Intelligent network connection micro-grid double-bus topology reconstruction and energy supply maintaining method and system

Abstract

The invention discloses an intelligent network connection micro-grid double-bus topology reconstruction and energy supply maintaining method and system, and belongs to the technical field of intelligent network connection road domain micro-grids. The method comprises the following steps: firstly, constructing a double-bus micro-grid structure comprising two groups of direct-current buses and four-position interconnection switches, and determining a plurality of operation modes; then establishing a topology operation rule and electrified logic constraint, a radial and connectivity constraint, a direct current micro-grid power flow constraint and an energy router echelon energy discharge and segmented energy storage management constraint; and finally, by taking maximization of the power supply and protection capability of the key intelligent network connection equipment as a target, establishing an optimization model and solving to obtain a topology reconstruction scheme. According to the method, the problems of insufficient topology flexibility, inaccurate constraint characterization, disordered energy coordination and the like in the prior art are solved, rapid topology reconstruction and high-elasticity energy supply maintenance can be realized under multi-point faults of extreme events, and safe operation of an intelligent network connection traffic system is guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of microgrid operation and control technology, specifically relating to a method and system for intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance. Background Technology

[0002] With the rapid development of intelligent connected roads, road microgrids, as a key power supply infrastructure for intelligent connected devices, are playing an increasingly important role in ensuring traffic management, road safety, and driving experience. Road microgrids integrate energy routers, substation-side rectifiers, photovoltaic power generation units, energy storage systems, and various feeder switches. These devices, through flexible networking integration, provide reliable power supply to intelligent connected devices such as roadside units (RSUs), 5G base stations, lidar, and cameras. However, with the intensification of global climate change and the increasing frequency of extreme weather events, numerous power outages have occurred, posing a severe challenge to the normal operation of road microgrids. In the event of multi-point faults, some busbars or tie switches may be damaged, directly affecting the power supply reliability of intelligent connected devices and thus threatening the safe operation of the traffic system. Therefore, in responding to extreme events, achieving rapid topology reconfiguration and highly resilient power supply maintenance of road microgrids to ensure continuous power supply to critical intelligent connected devices is particularly important. The existing road microgrid management system has the following defects and shortcomings: First, existing road microgrid topologies mostly adopt a single bus configuration, which lacks topological flexibility, and the power supply mainly comes from the municipal power grid or the backup power supply of the substation, resulting in isolated power transmission paths. When a bus or critical switch fails, it is difficult to achieve flexible topological connectivity and coordination, severely limiting the system's emergency power supply capability and failing to meet the high-reliability power supply requirements of intelligent connected roads.

[0003] Second, existing microgrid reconfiguration methods are mainly designed for urban distribution networks and fail to fully consider the special characteristics of the dual-busbar structure of road microgrids. The dual-busbar system of road microgrids has unique fault isolation logic and parallel operation specifications, and the topology and power flow distribution of the buses and tie switches have different physical connotations than those of traditional distribution networks. Existing methods are unable to accurately characterize its operating rules and constraints.

[0004] Third, existing energy routers lack a systematic multi-energy coordination mechanism in their energy management strategies. Energy routers contain various types of ports, including high-entropy energy ports, photovoltaic ports, grid-connected ports, and energy storage ports. Existing methods have failed to establish a reasonable energy utilization sequence and energy storage management strategy, affecting the economic efficiency of normal operation and the continuous power supply capability for emergency backup.

[0005] Fourth, existing microgrid reconfiguration optimization methods fail to fully consider the differences in the functional importance of intelligent connected devices. Given limited emergency power resources, there is a lack of a reconfiguration objective function oriented towards improving the power supply capabilities of critical intelligent connected devices, making it impossible to achieve reasonable allocation and priority scheduling of emergency resources. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a method and system for dual-bus topology reconfiguration and power supply maintenance in intelligent connected microgrids. This method and system solve the technical problems of inflexible topology reconfiguration, slow power supply recovery, low energy utilization efficiency, and insufficient power supply guarantee for critical transportation equipment caused by multi-point failures due to extreme weather and other factors. These problems include a simple and rigid topology structure, a lack of accurate reconfiguration models adapted to the special characteristics of dual buses, an imperfect coordination mechanism for multiple energy ports of energy routers, and insufficient consideration of the functional importance differences of intelligent connected devices in reconfiguration optimization. This invention enables intelligent connected microgrids to have flexible topology reconfiguration and highly elastic power supply maintenance capabilities when facing multi-point failures in extreme events.

[0007] The present invention adopts the following technical solution: A method for dual-bus topology reconfiguration and power supply maintenance in intelligent connected microgrids includes the following steps: A dual-bus microgrid structure including a first DC bus and a second DC bus is constructed, and a four-position tie switch is set between the first DC bus and the second DC bus. The operation mode of the dual-bus microgrid is determined based on the state of the four-position tie switch and the switch state of the mains power supply. Based on the aforementioned dual-bus microgrid structure and operation mode, topology operation rules and live logic constraints of the dual-bus microgrid are established. The constraints are based on mixed integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. Based on the aforementioned topology operation rules and live logic constraints, the concepts of virtual power flow and virtual branch are introduced to establish the radial and connectivity constraints for the operation of the dual-bus microgrid. Based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, and combined with the radial and connectivity constraints, a DC microgrid power flow constraint is established. Establish local energy management policy constraints for the energy router, the policy including the tiered energy release sequence of each energy port of the energy router and the segmented energy management of the energy storage port based on the state of charge; With the goal of maximizing the power supply capability of key functions of intelligent connected devices, an objective function of the reconfiguration optimization model is established, and the solution is obtained based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints.

[0008] Preferably, the grid connection ports of each substation-side rectifier and each energy router distributed along the road are all connected to the first DC bus and the second DC bus via feeders; the first DC bus and the second DC bus are both divided into multiple sections, and each section is connected to the other via the four-position tie switch; the operating modes include grid-connected dual bus operation, grid-connected dual bus mutual support, grid-connected single bus operation, off-grid dual bus operation, off-grid dual bus mutual support, and off-grid single bus operation.

[0009] Preferably, the four-position interconnection switch is used to control the connection state between #A-1 and #B-1, #A-2 and #B-2, #A-1 and #B-2, and #A-2 and #B-1; the switches connected to the mains power include switch #A, switch #B, switch #E1, and switch #E2, each of which includes two sub-switches, S1 and S2. Different operating modes are achieved by coordinating the closed and open states of the sub-switches with the four-position interconnection switch.

