second simulation calculation results were obtained.

[0036] Using the relative deviation of the short-circuit ratio as a comparison parameter, the second analytical calculation result is compared with the second simulation calculation result to form the short-circuit ratio evaluation result of multiple power stations for new energy grid connection points.

[0037] This invention also provides a device for constructing and evaluating standard calculation examples for regional power grids, comprising:

[0038] An isolated network determination unit is used to obtain the grid topology of a regional power grid and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology.

[0039] The power grid standard case construction unit is used to collect power grid parameter information of all islanded grid types in the regional power grid, and construct the power grid standard case of the regional power grid based on the power grid parameter information and topology constraints.

[0040] The standard case evaluation unit is used to evaluate the power grid standard case using multiple indicators and output the case evaluation results.

[0041] The present invention also provides an electronic device, the device comprising a processor and a memory:

[0042] The memory is used to store program code and transmit the program code to the processor;

[0043] The processor is used to execute the regional power grid standard example construction and evaluation method as described above, according to the instructions in the program code.

[0044] The present invention also provides a computer-readable storage medium for storing program code for executing the regional power grid standard example construction and evaluation method as described in any of the preceding claims.

[0045] As can be seen from the above technical solutions, the present invention has the following advantages:

[0046] This paper presents a method for constructing and evaluating standard calculation examples for regional power grids. First, the grid topology of the regional power grid is obtained, and based on this topology, at least one isolated grid and its type are identified. By proposing a method for determining isolated grids in the regional power grid, a program can be designed to automatically identify weak links in the power supply of the large power grid, demonstrating strong practicality. Next, grid parameter information for all isolated grid types within the regional power grid is statistically analyzed. Based on this grid parameter information and topology constraints, a standard calculation example for the regional power grid is constructed. This approach, on the one hand, considers all isolated grid scenarios across the entire regional power grid, enabling quantitative design of the standard model. On the other hand, by imposing explicit constraints on the grid topology of the standard calculation example, the final constructed standard calculation example is more comprehensive, effective, and applicable to diverse regional power grid structures. Finally, the standard calculation example is evaluated using multiple indicators, and the evaluation results are output. This allows for a comprehensive evaluation of the standard model through quantitative indicators. By employing the method proposed in this invention, a more comprehensive and adaptable standardized power grid calculation example can be formed, and the proposed standard calculation example can be quantitatively evaluated. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 A flowchart illustrating the steps involved in constructing and evaluating a standard calculation example for a regional power grid.

[0049] Figure 2 A schematic diagram of island network type 1, formed by the tripping of a 220kV main transformer to create a 110kV island network;

[0050] Figure 3 A schematic diagram of island network type 2, formed by the tripping of a 220kV line, showing an island network of 220kV mesh network.

[0051] Figure 4 A schematic diagram of island network type 3, which is formed by the tripping of multiple 220kV island networks due to the chain structure of 220kV lines;

[0052] Figure 5 This is a schematic diagram illustrating the comparison parameters in the evaluation of frequency response characteristics.

[0053] Figure 6 This is a simplified schematic diagram of the frequency response model in the analytical calculation method;

[0054] Figure 7 A schematic diagram illustrating the overall process of constructing and evaluating a standard calculation example for a regional power grid.

[0055] Figure 8 This is a schematic diagram of a standard power grid calculation example designed for a specific case.

[0056] Figure 9 This is a schematic diagram comparing the calculation results of the frequency response model and the time-domain simulation in a specific example;

[0057] Figure 10 This is a structural block diagram of a device for constructing and evaluating a standard calculation example for a regional power grid. Detailed Implementation

[0058] This invention provides a method, apparatus, equipment, and medium for constructing and evaluating standard calculation cases for regional power grids, which solves or partially solves the technical problems of current standard calculation cases for isolated grid scenarios being insufficiently comprehensive, having low applicability, and lacking effective calculation case evaluation methods.

[0059] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0060] To enable those skilled in the art to better understand the technical solutions provided in the embodiments of the present invention, some of the technical features involved in the solutions are briefly described first:

[0061] Power Grid Standard Cases: In the context of power grids, power grid standard cases refer to typical examples or benchmark tests used for power system analysis and calculation. These cases can be used to test the performance of various algorithms, models, and tools under different conditions, ensuring the safe and stable operation of the power system.

[0062] As an example, currently published standard calculation examples for power grids include the IEEE 39-node model and other standard calculation examples. These standard calculation examples have the following problems: (1) Scientific research units can directly obtain the standard calculation examples, but they do not master the design methods of the standard calculation examples. As a result, they cannot apply the knowledge to propose standard calculation examples for specific problems. They have results but no process, and their applicability is not high. (2) The currently published standard calculation examples cannot well reflect the safe and stable operation characteristics of power grids in areas with a high proportion of new energy penetration, and the considerations are not comprehensive enough. (3) For the proposed standard calculation examples, there is a lack of a quantitative evaluation method to scientifically and effectively evaluate the standard calculation examples, which makes it unknown whether the standard calculation examples can reflect the actual operating characteristics of the power grid.

