A micro-grid group flexible interconnection coordination control method adaptive to multiple types of faults

Abstract

The application provides a micro-grid group flexible interconnection coordination control method suitable for multiple types of faults, comprising: (1) adopting a differential equation to describe the mathematical relationship between the internal power, frequency and other physical quantities of a single micro-grid, and constructing a dynamic response model of the single micro-grid; (2) comprehensively considering the communication connection relationship of the power transmission lines and flexible interconnection devices between different micro-grids, and constructing a dynamic response model of the multiple micro-grid groups; (3) comprehensively considering the faults of the power transmission lines or flexible interconnection devices between the micro-grids, the generator trip-out faults in the micro-grids, the load loss-of-mains faults in the micro-grids, and the communication line faults between the micro-grids, judging the fault types, and implementing the micro-grid group flexible interconnection coordination control according to the fault type judgment result. The application improves the algebraic connectivity and robustness of the network, makes the system more stable, and can effectively guarantee the stable and safe operation of the micro-grid group.

Description

Technical Field

[0001] This invention belongs to the field of microgrid group fault handling, and more specifically relates to a flexible interconnection and coordinated control method for microgrid groups that adapts to multiple types of faults. Background Technology

[0002] A microgrid is a power supply and distribution system composed of distributed power sources, energy conversion devices, and loads. It can operate in both grid-connected and off-grid modes. Microgrids are an effective way to connect distributed generator sets to the distribution network. They effectively address the intermittency and instability of distributed generation, improve the efficiency of renewable energy utilization, and also feature energy interconnection. However, the output power of a microgrid composed of distributed generation units is unstable and significantly affected by the external environment. To address these issues, experts have proposed the concept of a microgrid cluster. Its working principle involves flexibly interconnecting multiple adjacent microgrids to form a microgrid cluster. By equipping distributed power sources with appropriately sized energy storage systems, power coordination and complementarity between microgrids are achieved, maintaining the stability of the microgrid cluster and enhancing system reliability. When a microgrid failure leads to system instability, real-time energy and information transfer between microgrids coordinates the system, ensuring stable operation of each microgrid within the microgrid cluster and improving power supply reliability. Furthermore, microgrid clusters can also be connected to the external power grid, achieving energy complementarity and better leveraging the advantages of both centralized and distributed power supply. In microgrid systems, flexible interconnection technology can improve system flexibility and reliability, and reduce the impact of system failures on power supply. When a failure occurs, flexible interconnection technology can achieve automatic switching of power supply by adjusting the power load and utilizing energy storage systems.

[0003] Common microgrid flexible interconnection technologies include:

[0004] Intelligent load management technology: By monitoring changes in power load through intelligent sensors, controllers, and communication networks, it enables refined management of power load, thereby improving the reliability of power supply.

[0005] Energy storage system technology: Connecting energy storage devices directly to microgrids and providing backup energy for electrical loads through the batteries of the energy storage devices, thereby realizing the backup function of power supply.

[0006] Operation and management system technology: It uses technologies such as cloud computing, Internet of Things, and big data to collect, analyze, and process the operation data of the microgrid system. Through intelligent control algorithms, it realizes functions such as real-time monitoring, remote control, and fault diagnosis of the system, ensuring the long-term stable operation of the microgrid.

[0007] Multi-source collaborative control technology: Through multi-source collaborative control, different types of power sources can work together to improve the power supply capacity and reliability of microgrid systems.

[0008] However, some technical challenges exist in the application of flexible interconnection technology, such as the coordinated control of equipment and the security and stability of data. Therefore, when using flexible interconnection technology, it is necessary to comprehensively consider the actual situation and operational requirements of the system and appropriately select suitable technical means or combinations of solutions. In general, the emergence of microgrid flexible interconnection technology has greatly promoted the energy transition process and has significant advantages in improving energy utilization efficiency and reliability. Summary of the Invention

[0009] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention aims to provide a flexible interconnection and coordinated control method for microgrid groups that can adapt to multiple types of faults, and to address and solve the problems of equipment coordinated control and safety and stability when microgrid groups face multiple types of faults.

[0010] To achieve the above objectives, this invention discloses a flexible interconnection and coordinated control method for microgrid groups that adapts to multiple types of faults, comprising the following steps:

[0011] (1) Differential equations are used to describe the mathematical relationships between power, frequency and other physical quantities within a single microgrid, and a dynamic response model of a single microgrid is constructed.

[0012] (2) Taking into account the communication connection relationship between transmission lines and flexible interconnection devices between different microgrids, a dynamic response model for multiple microgrid groups is constructed;

[0013] (3) Taking into account the faults of transmission lines or flexible interconnection devices between microgrids, generator tripping faults within microgrids, load power loss faults within microgrids, and communication line faults between microgrids in the dynamic response model, determine the fault type, and implement flexible interconnection coordination control of microgrid groups based on the fault type determination results.

[0014] Furthermore, in step (1), differential equations are used to describe the mathematical relationships between power, frequency, and other physical quantities within a single microgrid, thereby constructing a dynamic response model for the single microgrid. Specifically:

[0015] The dynamic equation of the i-th microgrid in the microgrid group is as follows:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021] In the formula, Δf is the change in frequency, and ΔP ti It is the change in output power of the diesel generator, ΔP gi It is the change in the position of the speed control valve, ΔP ei It is the change in integral control, Δδ i It is the change in rotor angle, ΔP ui It is the change in the control of the diesel generator, ΔP di It is the change in load disturbance, k pi It is the power system gain, k ei It is the integral control gain, k bi It is the frequency bias factor, R i T is the speed regulation coefficient. pi It is the time constant of the power system, T ti It is the time constant of the turbine, T gi It is the time constant of the speed controller, ψ i It is the physical neighbor node of the i-th microgrid, θ i It is the network neighbor node of the i-th microgrid, μ il η is the physical interconnection gain between the i-th microgrid and the l-th microgrid. il It is the network interconnection gain between the i-th microgrid and the l-th microgrid;

[0022] The above equation is expressed as

[0023]

[0024]

[0025] x i =[Δf i ΔP ti ΔP gi ΔP ei Δδ i ] T (8)

[0026]

[0027] u i =[ΔP ui ΔP di ] T (10)

[0028]

[0029] x l=[Δf l ΔP tl ΔP gl ΔP el Δδ l ] T (12)

[0030] Furthermore, in step (2), considering the communication connections between transmission lines and flexible interconnection devices between different microgrids, a dynamic response model for multiple microgrid groups is constructed, specifically as follows:

[0031] The state space of the entire microgrid group, comprising N microgrids, is:

[0032]

