Power distribution network reconstruction method

Abstract

The invention belongs to the technical field of power distribution networks, and particularly relates to a power distribution network reconstruction method, which comprises the following steps of: A1, constructing a power distribution network topology model based on a graph database, converting power equipment into nodes, establishing a static connection relationship according to a CIM / E standard, and superposing dynamic topology connection according to a real-time switch state; a2, combining a guiding algorithm, an orthogonal layout algorithm and a hierarchical layout algorithm, automatically generating an inter-master-station connection wiring diagram, and displaying a complex connection path between power distribution network equipment; a3, according to the bus state, the contact path and the line margin, automatically generating a large-area power failure transfer scheme, including supply line selection, load priority calculation and a dynamic adjustment strategy; the graph database technology is adopted for distribution network contact calculation, the concept modeling of the graph is more in line with an equipment connection relation model in a power grid, and compared with a traditional relation database mode, the whole distribution network contact relation can be expressed more rapidly, more accurately and more clearly.

Description

Technical Field

[0001] The present invention belongs to the technical field of power distribution networks, and in particular relates to a power distribution network reconstruction method. Background Art

[0002] Currently, the dispatching automation system and the distribution network master station system have many shortcomings in equipment model storage and power supply communication display, fault response and interactive operation.

[0003] In terms of device model storage, traditional relational databases store the connection relationships of device models, and querying and modeling takes a long time. However, the connection relationships of power grid devices are naturally in line with the design principles of graph databases that use points and edges as basic storage units and efficiently store and query graph data. Graph databases directly store node dependencies, and associations can add labels, directions, and attributes. After device modeling, the query efficiency far exceeds that of traditional databases. Therefore, this project attempts to use graph databases to store device models and calculate connection relationships.

[0004] At the power supply connection display level, although the dispatching automation and distribution network master station system has single feeder detailed diagrams and simplified diagrams, it lacks intuitive substation outgoing line switch connection path diagrams, making it difficult for staff to quickly and clearly understand the power supply connection path. This project will try to use algorithms such as force-directed layout and hierarchical layout to automatically generate connection diagrams to fill the gap.

[0005] When a distribution network failure, such as a complete substation outage causing a widespread power outage, quickly restoring the power supply area becomes a key challenge for distribution network dispatchers. Existing distribution networks lack digital solutions and fast, reliable power restoration technologies.

[0006] In the field of interactive operation, users of the distribution network master station system can operate switch devices in a single feeder diagram. However, when transferring power over a large area, there is a lack of fast serial operation methods for multiple feeder switches, and the changes in the power supply path after the switch operation cannot be intuitively presented.

[0007] To this end, the present invention provides a distribution network reconstruction method. Summary of the Invention

[0008] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0009] The technical solution adopted by the present invention to solve the technical problem is: a distribution network reconstruction method described in the present invention includes the following steps: A1. Build a distribution network topology model based on a graph database, convert power equipment into nodes, establish static connection relationships according to CIM / E standards, and overlay dynamic topology connections based on real-time switch status; A2. Combining the force-oriented algorithm, orthogonal layout algorithm, and hierarchical layout algorithm, it automatically generates a connection diagram between master stations, showing the complex connection paths between distribution network equipment. A3. Automatically generate a large-scale power outage transfer plan based on busbar status, interconnection paths, and line margins, including power supply line selection, load priority calculation, and dynamic adjustment strategies; A4. The power transfer plan is executed in real time through a visual interactive interface, which supports dispatchers to operate item by item or jump items, and simultaneously displays the changes in the power supply path and the power supply status.

[0010] Preferably, in step A1, the static connection relationship is established in the following manner: Device to node number to device; The dynamic topology connection method is: According to the switch telesignaling status, delete the dynamic connection of the opening switch and create the dynamic connection of the closing switch; Distinguish static and dynamic topological relationships in the same graph by overlaying labels.

