A hybrid microgrid group power coordination control method and device

Abstract

The present invention discloses a hybrid microgrid group power coordination control method and device, the method comprising: establishing a hybrid microgrid group topology structure; each AC subnet collects the bus frequency of the corresponding AC bus, and each DC subnet collects the bus voltage of the corresponding DC bus; when the bus frequency of the AC subnet, or the bus voltage of the DC subnet fluctuates within a first preset range, the AC subnet and the DC subnet adopt adaptive droop control to achieve power coordination; when the bus frequency of the AC subnet, or the bus voltage of the DC subnet fluctuates within a second preset range, the AC subnet and the DC subnet achieve power coordination by exchanging power; when the bus frequency of the AC subnet, or the bus voltage of the DC subnet fluctuates beyond the second preset range, controlling the power output of the energy storage subnet to achieve power coordination. This method can improve the robustness of the system.

Description

Technical Field

[0001] The present invention relates to the field of microgrid control technology, and in particular to a hybrid microgrid group power coordination control method and device. Background Art

[0002] To improve the reliability of AC / DC hybrid microgrid power supply, multiple adjacent AC and DC subgrids are often interconnected to form an AC / DC hybrid microgrid cluster to power the load. However, the stable operation of such isolated hybrid microgrid clusters depends entirely on reasonable power interaction management strategies between subgrids and the output control methods of distributed power sources. Therefore, in-depth research on power management strategies for hybrid microgrid clusters is necessary.

[0003] At present, there have been a lot of research on the power management strategy of hybrid microgrid groups operating in isolated islands. However, the current research results are based on isolated AC microgrid groups, which cannot meet the working conditions of AC and DC hybrid power supply. In addition, the power management of isolated hybrid microgrid groups focuses on achieving the mutual support effect of power between sub-microgrids, ignoring the independent autonomous operation capability of sub-microgrids. The hybrid microgrid groups studied in the existing research only contain a single AC and a single DC subgrid, and the control is relatively simple. When the hybrid microgrid group contains more different subgrids, its coordinated control will become more complicated. For example, the patent text CN111740426B discloses a power collaborative control method for isolated AC / DC hybrid microgrid groups, including: for DC sub-microgrids with constant power loads, A V2-P droop control strategy was constructed. A SOC dynamic balance consistency control strategy was constructed for the energy storage sub-microgrid. A sub-microgrid power exchange control strategy was constructed for the DC, AC, and energy storage sub-microgrids. A communication triggering control strategy was constructed based on the sub-microgrid power exchange control strategy. The output power of the DC, energy storage, and AC sub-microgrids was controlled using the V2-P droop control strategy, the SOC dynamic balance consistency control strategy, and the traditional Pf droop control strategy. The sub-microgrid power exchange control strategy and communication triggering control strategy were applied to the isolated AC / DC hybrid microgrid cluster to control power exchange and interconnection communication between the sub-microgrids. However, this method suffers from complex control strategies and is not very reliable in practical applications. Summary of the Invention

[0004] The present invention provides a hybrid microgrid group power coordinated control method and device, which can effectively improve the reliability of hybrid microgrid group power coordinated control.

[0005] A hybrid microgrid group power coordination control method, comprising:

[0006] Establishing a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes multiple AC subgrids, DC subgrids, and energy storage subgrids;

[0007] Each of the AC subnets collects the bus frequency of the corresponding AC bus, and each of the DC subnets collects the bus voltage of the corresponding DC bus;

[0008] When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range, the AC subnet and the DC subnet adopt adaptive droop control to achieve power coordination;

[0009] When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a second preset range, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet exchange power through the AC subnet interactive power and the DC subnet interactive power to achieve power coordination;

[0010] When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, an adaptive adjustment coefficient is calculated based on the common bus voltage, a droop control coefficient is calculated based on the state of the energy storage unit, and the power output of the energy storage subnet is controlled according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination.

[0011] Furthermore, the distributed power supply in the AC subnet is connected to the corresponding AC bus through an AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through a DC / DC converter, the AC bus is connected to the common bus through an AC / DC converter, the DC bus is connected to the common bus through a DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through a DC / DC converter.