[0033] In the formula,

[0034]

[0035] x=[row(Δf i row(ΔP) ti row(ΔP) gi row(ΔP) ei row(Δδ) i )] T (15)

[0036]

[0037] u=[row(ΔP ui row(ΔP) di )] T (17)

[0038] g(μ i ,L p ) = column[μ i L p,i,1 … μ i L p,i,j … μ i L p,i,N (18)

[0039] g(η i ,L c = column[η i L c,i,1 …η i L c,i,j …η i L c,i,N (19)

[0040] In the formula, Δf i It is the change in frequency, ΔPti It is the change in output power of the diesel generator, ΔP gi It is the change in the position of the speed control valve, ΔP ei It is the change in integral control, Δδ i It is the change in rotor angle, ΔP ui It is the change in the control of the diesel generator, ΔP di It is the change in load disturbance, k pi It is the power system gain, k ei It is the integral control gain, k bi It is the frequency bias factor, R i T is the speed regulation coefficient. pi It is the time constant of the power system, T ti It is the time constant of the turbine, T gi It is the time constant of the speed controller, μ i It is the physical interconnect gain, η i It is the network interconnection gain; diag(a i ) is based on variable a i A diagonal matrix with diagonal elements, row(a i ) with variable a i A row vector containing row elements, column(a i ) is based on variable a i L is a column vector of column elements. p,i,j It is the Laplace matrix L of the microgrid p The element in the i-th row and j-th column, L c,i,j The Laplace matrix L of the communication network c The element in the i-th row and j-th column.

[0041] Furthermore, the definition of the fault type in step (3) is as follows:

[0042] a. Transmission line or flexible interconnection device failure: Problems or damage to the physical connections such as cables, lines or conductors connecting the various sub-microgrids in the microgrid group can cause the microgrid system to malfunction. Physical connection line failures may have a significant impact on the stability, reliability and security of the microgrid and may lead to serious consequences.

[0043] b. Generator tripping fault: Damage to internal components of the generator, poor circuit connection, or harsh external environment can lead to a decline in generator performance or even failure to operate normally. Generator failure may result in insufficient power supply to the microgrid system, equipment damage or shutdown, affecting the normal operation of the entire microgrid group;

[0044] c. Load loss fault: In a microgrid, some loads may suddenly disappear due to equipment failure, intentional damage, misoperation, etc. Load loss faults will cause voltage and frequency fluctuations in the microgrid, overcurrent or overvoltage of operating equipment, thereby affecting its stable operation, and even causing the microgrid group to collapse.

[0045] d. Communication line failure: Communication lines between the various sub-microgrids in a microgrid group may experience interruptions, delays, or errors during information transmission. Communication failures may affect information exchange and coordinated control between the various sub-microgrids, leading to control abnormalities in the overall microgrid or some microgrids in the microgrid group. The causes of communication failures may include unreasonable network topology, damaged hardware, incompatible communication protocols, and mismatched communication frequencies.

[0046] Furthermore, the specific steps for determining the fault type in step (3) are as follows:

[0047] a. Transmission line or flexible interconnection device fault: By analyzing data collected from the real-time power grid monitoring system, information such as the phase, voltage, and current of the fault is obtained, and digital signal processing and pattern recognition technologies are combined to locate the line fault;

[0048] b. Generator tripping fault: Real-time monitoring and analysis of generator output power, current and voltage parameters in the microgrid group are performed in real time through the real-time monitoring software installed on the microgrid management system. If an abnormality occurs, a warning or fault information will be displayed.

[0049] c. Load power failure: By installing real-time monitoring software on the microgrid management system, the electrical parameters in the microgrid group are monitored and analyzed in real time, including system voltage, current and power indicators. When a certain indicator suddenly changes or exceeds the preset range, it is determined that there may be a load power failure.

[0050] d. Communication line faults: The real-time monitoring software installed on the microgrid management system can monitor and analyze the communication lines in the microgrid group in real time. When the communication line is abnormal or interrupted, the software will prompt a warning or fault information.

[0051] Furthermore, in step (3), based on the fault type judgment result, flexible interconnection and coordinated control of the microgrid group is implemented, specifically including:

[0052] For transmission line or flexible interconnection device faults between microgrids and generator tripping faults within microgrids, control objectives and constraints are formulated for these faults. The control objectives are solved, and the flexible interconnection coordination control of microgrid groups under the two fault scenarios is achieved by optimizing the allocation of adjustable resources and load adjustment within the microgrid.

[0053] For load power failure faults in microgrids, control objectives and constraints for load power failure faults are formulated, control objectives are solved, and flexible interconnection and coordinated control of microgrid groups under this fault condition is achieved by optimizing the allocation of adjustable resources in the microgrid.

[0054] To address communication line faults between microgrids, control objectives and constraints for communication line faults are formulated, and the control objectives are solved to achieve flexible interconnection and coordinated control of the microgrid group under such fault conditions.

[0055] Furthermore, for faults in transmission lines or flexible interconnection devices between microgrids and generator tripping faults within microgrids, control objectives and constraints are formulated, specifically:

[0056]

[0057] In the formula, P ui C represents the output of the i-th adjustable resource. i (P ui L represents the output cost of the i-th adjustable resource. j K represents the adjustment requirement of the j-th load unit. j This represents the power loss penalty coefficient, indicating the cost of power loss for the load.

[0058] There are a total of 5 constraints for the control method, the first of which is the power balance equation:

[0059]

[0060] The second constraint is the generator output power constraint:

[0061] P ui,min ≤P ui ≤P ui,max (twenty two)

[0062] The third constraint is the load requirement constraint:

[0063] P dj,min ≤P dj ≤P dj,max (twenty three)

[0064] The fourth constraint is the load adjustment amount constraint:

[0065] L j,min ≤L j ≤L j,max (twenty four)

[0066] The fifth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids:

[0067]

[0068] In the formula, P ui P represents the output of the i-th adjustable resource. ui,min and P ui,max Let C represent the minimum and maximum limits of the adjustable resource output of the i-th unit, respectively. i (P ui Let P represent the output cost of the i-th adjustable resource. dj P represents the demand of the j-th load unit. dj,min and P dj,max These represent the minimum and maximum demand for the load, respectively. S ij This indicates the capacity of transmission lines or flexible interconnection devices between microgrids. P ij and Q ij These represent transmitted power and reactive power, respectively. L j This represents the adjustment requirement of the j-th load unit. and These represent the minimum and maximum values ​​for the load adjustment, respectively. K j This represents the power loss penalty coefficient, indicating the cost of power loss for the load.