[0011] Preferably, in step A2: The force-directed algorithm iteratively optimizes the layout by simulating the attractive and repulsive forces between nodes; The orthogonal layout algorithm ensures that edges do not cross and nodes are hierarchically aligned; The hierarchical layout algorithm reduces edge crossings and maintains the hierarchical structure.

[0012] Preferably, in step A3, the calculation formula of the line margin is: -OC-C ; in, is the upper limit of the outgoing switch current at the opposite end, is the load factor, OC is the current value of the outgoing line switch at the opposite end, C The current value of the outgoing switch at this end; when When ≥0, it is determined to be a power supply line.

[0013] Preferably, in step A3, dynamically adjusting the strategy includes the following steps: D1. Accumulate the load values ​​of the supplied lines in order of priority. If the total load exceeds the margin, the lines without interconnection and the lines without the first switch and three remote control are kept first; D2. Optimize the supply plan by shedding load, supplying to the opposite end, or actively supplying; Among them, the current value set of the line without tie switch is recorded as ; The first switch is not a three-way remote control or there is no first switch, and the current value set is recorded as ; The tie switch is not a three-way remote control, and the current value set is recorded as ; The first switch is three-remote and the tie switch is three-remote, the current value set is recorded as .

[0014] Preferably, the step of actively supplying comprises: E1. Select busbar A with external connection, and supply busbar B without external connection through its outgoing switch S1; E2. Open the S1 switch or the first switch, and the other end of the S1 line will supply bus B, and the other outgoing switch S2 of bus A will supply bus A.

[0015] Preferably, in step A4, the visual interactive interface is developed based on the Java Swing framework, and the MVC pattern is used to separate the data model and the view; Design principles include: The interface follows the principles of simplicity, clarity, consistency, focus, and interactivity; Displays changes in power supply range and load transfer paths after switch operations in real time.

[0016] Preferably, the functions of the visual interactive interface include: Execute the transfer operation item by item or skip items; Automatically trigger the regeneration of the transfer plan when the operation fails; Color coding and dynamic graphics highlight key power status.

[0017] Preferably, in the distribution network topology model, the power supply range analysis step includes: F1. Extract the distribution network label subgraph and calculate the weakly connected components to divide the electrical islands. F2. Combine path search and bidirectional detection to determine the set of power-off devices downstream of the switch.

[0018] Preferably, during the generation of the inter-master station connection diagram, the user is allowed to specify node alignment and grouping constraints, and node overlap is avoided by automatically generating layout constraints.

[0019] The beneficial effects of the present invention are as follows: 1. This invention uses graph database technology for distribution network connection calculation. The conceptual modeling of the graph is more consistent with the equipment connection relationship model in the power grid. Compared with the traditional relational database method, it is faster and can more accurately and clearly express the entire distribution network connection relationship. 2. This invention uses multiple layout technologies in automatic mapping. Using a single layout method would be difficult to achieve the distribution network connection diagram proposed in this project. Therefore, multiple algorithms are combined in the entire mapping process. 3. This invention designs and automatically generates power transfer plans for various scenarios, including busbar failures, busbar maintenance, station-wide power outages, and main transformer overloads, taking into account distribution network connectivity and line margins. This greatly reduces the pressure and time consumption of power transfer. 4. The present invention displays the sequence of switch operations required for power transfer in a single interface, allowing dispatchers to perform actual control operations and avoid multiple feeder jumps through the distribution network master station system to perform switch operations. At the same time, the changes in the power supply path after the switch operation are displayed graphically. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below with reference to the accompanying drawings.