[0012] Furthermore, the AC subnet adopts adaptive droop control to achieve power coordination, including:

[0013] Calculating a frequency change of the AC subnet within a first preset time period according to the bus frequency;

[0014] Calculating a frequency correction droop coefficient of the AC subnet based on the frequency change, the first preset duration, the rated frequency of the AC subnet, and a preset frequency correction parameter;

[0015] Calculating a droop control coefficient of the AC subnet based on the frequency correction droop coefficient, the frequency upper limit value of the AC subnet, the frequency lower limit value of the AC subnet, and the upper limit value of the output power of the AC subnet;

[0016] Calculate the target output frequency of the AC subnet based on the droop control coefficient of the AC subnet, the actual output power of the DC subnet, and the upper frequency limit of the AC subnet;

[0017] The frequency output of the AC subnet is controlled according to the calculated target output frequency.

[0018] Furthermore, the DC subnet adopts adaptive droop control to achieve power coordination, including:

[0019] Calculating a voltage change of the DC subnet within a second preset time period based on the bus voltage;

[0020] Calculating a voltage correction droop coefficient of the DC subnet according to the voltage variation, the second preset time duration, the rated voltage of the DC subnet, and a preset voltage correction parameter;

[0021] Calculating a droop control coefficient of the DC subnet based on the voltage correction droop coefficient, the voltage upper limit of the DC subnet, the voltage lower limit of the DC subnet, and the upper limit of the DC subnet output power;

[0022] Calculate the target voltage of the DC subnetwork based on the droop control coefficient of the DC subnetwork, the actual output power of the DC subnetwork, and the voltage upper limit of the DC subnetwork;

[0023] The voltage output of the DC subnetwork is controlled according to the calculated target voltage.

[0024] Furthermore, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet exchange power through the AC subnet interactive power and the DC subnet interactive power to achieve power coordination, including:

[0025] Establish an objective function with the lowest bus frequency deviation of the AC subnet and the lowest bus voltage deviation of the DC subnet;

[0026] Construct power conservation constraints for the AC and DC subnets, frequency constraints for the AC subnets, and voltage constraints for the DC subnets;

[0027] Based on the MFO algorithm, the AC subgrid interaction power and the DC subgrid interaction power that satisfy the objective function, the AC subgrid and DC subgrid power conservation constraints, the AC subgrid frequency constraints, and the DC subgrid voltage constraints are calculated;

[0028] The output power of the corresponding AC subgrid and DC subgrid is controlled according to the calculated AC subgrid interactive power and DC subgrid interactive power.

[0029] Furthermore, an adaptive adjustment coefficient is calculated according to the common bus voltage, a droop control coefficient is calculated according to the state of the energy storage unit, and the power output of the energy storage subnetwork is controlled according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination, including:

[0030] Collect common bus voltage;

[0031] Calculating a rate of change of the common bus voltage over time based on the common bus voltage;

[0032] Calculating an adaptive adjustment coefficient based on the common bus voltage and the rate of change of the common bus voltage over time;

[0033] Detecting the state of charge and maximum output power of the energy storage unit, and calculating a droop control coefficient of the power output of the energy storage subnet based on the state of charge and the maximum output power;

[0034] Calculating the output power of the energy storage subgrid based on the common bus voltage, the adaptive adjustment coefficient, and the droop control coefficient of the energy storage subgrid power output;

[0035] Collect the bus voltage of the energy storage unit;

[0036] Performing current calculation based on the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current;

[0037] Inputting the energy storage unit exchange current into a PI controller for calculation, and outputting the energy storage unit target voltage;

[0038] The target voltage of the energy storage unit is PWM modulated to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

[0039] Furthermore, calculating an adaptive adjustment coefficient according to the common bus voltage and the rate of change of the common bus voltage over time includes:

[0040] Comparing the common bus voltage with a preset voltage threshold, when the common bus voltage is less than or equal to the preset voltage threshold, the adaptive adjustment coefficient is 1;

[0041] When the common bus voltage is greater than the preset voltage threshold, the adaptive adjustment coefficient is calculated according to a hyperbolic tangent function value of a rate of change of the common bus voltage over time.