[0010] Preferably, the topology operation rules and live logic constraints include live logic constraints, radial topology constraints, and dual-busbar safe operation rules; the distribution network main transformer and rectifier nodes, each bus section and energy router are defined as the node set in the power network, and the branch of the transformer-side rectifier connected to the bus, the tie switch in the bus and the feed branch of the energy router grid connection port are defined as the line set in the power network; The live logic constraints include: the bus or node in a fault must be de-energized; when the bus or power supply is in a fault isolation state, the surrounding tie switches or feeder lines must be disconnected; an unenergized node can be energized through at most one switchable line; a bus node can only be energized after at least one of its surrounding switches is energized; and a switch can only be closed when at least one end is energized. The dual-busbar safe operation rules include calculating and constraining the number of switching actions at each step, and determining whether the energy router is simultaneously connected to two energized buses.

[0011] Preferably, the radial and connectivity constraints are established based on the single-commodity flow theory, including: The total number of energized nodes minus the number of energized lines equals the number of root nodes participating in providing virtual power flow; the virtual power flow balance equation for potential root nodes and other nodes; segmented buses themselves do not have power sources and cannot serve as root nodes; potential root nodes include energy router nodes and mains transformer nodes, and can only serve as root nodes when energized; a node can only provide virtual power flow when it serves as a root node; lines can only flow through virtual power flow when energized.

[0012] Preferably, the power flow constraints of the DC microgrid include: Power balance equations for each feeder node on the busbar; power balance equations for the beginning and end of each busbar; Ohm's law equations for each segment of the busbar, including the resistance per unit length of the busbar; Ohm's law equations for the busbar tie switches, including the contact resistance of the tie switches; Ohm's law equations for the energy router feeders or substation feeders, including the resistance of each feeder and the power flowing through them; power can only flow through closed tie lines; capacity constraints for each feeder / busbar and voltage amplitude constraints for each node; droop control characteristic equations for the grid-connected ports of the energy router.

[0013] Preferably, the ports of the energy router include high-entropy energy ports, photovoltaic ports, grid-connected ports, energy storage ports, and load ports; the local energy management strategy constraints also include the energy router power balance equation and the judgment constraints for each port to reach its maximum discharge power, the judgment constraints being determined based on the comparison results of DC voltage and adjustment threshold of each port.

[0014] Preferably, the tiered energy release sequence is determined by monitoring the DC capacitor voltage of the energy router. As the DC voltage gradually decreases, the energy is discharged in the following order: high-entropy energy port, photovoltaic port, grid-connected port, and energy storage port. The segmented energy management of the energy storage port based on the state of charge specifically involves: When the state of charge is below the low threshold, discharge is reduced; when the state of charge is between the low and high thresholds, direct droop control is used; when the state of charge is above the high threshold, discharge is accelerated.

[0015] Preferably, the objective function includes a weighted term for the importance index of the load on each energy router, a penalty term related to the number of switching operations, a penalty term related to the simultaneous connection of two ports of the energy router to the bus, and a penalty term related to the tie switch that connects the first DC bus and the second DC bus.

[0016] Secondly, embodiments of the present invention provide an intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance system, comprising: The operation module is used to construct a dual-bus microgrid structure including a first DC bus and a second DC bus. A four-position tie switch is set between the first DC bus and the second DC bus. Based on the state of the four-position tie switch and the switch state of the mains power supply, the operation mode of the dual-bus microgrid is determined. The topology module is used to establish the topology operation rules and live logic constraints of the dual-bus microgrid based on the structure and operation mode of the dual-bus microgrid. The constraints are based on mixed integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. The radial module is used to introduce the concepts of virtual power flow and virtual branches based on the topology operation rules and energized logic constraints, and to establish the radial and connectivity constraints of the dual-bus microgrid operation. The power flow module is used to establish DC microgrid power flow constraints based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, combined with the radial and connectivity constraints. An energy module is used to establish local energy management policy constraints for the energy router. The policy includes the tiered energy release sequence of each energy port of the energy router and the segmented energy management of the energy storage port based on the state of charge. The solution module is used to establish the objective function of the reconfiguration optimization model with the goal of maximizing the power supply capability of key functions of intelligent connected devices, and to solve the topology reconfiguration scheme based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints.

[0017] Thirdly, a computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method.

[0018] Fourthly, embodiments of the present invention provide a computer-readable storage medium including a computer program, which, when executed by a processor, implements the steps of the above-described intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method.

[0019] Fifthly, a chip includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method.

[0020] In a sixth aspect, embodiments of the present invention provide an electronic device, including a computer program, which, when executed by the electronic device, implements the steps of the above-described intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method.

[0021] Compared with the prior art, the present invention has at least the following beneficial effects: A method for topology reconfiguration and power supply maintenance in intelligent connected microgrids with dual buses is proposed. First, through an innovative dual-bus structure and four-position tie switch design, flexible and rapid switching between various operating modes, such as grid-connected / off-grid, dual-bus / single-bus, and mutual / independent operation, is achieved, greatly improving the adaptability and reconfiguration capability of the topology. Second, a complete mixed-integer optimization modeling system is proposed, specifically tailored to the characteristics of dual-bus systems. This system accurately characterizes fault isolation logic, radial and connectivity constraints, segmented power flow distribution, and multi-energy coordination strategies, providing a solid theoretical model for quickly and safely solving for the optimal reconfiguration scheme. Finally, the functional importance of intelligent connected devices is incorporated into the optimization objective, ensuring the continuous power supply of critical equipment under conditions of limited emergency resources. This invention significantly enhances the resilience and survivability of road microgrids in the face of multi-point faults, providing key technical support for the safe and reliable operation of intelligent connected transportation systems.

[0022] Furthermore, by connecting the substation-side rectifier and energy router grid connection ports to two sets of DC buses, and with the bus segments connected via four-position tie switches, the limitation of isolated power transmission paths on a single bus is broken. Six operating modes can be flexibly switched according to the grid connection status and fault conditions, such as grid-connected dual-bus mutual support and off-grid dual-bus operation, adapting to power supply needs under different fault scenarios. When a bus segment or switch fails, load transfer and power supply mutual support can be quickly achieved by switching operating modes, significantly improving the microgrid's emergency response capability and power supply reliability, meeting the high requirements of continuous power supply for intelligent connected roads.

[0023] Furthermore, the four-position tie switch can specifically control the connection status between the four busbars. Combined with the mains access switch group containing twin sub-switches, the accurate implementation of six operating modes is ensured through the coordination of the sub-switches and tie switches. This design avoids the problem of operating mode switching failure caused by ambiguity in switch control logic, making the switching of the dual-bus microgrid more precise and efficient in different scenarios such as grid-connected / off-grid and single-bus / dual-bus configurations. It provides reliable hardware control support for rapid topology adjustment in case of faults, improving the stability and controllability of system operation.