[0063] Further analysis reveals two key aspects: First, the power grid's end-point structure exhibits diverse forms, including various topologies, voltage levels, and power source types. Conducting simulations or theoretical analyses for each element in this scenario is time-consuming and labor-intensive, hindering the development of a systematic and theoretical safety and stability control system. Second, information regarding the power grid's specific wiring methods, installed generating capacity, load levels, and critical equipment parameters belongs to the respective asset owners and is not suitable for direct public disclosure. Therefore, it cannot be provided to power research institutions and universities for scientific and technological research. Furthermore, during power grid planning and design studies, the project owners have not yet completed project bidding and construction, making it impossible to provide crucial parameters and control characteristics of electrical equipment, thus hindering the improvement of power grid safety and stability. Additionally, the information on critical equipment parameters and grid structure is overly complex. Scientific classification, refinement, and systematic evaluation of this information are necessary for a fundamental exploration of the power system's safety and stability characteristics.

[0064] Therefore, one of the core inventive points of this invention is to propose a quantitative construction and evaluation method for standard calculation examples of regional power grids, addressing the research needs on the safety and stability characteristics of regional power grids. The first step involves obtaining the grid topology of the regional power grid and, based on this topology, determining at least one isolated grid and the isolated grid type of each isolated grid. By proposing specific methods for determining isolated grids in the regional power grid, a program can be designed to automatically identify weak links in the power supply of the large power grid, demonstrating strong practicality. Furthermore, by summarizing several typical isolated grid formation types, the method offers comprehensiveness and generality. The second step involves statistically analyzing the grid parameter information of the regional power grid, including all isolated grid types, and, based on this information and combined with topological constraints, constructing standard calculation examples of the regional power grid. This, on the one hand, considers all isolated grid scenarios across the entire regional power grid, providing specific calculation methods for the number of power stations, isolated grid generation capacity, and load, thus achieving quantitative design of the standard model. On the other hand, by proposing clear constraints and quantitative technical indicators for the grid topology of the standard calculation examples of the regional power grid, the final constructed standard calculation examples are more comprehensive and effective, and more applicable to the diverse grid structures of regional power grids. The third step involves evaluating the standard power grid simulation case using multiple indicators and outputting the evaluation results. This is achieved by proposing specific applications of various evaluation indicators, particularly for frequency response characteristic evaluation and multi-site short-circuit ratio evaluation. An error comparison analysis based on analytical and simulation calculations is proposed to calculate the relative errors of key technical indicators, thus enabling a comprehensive evaluation of the standard model through quantitative indicators.

[0065] Reference Figure 1 The diagram illustrates a flowchart of the steps involved in constructing and evaluating a regional power grid standard example according to an embodiment of the present invention. Specifically, it may include the following steps:

[0066] Step 101: Obtain the grid topology of the regional power grid, and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology.

[0067] This step primarily involves surveying weak power supply areas at the end of the regional power grid to summarize the topology and parameters of isolated networks. In practical applications, it is necessary to obtain the grid topology of the regional power grid through surveys, and based on the grid topology, determine at least one isolated network and the isolated network type of each isolated network for subsequent construction of standard power grid examples.

[0068] In specific implementation, the process of determining at least one isolated network and the isolated network type of each isolated network according to the network topology mainly includes the following steps S01 to S02:

[0069] Step S01: Based on the network topology, identify at least one isolated network caused by a single fault event through line troubleshooting;

[0070] Firstly, based on the network topology, at least one isolated network caused by a single fault event can be identified through line inspection. This single fault event can mainly include two types of fault scenarios. The first type is a line fault tripping between adjacent 220kV busbars (which can be one or more lines). The second type is a transformer fault tripping between 220kV and 110kV busbars (which can be one or more transformers).

[0071] Specifically, the process for identifying isolated grids (which can also be understood as identifying weak power supply areas at the end of the power grid) through line inspection is as follows: Based on the power grid topology diagram, disconnect all 220kV / 110kV transformers or lines between adjacent 220kV busbars one by one, and check whether the remaining grid topology is still a connected graph. When the remaining grid becomes a disconnected graph (i.e., forming two independent subsystems that are no longer connected to each other), the part not connected to the 500kV main grid is determined to be an isolated grid.

[0072] By proposing specific methods for determining isolated grids in regional power grids, programs can be designed to automatically identify weak links in the power supply of large power grids, which is highly practical.

[0073] Step S02: Determine the type of each isolated network based on the reasons for its formation.

[0074] Next, we can classify isolated networks into different types based on the reasons for their formation.

[0075] For example, such as Figures 2 to 4 In this embodiment of the invention, all isolated network types caused by a single fault event are classified into the following three isolated network types.

[0076] Figure 2 The isolated network type 1 shown is a 220kV main transformer tripping to form a 110kV isolated network.

[0077] Figure 3 The island type 2 shown is a 220kV grid island formed by the tripping of a 220kV line.

[0078] Figure 4 The isolated network type 3 shown is a chain structure where multiple 220kV isolated networks are formed by the tripping of 220kV lines.

[0079] Therefore, when making actual judgments, the type of each isolated network in the regional power grid can be isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network; or isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network; or isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks.

[0080] It should be added that, in combination Figure 4It can be seen that there are multiple isolated network sections in isolated network type 3. When designing the standard case, isolated network section 1, which is closest to the 500kV main grid, will be used as the design reference to cover as many actual isolated network operation scenarios as possible.

[0081] This study summarizes three typical types of isolated networks, demonstrating comprehensiveness and generalization. The limited number of classifications (only three) avoids excessive categorization while maintaining both generality and simplicity.

[0082] Step 102: Collect grid parameter information for all islanded grid types in the regional power grid, and construct a standard grid example for the regional power grid based on the grid parameter information and topology constraints.

