A method and system for post-disaster islanding division of a power system

Abstract

The present invention discloses a method and system for post-disaster islanding division of a power system. The method includes performing simulation analysis on the acquired data to determine the circuit topology structure; performing simulation on the circuit topology structure; performing iterative processing on the simulation output results to obtain reference splitting points, and determining reference splitting boundaries according to the reference splitting points; calculating the stability region boundaries of the variables at the reference splitting points based on stability region estimation to obtain reference splitting boundaries; outputting the final splitting priority according to the voltage stability margin of the reference splitting boundaries; determining the active splitting boundaries under different disaster conditions based on the selected standard conditions and splitting priorities, and determining the active splitting regions of the target distribution network based on the active splitting boundaries; during the process of dividing the post-disaster island power grid, implementing the splitting strategy corresponding to the active splitting region matching the disaster conditions. The method for post-disaster islanding division of the power system provided by the present invention can optimize the process of islanding division of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of emergency repair scheduling of power systems, and in particular to a method and system for dividing post-disaster islands of a power system. Background Art

[0002] With the change of environmental climate, various extreme weather disaster events occur frequently. The characteristics of wide distribution, many lines, and large number of users of the distribution network determine that it is extremely vulnerable to natural disasters, resulting in large-scale power outages. Therefore, it is necessary to achieve reliable and continuous power supply for critical loads through island division after natural disaster events occur.

[0003] In the prior art, conventional island division is carried out for all regions, but too many islands will make it extremely complicated for the power grid to coordinate the operation status and load changes of each island. Therefore, how to optimize the island division process of the power system has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0004] The present invention provides a method and system for dividing post-disaster islands of a power system to solve the technical problem of how to optimize the island division of the power system and achieve the effect of power supply for critical loads. The method for dividing post-disaster islands of the power system includes:

[0005] Performing simulation analysis on the obtained disaster data of the disaster area and the initial power data of the target distribution network to determine the circuit topology structure corresponding to the current normal operation requirements;

[0006] Constructing a power grid simulation operation model based on the circuit topology structure and obtaining the output result of the power grid simulation operation model;

[0007] Performing iterative processing on the output result by using the Newton-Raphson method to obtain a reference splitting point, and determining a reference splitting boundary according to the reference splitting point; wherein, the reference splitting boundary is configured to calculate the stable domain boundary of the variable at the reference splitting point according to the stable domain estimation to obtain the reference splitting boundary;

[0008] Outputting the final splitting priority according to the voltage stability margin of the reference splitting boundary;

[0009] Determining the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determining the active splitting area of the target distribution network based on the active splitting boundary;

[0010] During the division process of the post-disaster island power grid of the target distribution network, implementing the splitting strategy corresponding to the active splitting area matching the current disaster condition.

[0011] As one of the preferred solutions, before performing simulation analysis on the disaster-affected data of the obtained disaster area and the initial power data of the target distribution network, the post-disaster islanding division method of the power system further includes:

[0012] Preprocess the disaster-affected data of the disaster area and the initial power data of the target distribution network. The preprocessing steps include data cleaning, standardization of the disaster-affected data, and normalization of the initial power data.

[0013] As one of the preferred solutions, the construction process of the circuit topology structure includes:

[0014] Perform spatial overlay analysis on the geographical scope of the disaster area and the geographical location of the target distribution network to determine the power facilities affected by the disaster in the target distribution network;

[0015] Calculate the power flow parameters of the power facilities based on the fast decoupled power flow algorithm, and construct the circuit topology structure corresponding to the current normal operation requirements based on the power facilities and the power flow parameters.

[0016] As one of the preferred solutions, the output results of the power grid simulation operation model include one or more of the following: node voltage amplitude, phase angle, current, and line power flow direction and magnitude.

[0017] As one of the preferred solutions, the use of the Newton-Raphson method to perform iterative processing on the output results to obtain the reference splitting point includes:

[0018] Construct a nonlinear equation system according to Kirchhoff's voltage law and the output results, perform iterative processing on the nonlinear equation system to obtain the Jacobian matrix, and the Newton-Raphson method obtains the reference splitting point based on the Jacobian matrix in each iterative process.

[0019] As one of the preferred solutions, the calculation process of the stability region boundary includes:

[0020] Substitute the variables of the reference splitting point obtained by the Newton-Raphson method into the circuit topology structure to construct a Lyapunov function, and use the Lyapunov function method to calculate the derivative of the Lyapunov function, and determine the stability region boundary when the derivative of the Lyapunov function is zero or less than a preset threshold.