[0021] Figure 1 is a flow chart of the reconstruction method of the present invention; Figure 2 is a flow chart of the dynamic adjustment strategy in the present invention; Figure 3 This is a flow chart of the active supply in the present invention; Figure 4 It is a flow chart of the power supply range analysis in the present invention; Figure 5 It is a schematic diagram of the node layout in the present invention; Figure 6 It is a calculation process framework diagram in the present invention; Figure 7 and Figure 8 This is a schematic diagram of the power supply scheme in the present invention. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0023] like Figures 1 to 4 As shown, a distribution network reconstruction method according to an embodiment of the present invention includes the following steps: A1. Build a distribution network topology model based on a graph database, convert power equipment into nodes, establish static connection relationships according to CIM / E standards, and overlay dynamic topology connections based on real-time switch status; The power system model data complies with the CIM / E standard and describes the objects within the power system in the form of a relational table. Under the CIM / E standard, conductive devices form static connections through the same node number and form dynamic connections through actual switch states.

[0024] In graph database design, static connection topology is mainly used, and dynamic connection topology is constructed on the static connection topology. The following principles are followed: maximize the efficiency of topology search; reduce ring connection relationships between devices as much as possible, and use star connection relationships as much as possible; minimize the creation of nodes; minimize the creation of relationships; and consider the universality of electrical wiring diagrams.

[0025] In step A1, the static connection relationship is established in the following manner: Device to node number to device; The power system model objects are converted into nodes. The node labels are the equipment types of the corresponding objects, and the attributes are the attribute values ​​in the CIM / E of the corresponding objects.

[0026] Based on the intrinsic characteristics of the power system model objects, the objects are further divided into conductive equipment and container equipment, and corresponding labels are attached to the corresponding nodes. To reduce the creation of relationships and circular connections, the node numbers in CIM / E need to be materialized into nodes, and the electrical equipment is connected to the nodes with node numbers, forming a "device-node number-device" construction form.

[0027] The physical connection relationship of the conductive equipment nodes forms a static node relationship based on the node number in CIM / E. The busbar and the circuit breaker connected to it have the same node number. Similarly, the circuit breakers also have the same node number. The connection relationship must be established in the graph database.

[0028] The "device-node number-device" construction format will prevent the situation where three or more devices are connected to one node number and the above devices are cross-connected with each other, thus avoiding as much as possible the ring connection that does not actually exist.

[0029] Dynamic topology connection methods are: B1. Delete the dynamic connection of the opening switch and create a dynamic connection of the closing switch according to the switch remote signaling status; B2. Distinguish static and dynamic topological relationships in the same graph by superimposing labels.

[0030] The graph database model design for dynamic topology retains the elements of existing nodes and relationships, and superimposes relationships of new label types on this basis. That is, on the existing static topology graph, a relationship with a new label that is different from the static physical connection label and represents the dynamic topology connection is created.

[0031] The logic for building dynamic topology relationships is as follows: Introducing the real-time switch telesignaling status of the power system; By default, dynamic topology connections are established on all static topology connections; Monitor and analyze the real-time telesignaling status of the switch. According to the on / off status of the switch equipment, delete the dynamic topological connection between the switch equipment node in the off state and the node number node connected to its static topology, and create a dynamic topological connection between the switch equipment node in the on state and the node number node connected to its static topology.

[0032] The advantage of this creation method is that the connection status of static and dynamic topologies can be superimposed on a single diagram, which reduces the creation of model nodes and allows electrical island connectivity analysis with different rules to be superimposed on a single diagram.

[0033] A2. Combining the force-oriented algorithm, orthogonal layout algorithm and hierarchical layout algorithm, the connection wiring diagram between master stations is automatically generated to show the complex connection paths between distribution network equipment.

[0034] In the step A2: The force-directed algorithm iteratively optimizes the layout by simulating the attractive and repulsive forces between nodes.

[0035] The force-directed algorithm determines the position of nodes and the direction of edges by simulating the forces and repulsions between nodes. That is, the shorter the connection between nodes, the greater the repulsion between them; the longer the connection between nodes, the greater the attraction between them. By continuously calculating the balance of forces, a network diagram with reasonable node positions and beautiful edge layout is eventually obtained.