[0024] Furthermore, by clearly defining the sets of nodes and lines, and refining the energized logic constraints and dual-bus safety operation rules, such as power outages at faulty nodes and constraints on the number of switch actions, this system accurately characterizes the unique fault isolation logic and parallel operation specifications of the dual-bus system. Compared to traditional distribution network reconfiguration methods, this constraint system fully considers the physical differences between the microgrid buses and tie switches, avoiding the problems of unsafe and infeasible reconfiguration schemes caused by inaccurate constraint characterization. It ensures the speed of fault isolation and the safety of dual-bus operation, providing a scientific constraint boundary for topology reconfiguration.

[0025] Furthermore, by introducing the concepts of virtual power flow and virtual branches, two buses in the same section are included in the radial constraint considerations, effectively avoiding the ring network problem and fault propagation risk that may occur in dual-bus operation. Various constraints, from the definition of root nodes and virtual power flow balancing, ensure the rationality of the network topology from multiple dimensions, ensuring that key requirements such as substation nodes not sharing the network and segmented buses not acting as root nodes are implemented. This design solves the problem that existing reconfiguration methods are difficult to adapt to the connectivity control of dual-bus topologies, improves the stability and security of topology reconfiguration, and lays a reliable foundation for the establishment of subsequent power flow constraints.

[0026] Furthermore, the constraint system encompasses multiple dimensions, including power balance, Ohm's law, capacity-voltage, and droop control. It fully considers the structural characteristics of segmented busbar feeds and cross-interconnections, establishing constraints separately for each busbar segment, tie switch, and feeder. Compared to traditional power flow constraints, this system better aligns with the operating characteristics of a dual-bus microgrid, accurately calculating the voltage and power flow distribution at each node and preventing equipment damage or power outages due to power flow imbalances. This constraint ensures the stability and economy of the microgrid's electrical operation after topology reconfiguration, providing crucial electrical safety assurance for power supply maintenance.

[0027] Furthermore, the energy router is defined to include five types of ports. By establishing a power balance equation and determining the maximum discharge power of each port, orderly coordination of multiple energy ports is achieved. The determination constraint is based on the comparison between DC voltage and adjustment threshold. No direct communication between ports is required. Orderly control of energy utilization can be achieved solely through local measurement data, solving the problem of chaotic multi-energy coordination in existing technologies.

[0028] Furthermore, the tiered energy release system monitors the DC capacitor voltage and discharges in the order of high-entropy energy, photovoltaics, grid connection, and energy storage, prioritizing the use of renewable energy and grid power to reduce energy storage consumption. Segmented energy storage management adjusts the energy release strategy based on the state of charge, effectively mitigating overcharging and over-discharging and extending the lifespan of energy storage equipment. This design addresses the lack of systematic approach and insufficient emergency power supply capacity in existing energy management strategies. While ensuring power supply to critical equipment, it also considers operational economy and equipment durability, improving the long-term stable operation capability of the microgrid.

[0029] Furthermore, by using a load importance weighting factor, priority is given to ensuring power supply to critical smart connected devices; three types of penalty factors are set to reduce the complexity of switch operation, resonance risk, and the frequency of use of cross-group bus tie switches, respectively. This specifically addresses the problems of existing reconfiguration methods that do not consider differences in equipment importance and unreasonable resource allocation.

[0030] It is understood that the beneficial effects of the second to sixth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0031] In summary, the method of this invention provides strong technical support and theoretical basis for rapid fault isolation, topology reconstruction, and high-elasticity power supply maintenance of intelligent connected road microgrids under extreme events through flexible dual-bus topology design, scientific mixed-integer optimization modeling, reasonable energy management strategies, and equipment importance-oriented optimization objectives. This helps to improve the safety and reliability of intelligent connected transportation systems.

[0032] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0033] Figure 1 Topology diagram of dual DC bus microgrid network integration method; Figure 2 A schematic diagram of node voltage and power flow distribution on the busbar. Figure 3 This is a diagram illustrating the energy utilization sequence of each port on the energy router. Figure 4 Topology diagram of a dual-bus microgrid cluster in a smart connected urban road demonstration area in Tianjin; Figure 5 A schematic diagram of a computer device provided in an embodiment of the present invention; Figure 6 This is a block diagram of a chip according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the method flow of the present invention.

[0034] Among them, 60. Computer equipment; 61. Processor; 62. Memory; 63. Computer program; 600. Electronic device; 610. Processing unit; 620. Storage unit; 6201. Random access memory unit; 6202. Cache memory unit; 6203. Read-only memory unit; 6204. Program / utility; 6205. Program module; 630. Bus; 640. Display unit; 650. Input / output interface; 660. Network adapter; 700. External device. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] In the description of this invention, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0037] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0038] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this invention generally indicates that the preceding and following objects have an "or" relationship.

[0039] It should be understood that although terms such as first, second, third, etc., may be used in the embodiments of the present invention to describe the preset range, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0040] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0041] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0042] This invention provides a method for topology reconfiguration and power supply maintenance of intelligent connected microgrids with dual bus topologies. It employs a dual DC bus structure to achieve flexible network integration and uses a four-position tie switch to switch between multiple operating modes. A topology operation rule and live logic constraint model based on mixed-integer linear programming are established to accurately characterize the fault isolation logic and parallel operation specifications of the dual-bus system. A tiered energy release strategy for each port of the energy router and a segmented energy management strategy for the energy storage port based on DC capacitor voltage monitoring are proposed. A reconfiguration optimization model is established with the primary goal of improving the power supply capability of key functions of intelligent connected devices, providing important technical support for emergency management and highly resilient power supply maintenance of road microgrids.

[0043] Please see Figure 7 The present invention discloses a method for dual-bus topology reconfiguration and power supply maintenance of a smart connected microgrid, comprising the following steps: S1. Design the structure of the double busbar microgrid and the four-position tie switch, and classify the operation mode of the double busbar microgrid according to the position of the tie switch and the position of the switch connected to the mains power. In roadside microgrids, flexible networking and integration of energy routers, substation-side rectifiers, and various feeder switches are required, ensuring the system maintains flexible topology connectivity and collaborative support capabilities in the event of multi-point failures during extreme events. This invention employs a dual-bus structure to flexibly adjust the system topology and operating mode. The system mainly includes two sets of DC buses, and the grid-connected ports of each substation-side rectifier and energy router distributed along the road can be connected to these two sets of DC buses via feeders. The DC buses can be divided into several segments, each connected by a four-position tie switch, enabling switching between various networking modes such as grid-connected dual-bus operation, grid-connected dual-bus mutual support, grid-connected single-bus operation, off-grid dual-bus operation, off-grid dual-bus mutual support, and off-grid single-bus operation.