[0069] By solving the above control objectives, and considering the impact of transmission line or flexible interconnection device faults between microgrids and generator tripping faults within the microgrid, we can find the adjustable resource output allocation scheme that minimizes the total cost, thereby achieving coordinated control of flexible interconnection of microgrid groups.

[0070] Furthermore, for load power failure faults within the microgrid, control objectives and constraints for load power failure faults are formulated, specifically as follows:

[0071]

[0072] In the formula, P ui C represents the output of the i-th adjustable resource. i (P ui ) represents the output cost of the i-th adjustable resource;

[0073] There are four constraints in the control method, the first of which is the power balance equation:

[0074]

[0075] The second constraint is the generator output power constraint:

[0076] P ui,min ≤P ui ≤P ui,max (28)

[0077] The third constraint is the load requirement constraint:

[0078] Pdj,min ≤P dj ≤P dj,max (29)

[0079] The fourth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids:

[0080]

[0081] In the formula, P ui P represents the output of the i-th adjustable resource. ui,min and P ui,max Let C represent the minimum and maximum limits of the adjustable resource output of the i-th unit, respectively. i (P ui P represents the output cost of the i-th adjustable resource. dj P represents the demand of the j-th load unit. dj,min and P dj,max S represents the minimum and maximum demand for this load, respectively. ij This indicates the capacity of transmission lines or flexible interconnection devices between microgrids. P ij and Q ij These represent transmission power and reactive power, respectively.

[0082] By solving the above control objectives, we can consider the impact of load power failures on the microgrid and find the adjustable resource output allocation scheme that minimizes the total cost, thereby realizing flexible interconnection and coordinated control of the microgrid group.

[0083] Furthermore, for load power failure faults within the microgrid, control objectives and constraints for load power failure faults are formulated, specifically as follows:

[0084] The first control objective is:

[0085] f1=maxλ2(L c (31)

[0086] The second goal is:

[0087] f2=min(max(eig(A))) (32)

[0088] Where eig(A) are the eigenvalues ​​of matrix A;

[0089] The second objective is also expressed as

[0090] f′2=max(min(|eig(A)|)) (33);

[0091] The constraints of the control method specifically include:

[0092] Laplace matrix constraints for communication networks:

[0093] λ2(L c )>0 (34)

[0094] eig(A)<0 (35)

[0095] sum(|TopLeft(L c )|)=Num c (36)

[0096] Among them, TopLeft(L c ) is the element in the upper right corner of the Laplace matrix of the communication network, Num c It refers to the number of communication links;

[0097] When solving for the control objective of communication line faults, the control method integrates two optimization objectives together, namely...

[0098]

[0099] Among them, f int It is a comprehensive optimization objective function. and These are two positive numbers controlling the proportion of two optimization objectives. The objectives are added together to construct the optimization model; a penalty function is used to handle the constraints.

[0100]

[0101] Among them, f fin The final optimization objective is ρ1, ρ2, and ρ3, which are positive numbers representing the degree of penalty functions for the control constraints. h(y) is a function where h(y) = 0 when y > 0 and h(y) = 1 when y ≤ 0. g(y) is a function where g(y) = 0 when y = 0 and g(y) = 1 when y ≠ 0.

[0102] The present invention has the following beneficial effects:

[0103] 1. The method of this invention is the first to address multiple types of fault problems, including transmission line or flexible interconnection device faults, generator tripping faults, load power loss faults, and communication line faults, and realizes flexible interconnection and coordinated control of microgrid groups.

[0104] 2. The method of this invention adopts dynamic response modeling technology to describe the mathematical relationship between physical quantities such as power and frequency in a single microgrid. For the first time, it comprehensively considers the physical and communication connections between multiple microgrids and constructs a dynamic response model for a microgrid group. Compared with traditional methods, it has more refined and detailed features.

[0105] 3. The method of the present invention utilizes the optimized allocation of output and load adjustment of adjustable resources within the microgrid to achieve flexible interconnection and coordinated control of the microgrid group under different fault conditions. At the same time, when formulating control objectives and constraints, the characteristics and limitations of different fault types are fully considered. Attached image description:

[0106] Figure 1 This is a schematic diagram of the communication connection of the physical connection of the microgrid group according to an embodiment of the present invention;

[0107] Figure 2 This is a diagram of the microgrid group connection lines and a schematic diagram of the Laplace matrix according to an embodiment of the present invention;

[0108] Figure 3 This is a schematic diagram of a Laplace matrix containing specific numerical values ​​according to an embodiment of the present invention;

[0109] Figure 4 This is a schematic diagram of flexible interconnection of microgrid groups according to an embodiment of the present invention;

[0110] Figure 5 This is a schematic diagram of the frequency and rotor angle deviation when the transmission line or flexible interconnection device fails during a comparison method in an embodiment of the present invention.

[0111] Figure 6 This is a schematic diagram of the frequency and rotor angle deviation when the transmission line or flexible interconnection device fails using the method of the present invention in an embodiment of the present invention;

[0112] Figure 7 This is a schematic diagram of the frequency and rotor angle deviation during generator tripping faults when using the comparison method in an embodiment of the present invention;

[0113] Figure 8 This is a schematic diagram of the frequency and rotor angle deviation when the generator trips during a fault, as described in an embodiment of the present invention.

[0114] Figure 9 This is a schematic diagram of the frequency and rotor angle deviation during a load power failure when using the comparison method in an embodiment of the present invention;

[0115] Figure 10 This is a schematic diagram of the frequency and rotor angle deviation during a load power failure when the method of the present invention is used in an embodiment of the present invention;

[0116] Figure 11 This is a schematic diagram of the frequency and rotor angle deviation when the communication line is faulty, using the comparison method in an embodiment of the present invention;

[0117] Figure 12 This is a schematic diagram of the frequency and rotor angle deviation when the communication line is faulted in an embodiment of the present invention using the method of the present invention;

[0118] Figure 13 This is a flowchart of a flexible interconnection and coordinated control method for microgrid groups that adapts to multiple types of faults, according to an embodiment of the present invention. Detailed Implementation

[0119] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments.

[0120] Please see Figure 13 This invention provides a flexible interconnection and coordinated control method for microgrid groups that adapts to multiple types of faults, comprising the following steps:

[0121] 1) Differential equations are used to describe the mathematical relationships between power, frequency and other physical quantities within a single microgrid, and a dynamic response model of the single microgrid is constructed.

[0122] 2) Taking into account the communication connections between transmission lines and flexible interconnection devices between different microgrids, a dynamic response model for multiple microgrid groups is constructed;

[0123] 3) Taking into account the faults of transmission lines or flexible interconnection devices between microgrids, generator tripping faults within microgrids, load power loss faults within microgrids, and communication line faults between microgrids in the dynamic response model, determine the fault type, and implement coordinated control of flexible interconnection of microgrid groups based on the fault type determination results.