[0036] The final node position and edge direction are obtained through continuous iteration, including the following steps: Initialization: First, randomly generate an initial position for each node and calculate the distance between each node.

[0037] Calculate force: For each node, calculate the force and repulsion between it and other nodes. The force between nodes is expressed as the sum of attraction and repulsion, that is: ; Gravity represents the attractive force between nodes and is usually calculated using Hooke's law, which is: = ; in, is the spring constant, For nodes and nodes The distance between them.

[0038] Repulsion refers to the repulsive force between nodes and is usually calculated using Coulomb's law, that is: = ; in, is the coefficient of repulsion.

[0039] Update position: Update the position of each node based on the force calculated in the previous step. Specifically, I calculate the net force on each node, and then calculate the acceleration of the node based on Newton's second law. Through continuous iteration, I finally get the final position of each node.

[0040] Iteration: The above steps need to be iterated continuously until the position of the node reaches an equilibrium state or the specified number of iterations is reached.

[0041] The orthogonal layout algorithm ensures that edges do not cross and nodes are hierarchically aligned.

[0042] The orthogonal layout algorithm is used to graphically display hierarchical data, such as tree structures. The core principles are to avoid generating crossed edges, maintain overall symmetry, distribute nodes and edges as evenly as possible, and keep edge lengths as uniform as possible to ensure visual clarity and aesthetics. The following principles are involved: (1) The edges of the tree should not cross each other: This is the basic principle to ensure the orthogonality of the layout, that is, to ensure that the connection lines between nodes do not cross each other, thus avoiding visual confusion; (2) All nodes of the same depth are drawn on the same horizontal line: This principle helps maintain the hierarchy of the layout, so that nodes at the same level form a clear visual hierarchy; (3) Tree nodes at the same level should have a certain amount of space between them: this helps to distinguish different nodes, avoid overcrowding, and improve the readability of the layout; (3) Parent nodes should focus on child nodes: This principle helps to form a clear parent-child relationship, making the entire tree structure more intuitive and easy to understand.

[0043] It aims to effectively display complex tree structures or other similar data structures in two-dimensional or multi-dimensional space through non-crossing connecting lines and clear hierarchical structure.

[0044] The hierarchical layout algorithm reduces edge crossings and maintains the hierarchical structure.

[0045] The hierarchical layout algorithm arranges the nodes in the graph according to a certain hierarchical structure to make the connections between the nodes clearer. The steps to generate the graph based on the graph data are as follows: The layout of nodes is hierarchical; The number of edge intersections is as small as possible; The path of the edge can be a straight line as much as possible; The path of the edge is as short as possible; The layout is as balanced as possible; The nodes of each layer are placed on the same horizontal line and do not overlap; Each edge is drawn with a straight line.

[0046] The algorithm implementation process based on the above conditions is node layering, reducing node intersections, adjusting and recalculating nodes, and forming a graph. Figure 5 shown.

[0047] During the generation of the inter-master station connection diagram, the user is allowed to specify node alignment and grouping constraints, and node overlap is avoided by automatically generating layout constraints. The layout algorithm of this project is implemented by combining the above several algorithms. Its features include: achieving higher-quality layout; being more stable in interactive applications; allowing the user to specify constraints such as alignment and grouping; automatically generating constraints to avoid node overlap; and providing a flow layout for directed graphs. It may not be scalable to very large graphs.

[0048] A3. Automatically generate a large-scale power outage transfer plan based on busbar status, interconnection paths, and line margins, including power supply line selection, load priority calculation, and dynamic adjustment strategies.

[0049] In step A3, the calculation formula of the line margin is: -OC-C ; in, is the upper limit of the outgoing switch current at the opposite end, is the load factor, OC is the current value of the outgoing line switch at the opposite end, C The current value of the outgoing switch at this end; when When ≥0, it is determined to be a power supply line.

[0050] Obtain a list of buses in the substation and count the outgoing line switches under the bus. If the bus tie switch between two buses is in the closed state, any bus can be used to supply the other bus.