[0021] As one of the preferred solutions, before outputting the final splitting priority with the voltage stability margin of the reference splitting boundary, the post-disaster islanding division method of the power system further includes:

[0022] Obtain the voltage critical value and the actual voltage amplitude of the reference splitting boundary in the target distribution network, and calculate the voltage stability margin of the reference splitting boundary. Among them, the process of obtaining the voltage critical value of the reference splitting boundary is configured to use the Lyapunov function method for stability domain estimation, and according to the constraint conditions of the circuit topology structure, solve the voltage critical value when the derivative of the Lyapunov function is zero.

[0023] As one of the preferred solutions, after determining the active splitting area of the target distribution network based on the active splitting boundary, the post-disaster islanding division method of the power system further includes:

[0024] Based on the Newton-Raphson method, simulate the power grid flow data of the active splitting area. If the local flow is abnormal, then calculate the node power-voltage amplitude curve of the active splitting area according to the voltage stability analysis to optimize the active splitting area.

[0025] As one of the preferred solutions, the local flow abnormal conditions include one or more of the following: the flow value on the line exceeds the rated current-carrying capacity, the voltage amplitude of the node exceeds the rated voltage, and the power is unbalanced.

[0026] Another embodiment of the present invention provides a post-disaster islanding division system for a power system, including:

[0027] A simulation module, configured to perform simulation analysis on the disaster-affected data of the obtained disaster area and the initial power data of the target distribution network to determine the circuit topology structure corresponding to the current normal operation requirements;

[0028] An acquisition module, configured to construct a power grid simulation operation model based on the circuit topology structure and obtain the output result of the power grid simulation operation model;

[0029] An iteration module, configured to perform iterative processing on the output result using the Newton-Raphson method to obtain a reference splitting point, and determine a reference splitting boundary according to the reference splitting point; among them, the reference splitting boundary is configured to perform stable domain boundary calculation on the variables at the reference splitting point according to stable domain estimation to obtain the reference splitting boundary;

[0030] An output module, configured to output the final splitting priority with the voltage stability margin of the reference splitting boundary;

[0031] A determination module, configured to determine the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determine the active splitting area of the target distribution network based on the active splitting boundary;

[0032] An execution module, configured to execute a disconnection strategy corresponding to the active disconnection area that matches the disaster conditions during the division of the post-disaster island power grid of the target distribution network.

[0033] Compared with the prior art, the beneficial effects of the embodiments of the present invention are at least one of the following:

[0034] (1) This method uses the Newton-Raphson method for iterative processing to obtain reference disconnection points, providing accurate initial data for the stable region estimation. The stable region estimation then calculates the stable region boundary based on the variables at these reference disconnection points, thereby accurately determining the reference disconnection boundary; the combination of the Newton-Raphson method and the stable region estimation enables the accurate identification of the key positions in the power grid that cause system instability, providing a reliable basis for the disconnection operation of the power grid;

[0035] (2) The stable region estimation can evaluate the stability of the power grid as a whole. By calculating the stable region boundary, the stable range of the power grid under different operating states can be determined, thereby optimizing the island division process of the power system. Description of the Drawings

[0036] Figure 1 is a schematic flowchart of the post-disaster island division method for a power system in one embodiment of the present invention;

[0037] Figure 2 is a schematic structural diagram of the post-disaster island division system for a power system in one embodiment of the present invention.

[0038] Reference Numerals:

[0039] Among them, 11, simulation module; 12, acquisition module; 13, iteration module; 14, output module; 15, determination module; 16, execution module. Detailed Embodiments

[0040] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0041] In the description of this application, the terms "first", "second", "third", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", "third", etc. may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0042] In the description of this application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "connected to" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. The terms "vertical", "horizontal", "left", "right", "up", "down" and similar expressions used herein are only for the purpose of illustration and do not indicate or imply that the indicated device or component must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] In the description of this application, it should be noted that unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the technical field to which this technology belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] An embodiment of the present invention provides a method for dividing a post-disaster island in a power system. Specifically, please refer to Figure 1 , Figure 1 which is shown as a schematic flowchart of the method for dividing a post-disaster island in a power system in one embodiment of the present invention. The method includes:

[0045] S1: Perform simulation analysis on the disaster-affected data of the disaster area and the initial power data of the target distribution network to determine the circuit topology structure corresponding to the current normal operation requirements;