[0044] Please see Figure 1 It includes two sets of DC buses. The grid connection ports of each substation side rectifier and each energy router distributed along the road can be connected to these two sets of DC buses through feeders. The DC buses can be divided into several sections, and each section is connected by a four-position tie switch to realize the control of the connectivity between #A-1 and #B-1; #A-2 and #B-2; #A-1 and #B-2; and #A-2 and #B-1 respectively.

[0045] The networking methods implemented using dual buses are shown in Table 1: Table 1. Description of Dual Busbar Networking Methods

[0046] S2. Based on the fault isolation logic and parallel operation specifications of tie switches and buses in a dual-bus microgrid, the topology operation rules and live logic constraints are established using a mixed integer optimization modeling method. After a fault damages certain buses or tie switches, switching and power transfer measures can be implemented quickly to achieve rapid topology reconfiguration of the dual-bus microgrid. To quickly obtain the reconfigured topology, a mixed-integer linear programming model is established to represent network topology constraints and dual-bus operation rule constraints. The constraint establishment must consider that the dual-bus system has unique fault isolation logic and parallel operation specifications, and that elements such as nodes and branches have physical characteristics different from those of a distribution network. The distribution network model mainly includes bus nodes and lines. Switches located on a line segment can control the connection and disconnection of the line. In a dual-bus system, the main components are the bus and tie switches. In this case, tie lines connecting rectifiers and energy routers to the grid can be integrated on the bus. Its topology can be abstracted as the characteristics of a node. The tie switches control the connection and disconnection between the two buses, functioning as a line. However, in terms of power flow distribution, a bus distributed along a traffic road is a line with a relatively long span. The merging nodes of various energy routers are located at different positions, and each point on the bus has different power flow and voltage amplitudes. The tie switches mainly function to control topology connectivity and do not possess significant impedance or voltage drop along the line. Therefore, when defining the topology operation rules and live logic constraints of the bus, it can be considered as a node, while when defining the power flow constraints of the lines, the differences in power flow distribution across different segments must be considered.

[0047] The operating rules for dual busbars mainly include live logic constraints, radial topology constraints, and dual busbar safety operating rules. When defining variables, the distribution network main transformer and rectifier nodes are included. Each section of busbar Energy Router Viewed as a set of nodes in a power network Define the branch of the transformer-side rectifier connected to the bus. The tie switch in the busbar And the power router's network connection port Feeding branches are the set of lines in a power network. : Equations (1) and (2) indicate that the bus or node in the fault needs to be de-energized; (1) (2) Equation (3) indicates that when a busbar or power source is in a fault isolation state, the surrounding tie switches or feeder lines must be disconnected; (3) in, and The binary variables representing the energized state of the line and node are respectively, and when they are equal to 1, they represent the energized state of the line / node, respectively, as shown in equations (1) to (3). and A binary variable indicating whether a node or line is in a fault isolation or maintenance state; a value of 1 indicates that it is in a fault isolation state.

[0048] Equation (4) ensures that if a node is not energized in the previous step, it can only be energized through one switchable line at most; (4) Equation (5) indicates that for a busbar node, it can only be energized after at least one switch around it is energized; (5) Equation (6) indicates that a switch can only be closed when at least one end of it is energized; (6) Equations (7) and (8) are used to calculate and constrain the number of switching actions in each step; (7) (8) The absolute value constraint in equation (8) can be achieved by introducing an auxiliary binary variable. Linearization is as follows:

[0049] In equations (9) and (10) This is a binary variable used to indicate whether an energy router is connected to two live buses simultaneously. A value of 1 indicates a node... i Energy router in t Two energized busbars were connected at the same time. 。

[0050] (9) (10) S3. Introduce virtual power flow constraints and propose the concept of virtual branches between two buses on the same segment to establish radial and connectivity constraints for the operation of dual-bus microgrids. To ensure that two substation nodes do not appear in the same network and that no loops exist within the network, a radial constraint is established for the topology using graph theory, such as maximum density, and virtual power flows are defined on each edge. Furthermore, considering that dual-bus operation should minimize the spread of faults, two buses on the same section should ideally not operate in the same microgrid. Virtual branches are used to connect the two buses on the same section, and these are also included in the calculation of the radial constraint. If a virtual branch is closed, the two buses it connects will not be connected to the same microgrid via actual branches, otherwise a loop would be formed; however, virtual branches should not carry actual power flows and do not need to satisfy Ohm's law for branches.

[0051] The radial and connectivity constraints established based on the single-item flow theory in this scenario are as follows: Constraint (11) represents a radial condition where the total number of charged nodes minus the number of charged lines equals the number of root nodes participating in providing virtual power flow; (11) Constraints (12) and (13) represent the virtual power flow equilibrium equations for the potential root node and the remaining nodes, respectively. (12) (13) Constraint (14) indicates that the segmented busbar itself does not have a power source and cannot be used as a root node; (14) Constraint (15) indicates that potential root nodes include energy router nodes and mains transformer nodes, and can only be root nodes when they are energized; (15) Constraint (16) indicates that a node can only provide virtual power flow when it is the root node; (16) Constraint (17) indicates that the virtual power flow can only occur through the line when it is energized.

[0052] (17) Of the above constraints, This represents the virtual power of each power source. This is a binary variable indicating whether the power source is a root node and participates in providing virtual power. A value of 1 indicates that the node can provide virtual power. and Indicates the route through which the water flows and The virtual power.

[0053] This invention establishes radial and connectivity constraints based on single-goods flow theory, including: radial condition constraints, i.e., the total number of energized nodes minus the number of energized lines equals the number of root nodes participating in providing virtual power flow; virtual power flow balance equations for potential root nodes and other nodes; constraints that segmented buses cannot serve as root nodes because they do not have their own power source; constraints that potential root nodes include energy router nodes and mains transformer nodes and can only serve as root nodes when energized; constraints that nodes can only provide virtual power flow when they serve as root nodes; and constraints that lines can only flow through virtual power flow when energized.

[0054] S4. Based on the segmented feed and cross-interconnection characteristics of the dual-bus DC microgrid, the power flow constraints of the DC microgrid are established using the mixed integer linear optimization modeling method. When constructing a dual-bus network, the power flow constraints need to be satisfied, and the power flow needs to be calculated separately for each feeder connection node and each feeder segment on the bus.