[0051] The main distribution network equipment is modeled by the connection point number and the triplet Describe the graph model.

[0052] in, = , is a non-empty finite set of nodes, in The element is called nodes.

[0053] = , is the vertex set Ordered node pairs in The set of relations that in The element is called relationship, and satisfy .

[0054] It is a collection of node attributes and relationship attributes.

[0055] Through the topological analysis of the graph model, the communication path between the outgoing line switch under the bus and the outgoing line switch at the opposite end is obtained.

[0056] According to the communication path, the distribution network primary switch of the outgoing line switch is analyzed and it is determined whether the primary switch is a three-remote switch.

[0057] Combined with the tie switch and primary switch type of the outgoing switch, the outgoing switch is classified as follows: No contact switch; The contact switch is not three-remote; The first switch is not a three-way remote control or there is no first switch; The first switch is three-remote and the contact switch is three-remote.

[0058] Subsequently, the appropriate belt supply method is selected according to different types.

[0059] In step A3, the dynamic adjustment strategy includes the following steps: D1. Accumulate the load values ​​of the supplied lines in order of priority. If the total load exceeds the margin, the lines without interconnection and the lines without the first switch and three remote control are kept first; D2. Optimize the supply plan by shedding load, supplying to the opposite end, or actively supplying; Among them, the current value set of the line without tie switch is recorded as ; The first switch is not a three-way remote control or there is no first switch, and the current value set is recorded as ; The tie switch is not a three-way remote control, and the current value set is recorded as ; The first switch is three-remote and the tie switch is three-remote, the current value set is recorded as .

[0060] Calculation logic: According to the priority of the line to be supplied, the current values ​​of the line outgoing switches are accumulated in sequence to calculate whether it can be supplied by the designated supply line.

[0061] like + + + ≤ , then the alternative line can carry all the loads under the busbar; like + + + > , then the lines without tie switches and the lines without first switches but not three remote switches need to be supplied by busbars, that is, they need to meet + ≤ ; If the conditions are still not met, try to shed the load by switching on the power supply line; If load shedding attempts still fail to meet the supply conditions, it is necessary to specify the line ( ) Loss of load.

[0062] Contact switch non-three remote control ( ) and the first switch is three-remote and the tie switch is three-remote ( ) can be partially supplied by the other end, such as Figure 6 shown.

[0063] Since the margin of the supply line cannot meet the load of the supply bus, we can try to transfer part of the load of the opposite line of the supply line through the connecting line of its opposite line to the supply line, release the margin of the opposite line, and thus increase the margin of the supply line to meet the current supply demand.

[0064] For lines that cannot be restored through busbar supply, the opposite end line can be used for supply. Since there may be multiple opposite end contact lines, the selection of the opposite end line should follow the following principles: The line margin at the opposite end meets the supply demand; Priority shall be given to lines with three remote control interconnecting switches.

[0065] The steps of actively supplying include: E1. Select busbar A with external connection, and supply busbar B without external connection through its outgoing switch S1; E2. Open the S1 switch or the first switch, and the other end of the S1 line will supply bus B, and the other outgoing switch S2 of bus A will supply bus A.

[0066] If the busbars are only connected by an off-site interconnection circuit, and there is a busbar without external connection (denoted as B), you can try to actively supply power through the busbar with external connection (denoted as A).

[0067] The specific measures are as follows: like Figure 7-8 As shown, select the outgoing switch S1 under bus A that meets the conditions for power supply. This switch is connected to the outgoing switch K1 of bus B through an off-station loop. Pull open the S1 switch or the first switch under the S1 switch, and the B bus will be supplied with power from the opposite end of the S1 line. Then, the S2 switch under bus A that meets the conditions for power supply will supply the A bus, thus completing the power supply solution.