[0083] This step mainly involves statistically analyzing the annual load and power generation capacity of the above three types of isolated grids as grid parameter information for the regional power grid. Based on the statistical information and combined with the topology constraints of the design, a standard grid example for the regional power grid is constructed.

[0084] In some embodiments, the statistical regional power grid includes power grid parameter information for all islanded grid types. Specifically, this can be achieved by statistically analyzing the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum (power source) installed capacity, the maximum load level, the average (power source) installed capacity, and the average load level for all islanded grids in the regional power grid. The specific information to be statistically analyzed is shown in Table 1.

[0085] Table 1: Overall Situation of Isolated Grids at the End of Regional Power Grid Supply

[0086]

[0087] As can be seen from Table 1, the power grid parameter information collected in this step mainly includes the maximum number of 110kV substations for all isolated grids in the regional power grid. Maximum number of 220kV substations Average number of 110kV substations Average number of 220kV substations Maximum installed capacity Maximum load level Average installed capacity Average load level .

[0088] Furthermore, based on the power grid parameter information and combined with the topology constraints, the specific implementation process of the regional power grid standard calculation case is constructed, which mainly includes the following steps S11 to S16:

[0089] Step S11: Based on the maximum number of 110kV substations and the average number of 110kV substations, and combined with the first quantity coefficient, construct a 110kV substation quantity model;

[0090] Set the first quantity coefficient Its value is in the interval Between. Therefore, the model for the number of 110kV substations in the standard power grid example is:

[0091]

[0092] Among them, the number of 110kV substations Take a positive integer.

[0093] Step S12: Based on the maximum number of 220kV substations and the average number of 220kV substations, and combined with the second quantity coefficient, construct a 220kV substation quantity model;

[0094] Set the second quantity coefficient Its value is in the interval Between. Therefore, the model for the number of 220kV substations in the standard power grid example is:

[0095]

[0096] Among them, the number of 220kV substations Take a positive integer.

[0097] Step S13: Based on the maximum installed capacity and average installed capacity, and combined with the power supply installation coefficient, construct a model for the total installed power supply capacity;

[0098] Set power supply installation coefficient Its value is in the interval Between. Then the total installed power capacity model for the standard power grid example is:

[0099]

[0100] Step S14: Based on the maximum load level and average installed capacity, and combined with the total load factor, construct the total load model;

[0101] Set the total load factor Its value is in the interval Between. Therefore, the total load model for the standard power grid example is:

[0102]

[0103] Step S15: Construct topology constraints that consider all islanded network types in the regional power grid;

[0104] Step S15 mainly involves designing the network topology of the standard simulation case based on the three types of isolated grids obtained through the above steps. The designed network topology must simultaneously meet the following requirements: the standard grid simulation case must be a connected network; a single fault can generate three types of isolated grid configurations; it must include six types of power generation and consumption: hydropower, thermal power, photovoltaic power, wind power, energy storage, and loads; and the grid voltage levels must include 220kV and 110kV.

[0105] In the specific implementation, the topology constraints mean that the constructed standard power grid example must simultaneously satisfy the following constraints:

[0106] Constraint 1: The standard power grid example is a connected network;

[0107] Constraint 2: A single fault event can generate different types of islanded networks; different islanded network types include islanded network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV islanded network; islanded network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh islanded network; and islanded network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV islanded networks.

[0108] Constraint 3: The types of power generation and consumption simultaneously include hydropower, thermal power, photovoltaic power generation, wind power generation, energy storage, and load;

[0109] Constraint 4: The grid voltage level includes both 220kV and 110kV.

[0110] Step S16: Based on the 110kV substation quantity model, 220kV substation quantity model, total power generation capacity model, total load model, and topology constraints, construct a standard power grid example for the regional power grid.

[0111] This approach, on the one hand, considers all isolated grid scenarios across the regional power grid, providing specific calculation methods for the number of power stations, isolated grid generation capacity, and load, thus enabling the quantitative design of the standard model. On the other hand, this step also proposes four explicit constraints and three quantitative technical indicators (isolated grid type, generation and consumption type, and grid voltage level) for the grid topology of the regional power grid standard example, making the final constructed power grid standard example more comprehensive, effective, and applicable to the diverse grid structures of regional power grids.

[0112] Step 103: Perform multi-index evaluation on the power grid standard case and output the case evaluation results.

[0113] This step mainly considers multiple indicators to evaluate the previously constructed power grid standard case study and obtain the case study evaluation results. Among them, the embodiments of this invention mainly set four types of evaluation indicators: flexible adjustment of wind, solar, hydro, thermal and energy storage operation modes, new energy power generation penetration rate, frequency response characteristics, and short-circuit ratio of multiple new energy power stations.

[0114] In some embodiments, the process of evaluating a standard power grid example using multiple indicators and outputting the evaluation results may mainly include the following steps S21 to S24:

[0115] Step S21: By setting different grid-connected power generation schemes for different units, the operation mode of wind, solar, hydro, thermal and storage in the standard grid calculation example can be flexibly adjusted;

[0116] The first step is to evaluate the flexible adjustment of wind, solar, hydro, thermal, and energy storage operation modes.

[0117] Specifically, by setting different grid-connected power generation schemes for different generating units, there can be independent grid-connected operation modes for hydropower, thermal power, photovoltaic power, wind power, and energy storage, as well as bundled transmission operation modes.

[0118] Step S22: By setting different new energy output and synchronous generator output, the maximum output penetration rate of new energy in the standard grid calculation case is controlled within the preset penetration rate range;

[0119] The second is the evaluation of the penetration rate of new energy power generation.