[0046] S2: Build a power grid simulation operation model based on the circuit topology structure and obtain the output result of the power grid simulation operation model;

[0047] S3: Use the Newton-Raphson method to perform iterative processing on the output result to obtain a reference splitting point, and determine a reference splitting boundary according to the reference splitting point; wherein, the reference splitting boundary is configured to perform a stable region boundary calculation on the variables at the reference splitting point according to the stable region estimation to obtain the reference splitting boundary;

[0048] S4: Output the final splitting priority with the voltage stability margin of the reference splitting boundary;

[0049] S5: Determine the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determine the active splitting region of the target distribution network based on the active splitting boundary;

[0050] S6: During the division of the post-disaster island power grid of the target distribution network, execute the splitting strategy corresponding to the active splitting region that matches the disaster conditions.

[0051] In S1, obtain the disaster-affected data of the disaster area and the initial power data of the target distribution network. Among them, under different disaster conditions, the disaster-affected data is different. Taking the flood disaster as an example, the obtained disaster-affected data includes parameters such as the inundation water level and inundation time, and the initial power data of the target distribution network includes power grid operation data and equipment monitoring data of substations, etc. After preprocessing these data, the preprocessing steps include data cleaning, standardization of disaster-affected data, and normalization of initial power data. Use simulation software, such as MATLAB / Simulink, PSCAD / EMTDC, OpenDSS, etc., to perform simulation analysis on these data, perform spatial overlay analysis on the geographical scope of the disaster area and the geographical location of the target distribution network, determine the power facilities affected by the disaster in the target distribution network, calculate the power flow parameters of the power facilities based on the fast decoupled power flow algorithm, and construct the circuit topology structure corresponding to the current normal operation requirements based on the power facilities and the power flow parameters. The circuit topology structure is the basis of the power grid simulation operation model, which can describe in detail the connection relationship between each component (such as generators, transformers, lines, loads, etc.) in the power grid under natural disaster conditions.

[0052] Specifically, taking flood disasters as an example, the preprocessing of disaster-affected data can accurately locate the positions of power poles buried by debris flows through high-resolution satellite images. Close-range inspections by drones can clearly show the details of damage and deformation of the outer shells of substation equipment, assisting in judging the impact on internal components; the preprocessing of the initial power data of the target distribution network can cross-check the initial power data from different sources by using data verification algorithms, removing outliers and filling in missing values; the Grubbs criterion based on statistical principles is used to identify outliers in current and power data; with the help of interpolation methods, based on the parameters of surrounding normal nodes, the key node voltage data missing due to sensor failures is supplemented to ensure that the circuit topology structure corresponds to the current normal operation requirements.

[0053] For the local power grid where the disaster-affected power facilities have been determined, a corresponding nodal admittance matrix is constructed. The nodal admittance matrix reflects the electrical connection relationships between nodes in the power grid and the electrical parameters (such as conductance, susceptance, reactance, etc.) of components such as lines and transformers, and is the basic data structure for power flow calculations.

[0054] The fast decoupled power flow algorithm is used for iterative calculations, and finally the power flow parameters such as the voltage magnitude, phase angle of each node, and the active power and reactive power of each line are obtained. Based on the power facilities and power flow parameters, a circuit topology structure corresponding to the current normal operation requirements is constructed.

[0055] Using the circuit topology structure to construct a power grid simulation operation model, the output results of the power grid simulation operation model can be obtained.

[0056] Specifically, for the power grid simulation operation model constructed based on the circuit topology structure, its steady-state operation follows the power system power flow equation. For a power grid with n nodes, the power flow equation in the commonly used polar coordinate form is used to describe, and the nodal power equation can be written as:

[0057] For load nodes, the active power equation is:

[0058]

[0059] The reactive power equation is:

[0060]

[0061] Among them, among them 、 are the injected active and reactive powers of node i, is the voltage magnitude of the node, is the voltage phase angle difference between node i and node j, and are the real and imaginary part elements of the nodal admittance matrix respectively.

[0062] For the generator node, the active power is known and the voltage amplitude . By solving the above active power equation and the supplementary voltage amplitude constraint equation simultaneously.

[0063] Among them, the voltage amplitude constraint equation is , where is the set value of the voltage amplitude of this node.

[0064] On the basis of obtaining the power grid simulation operation model, set the simulation conditions, which include normal operation, contingency faults (such as line short circuits, generator tripping, etc.), load peak impact scenarios, etc. The model outputs multiple results, and the output results include the voltage amplitude and phase angle of each node, as well as the power flow direction and magnitude of the line, etc., which helps to detect overload hidden dangers and voltage over-limit problems.