[0068] In summary, by combining the distribution network topology and the communication between the main stations, the research proposes a method for automatically compiling power supply plans, including power transfer when the upper power supply fails and the bus is operational, bus failure transfer, bus maintenance transfer, and main transformer overload transfer, which can quickly and efficiently generate power transfer plans.

[0069] A4. The power transfer plan is executed in real time through a visual interactive interface, which supports dispatchers to operate item by item or jump items, and simultaneously displays the changes in the power supply path and the power supply status.

[0070] In step A4, the visual interactive interface is developed based on the Java Swing framework, using the MVC model to separate the data model and the view; Design principles include: The interface follows the principles of simplicity, clarity, consistency, focus, and interactivity; Displays changes in power supply range and load transfer paths after switch operations in real time.

[0071] The functions of the visual interactive interface include: The power transfer operation can be executed item by item or by skipping items. The implementation of the plan should be divided into two types: item by item and skipping items. For the actual control process of power transfer, the dispatcher should have a certain degree of freedom when using the system based on the on-site situation. For problems that may arise in on-site switches, the dispatcher can interactively skip the order of the plan list, execute a certain combination of items separately, and continue to execute downwards; Automatically trigger the regeneration of the power transfer plan when an operation fails. During the actual control of the plan, a certain combination switch operation may fail. For such operations, the power transfer plan should be regenerated during the execution process; Color markings and dynamic graphics are used to highlight key power supply status. During the actual control of the plan, when the dispatcher operates relevant combination items, the power supply communication diagram displayed on the interactive interface will simultaneously show the switch operation process and the changes in power supply status after the switch operation.

[0072] The actual control interface of this project was developed in Java language with comprehensive consideration of cost scale and ease of use, mainly using the swing class library.

[0073] The actual control interface of this embodiment is developed in Java language with comprehensive consideration of cost scale and ease of use, mainly using the class library Swing. Through the event mechanism and pluggable sensory characteristics of the Swing class, and by using custom models, it can achieve high adaptability and meet user needs while avoiding unnecessary data requests. Java Swing has more advantages than other Java interface components.

[0074] The commonly used design patterns in Java are mainly MVC pattern and master control pattern.

[0075] MVC is a design pattern that uses MVC to divide applications into three core components: model, view, and controller, and each of them handles its own tasks. The model represents enterprise data and business rules. Among the three components of MVC, the model has the most processing tasks. The data returned by the model is neutral, which means that the model has nothing to do with the data format. Such a model can provide data for multiple views. Since the code applied to the model only needs to be written once and can be reused by multiple views, the duplication of code is reduced.

[0076] The master control pattern is a master control function (file) that calls other functions (files) and objects. A master control function calls function 1 and function 2, which in turn calls objects 1, 2, and 3. This pattern emphasizes object-locating entry points and method integration. Because all functions and objects in the pattern are called through the master control function, the master control pattern allows for loose coupling between objects, centralized method location, and strong scalability.

[0077] The swing architecture is basically based on the Model-View-Controller (MVC) design template, and its data is independent of the expression and processing of data.

[0078] The architectural features of the swing class include: detachable model architecture and pluggable sensor architecture.

[0079] The separable model architecture is characterized by the fact that the model has no intrinsic connection with the view that represents it (this practice of correlation is criticized when multiple views use the same model). The model only has some event listeners that are interested in changes to its state. A Swing component is responsible for hooking up its associated model listeners so that it can accurately redraw itself when the model changes, whether using the default internal model or the model implemented by the application.

[0080] The so-called pluggable sensory architecture means that the swing architecture allows us to use a single component API without specifying a specific sensory. The swing toolkit provides a set of default sensors, and the API is "open". This design allows developers to inherit existing sensors to create new sensors or create a new set of sensors from scratch.