[0120] Specifically, by setting different output levels for new energy sources and synchronous generators, the maximum penetration rate of new energy output can be controlled between 0% and 80%. The calculation formula is as follows: . and These represent the output from all new energy sources and the output from all generator units, respectively.

[0121] Step S23: Combine the error comparison analysis of analytical calculation and simulation calculation to evaluate the frequency response characteristics and the short-circuit ratio of multiple power stations at the new energy grid connection points;

[0122] Next is the evaluation of frequency response characteristics and the evaluation of the short-circuit ratio of multiple power stations at new energy grid connection points.

[0123] Specifically, for frequency response characteristic evaluation, the analytical calculation method is used as the reference standard. The time-domain simulation calculation results of the power grid standard case are compared with the analytical calculation results, and the maximum frequency deviation is used as the benchmark. steady-state frequency deviation Maximum frequency change rate To compare parameters, a frequency response characteristic evaluation method is developed. The evaluation process for the short-circuit ratio of multiple power plants connected to the grid for new energy sources is similar to that for the frequency response characteristic evaluation, but the evaluation of the short-circuit ratio of multiple power plants connected to the grid for new energy sources uses the relative deviation of the short-circuit ratio as a comparison parameter.

[0124] In a specific implementation, step S23 can mainly include steps S231 to S234:

[0125] Step S231: Perform analytical calculations and simulation calculations based on system inertia on the standard power grid example to obtain the first analytical calculation results and the first simulation calculation results;

[0126] For the analytical calculation of the frequency response characteristics in the standard power grid example, to facilitate understanding, Figure 5 A schematic diagram illustrating the comparison parameters in the frequency response characteristic evaluation is shown. Figure 6 This shows a simplified schematic diagram of the frequency response model in the analytical calculation method.

[0127] in, Figure 5 In time The x-axis represents frequency. The vertical axis is denoted by . The reference frequency or rated frequency indicates the system's stable operating frequency; This indicates the lower limit of the allowable stable frequency deviation. This indicates the upper limit of the allowable steady-state frequency deviation.

[0128] Combination Figure 6 The frequency response model shown has the following system inertia. This calculation considers only the inertia of traditional power sources, excluding the inertia provided by new energy sources and loads. The specific calculation formula is as follows:

[0129]

[0130] in, The per-unit value for the inertia of each traditional generator unit; The rated capacity of each unit; This refers to the maximum power output penetration rate of new energy sources (i.e., the power ratio of new energy generator sets).

[0131] Figure 6 middle, The primary frequency regulation response time constant of the generator set; This refers to the droop coefficient of the hydroelectric generator unit; This refers to the power disturbance in the power grid system, which occurs when a power grid interconnection line trips due to a fault. This refers to the power of the tie line; This refers to the power regulation caused by frequency disturbances in the power grid generators. The Laplace operator is used; considering the impact of load response on frequency, the parameters of the load feedback loop are set. And take typical values It is 1.8.

[0132] For time-domain simulation calculations of standard power grid examples, the standard model is set to trip due to an isolated network section fault, thus forming an isolated network. The frequency response of the isolated network system is then obtained through simulation calculations using common electromechanical transient simulation programs.

[0133] Step S232: Using the maximum frequency deviation, steady-state frequency deviation, and maximum frequency change rate as comparison parameters, compare the first analytical calculation result with the first simulation calculation result to form a frequency response characteristic evaluation result;

[0134] In this step, the time-domain simulation results of the standard power grid example are compared with the results of the analytical calculation method to calculate the maximum frequency deviation. steady-state frequency deviation Maximum frequency change rate The relative errors of the three key parameters. When the absolute value of the relative error is less than 20%, the design requirements for the frequency response characteristics of the standard power grid example are met.

[0135] Step S233: Perform analytical and simulation calculations on the standard power grid example based on the short-circuit ratio of multiple power stations at the new energy grid connection point, and obtain the second analytical calculation results and the second simulation calculation results;

[0136] For evaluating the short-circuit ratio of multiple power stations at new energy grid connection points, the short-circuit ratio of multiple power stations can be calculated using the following formula:

[0137]

[0138] in, This indicates the short-circuit ratio of multiple power stations at new energy grid connection points; This indicates the three-phase short-circuit capacity at the new energy grid connection point; This represents the total rated capacity of all new energy power plants.

[0139] For the analytical calculation of the short-circuit ratio of multiple power plants at the new energy grid connection point in the standard power grid example, the three-phase short-circuit capacity of the grid connection point can first be calculated using the following formula:

[0140]

[0141] in, The rated voltage at the grid connection point; This is the equivalent impedance on the power grid side.

[0142] Next, the total amount of new energy is calculated using the following formula:

[0143]

[0144] Finally, based on the multi-station short-circuit ratio formula... Calculate the short-circuit ratio of multiple power stations at new energy grid connection points .

[0145] For the short-circuit ratio simulation calculation of multiple power plants at the renewable energy grid connection point in the standard power grid example, a detailed electromagnetic transient or electromechanical transient model including the power grid, transformers, lines, and all renewable energy power plants can be established first. A three-phase short-circuit fault is then set at the renewable energy grid connection point to simulate the fault current. Extract the short-circuit current and calculate the three-phase short-circuit capacity at the grid connection point using the following formula:

[0146]

[0147] Then, based on the formula for total new energy... Formula for comparing short circuits at multiple stations Calculate the total amount of new energy separately Short circuit ratio at multiple power stations and new energy grid connection points .