[0124] Specifically, in step 1), differential equations are used to describe the mathematical relationships between power, frequency, and other physical quantities within a single microgrid, constructing a dynamic response model for the single microgrid.

[0125] The dynamic equation of the i-th microgrid in the microgrid group is as follows:

[0126]

[0127]

[0128]

[0129]

[0130]

[0131] In the formula, Δf is the change in frequency. ΔP ti This is the change in the output power of the diesel generator. ΔP gi This is the change in the position of the speed control valve. ΔP ei It is the change in integral control. Δδ i It is the change in rotor angle ΔP. ui This is the variable controlled by the diesel generator, ΔP.di It is the change in load disturbance. k pi It is the power system gain. k ei It is the integral control gain. k bi It is the frequency bias factor. R i T is the speed regulation coefficient. pi T is the time constant of the power system. ti T is the time constant of the turbine. gi It is the time constant of the speed governor. ψ i θ represents the physical neighbor nodes of the i-th microgrid (the set of microgrids connected to the i-th microgrid via transmission lines). i μ is the network neighbor node of the i-th microgrid (the set of microgrids that are connected to the i-th microgrid via communication lines). il η is the physical interconnection gain between the i-th microgrid and the l-th microgrid. il It is the network interconnection gain between the i-th microgrid and the l-th microgrid.

[0132] The above equation can be expressed as

[0133]

[0134]

[0135] x i =[Δf i ΔP ti ΔP gi ΔP ei Δδ i ] T (8)

[0136]

[0137] u i =[ΔP ui ΔP di ] T (10)

[0138]

[0139] x l =[Δf l ΔP tl ΔP gl ΔP el Δδ l ] T (12)

[0140] Specifically, in step 2), considering the communication connections between different microgrids (including transmission lines and flexible interconnection devices), a dynamic response model for multiple microgrid groups is constructed, specifically as follows:

[0141] Specifically, in this embodiment, the communication connection relationships of the physical connections (including transmission lines and flexible interconnection devices) between different microgrids are as follows: Figure 1 As shown in the figure, this is a typical schematic diagram of the physical and communication connections of a microgrid group.

[0142] The state space of the entire microgrid group, comprising N microgrids, is:

[0143]

[0144] In the formula,

[0145]

[0146]

[0147] x=[row(Δf i row(ΔP) ti row(ΔP) gi row(ΔP) ei row(Δδ) i )] T (15)

[0148]

[0149] u=[row(ΔP ui row(ΔP) di )] T (17)

[0150] g(μ i ,L p ) = column[μ i L p,i,1 … μ i L p,i,j … μ i L p,i,N (18)

[0151] g(η i ,L c = column[η i L c,i,1 …η i L c,i,j …η i L c,i,N (19)

[0152] In the formula, Δf i It is the change in frequency, ΔP ti It is the change in output power of the diesel generator, ΔP gi It is the change in the position of the speed control valve, ΔP ei It is the change in integral control, Δδ i It is the change in rotor angle, ΔP ui It is the change in the control of the diesel generator, ΔP di It is the change in load disturbance, k pi It is the power system gain, k ei It is the integral control gain, k bi It is the frequency bias factor, R i T is the speed regulation coefficient. pi It is the time constant of the power system, T ti It is the time constant of the turbine, T gi It is the time constant of the speed controller, μ i It is the physical interconnect gain, η i It is the network interconnection gain; diag(a i ) is based on variable a i A diagonal matrix with diagonal elements, row(a i ) with variable a i A row vector containing row elements, column(a i ) is based on variable a i L is a column vector of column elements. p,i,j It is the Laplace matrix L of the microgrid p The element in the i-th row and j-th column, L c,i,j The Laplace matrix L of the communication network c The element in the i-th row and j-th column.

[0153] Specifically, in step 3), considering faults in transmission lines or flexible interconnection devices between microgrids, generator tripping faults within microgrids, load power loss faults within microgrids, and communication line faults between microgrids, the specific fault type is determined. Based on the fault type determination result, the following steps of flexible interconnection coordination control for the microgrid group are implemented:

[0154] A microgrid cluster is a complex system formed by the interconnection of multiple microgrids. A microgrid is a power network composed of multiple interconnected power systems; it is a small-scale, distributed power system that enables the mutual transmission and sharing of electrical energy. Because a microgrid cluster consists of multiple interconnected microgrids, failure to address faults in a timely manner will affect the normal operation of the entire system. This patent primarily considers the following types of faults:

[0155] a. Transmission line or flexible interconnection device failure: Problems or damage to the physical connections such as cables, lines, or conductors connecting the various sub-microgrids in a microgrid cluster can cause the microgrid system to malfunction. Physical connection line failures can have a significant impact on the stability, reliability, and security of the microgrid and may lead to serious consequences.

[0156] b. Generator Tripping Fault: The most important power generation equipment in a microgrid is the generator. Damage to internal components, poor circuit connections, or harsh external environments can cause generator performance to degrade or even prevent normal operation. Generator failures may lead to insufficient power supply to the microgrid system, equipment damage, or shutdowns, affecting the normal operation of the entire microgrid group.

[0157] c. Load loss faults: In microgrids, some loads may suddenly disappear due to equipment failure, intentional sabotage, or misoperation. Load loss faults can cause voltage and frequency fluctuations in the microgrid, overcurrent or overvoltage in operating equipment, thereby affecting its stable operation and even causing the microgrid cluster to collapse.

[0158] d. Communication line failure: Communication lines between the various sub-microgrids in a microgrid cluster may experience interruptions, delays, or errors during information transmission. Communication failures can affect information exchange and coordinated control between the sub-microgrids, leading to control anomalies in the overall microgrid or parts of the microgrid cluster. Causes of communication failures may include an unreasonable network topology, damaged hardware, incompatible communication protocols, and mismatched communication frequencies.

[0159] Taking into account faults in transmission lines or flexible interconnection devices between microgrids, generator tripping faults within a microgrid, load power loss faults within a microgrid, and communication line faults between microgrids, the specific fault type is determined using the following method:

[0160] a. Transmission line or flexible interconnection device faults: By analyzing data collected through the real-time power grid monitoring system, information such as the phase, voltage, and current of the fault is obtained, and digital signal processing and pattern recognition technologies are used to locate the line fault.

[0161] b. Generator tripping fault: Real-time monitoring software installed on the microgrid management system monitors and analyzes parameters such as generator output power, current, and voltage in the microgrid group in real time. If an abnormality occurs, it will provide a warning or fault information.