[0065] In S3, according to Kirchhoff's voltage law and the output results of the power grid simulation operation model, a nonlinear equation set is constructed, and the Jacobi matrix is obtained by iterative processing of the nonlinear equation set. The Newton-Raphson method obtains the reference solution point based on the Jacobi matrix in each iteration process. The specific calculation process is as follows.

[0066] Specifically, Kirchhoff's voltage law states that in any closed loop, the algebraic sum of the voltage drops across each component is equal to zero. For the circuit topology of the power system, this means that along each closed loop in the power grid, the voltage equations listed according to the characteristics of the components such as the voltage drops corresponding to resistance and reactance and the electromotive force of the power source must satisfy the condition that the sum is zero. Therefore, a nonlinear equation set is constructed based on Kirchhoff's voltage law and the output results of the power grid simulation operation model.

[0067] To solve the above constructed nonlinear equation set, an iterative method is usually adopted. The Newton-Raphson method is a commonly used efficient iterative algorithm. Its core idea is to first give the initial values of the variables of the equation set, and then continuously correct the initial values to gradually approach the exact solution of the equation set.

[0068] In each iteration process, it is necessary to calculate the partial derivatives of each equation in the nonlinear equation set with respect to each variable, and arrange these partial derivatives according to certain rules to form the Jacobi matrix.

[0069] After obtaining the Jacobi matrix, use the iterative formula of the Newton-Raphson method to update the values of the variables. For the above nonlinear equation set, let the variable vector be , the equation vector be , and the Jacobi matrix be . Then the iterative formula is:

[0070]

[0071] Among them, represents the number of iterations.

[0072] By continuously repeating this iterative process until a certain convergence condition is met, the variable values obtained at this time are the solutions of the system of equations.

[0073] After iterative convergence, analyze the electrical quantities such as the voltages and currents of each node obtained. Those nodes showing special situations, such as the voltage amplitude approaching the lower limit allowed by the system (if the voltage is too low, it will cause the equipment to malfunction), the line power flow approaching the thermal stability limit (that is, the transmission power approaching the maximum power that the line can carry), or the Jacobian matrix approaching singularity (which means the system is in a very unstable state and a small perturbation may cause large changes), will be marked as reference splitting points. Once a fault or other abnormal situation occurs in the area where these points are located, the power grid is very likely to become unstable, which is a key vulnerable part of the power grid structure.

[0074] In S3, according to the stability region estimation, calculate the stability region boundary for the variables at the reference splitting points to obtain the reference splitting boundary.

[0075] Specifically, the stability region estimation is based on the relevant theories of power system stability. The power system is regarded as a dynamic system. After being perturbed, the trajectory of the system state variables over time determines whether the system can maintain stable operation. The system state variables include those voltages, currents, phase angles, etc. at the reference splitting points. If the trajectory of the system state variables can finally converge to a stable equilibrium point, then the system is stable; otherwise, if the trajectory diverges or enters an uncontrollable state, the system will become unstable.

[0076] Construct a Lyapunov function for the variables at the reference splitting points obtained by the Newton-Raphson method. Using the Lyapunov function method, calculate the derivative of the Lyapunov function and set it equal to zero or less than a certain threshold to determine the stability region boundary.

[0077] At the same time, according to the voltage critical value when the derivative of the Lyapunov function is zero and the actual voltage amplitude in the target distribution network, the voltage stability margin of the reference splitting boundary can be calculated, and the splitting priority is determined with reference to its voltage stability margin.

[0078] Specifically, the voltage stability margin is an index to measure the voltage stability of the power system. It represents how much safety margin the system has from the voltage instability state under the current operating state. Simply put, it is how much perturbation (such as load increase, generator failure, etc.) the system can withstand without causing voltage collapse.

[0079] When determining the active splitting area and splitting strategy, for areas with low voltage stability margins, they are more likely to experience voltage instability when the system is disturbed. Therefore, they will be given priority in the splitting priority ranking. For example, during a fault, those areas with voltage stability margins close to zero are preferentially split to isolate the unstable part from the main power grid, prevent the spread of the fault, and ensure the power supply safety of other areas.