[0055] First, number each busbar segment. The busbar contains When there are multiple feed lines, the busbar is divided into A segment, including its two ends, has a total of The node is defined. Power flow vectors involved in the busbar ,in and The first The voltage relaxation variables at the beginning and end of the bus are equal to the square of the DC voltage amplitude; and the power vector of each segment on the bus is defined. The reference direction is from the beginning to the end of the busbar. The power flow and node voltages for each segment of the busbar are labeled as follows: Figure 2 As shown.

[0056] At the same time, the communication switches of each microgrid need to be pre-entered. Information: ,in and The numbers of the busbars connected to the two ends of the tie switch are indicated respectively. and This is a binary constant; a value of 0 indicates the location is at the beginning of the busbar, and a value of 1 indicates the location is at the end of the busbar. Simultaneously, in order from beginning to end, the node number of the energy router or substation connected to each feeder on the busbar, as well as the distance of that feeder node from the beginning of the line, are entered. .

[0057] The established power flow equations include: power balance equations for each feed node of the bus; node power balance equations satisfied at the beginning and end of each bus; Ohm's law equations to be satisfied for each segment of the bus; Ohm's law equations to be satisfied for the bus tie switches; Ohm's law equations for the energy router feeders or substation feeders; constraints that power can only flow through closed tie lines; capacity constraints for each feeder / bus and voltage amplitude constraints for each node; and droop control characteristic equations for the grid-connected ports of the energy router.

[0058] Equation (18) represents the power balance equation for each feed node of the busbar; (18) Equations (19) and (20) represent the nodal power balance equations satisfied at the beginning and end of each busbar, respectively; (19) (20) in Indicates the power of the tie switch, with the reference direction being from Node pointing to node.

[0059] Equation (21) represents the Ohm's law equation that each segment on the busbar must satisfy. This represents the resistance per unit length of the busbar; (twenty one) Equation (22) represents the Ohm's law equation that the bus tie switch needs to satisfy, where The subscript will be When the value is 0 or 1, it is set to 1 or 1 respectively. This indicates that the value corresponds to the starting voltage or the ending voltage. Indicates the contact resistance of the interconnecting switch; (twenty two) Equation (23) represents Ohm's law equation for energy router feeders or substation feeders. This indicates the resistance of each feeder. This indicates the power flowing through this feeder; (twenty three) Equation (24) indicates that power can only flow through closed tie lines; (twenty four) Equations (25) to (28) represent the capacity constraints of each feeder / bus and the voltage amplitude constraints of each node.

[0060] (25) (26) (27) (28) Equation (29) represents the droop control characteristic equation of the grid-connected port of the energy router; (29) in, This represents the square of the DC bus voltage reference value. This indicates a reference value for the DC capacitor voltage of the energy router. express The voltage of the DC capacitor of the energy router at the node. express Reference value for the power of the grid-connected port of the energy router on the node. This represents the droop factor with respect to the grid connection point voltage. This represents the droop factor of the DC capacitor voltage of the power router itself.

[0061] S5. Based on the local energy management strategy of the self-consistent energy router, establish constraints on the tiered energy supply strategy and energy management strategy of the energy storage port of the energy router. The self-consistency characteristic of an energy router refers to its ability to achieve energy self-sufficiency and localized supply. Energy routers used to build microgrids contain various types of ports, including high-entropy energy ports, photovoltaic ports, grid-connected ports, energy storage ports, and load ports. To improve the economic efficiency of normal operation and the continuous power supply capability for emergency backup, various ports need to adopt reasonable energy release sequences and energy management measures. This solution optimizes the energy usage sequence of each port by monitoring the DC capacitor voltage of the energy router: before generating voltage and power control signals for each port, it first determines whether the DC capacitor voltage is within the operating range of the power source. When the DC voltage gradually decreases, various types of power sources are allowed to discharge in the order of high-entropy energy, photovoltaic ports, grid-connected ports, and energy storage ports. This allows for the determination of the energy utilization sequence of each port using local measurement data without relying on direct communication between the ports. Figure 3 As shown.

[0062] The energy storage port will consider the adaptive droop characteristic of maintaining the stability of the DC capacitor voltage based on its different states of charge. Its energy release characteristic is expressed as a piecewise function: (30) in, Indicates the output power of the battery. This indicates the reference value for battery power. This represents the power-voltage droop factor. and Indicates energy router exist The DC capacitor voltage at any given time and its state of charge (SOC) of the battery. and The low and high thresholds represent the state of charge. and Represents the minimum and maximum values ​​of the state of charge. and This refers to the adjustment factor for mitigating over-discharge and overshoot. This indicates the reference value of the DC capacitor voltage when the energy storage port plays a dominant regulatory role.

[0063] When the state of charge is below the low threshold, a strategy to reduce discharge is adopted to mitigate over-discharge; when the state of charge is between the low and high thresholds, a direct droop control strategy is adopted; when the state of charge is above the high threshold, an accelerated discharge strategy is adopted to mitigate overcharging.

[0064] Considering that the ports of the energy router will adopt different operating modes depending on the DC voltage range, auxiliary binary variables and the Big M method are introduced to linearize the operating state of the energy router, and the power balance equation of the energy router, the judgment constraint of each port reaching the maximum discharge power, and the discharge strategy and operation constraints of the energy storage port are established.

[0065] Equation (31) represents the power balance equation inside the energy router; (31) Equations (32) to (35) indicate that when the DC voltage is lower than the minimum adjustment threshold of the high-entropy energy source or photovoltaic port, the high-entropy energy source and photovoltaic port must have reached their maximum output power. (32) (33) (34) (35) Equations (36) to (37) indicate that when the DC voltage is higher than the minimum regulation threshold of the grid connection port, the energy storage will not participate in the discharge. (36) (37) Equations (38) to (46) represent the discharge strategy and operating constraints of the energy storage port.

[0066] (38) (39) (40) (41) (42) (43) (44) (45) (46) Among the above constraints and These represent the maximum power at the high entropy and photovoltaic ports, respectively. It represents the power consumption at the load port and can be considered a known constant when solving problems on a short time scale; These represent the output power of the photovoltaic port, high-entropy port, and energy storage port, respectively. to These represent the minimum threshold values ​​corresponding to the start of discharge at the high-entropy port, photovoltaic port, grid-connected port, and energy storage port, respectively, to maintain the DC bus voltage. Indicates the first The load of the energy router in the first A binary variable indicating whether it is charged at any given time. The variables represented are all auxiliary binary variables. , , These are binary variables representing whether the high-entropy, photovoltaic, and energy storage ports have reached their maximum discharge power, respectively. A value of 0 indicates that the maximum power has been reached, while a value of 1 indicates that the maximum power has not been reached and the system is within a range with a margin of error. , , These respectively indicate whether the remaining energy storage capacity is located in... , , Within the specified range, energy management strategies are adopted respectively: reducing discharge, direct drooping, and accelerating discharge.