[0162] c. Load power failure: By installing real-time monitoring software on the microgrid management system, the electrical parameters within the microgrid group are monitored and analyzed in real time, including indicators such as system voltage, current, and power. When a certain indicator suddenly changes or exceeds the preset range, it is determined that there may be a load power failure.

[0163] d. Communication line faults: The real-time monitoring software installed on the microgrid management system can monitor and analyze the communication lines in the microgrid group in real time. When the communication line is abnormal or interrupted, the software will prompt a warning or fault information.

[0164] Specifically, control objectives are set for two types of faults: transmission line or flexible interconnection device faults between microgrids, and generator tripping faults within a microgrid. These objectives are as follows:

[0165]

[0166] In the formula, P ui C represents the output of the i-th adjustable resource. i (P ui L represents the output cost of the i-th adjustable resource. j K represents the adjustment requirement of the j-th load unit. j This represents the power loss penalty coefficient, which indicates the cost of power loss for the load.

[0167] Specifically, constraints are established for transmission line or flexible interconnection device faults between microgrids, and generator tripping faults within a microgrid. By optimizing the allocation of adjustable resources within the microgrid and adjusting the load, coordinated control of the flexible interconnection of the microgrid group under these two fault scenarios is achieved.

[0168] To address faults in transmission lines or flexible interconnection devices between microgrids, as well as generator tripping faults within a microgrid, coordinated control of the flexible interconnection of microgrid groups is achieved by optimizing the allocation of adjustable resources and load adjustments within the microgrid. There are five constraints, the first of which is the power balance equation:

[0169]

[0170] The second constraint is the generator output power constraint:

[0171] P ui,min ≤P ui ≤P ui,max (twenty two)

[0172] The third constraint is the load requirement constraint:

[0173] P dj,min ≤P dj ≤P dj,max (twenty three)

[0174] The fourth constraint is the load adjustment amount constraint:

[0175] L j,min ≤L j ≤L j,max (twenty four)

[0176] The fifth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids:

[0177]

[0178] In the formula, P ui P represents the output of the i-th adjustable resource. ui,min and P ui,max Let C represent the minimum and maximum limits of the adjustable resource output of the i-th unit, respectively. i (P ui Let P represent the output cost of the i-th adjustable resource. dj P represents the demand of the j-th load unit. dj,min and P dj,max These represent the minimum and maximum demand for the load, respectively. S ij This indicates the capacity of transmission lines or flexible interconnection devices between microgrids. P ij and Q ij These represent transmitted power and reactive power, respectively. L j This represents the adjustment requirement of the j-th load unit. and These represent the minimum and maximum values ​​for the load adjustment, respectively. K j This represents the power loss penalty coefficient, which indicates the cost of power loss for the load.

[0179] By solving the above optimization model, we can simultaneously consider the impact of transmission line or flexible interconnection device faults between microgrids and generator tripping faults within the microgrid on the microgrid, and find the adjustable resource output allocation scheme that minimizes the total cost, thereby realizing the coordinated control of flexible interconnection of microgrid groups.

[0180] Specifically, for load power loss faults within the microgrid, control objectives for this type of fault are formulated as follows:

[0181]

[0182] In the formula, P ui C represents the output of the i-th adjustable resource. i (P ui ) represents the output cost of the i-th adjustable resource.

[0183] Specifically, for load power loss faults within a microgrid, constraints for such faults are established. By optimizing the allocation of adjustable resources within the microgrid, flexible interconnection and coordinated control of the microgrid group under this fault condition is achieved. Specifically:

[0184] To address load power outages within a microgrid, flexible interconnection and coordinated control of the microgrid group are achieved by optimizing the allocation of adjustable resources within the microgrid. There are four constraints, the first being the power balance equation:

[0185]

[0186] The second constraint is the generator output power constraint:

[0187] P ui,min ≤P ui ≤P ui,max (28)

[0188] The third constraint is the load requirement constraint:

[0189] P dj,min ≤P dj ≤P dj,max (29)

[0190] The fourth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids:

[0191]

[0192] In the formula, P ui P represents the output of the i-th adjustable resource. ui,min and P ui,max Let C represent the minimum and maximum limits of the adjustable resource output of the i-th unit, respectively. i (P ui Let P represent the output cost of the i-th adjustable resource. dj P represents the demand of the j-th load unit. dj,min and P dj,max These represent the minimum and maximum demand for the load, respectively. S ij This indicates the capacity of transmission lines or flexible interconnection devices between microgrids. P ij and Q ij These represent transmission power and reactive power, respectively.

[0193] By solving the above optimization model, we can consider the impact of load power failures on the microgrid and find the adjustable resource output allocation scheme that minimizes the total cost, thereby realizing flexible interconnection and coordinated control of the microgrid group.

[0194] Specifically, for communication line faults between microgrids, an optimization objective is formulated for a coordinated control method for flexible interconnection of microgrid groups that takes into account communication line faults between microgrids. The specific objective is as follows:

[0195] The communication network between microgrids should be a connected graph. Therefore, we need to ensure that the second smallest eigenvalue of the Laplace matrix of the communication network is greater than 0, i.e., λ²(L... c) > 0. Furthermore, considering λ2(L c λ²(L) is a metric for measuring the convergence speed or performance of consensus algorithms. Networks with relatively high algebraic connectivity are necessarily robust to faults, and it is hoped that λ²(L) will be the most effective convergence. c The size is large enough. Therefore, the first objective of the flexible interconnection coordinated control model for microgrid groups considering multiple fault types is...

[0196] f1=maxλ2(L c (31)

[0197] Secondly, the eigenvalues ​​of matrix A reflect the dynamic behavior of the entire system. If there are eigenvalues ​​with real parts greater than 0, the system is unstable. Therefore, we need to ensure that the real parts of all eigenvalues ​​are less than 0. Furthermore, considering that the greater the distance between the eigenvalues ​​and the imaginary axis, the faster the system converges, we want the largest eigenvalue to be as small as possible. Therefore, the second objective of the flexible interconnection coordinated control model for microgrid groups considering multiple fault types is...

[0198] f2=min(max(eig(A))) (32)

[0199] Where eig(A) are the eigenvalues ​​of matrix A.

[0200] The second objective can also be expressed as

[0201] f′2=max(min(|eig(A)|)) (33)

[0202] Specifically, in step 9), constraints are established for the microgrid group flexible interconnection coordination control method considering communication line faults between microgrids, specifically:

[0203] The Laplace matrix constraint condition for the communication network is:

[0204] λ2(L c )>0 (34)

[0205] eig(A)<0 (35)

[0206] sum(|TopLeft(L c )|)=Num c (36)

[0207] Among them, TopLeft(L c ) is the element in the upper right corner of the Laplace matrix of the communication network, Num c It refers to the number of communication links.