[0080] Under different disaster conditions, the splitting priorities are different. The splitting priorities can also be controlled manually or through different consideration factors, such as load importance and disaster type targeting. Taking load importance as an example, different types of loads are distinguished. Those related to public safety and emergency rescue, such as hospitals, fire departments, and transportation hubs, belong to the first-level critical loads and must be given priority to ensure power supply; general industrial enterprises, large commercial centers, etc. can be classified as second-level loads. Power outages will cause certain economic losses but can be tolerated for a certain period of time relatively; ordinary residential communities, etc. are regarded as third-level loads, and the impact of power outages is mainly on the convenience of life. According to this load classification, when determining the active splitting boundary, priority is given to ensuring the stable power supply in the areas where critical loads are located and reasonably including or excluding them from different active splitting areas.

[0081] Surrounding high-priority nodes and areas, draw the initial active splitting boundary based on their electrical connection characteristics, the surrounding power grid topology structure, etc. Subsequently, make dynamic adjustments in combination with the situation of low-priority areas. For example, when the risk of fault propagation increases in a low-priority area due to changes in the surrounding environment (such as power flow transfer caused by adjacent line faults making it face new risks), expand the active splitting boundary in a timely manner to ensure that the boundary can cover all areas that may become unstable and require splitting operations under disaster conditions, so as to accurately determine the active splitting area of the target distribution network.

[0082] It is also possible to simulate the power grid power flow data of the active splitting area based on the Newton-Raphson method. If the local power flow is abnormal, then calculate the node power-voltage amplitude curve for the active splitting area according to the voltage stability analysis to optimize the active splitting area.

[0083] The local power flow abnormal conditions include one or more of the following: the power flow value on the line exceeds the rated current-carrying capacity, the voltage amplitude of the node exceeds the rated voltage, and power imbalance, where the power imbalance includes active power imbalance and reactive power imbalance.

[0084] An embodiment of the present invention provides a post-disaster island division system for a power system. Specifically, please refer to Figure 2 , Figure 2 which shows a schematic structural diagram of the post-disaster island division system for a power system in one embodiment of the present invention. The system includes:

[0085] The simulation module 11 is used to perform simulation analysis on the disaster-affected data of the disaster area and the initial power data of the target distribution network, and determine the circuit topology structure corresponding to the current normal operation requirements;

[0086] The acquisition module 12 is used to construct a power grid simulation operation model based on the circuit topology structure and obtain the output result of the power grid simulation operation model;

[0087] The iteration module 13 is used to perform iterative processing on the output result by using the Newton-Raphson method to obtain a reference splitting point, and determine a reference splitting boundary according to the reference splitting point; wherein, the reference splitting boundary is configured to perform a stable domain boundary calculation on the variables at the reference splitting point according to the stable domain estimation to obtain the reference splitting boundary;

[0088] The output module 14 is used to output the final splitting priority with the voltage stability margin of the reference splitting boundary;

[0089] The determination module 15 is used to determine the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determine the active splitting area of the target distribution network based on the active splitting boundary;

[0090] The execution module 16 is used to execute the splitting strategy corresponding to the active splitting area matching the disaster conditions during the division of the post-disaster island power grid of the target distribution network.

[0091] Compared with the prior art, the beneficial effects of the embodiments of the present invention are at least one of the following:

[0092] (1) This method uses the Newton-Raphson method for iterative processing to obtain a reference splitting point, which provides accurate initial data for the stable domain estimation, and the stable domain estimation calculates the stable domain boundary according to the variables at these reference splitting points, so as to accurately determine the reference splitting boundary; the combination of the Newton-Raphson method and the stable domain estimation enables the key positions that cause the system to become unstable to be accurately found in the power grid, providing a reliable basis for the splitting operation of the power grid;

[0093] (2) The stable domain estimation can evaluate the stability of the power grid as a whole. By calculating the stable domain boundary, the stable range of the power grid under different operating states can be determined, so as to formulate more reasonable power grid control strategies.

[0094] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention shall be subject to the appended claims.

Claims

1. A method for post-disaster islanding division of a power system, characterized in that, Including: Performing simulation analysis on the disaster-affected data of the disaster area and the initial power data of the target distribution network to determine the circuit topology structure corresponding to the current normal operation requirements; Constructing a power grid simulation operation model based on the circuit topology structure and obtaining the output results of the power grid simulation operation model; Performing iterative processing on the output results using the Newton-Raphson method to obtain a reference splitting point, and determining a reference splitting boundary according to the reference splitting point; wherein, the reference splitting boundary is configured to calculate the stable domain boundary of the variables at the reference splitting point according to the stable domain estimation to obtain the reference splitting boundary; Outputting the final splitting priority with the voltage stability margin of the reference splitting boundary; Determining the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determining the active splitting area of the target distribution network based on the active splitting boundary; Achieving reliable continuous power supply for critical loads through the means of island division; Simulating the power flow data of the active splitting area based on the Newton-Raphson method. If the local power flow is abnormal, calculating the node power-voltage amplitude curve for the active splitting area according to the voltage stability analysis to optimize the active splitting area; During the process of dividing the post-disaster island power grid of the target distribution network, implementing the splitting strategy corresponding to the active splitting area matching the current disaster conditions.