[0148] Step S234: Using the relative deviation of the short-circuit ratio as the comparison parameter, compare the error between the second analytical calculation result and the second simulation calculation result to form the multi-site short-circuit ratio evaluation result of the new energy grid connection point.

[0149] Based on the analytical and simulation calculation methods for the short-circuit ratio of multiple renewable energy grid-connected points introduced in step S233, the short-circuit ratio of all renewable energy grid-connected points in the standard model corresponding to the standard power grid example is calculated one by one, and the relative deviation of the short-circuit ratio of each renewable energy grid-connected point is calculated separately. When the absolute value of the relative error of the short-circuit ratio of multiple renewable energy grid-connected points is less than 20%, the design requirements for the short-circuit ratio of multiple renewable energy grid-connected points in the standard power grid example are met. Specifically, when judging the design requirement threshold, the short-circuit ratio deviation of all renewable energy grid-connected points must be less than 20% simultaneously.

[0150] Step S24: Output the operation mode adjustment results, maximum output penetration rate control results, frequency response characteristic evaluation results, and multi-station short-circuit ratio evaluation results as the example evaluation results of the power grid standard example.

[0151] Finally, the results of operation mode adjustment, maximum output penetration rate control, frequency response characteristic evaluation, and multi-station short-circuit ratio evaluation can be output as the evaluation results of the power grid standard case, thus completing the evaluation of the power grid standard case.

[0152] Therefore, by proposing specific applications of multiple evaluation indicators, especially for frequency response characteristic evaluation and multi-site short-circuit ratio evaluation, an error comparison analysis based on analytical calculation and simulation calculation is proposed to calculate the relative error of key technical indicators and to comprehensively evaluate the standard model through quantitative indicators.

[0153] This invention proposes a method for the quantitative construction and evaluation of standard calculation examples for regional power grids. The first step involves obtaining the grid topology of the regional power grid and, based on this topology, determining at least one isolated grid and the isolated grid type for each isolated grid. By proposing specific methods for determining isolated grids in the regional power grid, a program can be designed to automatically identify weak links in the power supply of the large power grid, demonstrating strong practicality. Furthermore, by summarizing several typical isolated grid formation types, the method offers comprehensiveness and generality. The second step involves statistically analyzing the grid parameter information for all isolated grid types within the regional power grid. Based on this grid parameter information and combined with topological constraints, a standard calculation example for the regional power grid is constructed. This approach, on the one hand, considers all isolated grid scenarios across the entire regional power grid, providing specific calculation methods for the number of power stations, isolated grid generation capacity, and load, thus achieving quantitative design of the standard model. On the other hand, by proposing clear constraints and quantitative technical indicators for the grid topology of the standard calculation example, the final constructed standard calculation example is more comprehensive and effective, and more applicable to the diverse grid structures of regional power grids. The third step involves evaluating the standard calculation example using multiple indicators and outputting the evaluation results. This invention proposes specific applications of multiple evaluation indicators, particularly for frequency response characteristic evaluation and multi-site short-circuit ratio evaluation. It proposes an error comparison analysis based on analytical and simulation calculations to calculate the relative errors of key technical indicators, and achieves a comprehensive evaluation of the standard model through quantitative indicators. By adopting the technical solution proposed in this invention, a more comprehensive and adaptable standardized power grid example can be formed, and the proposed standard example can be quantitatively evaluated.

[0154] For better illustration, refer to Figure 7 This diagram illustrates the overall flow of a method for constructing and evaluating regional power grid standard calculation cases according to an embodiment of the present invention. It should be noted that this embodiment only provides a brief description of the general flow of constructing and evaluating regional power grid standard calculation cases. The specific implementation process of each step can be understood by referring to the relevant content in the foregoing embodiments, and will not be elaborated here. It is understood that the present invention does not impose any limitations on this.

[0155] Step 701: Obtain the grid topology of the regional power grid, and based on the grid topology, determine at least one isolated network and the isolated network type of each isolated network;

[0156] Step 702: Calculate the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level for all isolated grids in the regional power grid.

[0157] Step 703: Based on the maximum number of 110kV substations and the average number of 110kV substations, and combined with the first quantity coefficient, construct a 110kV substation quantity model; based on the maximum number of 220kV substations and the average number of 220kV substations, and combined with the second quantity coefficient, construct a 220kV substation quantity model; based on the maximum and average installed capacity, and combined with the power generation capacity coefficient, construct a total power generation capacity model; based on the maximum load level and the average installed capacity, and combined with the total load coefficient, construct a total load model.

[0158] Step 704: Construct topology constraints that consider all islanded network types in the regional power grid, and build a standard power grid example for the regional power grid based on the 110kV site quantity model, 220kV site quantity model, total power generation capacity model, total load model, and topology constraints.

[0159] Step 705: By setting different grid-connected power generation schemes, the operation mode of wind, solar, hydro, thermal and storage in the standard grid calculation case can be flexibly adjusted; by setting different new energy output and synchronous generator output, the maximum output penetration rate of new energy in the standard grid calculation case can be controlled within the preset penetration rate range; by combining the error comparison analysis of analytical calculation and simulation calculation, the frequency response characteristics and the short-circuit ratio of multiple power stations at the new energy grid connection point are evaluated respectively.