[0208] The variable to be optimized is the Laplace matrix of the communication network, which is an N×N matrix. The off-diagonal elements are 0 or -1, and the diagonal elements are the negatives of the sum of the off-diagonal elements in the corresponding row. Furthermore, L... c It is a symmetric matrix. Therefore, we only need to optimize L. c The top right corner, L c The rest can be filled in automatically.

[0209] Specifically, in this embodiment, Figure 2 The diagram shows the communication and physical connections of a typical microgrid cluster, and the elements in the upper right corner of the Laplace matrix of the communication network are given. Figure 3 Give Figure 2 The actual value of the Laplace matrix of the microgrid connection line shown.

[0210] Specifically, the optimization objective and constraints of a flexible interconnection coordination control method for microgrid groups considering communication line faults between microgrids are solved to achieve flexible interconnection coordination control of microgrid groups under this fault condition.

[0211] The optimization model has two objectives that cannot be solved directly using traditional optimization algorithms. Therefore, the two optimization objectives are integrated into one, i.e.

[0212]

[0213] Among them, f int It is a comprehensive optimization objective function. and These are two positive numbers that control the ratio of two optimization objectives. In this invention patent, we construct an optimization model by adding the objectives together (e.g., f). int =af1+bf2), and some of the objectives are highlighted by selecting larger coefficients (a or b). The choice of coefficients may have a potential impact on the method.

[0214] Traditional optimization algorithms are typically used to solve unconstrained optimization problems. However, this model contains three constraints. This invention uses a penalty function to handle these constraints, i.e.

[0215]

[0216] Among them, f fin The final optimization objective is defined by ρ1, ρ2, and ρ3, which are positive numbers representing the degree of penalty functions controlling the constraints. h(y) is a function where h(y) = 0 when y > 0 and h(y) = 1 when y ≤ 0. g(y) is a function where g(y) = 0 when y = 0 and g(y) = 1 when y ≠ 0.

[0217] Specifically, in this embodiment, a flexible interconnection system of a microgrid group formed by the interconnection of ten microgrids is adopted, such as... Figure 4 As shown.

[0218] The parameters of microgrid 1, microgrid 3 and microgrid 5 are shown in Table 1:

[0219] Table 1 shows the microgrid parameters in the example.

[0220]

[0221] The parameters of microgrid 2, microgrid 4 and microgrid 6 are shown in Table 2:

[0222] Table 2 shows the microgrid parameters in the example.

[0223]

[0224] The parameters of microgrid 7-10 are shown in Table 3:

[0225] Table 3 shows the microgrid parameters in the example.

[0226]

[0227]

[0228] To verify the superiority of the method of the present invention under different fault conditions, a comparative method was established. This comparative method did not optimize the communication network, and the microgrid group used a randomly generated communication network for communication. The coordinated control performance of the microgrid group under transmission line or flexible interconnection device faults, generator tripping faults, load power loss faults, and communication line faults was tested using the method of the present invention and the comparative method, respectively.

[0229] For transmission line or flexible interconnection device faults, set Figure 4 A malfunction occurred in the flexible interconnection device between microgrid 1 and microgrid 2 in the system, causing the transmission line between microgrid 1 and microgrid 2 to be disconnected. Figure 5 This diagram illustrates the frequency and rotor angle deviation during a transmission line or flexible interconnection device fault, using a comparative method in an embodiment of the present invention. Figure 6This diagram illustrates the frequency and rotor angle deviations during transmission line or flexible interconnection device faults when using the method of this invention. The comparison shows that the frequency and rotor angle deviations during transmission line or flexible interconnection device faults using the method of this invention are smaller than those using the comparative method. Furthermore, it can be seen that the frequency and rotor angle reach a minimum value around 10 seconds using the comparative method, and this minimum value lasts for a relatively long time. In contrast, the frequency and rotor angle deviations using the method of this invention are effectively controlled within a short time, rapidly decreasing to near-steady-state values. This indicates that the method of this invention has a faster convergence speed and smaller convergence deviation when handling transmission line or flexible interconnection device faults. Therefore, the method of this invention has better control performance and stability when handling transmission line or flexible interconnection device faults, and can effectively ensure the stable and safe operation of microgrid groups.

[0230] For generator tripping faults, set Figure 4 A generator in microgrid 1 in the system tripped, causing the generator in microgrid 1 to go out of operation. Figure 7 The diagram shows the frequency and rotor angle deviation during a generator tripping fault when using the comparison method in an embodiment of the present invention. Figure 8 This diagram illustrates the frequency and rotor angle deviation during a generator tripping fault when using the method of this invention. The comparison shows that the frequency and rotor angle deviation during a generator tripping fault using the method of this invention are smaller than those using the comparative method. It can be seen that after a generator tripping fault occurs, the frequency and rotor angle deviations using the comparative method reach a maximum and minimum value in approximately 8 seconds, and this duration is relatively long, indicating poor system stability. However, the frequency and rotor angle deviations using the method of this invention can be effectively controlled within a short time, rapidly decreasing to near steady-state values. This demonstrates that the method of this invention has a faster convergence speed and smaller convergence deviation when handling generator tripping faults, enabling faster recovery of the system from the fault state to normal operation. Therefore, the method of this invention has better control performance and stability in handling generator tripping faults, effectively ensuring the stable and safe operation of microgrid groups.

[0231] For load power failure faults, set Figure 4 A power outage fault occurred in the loads of microgrid 1 in the system, causing the loads in microgrid 1 to go out of operation. Figure 9 This diagram illustrates the frequency and rotor angle deviation during a load power failure when using a comparative method in an embodiment of the present invention. Figure 10This diagram illustrates the frequency and rotor angle deviation during a load power failure when using the method of this invention. The comparison shows that the frequency and rotor angle deviation during a load power failure using the method of this invention are smaller than those using the comparative method. It can be seen that after a load power failure occurs, the frequency and rotor angle deviation reach a minimum value of approximately 0.5 seconds using the comparative method, and this minimum value lasts for a relatively long time, indicating poor system stability. However, the frequency and rotor angle deviations using the method of this invention are effectively controlled within a short time, rapidly decreasing to near steady-state values. This demonstrates that the method of this invention has a faster convergence speed and smaller convergence deviation when handling load power failures, enabling faster recovery of the system from the fault state to normal operation. Therefore, the method of this invention has better control performance and stability in handling load power failures, effectively ensuring the stable and safe operation of the microgrid.