[0081] Although the pluggable sense API architecture is extensible, it is designed at the lower level of the basic component API, so that developers do not need to understand all its details when developing swing GUI. In general, the pluggable sense design means that the implementation of the component's presentation (appearance) and event handling (feel) parts is delegated to independent ui objects of the currently installed senses that can be replaced at any time during runtime. Pluggable senses include some small hooks of the swing component class, some top-level APIs for sense management, and more complex APIs that actually implement senses in independent packages.

[0082] Swing's models are divided into two types: GUI state model and application data model. The GUI state model is an interface that defines the visual state of a GUI controller, such as whether a button is pressed or released, or whether items in a list are selected. The GUI state model is often related to the context of the graphical user interface (GUI).

[0083] The state of the GUI controller can be manipulated through the top-level methods of the component without having to interact directly with the model. In the table described above, the swing GUI state model is highlighted in green.

[0084] The events MouseEvent and KeyEvent in Swing handle interrupt events generated by computer input and output devices, such as the interaction between the mouse and keyboard and the GUI system. In Swing, events are added to the system event queue through methods such as postEvent, repaint, and invokeLmer to trigger program events.

[0085] In the distribution network topology model, the power supply range analysis step includes: F1. Extract the distribution network label subgraph and calculate the weakly connected components to divide the electrical islands. F2. Combine path search and bidirectional detection to determine the set of power-off devices downstream of the switch.

[0086] Based on the actual physical connections of the power grid and the on / off positions of switches, the distribution network can be divided into several connected subgraphs. The implementation strategy is to use the connectivity analysis and calculation method of GDS graph science. The specific implementation steps are as follows: Initialize the distribution network label and assign distribution network labels to all distribution network conductive device nodes and node number nodes.

[0087] Memory subgraph extraction uses the GDS graph projection function to create a projection to the memory subgraph based on the distribution network labels and dynamic topology connection relationships.

[0088] Connected component calculation, using GDS graph weakly connected component calculation, so that each node obtains its corresponding connected component ID, and rewrites the graph library from the memory graph.

[0089] When a distribution network switch trips, dispatchers and power supply service commanders are concerned about the impact of the switch on the downstream power outage range, so it is very important to quickly and accurately locate the power outage range.

[0090] Using Ceo4j's path search for bidirectional detection can quickly locate the downstream direction and downstream range of the switch.

[0091] The Neo4j-based downstream analysis strategy for power supply of distribution network equipment is as follows: Obtain the node numbers at both ends of the conductive device. Query whether a dynamic path exists from each node number to the main bus device. If both nodes exist, the device is in a ring network state. The device has no downstream nodes: If neither node exists, the device is in an island state. It has no upstream nodes: If one node number can find the main bus device, the other node number is the downstream node number.

[0092] According to the downstream node number, use Cyber ​​statement path search to search for all dynamically connected devices downstream.

[0093] The operation of the power grid is complex. By combining the current graph database technology to calculate the load transfer path of the main distribution network, designing the full shutdown transfer method of the substation, and conducting in-depth analysis and research on the optimal load transfer path of the distribution network, its significance is mainly reflected in the following aspects: economic benefits, distribution network load transfer path analysis, by reducing manual intervention and reducing operational errors, effectively reducing the cost of power grid operation and maintenance, improving the reliability and stability of the power grid, reducing potential power losses, and improving the operation efficiency of the power grid, management benefits, through distribution network load transfer path analysis, reducing the need for manual intervention, reducing the risk of human error, and improving the manageability and controllability of power grid operation, enabling dispatchers to obtain the required information more quickly, helping dispatchers to focus more on key decisions, social benefits, through the analysis of distribution network load transfer path, helping to ensure the availability of power supply, reducing the impact of power outages on social life and economic activities, reducing the impact of power supply interruptions on enterprises and families, and promoting social sustainable development.

[0094] The above-mentioned front, back, left, right, up and down are all based on the Figure 1 As a benchmark, according to the person's observation perspective, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0095] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention.