[0160] Step 706: Output the operation mode adjustment results, maximum output penetration rate control results, frequency response characteristic evaluation results, and multi-station short-circuit ratio evaluation results as the example evaluation results of the power grid standard example.

[0161] To enable those skilled in the art to better understand the technical solutions of the present invention, the following specific example is used to illustrate the embodiments of the present invention.

[0162] Based on the standard example construction process provided in the previous embodiments, a specific power grid standard example is designed. Figure 8 As shown. The standard power grid example satisfies the following constraints:

[0163] (1) The standard power grid example is a connected network, where any station has at least one path connecting it to other stations.

[0164] (2) A single fault can generate three types of isolated network configurations. After fault F4 causes the 220kV / 110kV transformer between bus 9 and bus 17 to trip, the remaining 110kV power grid meets the requirements. Figure 2 The isolated network shown is type 1. After fault F3 causes the line between substation 6 and substation 9 to trip, the resulting isolated network conforms to type 1. Figure 3 The isolated network type shown is 2. Substations 1, 2, 6, and 9 form a chain power supply structure. If a fault occurs at the isolated network section closest to the 500kV line, i.e., the 525 / 220 transformer section, F1 trips, which meets the requirements. Figure 4 The isolated network type shown is 3.

[0165] 3) It includes six types of power generation and consumption: hydropower, thermal power, photovoltaic power, wind power, energy storage, and load.

[0166] 4) The power grid voltage levels include 220kV and 110kV.

[0167] The following lists Figure 8 The installed capacity of each power generation unit in the standard power grid calculation example is shown in Table 2.

[0168] Table 2: Capacity of Various Types of Generating Units in Standard Power Grid Calculation Examples

[0169]

[0170] Table 3: Load Capacity of Each Station in Standard Calculation Example (Large-Scale Operation)

[0171]

[0172] "Maximum load mode" refers to the maximum load mode or the maximum load mode of the entire network. In this case, it is assumed that all users in the power grid simultaneously reach their maximum load demand. It is mainly used to verify the power supply capacity of the power grid, equipment capacity, and system stability.

[0173] Evaluation Indicator 1: Flexible adjustment of wind, solar, hydro, thermal, and storage operation modes

[0174] By setting up different grid-connected power generation schemes for power generation units 3, 4, 5, 7, and 8, there are independent grid-connected operation modes for hydropower, thermal power, photovoltaic power, wind power, and energy storage, as well as bundled transmission operation modes.

[0175] As shown in Table 4, the last column indicates the start-up mode. Under the operation mode where only photovoltaic power stations, wind power stations, and hydropower stations are running, a power generation mode is formed that combines photovoltaic, wind, and hydropower and transmits the power through substation 6.

[0176] Table 4: Load Capacity of Each Station in Standard Calculation Example (Large-Scale Operation)

[0177]

[0178] Other combined power generation methods can be achieved by adjusting the start-up mode, and will not be listed one by one. The technical indicators required for the standard grid calculation case must be met.

[0179] Evaluation Indicator 2: Penetration Rate of New Energy Power Generation

[0180] After setting the power generation operation mode shown in Table 5, the penetration rate of new energy power generation is calculated as follows:

[0181]

[0182] Table 5: Standard Calculation Example of New Energy Power Generation Mode

[0183]

[0184] Evaluation index 3: Frequency response characteristics

[0185] set up Figure 8 Fault F2 in the [section / section]. Based on [the specific details / methods]... Figure 6 Frequency response model calculation Figure 8 The frequency response curve of the standard power grid example is shown, along with the time-domain simulation of the standard power grid example. The analytical calculation results of the equivalent model are compared with the simulation test results to obtain... Figure 9 A comparison of the calculation results of the intermediate-efficiency model (black, corresponding to the frequency response model) and the simulation curve (blue, corresponding to the time-domain simulation) is shown.

[0186] from Figure 9 The maximum frequency deviation was obtained in steady-state frequency deviation Maximum frequency change rate The parameters are shown in Table 6 below.

[0187] Table 6: Key Frequency Indicators

[0188]

[0189] The absolute value of the relative error of each parameter is less than 20%, which meets the requirements of technical indicator 3.

[0190] Evaluation Indicator 4: Short-circuit ratio of multiple power stations at new energy grid connection points

[0191] Based on the analytical and simulation calculation methods for the short-circuit ratio of multiple new energy power plants connected to the grid, the short-circuit ratio of all new energy power plants connected to the grid was calculated, and the calculation results are shown in Table 7 below.

[0192] Table 7: Short-circuit ratio of multiple new energy power stations

[0193]

[0194] It can be seen that the absolute value of the relative error of the short-circuit ratio of each new energy grid connection point is less than 20%, which meets the requirements of technical indicator 4.

[0195] Reference Figure 10 The diagram illustrates a structural block diagram of a regional power grid standard calculation case construction and evaluation device provided by an embodiment of the present invention, which may specifically include:

[0196] The isolated network determination unit 1001 is used to obtain the grid topology of the regional power grid and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology.

[0197] The power grid standard calculation unit 1002 is used to collect power grid parameter information of all islanded grid types in the regional power grid, and construct the power grid standard calculation unit of the regional power grid based on the power grid parameter information and the topology constraints.

[0198] The standard case evaluation unit 1003 is used to evaluate the power grid standard case using multiple indicators and output the case evaluation results.

[0199] In one optional embodiment, the island determination unit 1001 includes:

[0200] The line troubleshooting unit is used to identify at least one isolated network caused by a single fault event through line troubleshooting based on the network topology.