[0232] For communication line faults, set Figure 4 A fault occurred in the communication line between microgrid 1 and microgrid 2 in the system, causing the communication line between microgrid 1 and microgrid 2 to be disconnected. Figure 11 This diagram illustrates the frequency and rotor angle deviations during a communication line fault when using a comparison method in an embodiment of the present invention. Figure 12 This diagram illustrates the frequency and rotor angle deviations during communication line faults when using the method of this invention in an embodiment of the invention. The comparison shows that the frequency and rotor angle of the method of this invention reach a stable state after a short transition. When considering faults in transmission lines or flexible interconnection devices, generator tripping faults, load power loss faults, and communication line faults, this method exhibits faster convergence speed and smaller convergence deviation. This is because the optimization method based on the quantum binary particle swarm optimization algorithm improves the second smallest eigenvalue λ2(L) of matrix A. c This reduces the largest eigenvalue of matrix A. The second smallest eigenvalue is λ2(L). c The convergence speed and performance of consensus algorithms are measured by their eigenvalues. Networks with relatively high algebraic connectivity are inherently robust to faults. A system is stable when the real parts of all eigenvalues ​​are less than 0; if any eigenvalue has a real part greater than 0, the system is unstable. Therefore, considering that the greater the distance between the eigenvalue and the imaginary axis, the faster the system converges, the smaller the largest eigenvalue, the better the system performance and convergence speed. Thus, using communication structure optimization and frequency modulation methods to solve the flexible interconnection coordination control model of microgrid groups considering multiple fault types exhibits good convergence speed and can significantly improve system performance.

[0233] Furthermore, a comparison shows that the communication structure optimization process and the frequency modulation method complete the transition process in a shorter time. Although the method exhibits some oscillations during frequency adjustment, the amplitude of these oscillations is no greater than that of the process without the proposed method, and the oscillations are brief. Therefore, the proposed control method can improve the frequency control performance of the optimized communication structure.

[0234] This invention presents a flexible interconnection coordination control method for microgrid clusters, aiming to improve the system's control performance and stability under fault conditions. The method exhibits superior coordination control performance under faults in transmission lines or flexible interconnection devices, generator tripping, load power loss, and communication lines. Specifically, the method demonstrates faster convergence speed and smaller convergence deviation when handling various faults, enabling faster recovery of the system from a fault state to normal operation. Furthermore, the method improves the second smallest eigenvalue of the system control matrix through an optimization method based on quantum binary particle swarm optimization, thereby reducing the largest eigenvalue and improving the network's algebraic connectivity and robustness, resulting in greater system stability. These findings demonstrate that the method exhibits excellent control performance and stability in handling the flexible interconnection coordination control problem of microgrid clusters, effectively ensuring the stable and safe operation of microgrid clusters.

[0235] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flexible interconnection and coordinated control method for microgrid groups adaptable to multiple types of faults, characterized in that, Includes the following steps: (1) Differential equations are used to describe the mathematical relationships between power, frequency and other physical quantities within a single microgrid, and a dynamic response model of a single microgrid is constructed. (2) Taking into account the communication connection relationship between transmission lines and flexible interconnection devices between different microgrids, a dynamic response model for multiple microgrid groups is constructed; (3) Taking into account the faults of transmission lines or flexible interconnection devices between microgrids, generator tripping faults within microgrids, load power loss faults within microgrids, and communication line faults between microgrids in the dynamic response model, determine the fault type, and implement flexible interconnection coordination control of microgrid groups based on the fault type determination results. In step (1), differential equations are used to describe the mathematical relationships between power, frequency, and other physical quantities within a single microgrid, and a dynamic response model of the single microgrid is constructed, specifically as follows: The dynamic equation of the i-th microgrid in the microgrid group is as follows: （1）； （2）； （3）； （4）； （5）； In the formula, It is the change in frequency. It is the change in the output power of the diesel generator. It is the change in the position of the speed control valve. It is the change in integral control. It is the change in rotor angle. It is a variable controlled by the diesel generator. It is the change in load disturbance. It is the power system gain. It is integral control gain. It is the frequency bias factor. This is the speed regulation coefficient. It is the time constant of the power system. It is the time constant of the turbine. It is the time constant of the speed controller. It is the physical neighbor node of the i-th microgrid. It is the network neighbor node of the i-th microgrid. It is the physical interconnection gain between the i-th microgrid and the l-th microgrid. It is the network interconnection gain between the i-th microgrid and the l-th microgrid; The above equation is expressed as （6）； （7）； （8）； （9）； （10）； （11）； （12）； In step (2), considering the communication connection relationships between transmission lines and flexible interconnection devices between different microgrids, a dynamic response model for multiple microgrid groups is constructed, specifically as follows: The state space of the entire microgrid group, comprising N microgrids, is: （13）； In the formula, （14）； （15）； （16）； （17）； （18）； （19）； In the formula, It is the change in frequency. It is the change in the output power of the diesel generator. It is the change in the position of the speed control valve. It is the change in integral control. It is the change in rotor angle. It is a variable controlled by the diesel generator. It is the change in load disturbance. It is the power system gain. It is integral control gain. It is the frequency bias factor. This is the speed regulation coefficient. It is the time constant of the power system. It is the time constant of the turbine. It is the time constant of the speed controller. It is the physical interconnect gain. It is the network interconnection gain; diag(a i ) is based on variable a i A diagonal matrix with diagonal elements, row(a i ) with variable a i Let column(a) be a row vector of row elements. i ) is based on variable a i A column vector of column elements. It is a microgrid Laplace matrix The element in the i-th row and j-th column, It is the Laplace matrix of the communication network. The element in the i-th row and j-th column.

2. The microgrid group flexible interconnection coordinated control method adaptable to multiple types of faults according to claim 1, characterized in that, The definition of the fault type in step (3) is as follows: a. Transmission line or flexible interconnection device failure: Problems or damage to the physical connections such as cables, lines or conductors connecting the various sub-microgrids in the microgrid group can cause the microgrid system to malfunction. Physical connection line failures may have a significant impact on the stability, reliability and security of the microgrid and may lead to serious consequences. b. Generator tripping fault: Damage to internal components of the generator, poor circuit connection, or harsh external environment can lead to a decline in generator performance or even failure to operate normally. Generator failure may result in insufficient power supply to the microgrid system, equipment damage or shutdown, affecting the normal operation of the entire microgrid group; c. Load loss fault: In a microgrid, some loads may suddenly disappear due to equipment failure, intentional damage, misoperation, etc. Load loss faults will cause voltage and frequency fluctuations in the microgrid, overcurrent or overvoltage of operating equipment, thereby affecting its stable operation, and even causing the microgrid group to collapse. d. Communication line failure: Communication lines between the various sub-microgrids in a microgrid cluster may experience interruptions, delays, or errors during information transmission. Communication failures may affect information exchange and coordinated control between the various sub-microgrids, leading to control abnormalities in the overall microgrid or some microgrids in the microgrid cluster. The causes of communication failures may include unreasonable network topology, damaged hardware, incompatible communication protocols, and mismatched communication frequencies.