[0067] S6. With the main goal of improving the power supply and protection capabilities of key functions of intelligent connected devices, an objective function for the dual bus reconfiguration optimization problem is established, and case verification analysis is conducted.

[0068] When determining the fault isolation and topology reconfiguration strategy for a road microgrid, the importance and power supply requirements of the intelligent connected devices should be taken into account. The main goal should be to improve the power supply and protection capabilities of the key functions of the intelligent connected devices. At the same time, the number of switching operations during the topology reconfiguration process should be minimized, and the redundancy of energized equipment during dual-bus operation should be reduced as much as possible.

[0069] The established objective function includes the following components: a weighted term based on the importance index of the load on each energy router, reflecting the priority given to power restoration of critical smart connected devices; a penalty term related to the number of switching actions to reduce the operational complexity during the reconfiguration process; a penalty term related to the simultaneous connection of dual ports of the energy router to the bus to reduce the resonance risk caused by the coupling of the microgrid and the energy router control characteristics; and a penalty term related to the tie switch that bridges the first and second sets of buses, meaning that the same set of buses should be given priority when achieving the same topology connectivity maintenance effect.

[0070] (47) in, For the first The importance index of the load on each energy router This is a penalty coefficient related to the number of switching actions; if the energy router is connected to two active networks through feeders at two grid-connected ports, it increases the risk of resonance caused by the coupling of the microgrid and energy router control characteristics. If both ports are simultaneously connected to the bus, the binary variable... Equals 1, This represents the relevant penalty coefficient; This indicates the penalty factor associated with the backup contact switch. This indicates a tie switch that connects the first and second busbars, such as... Figure 1 When using switches (#A-1, #B-2) and (#A-2, #B-1) to achieve the same topology connectivity, the same set of buses should be given priority.

[0071] In another embodiment of the present invention, a smart connected microgrid dual-bus topology reconfiguration and power supply maintenance system is provided. This system can be used to implement the above-mentioned smart connected microgrid dual-bus topology reconfiguration and power supply maintenance method. Specifically, the smart connected microgrid dual-bus topology reconfiguration and power supply maintenance system includes an operation module, a topology module, a radiation module, a power flow module, an energy module, and a solution module.

[0072] The operation module is used to construct a dual-bus microgrid structure including a first DC bus and a second DC bus. A four-position tie switch is set between the first DC bus and the second DC bus. Based on the state of the four-position tie switch and the state of the switch connected to the mains power, the operation mode of the dual-bus microgrid is determined. The topology module is used to establish the topology operation rules and live logic constraints of the dual-bus microgrid based on the structure and operation mode of the dual-bus microgrid. The constraints are based on mixed integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. The radial module is used to introduce the concepts of virtual power flow and virtual branches based on the topology operation rules and energized logic constraints, and to establish the radial and connectivity constraints of the dual-bus microgrid operation. The power flow module is used to establish DC microgrid power flow constraints based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, combined with the radial and connectivity constraints. An energy module is used to establish local energy management policy constraints for the energy router. The policy includes the tiered energy release sequence of each energy port of the energy router and the segmented energy management of the energy storage port based on the state of charge. The solution module is used to establish the objective function of the reconfiguration optimization model with the goal of maximizing the power supply capability of key functions of intelligent connected devices, and to solve the topology reconfiguration scheme based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints.

[0073] This invention provides a terminal device comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to achieve corresponding method flows or corresponding functions. The processor described in this embodiment can be used in the operation of a dual-bus topology reconfiguration and power supply maintenance method for intelligent connected microgrids, including: A dual-bus microgrid structure comprising a first DC bus and a second DC bus is constructed, with a four-position tie switch installed between the first and second DC buses. Based on the states of the four-position tie switches and the status of the mains-connected switches, the operation mode of the dual-bus microgrid is determined. Based on the dual-bus microgrid structure and operation mode, topology operation rules and live logic constraints are established for the dual-bus microgrid. These constraints are based on mixed-integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. Based on the topology operation rules and live logic constraints, the concepts of virtual power flow and virtual branches are introduced to establish the operation mode of the dual-bus microgrid. The system incorporates radial and connectivity constraints; based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, and combined with the radial and connectivity constraints, it establishes DC microgrid power flow constraints; it establishes local energy management strategy constraints for energy routers, including the tiered energy release sequence of each energy port of the energy router and segmented energy management of energy storage ports based on state of charge; with the goal of maximizing the power supply capability of key functions of intelligent connected devices, it establishes the objective function of the reconfiguration optimization model, and solves it based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints to obtain the topology reconfiguration scheme.

[0074] Please see Figure 5 The terminal device is a computer device. In this embodiment, the computer device 60 includes a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61. When executed by the processor 61, the computer program 63 implements the intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method of this embodiment. To avoid repetition, these details are not elaborated here. Alternatively, when executed by the processor 61, the computer program 63 implements the functions of each model / unit in the intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance system of this embodiment. To avoid repetition, these details are not elaborated here.

[0075] Computer device 60 can be a desktop computer, laptop, handheld computer, cloud server, or other computing device. Computer device 60 may include, but is not limited to, a processor 61 and a memory 62. Those skilled in the art will understand that... Figure 5 This is merely an example of computer device 60 and does not constitute a limitation on computer device 60. It may include more or fewer components than shown, or combine certain components, or different components. For example, computer device may also include input / output devices, network access devices, buses, etc.

[0076] The processor 61 may be a Central Processing Unit (CPU), or other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0077] The memory 62 can be an internal storage unit of the computer device 60, such as a hard disk or memory of the computer device 60. The memory 62 can also be an external storage device of the computer device 60, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on the computer device 60.

[0078] Furthermore, the memory 62 may include both internal storage units and external storage devices of the computer device 60. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 can also be used to temporarily store data that has been output or will be output.

[0079] Please see Figure 6 The terminal device is an electronic device 600, which is manifested in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one processing unit 610, at least one storage unit 620, a bus 630 connecting different platform components (including storage unit 620 and processing unit 610), a display unit 640, etc.