[0201] The island type determination unit is used to determine the island type of each island based on the reason for the formation of the island; the island type is island type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV island, or island type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh island, or island type 3, which is formed by the tripping of a chain-structure 220kV line to form multiple 220kV islands.

[0202] In one optional embodiment, the power grid standard simulation construction unit 1002 includes:

[0203] The information statistics unit is used to count the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level of all isolated grids in the regional power grid, as power grid parameter information for all isolated grid types in the regional power grid.

[0204] In one optional embodiment, the power grid parameter information includes the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level for all isolated grids in the regional power grid; the power grid standard calculation unit 1002 includes:

[0205] The 110kV site quantity model construction unit is used to construct a 110kV site quantity model based on the maximum number of 110kV sites and the average number of 110kV sites, combined with a first quantity coefficient.

[0206] The 220kV site quantity model construction unit is used to construct a 220kV site quantity model based on the maximum number of 220kV sites and the average number of 220kV sites, combined with a second quantity coefficient.

[0207] The power supply installed capacity model construction unit is used to construct a power supply installed capacity model based on the maximum installed capacity and the average installed capacity, combined with the power supply installed capacity coefficient.

[0208] The total load model construction unit is used to construct a total load model based on the maximum load level and the average installed capacity, combined with the total load coefficient.

[0209] A topology constraint construction unit is used to construct topology constraints that consider all islanded network types in the regional power grid.

[0210] The power grid standard calculation case construction sub-unit is used to construct the power grid standard calculation case of the regional power grid based on the 110kV substation quantity model, the 220kV substation quantity model, the total power generation capacity model, the total load model, and the topology constraints.

[0211] In one alternative embodiment, the topology constraints indicate that the constructed standard power grid example must simultaneously satisfy the following constraints:

[0212] Constraint 1: The standard power grid example is a connected network;

[0213] Constraint 2: A single fault event can generate different types of isolated network configurations; the different isolated network types include isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network; isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network; and isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks.

[0214] Constraint 3: The types of power generation and consumption simultaneously include hydropower, thermal power, photovoltaic power generation, wind power generation, energy storage, and load;

[0215] Constraint 4: The grid voltage level includes both 220kV and 110kV.

[0216] In one optional embodiment, the standard test evaluation unit 1003 includes:

[0217] The operation mode adjustment unit is used to flexibly adjust the operation mode of wind, solar, hydro, thermal and storage in the grid standard calculation case by setting different unit grid connection power generation schemes;

[0218] The maximum output penetration rate control unit is used to control the maximum output penetration rate of new energy sources in the grid standard calculation example within a preset penetration rate range by setting different new energy output and synchronous generator output.

[0219] The error comparison and analysis unit is used to compare and analyze the errors of analytical calculations and simulation calculations, and to evaluate the frequency response characteristics and the short-circuit ratio of multiple power stations at new energy grid connection points.

[0220] The example evaluation result output unit is used to output the operation mode adjustment results, maximum output penetration rate control results, frequency response characteristic evaluation results, and multi-station short-circuit ratio evaluation results as the example evaluation results of the power grid standard example.

[0221] In one optional embodiment, the error comparison and analysis unit includes:

[0222] The system inertia calculation unit is used to perform analytical calculations and simulation calculations based on system inertia on the power grid standard calculation example, and obtain the first analytical calculation result and the first simulation calculation result.

[0223] The frequency response characteristic evaluation unit is used to compare the first analytical calculation result with the first simulation calculation result using the maximum frequency deviation, steady-state frequency deviation and maximum frequency change rate as comparison parameters, and to form a frequency response characteristic evaluation result.

[0224] The multi-site short-circuit ratio calculation unit is used to perform analytical calculation and simulation calculation on the standard power grid example based on the multi-site short-circuit ratio of new energy grid connection points, and obtain the second analytical calculation result and the second simulation calculation result.

[0225] The multi-site short-circuit ratio evaluation unit is used to compare the second analytical calculation result with the second simulation calculation result using the relative deviation of the short-circuit ratio as the comparison parameter, thereby forming the multi-site short-circuit ratio evaluation result of the new energy grid connection point.

[0226] As the device embodiment is basically similar to the method embodiment, it is described in a relatively simple way. For relevant details, please refer to the description of the method embodiment above.

[0227] It should be noted that, in order to enable those skilled in the art to better distinguish data of the same type but with different actual meanings, the embodiments of the present invention use terms such as "first" and "second" to distinguish and describe some technical features. The terms "first" and "second" are used only for data differentiation and have no other special meanings. It is understood that the present invention does not impose any limitations on them.

[0228] This invention also provides an electronic device, which includes a processor and a memory:

[0229] The memory is used to store program code and transfer the program code to the processor;

[0230] The processor is used to execute the method for constructing and evaluating regional power grid standard examples according to the instructions in the program code of any embodiment of the present invention.

[0231] This invention also provides a computer-readable storage medium for storing program code, which is used to execute the method for constructing and evaluating regional power grid standard examples according to any embodiment of this invention.

[0232] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0233] In the embodiments provided by this invention, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0234] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0235] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0236] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0237] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for constructing and evaluating standard calculation examples for regional power grids, characterized in that, include: Obtain the grid topology of the regional power grid, and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology; The power grid parameters of the region's power grid, including all islanded grid types, are statistically analyzed. Based on these power grid parameters and topology constraints, a standard power grid example for the region's power grid is constructed. The power grid standard case is evaluated using multiple indicators, and the case evaluation results are output.