3. The microgrid group flexible interconnection and coordinated control method adaptable to multiple types of faults according to claim 2, characterized in that, The specific steps for determining the fault type in step (3) are as follows: a. Transmission line or flexible interconnection device faults: By analyzing data collected through the real-time power grid monitoring system, information such as the phase, voltage, and current of the fault is obtained, and digital signal processing and pattern recognition technologies are used to locate the line fault; b. Generator tripping fault: Real-time monitoring software installed on the microgrid management system is used to monitor and analyze the generator output power, current, and voltage parameters in the microgrid group in real time. If any abnormality occurs, a warning or fault information will be displayed. c. Load power failure: By installing real-time monitoring software on the microgrid management system, the electrical parameters in the microgrid group are monitored and analyzed in real time, including system voltage, current and power indicators. When a certain indicator suddenly changes or exceeds the preset range, it is determined that there may be a load power failure. d. Communication line faults: The real-time monitoring software installed on the microgrid management system can monitor and analyze the communication lines within the microgrid group in real time. When a communication line is abnormal or interrupted, the software will issue a warning or fault information.

4. The microgrid group flexible interconnection coordinated control method adaptable to multiple types of faults according to claim 1, characterized in that, In step (3), based on the fault type determination result, flexible interconnection and coordinated control of the microgrid group is implemented, specifically including: For transmission line or flexible interconnection device faults between microgrids and generator tripping faults within microgrids, control objectives and constraints are formulated for these faults. The control objectives are solved, and the flexible interconnection coordination control of microgrid groups under the two fault scenarios is achieved by optimizing the allocation of adjustable resources and load adjustment within the microgrid. For load power failure faults in microgrids, control objectives and constraints for load power failure faults are formulated, control objectives are solved, and flexible interconnection and coordinated control of microgrid groups under this fault condition is achieved by optimizing the allocation of adjustable resources in the microgrid. To address communication line faults between microgrids, control objectives and constraints for communication line faults are formulated, and the control objectives are solved to achieve flexible interconnection and coordinated control of the microgrid group under such fault conditions.

5. The microgrid group flexible interconnection coordinated control method adaptable to multiple types of faults according to claim 4, characterized in that, For faults in transmission lines or flexible interconnection devices between microgrids and generator tripping faults within microgrids, control objectives and constraints are formulated, specifically as follows: （20）； In the formula, Indicates the first Taiwan's available resources Indicates the first The output cost of Taiwan's adjustable resources Indicates the first Adjustment requirements for the load capacity of the platform. This represents the power loss penalty coefficient, indicating the cost of power loss for the load. There are a total of 5 constraints for the control method, the first of which is the power balance equation: （21）； The second constraint is the generator output power constraint: （22）； The third constraint is the load requirement constraint: （23）； The fourth constraint is the load adjustment amount constraint: （24）； The fifth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids: （25）； In the formula, Indicates the first Taiwan's available resources and They represent the first Minimum and maximum limits on the output of Taiwan's adjustable resources. Indicates the first The output cost of Taiwan's adjustable resources Indicates the first The demand for desktop load, and These represent the minimum and maximum demand for the load, respectively. This indicates the capacity of the transmission lines or flexible interconnection devices between microgrids. and These represent transmission power and reactive power, respectively. Indicates the first Adjustment requirements for the load capacity of the platform. and These represent the minimum and maximum values ​​of the load adjustment, respectively. This represents the power loss penalty coefficient, indicating the cost of power loss for the load. By solving the above control objectives, and considering the impact of transmission line or flexible interconnection device faults between microgrids and generator tripping faults within the microgrid, we can find the adjustable resource output allocation scheme that minimizes the total cost, thereby achieving coordinated control of flexible interconnection of microgrid groups.

6. The microgrid group flexible interconnection coordinated control method adaptable to multiple types of faults according to claim 4, characterized in that, For load power failure faults within a microgrid, control objectives and constraints for load power failure faults are formulated, specifically as follows: （26）； In the formula, Indicates the first Taiwan's available resources Indicates the first The output cost of Taiwan's adjustable resources; There are four constraints in the control method, the first of which is the power balance equation: （27）； The second constraint is the generator output power constraint: （28）； The third constraint is the load requirement constraint: （29）； The fourth constraint is the capacity constraint of transmission lines or flexible interconnection devices between microgrids: （30）； In the formula, Indicates the first Taiwan's available resources and They represent the first Minimum and maximum limits on the output of Taiwan's adjustable resources. Indicates the first The output cost of Taiwan's adjustable resources Indicates the first The demand for desktop load, and These represent the minimum and maximum demand for the load, respectively. This indicates the capacity of the transmission lines or flexible interconnection devices between microgrids. and These represent transmission power and reactive power, respectively. By solving the above control objectives, we can consider the impact of load power failures on the microgrid and find the adjustable resource output allocation scheme that minimizes the total cost, thereby realizing flexible interconnection and coordinated control of the microgrid group.

7. The microgrid group flexible interconnection coordinated control method adaptable to multiple types of faults according to claim 4, characterized in that, For load power failure faults within a microgrid, control objectives and constraints for load power failure faults are formulated, specifically as follows: The first control objective is: （31）； The second goal is: （32）； in These are the eigenvalues ​​of matrix A; The second objective is also expressed as （33）； The constraints of the control method specifically include: Laplace matrix constraints for communication networks: （34）； （35）； （36）； in, It is the element in the upper right corner of the Laplace matrix of the communication network. It refers to the number of communication links; When solving for the control objective of communication line faults, the control method integrates two optimization objectives together, namely... （37）； in, It is a comprehensive optimization objective function. and These are two positive numbers controlling the proportion of two optimization objectives. The objectives are added together to construct the optimization model; a penalty function is used to handle the constraints. （38）； in, It is the ultimate optimization goal; , and It is a positive number that controls the degree of penalty function of the constraint condition. h(y) is a function. When y>0, h(y)=0, and when y≤0, h(y)=1. g(y) is a function. When y=0, g(y)=0, and when y≠0, g(y)=1.

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