[0080] The storage unit stores program code, which can be executed by the processing unit 610 to perform the steps described in the method section of this specification according to various exemplary embodiments of the present invention. For example, the processing unit 610 can perform actions such as... Figure 7 The steps are shown in the figure.

[0081] Storage unit 620 may include a readable medium in the form of a volatile storage unit, such as random access memory (RAM) 6201 and / or cache memory 6202, and may further include a read-only memory (ROM) 6203.

[0082] Storage unit 620 may also include a program / utility 6204 having a set (at least one) program module 6205, such program module 6205 including but not limited to: operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0083] Bus 630 can represent one or more of several types of bus structures, including a memory cell bus or memory cell controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of the multiple bus structures.

[0084] Electronic device 600 can also communicate with one or more external devices 700 (e.g., keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 600, and / or with any device that enables electronic device 600 to communicate with one or more other computing devices (e.g., router, modem). This communication can be performed via input / output interface 650. Furthermore, electronic device 600 can also communicate with one or more networks (e.g., local area network, wide area network, and / or public network, such as the Internet) via network adapter 660. Network adapter 660 can communicate with other modules of electronic device 600 via bus 630. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 600, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms.

[0085] Example 4 This invention also provides a storage medium, specifically a computer-readable storage medium, which is a memory device in a terminal device for storing programs and data. It is understood that the computer-readable storage medium here can include both built-in storage media in the terminal device and extended storage media supported by the terminal device; it can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor, which can be one or more computer programs (including program code). More specific examples of the computer-readable storage medium include: an electrical connection with one or more wires, a portable disk, a hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical fiber, portable compact disk read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.

[0086] Computer-readable storage media also include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable storage medium can also be any readable medium other than a readable storage medium that can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium can be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, radio frequency, etc., or any suitable combination thereof.

[0087] Program code for performing the operations of this invention can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The program code can execute entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0088] One or more instructions stored in a computer-readable storage medium can be loaded and executed by a processor to implement the corresponding steps of the intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method in the above embodiments; one or more instructions in the computer-readable storage medium are loaded and executed by the processor in the following steps: A dual-bus microgrid structure comprising a first DC bus and a second DC bus is constructed, with a four-position tie switch installed between the first and second DC buses. Based on the states of the four-position tie switches and the status of the mains-connected switches, the operation mode of the dual-bus microgrid is determined. Based on the dual-bus microgrid structure and operation mode, topology operation rules and live logic constraints are established for the dual-bus microgrid. These constraints are based on mixed-integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. Based on the topology operation rules and live logic constraints, the concepts of virtual power flow and virtual branches are introduced to establish the operation mode of the dual-bus microgrid. The system incorporates radial and connectivity constraints; based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, and combined with the radial and connectivity constraints, it establishes DC microgrid power flow constraints; it establishes local energy management strategy constraints for energy routers, including the tiered energy release sequence of each energy port of the energy router and segmented energy management of energy storage ports based on state of charge; with the goal of maximizing the power supply capability of key functions of intelligent connected devices, it establishes the objective function of the reconfiguration optimization model, and solves it based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints to obtain the topology reconfiguration scheme.

[0089] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0090] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0091] The bus-tie switch topology of a dual-bus microgrid cluster in a smart connected city road demonstration area in Tianjin is analyzed, such as... Figure 4 The above mixed-integer programming model is used to characterize the network topology constraints and dual-bus operation rule constraints, which can initially obtain its topology reconfiguration operation mode to cope with common fault scenarios. The schematic diagram of the road energy system microgrid is shown below. The system contains two sets of DC buses, which are divided into three sections. There is a four-position tie switch between each section. 1 and 2 represent substation nodes, 3, 4, 5 and 4, 5, 6 represent the two sets of DC buses respectively, and 9-14 represent the various energy routers.

[0092] When the microgrid is operating normally, all energy routers are connected to the substation AC / DC#A via the first set of DC buses. At this time, the energized line topology in the system includes connected switches or feeders such as (1,3), (3,5), (5,7), (3,9), (3,10), (5,11), (5,12), (7,13), and (7,14). Considering different types of faults in the system, the system will disconnect the faulty switch or bus and disconnect the surrounding switches to achieve fault isolation. Afterward, the system will perform switching and reconfiguration according to safety constraints to achieve topology connectivity and high-elasticity power supply maintenance. The results of the reconfiguration are shown in Table 2.

[0093] Table 2. Examples of Fault Scenarios and Topology Reconstruction Results in a Smart Connected City Road Demonstration Zone in Tianjin

[0094] In summary, this invention provides a method and system for dual-bus topology reconfiguration and power supply maintenance in intelligent connected microgrids. First, it establishes a flexible dual-bus physical foundation. Then, based on this structure, it progressively establishes mathematical rules to ensure the safety and feasibility of the reconfiguration scheme, including topology logic, network morphology, electrical flow, and energy management constraints. Finally, these constraints are integrated into an optimization model with the primary goal of ensuring the power supply to critical equipment. Through the dual-bus structure and four-position tie switch design, it enables flexible switching between various operating modes, solving the problem of insufficient flexibility in single-bus topologies. Using mixed-integer optimization modeling and other methods, it accurately characterizes the fault isolation logic and operating specifications of the dual-bus system, adapting to the specific characteristics of road microgrids. Through tiered energy release and segmented energy storage management using energy routers, it improves energy utilization efficiency and emergency power supply sustainability. The optimization model, with the goal of ensuring the power supply to critical intelligent connected equipment, achieves rational allocation of emergency resources. In extreme multi-point fault scenarios, it can quickly complete fault isolation and topology reconfiguration, restore power to critical equipment, significantly improve the power supply elasticity and reliability of road microgrids, and ensure the safe and stable operation of intelligent connected transportation systems.

[0095] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments 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. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0096] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0097] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0098] In the embodiments provided by this invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are merely illustrative. For instance, the division of modules or 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 through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0099] 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.

[0100] 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.