2. The method for post-disaster islanding division of the power system according to claim 1, characterized in that, Before performing simulation analysis on the disaster-affected data of the obtained disaster area and the initial power data of the target distribution network, the method for post-disaster island division of the power system further includes: Preprocessing the disaster-affected data of the disaster area and the initial power data of the target distribution network, and the preprocessing steps include data cleaning, standardization of the disaster-affected data, and normalization of the initial power data.

3. The method for post-disaster islanding division of the power system according to claim 1, wherein, The construction process of the circuit topology structure includes: Performing spatial overlay analysis on the geographical scope of the disaster area and the geographical location of the target distribution network to determine the power facilities affected by the disaster in the target distribution network; Calculating the power flow parameters of the power facilities based on the fast decoupled power flow algorithm, and constructing the circuit topology structure corresponding to the current normal operation requirements based on the power facilities and the power flow parameters.

4. The method for post-disaster islanding division of the power system according to claim 1, characterized in that, The output results of the power grid simulation operation model include one or more of the following: node voltage amplitude, phase angle, current, and line power flow direction and magnitude.

5. The post-disaster islanding division method of the power system according to claim 1, characterized in that The process of obtaining the reference splitting point by performing iterative processing on the output results using the Newton-Raphson method includes: Constructing a nonlinear equation set according to Kirchhoff's voltage law and the output results, performing iterative processing on the nonlinear equation set to obtain a Jacobian matrix, and the Newton-Raphson method obtaining the reference splitting point based on the Jacobian matrix in each iterative process.

6. The post-disaster islanding division method for the power system according to claim 1, characterized in that, The calculation process of the stable domain boundary includes: Substituting the variables of the reference splitting point obtained by the Newton-Raphson method into the circuit topology structure to construct a Lyapunov function, and using the Lyapunov function method to calculate the derivative of the Lyapunov function, and determining the stable domain boundary when the derivative of the Lyapunov function is zero or less than a preset threshold.

7. The method for post-disaster islanding division of the power system according to claim 1, wherein, Before outputting the final splitting priority with the voltage stability margin of the reference splitting boundary, the post-disaster islanding division method of the power system further includes: Obtaining the voltage critical value and the actual voltage amplitude of the reference splitting boundary in the target distribution network, and calculating the voltage stability margin of the reference splitting boundary. Among them, the obtaining process of the voltage critical value of the reference splitting boundary is configured to solve the voltage critical value when the derivative of the Lyapunov function is zero according to the constraint conditions of the circuit topology structure when using the Lyapunov function method for stability domain estimation.

8. The method for post-disaster islanding division of the power system according to claim 1, characterized in that The local power flow abnormal conditions include one or more of the following: the power flow value on the line exceeds the rated carrying capacity, the voltage amplitude of the node exceeds the rated voltage, and the power imbalance.

9. A post-disaster islanding division system for a power system, characterized in that, It includes: A simulation module, configured to perform simulation analysis on the disaster data of the obtained disaster area and the initial power data of the target distribution network to determine the circuit topology structure corresponding to the current normal operation requirements; An acquisition module, configured to construct a power grid simulation operation model based on the circuit topology structure and obtain the output result of the power grid simulation operation model; An iteration module, configured to perform iterative processing on the output result using the Newton-Raphson method to obtain a reference splitting point, and determine a reference splitting boundary according to the reference splitting point; among them, the reference splitting boundary is configured to calculate the stability domain boundary of the variables at the reference splitting point according to the stability domain estimation to obtain the reference splitting boundary; An output module, configured to output the final splitting priority with the voltage stability margin of the reference splitting boundary; A determination module, configured to determine the active splitting boundary under different disaster conditions based on the selected standard conditions and the splitting priority, and determine the active splitting area of the target distribution network based on the active splitting boundary; An execution module, configured to execute the splitting strategy corresponding to the active splitting area that matches the current disaster condition during the division process of the post-disaster island power grid of the target distribution network.

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