[0096] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A distribution network reconstruction method, characterized by: The following steps are involved: A1. Build a distribution network topology model based on a graph database, convert power equipment into nodes, establish static connection relationships according to CIM / E standards, and overlay dynamic topology connections based on real-time switch status; A2. Combining the force-oriented algorithm, orthogonal layout algorithm, and hierarchical layout algorithm, it automatically generates a connection diagram between master stations, showing the complex connection paths between distribution network equipment. A3. Automatically generate a large-scale power outage transfer plan based on busbar status, interconnection paths, and line margins, including power supply line selection, load priority calculation, and dynamic adjustment strategies; A4. The power transfer plan is executed in real time through a visual interactive interface, which supports dispatchers to operate item by item or jump items, and simultaneously displays the changes in the power supply path and the power supply status.

2. A distribution network reconstruction method according to claim 1, characterized in that: In step A1, the static connection relationship is established in the following manner: Device to node number to device; The dynamic topology connection method is: According to the switch telesignaling status, delete the dynamic connection of the opening switch and create the dynamic connection of the closing switch; Distinguish static and dynamic topological relationships in the same graph by overlaying labels.

3. A distribution network reconstruction method according to claim 1, characterized in that: In the step A2: The force-directed algorithm iteratively optimizes the layout by simulating the attractive and repulsive forces between nodes; The orthogonal layout algorithm ensures that edges do not cross and nodes are hierarchically aligned; The hierarchical layout algorithm reduces edge crossings and maintains the hierarchical structure.

4. A distribution network reconstruction method according to claim 1, characterized in that: In step A3, the calculation formula of the line margin is: -OC-C ； in, is the upper limit of the outgoing switch current at the opposite end, is the load factor, OC is the current value of the outgoing line switch at the opposite end, C The current value of the outgoing switch at this end; when When ≥0, it is determined to be a power supply line.

5. A distribution network reconstruction method according to claim 1, characterized in that: In step A3, the dynamic adjustment strategy includes the following steps: D1. Accumulate the load values ​​of the supplied lines in order of priority. If the total load exceeds the margin, the lines without interconnection and the lines without the first switch and three remote control are kept first; D2. Optimize the supply plan by shedding load, supplying to the opposite end, or actively supplying; Among them, the current value set of the line without tie switch is recorded as ; The first switch is not a three-way remote control or there is no first switch, and the current value set is recorded as ; The tie switch is not a three-way remote control, and the current value set is recorded as ; The first switch is three-remote and the tie switch is three-remote, the current value set is recorded as .

6. A distribution network reconstruction method according to claim 5, characterized in that: The steps of actively supplying include: E1. Select busbar A with external connection, and supply busbar B without external connection through its outgoing switch S1; E2. Open the S1 switch or the first switch, and the other end of the S1 line will supply bus B, and the other outgoing switch S2 of bus A will supply bus A.

7. A distribution network reconstruction method according to claim 1, characterized in that: In step A4, the visual interactive interface is developed based on the Java Swing framework, using the MVC model to separate the data model and the view; Design principles include: The interface follows the principles of simplicity, clarity, consistency, focus, and interactivity; Displays changes in power supply range and load transfer paths after switch operations in real time.

8. A distribution network reconstruction method according to claim 7, characterized in that: The functions of the visual interactive interface include: Execute the transfer operation item by item or skip items; Automatically trigger the regeneration of the transfer plan when the operation fails; Color coding and dynamic graphics highlight key power status.

9. A distribution network reconstruction method according to claim 1, characterized in that: In the distribution network topology model, the power supply range analysis step includes: F1. Extract the distribution network label subgraph and calculate the weakly connected components to divide the electrical islands. F2. Combine path search and bidirectional detection to determine the set of power-off devices downstream of the switch.

10. A distribution network reconstruction method according to claim 1, characterized in that: During the generation process of the inter-master station connection diagram, the user is allowed to specify node alignment and grouping constraints, and node overlap is avoided by automatically generating layout constraints.

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