[0101] If the integrated module / 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, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random-access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0102] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus, and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for dual-bus topology reconfiguration and power supply maintenance in intelligent connected microgrids, characterized in that, Includes the following steps: A dual-bus microgrid structure including a first DC bus and a second DC bus is constructed, and a four-position tie switch is set between the first DC bus and the second DC bus. The operation mode of the dual-bus microgrid is determined based on the state of the four-position tie switch and the switch state of the mains power supply. Based on the aforementioned dual-bus microgrid structure and operation mode, topology operation rules and live logic constraints of the dual-bus microgrid are established. The constraints are based on mixed integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. Based on the aforementioned topology operation rules and live logic constraints, the concepts of virtual power flow and virtual branch are introduced to establish the radial and connectivity constraints for the operation of the dual-bus microgrid. Based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, and combined with the radial and connectivity constraints, a DC microgrid power flow constraint is established. Establish local energy management policy constraints for the energy router, the policy including the tiered energy release sequence of each energy port of the energy router and the segmented energy management of the energy storage port based on the state of charge; With the goal of maximizing the power supply capability of key functions of intelligent connected devices, an objective function of the reconfiguration optimization model is established, and the solution is obtained based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints.

2. The intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method according to claim 1, characterized in that, The grid connection ports of the substation-side rectifiers and energy routers distributed along the road are all connected to the first DC bus and the second DC bus via feeders; the first DC bus and the second DC bus are both divided into multiple sections, and each section is connected to the other through the four-position tie switch; the operating modes include grid-connected dual bus operation, grid-connected dual bus mutual support, grid-connected single bus operation, off-grid dual bus operation, off-grid dual bus mutual support, and off-grid single bus operation.

3. The intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method according to claim 2, characterized in that, The four-position interconnection switch is used to control the connection status between #A-1 and #B-1, #A-2 and #B-2, #A-1 and #B-2, and #A-2 and #B-1. The switches connected to the mains power include switch #A, switch #B, switch #E1, and switch #E2. Each switch contains two sub-switches, S1 and S2. Different operating modes are achieved by coordinating the closed and open states of the sub-switches with the four-position interconnection switch.

4. The intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method according to claim 1, characterized in that, The topology operation rules and live logic constraints include live logic constraints, radial topology constraints, and dual-busbar safe operation rules; the distribution network main transformer and rectifier nodes, each bus section and energy router are defined as the node set in the power network, and the branches of the transformer-side rectifier connected to the bus, the tie switches in the bus and the feed-in branches of the energy router grid connection port are defined as the line set in the power network. The live logic constraints include: the bus or node in a fault must be de-energized; when the bus or power supply is in a fault isolation state, the surrounding tie switches or feeder lines must be disconnected; an unenergized node can be energized through at most one switchable line; a bus node can only be energized after at least one of its surrounding switches is energized; and a switch can only be closed when at least one end is energized. The dual-busbar safe operation rules include calculating and constraining the number of switching actions at each step, and determining whether the energy router is simultaneously connected to two energized buses.

5. The intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method according to claim 1, characterized in that, The radial and connectivity constraints are based on the single-commodity flow theory and include: The total number of energized nodes minus the number of energized lines equals the number of root nodes participating in providing virtual power flow; the virtual power flow balance equation for potential root nodes and other nodes; segmented buses themselves do not have power sources and cannot serve as root nodes; potential root nodes include energy router nodes and mains transformer nodes, and can only serve as root nodes when energized; a node can only provide virtual power flow when it serves as a root node; lines can only flow through virtual power flow when energized.

6. The method for dual-bus topology reconfiguration and power supply maintenance of intelligent connected microgrids according to claim 1, characterized in that, The power flow constraints of the DC microgrid include: Power balance equations for each feeder node on the busbar; power balance equations for the beginning and end of each busbar; Ohm's law equations for each segment of the busbar, including the resistance per unit length of the busbar; Ohm's law equations for the busbar tie switches, including the contact resistance of the tie switches; Ohm's law equations for the energy router feeders or substation feeders, including the resistance of each feeder and the power flowing through them; power can only flow through closed tie lines; capacity constraints for each feeder / busbar and voltage amplitude constraints for each node; droop control characteristic equations for the grid-connected ports of the energy router.

7. The intelligent connected microgrid dual-bus topology reconfiguration and power supply maintenance method according to claim 6, characterized in that, The ports of the energy router include high-entropy energy ports, photovoltaic ports, grid-connected ports, energy storage ports, and load ports; the local energy management strategy constraints also include the energy router power balance equation and the judgment constraints for each port to reach its maximum discharge power. The judgment constraints are determined based on the comparison results of DC voltage and adjustment threshold of each port.

8. The method for dual-bus topology reconfiguration and power supply maintenance of intelligent connected microgrids according to claim 1, characterized in that, The tiered energy release sequence is determined by monitoring the DC capacitor voltage of the energy router. As the DC voltage gradually decreases, the energy is discharged in the following order: high-entropy energy port, photovoltaic port, grid-connected port, and energy storage port. The segmented energy management of the energy storage port based on the state of charge is specifically as follows: When the state of charge is below the low threshold, discharge is reduced; when the state of charge is between the low and high thresholds, direct droop control is used; when the state of charge is above the high threshold, discharge is accelerated.

9. The method for dual-bus topology reconfiguration and power supply maintenance of intelligent connected microgrids according to claim 1, characterized in that, The objective function includes a weighted term for the importance index of the load on each energy router, a penalty term related to the number of switching operations, a penalty term related to the simultaneous connection of two ports of the energy router to the bus, and a penalty term related to the tie switch that connects the first DC bus and the second DC bus.

10. A smart connected microgrid dual-bus topology reconfiguration and power supply maintenance system, characterized in that, include: The operation module is used to construct a dual-bus microgrid structure including a first DC bus and a second DC bus. A four-position tie switch is set between the first DC bus and the second DC bus. Based on the state of the four-position tie switch and the switch state of the mains power supply, the operation mode of the dual-bus microgrid is determined. The topology module is used to establish the topology operation rules and live logic constraints of the dual-bus microgrid based on the structure and operation mode of the dual-bus microgrid. The constraints are based on mixed integer optimization modeling and are used to characterize the isolation logic and dual-bus parallel operation specifications after bus and tie switch failures. The radial module is used to introduce the concepts of virtual power flow and virtual branches based on the topology operation rules and charged logic constraints, and to establish the radial and connectivity constraints of the dual-bus microgrid operation. The power flow module is used to establish DC microgrid power flow constraints based on the segmented feed and cross-interconnection characteristics of the dual-bus microgrid, combined with the radial and connectivity constraints. An energy module is used to establish local energy management policy constraints for the energy router. The policy includes the tiered energy release sequence of each energy port of the energy router and the segmented energy management of the energy storage port based on the state of charge. The solution module is used to establish the objective function of the reconfiguration optimization model with the goal of maximizing the power supply capability of key functions of intelligent connected devices, and to solve the topology reconfiguration scheme based on the topology operation rules and charged logic constraints, the radial and connectivity constraints, the DC microgrid power flow constraints, and the local energy management strategy constraints.

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