2. The method for constructing and evaluating regional power grid standard cases according to claim 1, characterized in that, The step of determining at least one isolated network and the isolated network type of each isolated network based on the network topology includes: Based on the aforementioned network topology, at least one isolated network caused by a single fault event was identified through line troubleshooting. Based on the cause of the formation of isolated networks, the isolated network type of each isolated network is determined; the isolated network type is isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network, or isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network, or isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks.

3. The method for constructing and evaluating regional power grid standard cases according to claim 1, characterized in that, The statistics on the regional power grid include power grid parameter information for all islanded grid types, including: The maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level of all isolated grids in the regional power grid are statistically analyzed and used as the power grid parameter information for the regional power grid including all isolated grid types.

4. The method for constructing and evaluating regional power grid standard cases according to claim 1, characterized in that, The power grid parameter information includes the maximum number of 110kV substations, the maximum number of 220kV substations, the average number of 110kV substations, the average number of 220kV substations, the maximum installed capacity, the maximum load level, the average installed capacity, and the average load level for all isolated grids in the regional power grid. The step of constructing a standard power grid example for the regional power grid based on the power grid parameter information and topology constraints includes: Based on the maximum number of 110kV substations and the average number of 110kV substations, and combined with the first quantity coefficient, a 110kV substation quantity model is constructed. Based on the maximum number of 220kV substations and the average number of 220kV substations, and combined with the second quantity coefficient, a 220kV substation quantity model is constructed. Based on the maximum installed capacity and the average installed capacity, and combined with the power supply installed capacity coefficient, a model of total power supply installed capacity is constructed. Based on the maximum load level and the average installed capacity, and combined with the total load factor, a total load model is constructed; Construct topology constraints that consider all islanded network types in the regional power grid; Based on the 110kV substation quantity model, the 220kV substation quantity model, the total installed power capacity model, the total load model, and the topology constraints, a standard power grid example for the regional power grid is constructed.

5. The method for constructing and evaluating regional power grid standard cases according to claim 4, characterized in that, The topology constraints state that the constructed standard power grid example must simultaneously satisfy the following constraints: Constraint 1: The standard power grid example is a connected network; Constraint 2: A single fault event can generate different types of isolated network configurations; the different isolated network types include isolated network type 1, which is formed by the tripping of a 220kV main transformer to form a 110kV isolated network; isolated network type 2, which is formed by the tripping of a 220kV line to form a 220kV mesh isolated network; and isolated network type 3, which is formed by the tripping of a chain-structured 220kV line to form multiple 220kV isolated networks. Constraint 3: The types of power generation and consumption simultaneously include hydropower, thermal power, photovoltaic power generation, wind power generation, energy storage, and load; Constraint 4: The grid voltage level includes both 220kV and 110kV.

6. The method for constructing and evaluating regional power grid standard cases according to claim 1, characterized in that, The evaluation of the power grid standard case study using multiple indicators, and the output of the case study evaluation results, include: By setting different grid-connected power generation schemes, the operation mode of wind, solar, hydro, thermal and storage in the standard grid calculation example can be flexibly adjusted; By setting different new energy power outputs and synchronous generator outputs, the maximum power output penetration rate of new energy in the power grid standard calculation example is controlled within a preset penetration rate range. By combining the error comparison analysis of analytical calculation and simulation calculation, the frequency response characteristics and the short-circuit ratio of multiple power stations at new energy grid connection points are evaluated respectively. The results of the output operation mode adjustment, the maximum output permeability control, the frequency response characteristic evaluation, and the short-circuit ratio evaluation of multiple substations are used as the evaluation results of the standard power grid calculation.

7. The method for constructing and evaluating regional power grid standard cases according to claim 6, characterized in that, The error comparison analysis combining analytical calculations and simulation calculations is used to evaluate frequency response characteristics and the short-circuit ratio of multiple power stations at new energy grid connection points, including: Analytical and simulation calculations based on system inertia were performed on the aforementioned standard power grid calculation examples to obtain the first analytical calculation results and the first simulation calculation results. Using the maximum frequency deviation, steady-state frequency deviation, and maximum frequency change rate as comparison parameters, the first analytical calculation result is compared with the first simulation calculation result to form a frequency response characteristic evaluation result. The standard power grid example was subjected to analytical and simulation calculations based on the short-circuit ratio of multiple power stations at the new energy grid connection point, and the second analytical calculation results and the second simulation calculation results were obtained. Using the relative deviation of the short-circuit ratio as a comparison parameter, the second analytical calculation result is compared with the second simulation calculation result to form the short-circuit ratio evaluation result of multiple power stations for new energy grid connection points.

8. A device for constructing and evaluating standard calculation examples for regional power grids, characterized in that, include: An isolated network determination unit is used to obtain the grid topology of a regional power grid and determine at least one isolated network and the isolated network type of each isolated network based on the grid topology. The power grid standard case construction unit is used to collect power grid parameter information of all islanded grid types in the regional power grid, and construct the power grid standard case of the regional power grid based on the power grid parameter information and topology constraints. The standard case evaluation unit is used to evaluate the power grid standard case using multiple indicators and output the case evaluation results.

9. An electronic device, characterized in that, The device includes a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the method for constructing and evaluating regional power grid standard examples according to any one of claims 1-7, based on the instructions in the program code.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store program code for executing the regional power grid standard example construction and evaluation method according to any one of claims 1-7.

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