[0042] Furthermore, the droop control coefficient of the energy storage subgrid power output is calculated using the following formula:

[0043] ;

[0044] Among them, b k represents the droop control coefficient of the energy storage subgrid power output, k O represents the parameter for adjusting the droop coefficient, μ represents the parameter for adjusting the SOC balancing speed of each energy storage unit, and P ds，k Indicates the maximum output power of the kth energy storage unit, SOC kIt represents the current state of charge of the kth energy storage unit, and SOC* represents the reference state of charge value given by the battery standard of each energy storage unit.

[0045] A hybrid microgrid group power coordination control device, comprising:

[0046] A topology building module is used to establish a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes multiple AC subgrids, DC subgrids and energy storage subgrids;

[0047] A frequency acquisition module, each of the AC subnets acquires the bus frequency of the corresponding AC bus through the frequency acquisition module;

[0048] A voltage acquisition module, each of the DC subnets acquires the bus voltage of the corresponding DC bus through the voltage acquisition module;

[0049] an adaptive droop control module, configured to control the AC subnet and the DC subnet to adopt adaptive droop control to achieve power coordination when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range;

[0050] a power interaction control module, configured to calculate the AC subnetwork interaction power and the DC subnetwork interaction power based on the MFO algorithm when the bus frequency of the AC subnetwork or the bus voltage of the DC subnetwork fluctuates within a second preset range, and control the AC subnetwork and the DC subnetwork to exchange power through the AC subnetwork interaction power and the DC subnetwork interaction power to achieve power coordination;

[0051] The energy storage control module is used to calculate an adaptive adjustment coefficient based on the common bus voltage and a droop control coefficient based on the state of the energy storage unit when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, and to control the power output of the energy storage subnet according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination.

[0052] Furthermore, the distributed power supply in the AC subnet is connected to the corresponding AC bus through an AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through a DC / DC converter, the AC bus is connected to the common bus through an AC / DC converter, the DC bus is connected to the common bus through a DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through a DC / DC converter.

[0053] Furthermore, the AC subnet adopts adaptive droop control to achieve power coordination, including:

[0054] Calculating a frequency change of the AC subnet within a first preset time period according to the bus frequency;

[0055] Calculating a frequency correction droop coefficient of the AC subnet based on the frequency change, the first preset duration, the rated frequency of the AC subnet, and a preset frequency correction parameter;

[0056] Calculating a droop control coefficient of the AC subnet based on the frequency correction droop coefficient, the frequency upper limit value of the AC subnet, the frequency lower limit value of the AC subnet, and the upper limit value of the output power of the AC subnet;

[0057] Calculate the target output frequency of the AC subnet based on the droop control coefficient of the AC subnet, the actual output power of the DC subnet, and the upper frequency limit of the AC subnet;

[0058] The frequency output of the AC subnet is controlled according to the calculated target output frequency.

[0059] Furthermore, the DC subnet adopts adaptive droop control to achieve power coordination, including:

[0060] Calculating a voltage change of the DC subnet within a second preset time period based on the bus voltage;

[0061] Calculating a voltage correction droop coefficient of the DC subnet according to the voltage variation, the second preset time duration, the rated voltage of the DC subnet, and a preset voltage correction parameter;

[0062] Calculating a droop control coefficient of the DC subnet based on the voltage correction droop coefficient, the voltage upper limit of the DC subnet, the voltage lower limit of the DC subnet, and the upper limit of the DC subnet output power;

[0063] Calculate the target voltage of the DC subnetwork based on the droop control coefficient of the DC subnetwork, the actual output power of the DC subnetwork, and the voltage upper limit of the DC subnetwork;

[0064] The voltage output of the DC subnetwork is controlled according to the calculated target voltage.

[0065] Furthermore, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet perform power exchange to achieve power coordination through the AC subnet interactive power and the DC subnet interactive power, including:

[0066] Establish an objective function with the lowest bus frequency deviation of the AC subnet and the lowest bus voltage deviation of the DC subnet;

[0067] Construct power conservation constraints for the AC and DC subnets, frequency constraints for the AC subnets, and voltage constraints for the DC subnets;

[0068] Based on the MFO algorithm, the AC subgrid interaction power and the DC subgrid interaction power that satisfy the objective function, the AC subgrid and DC subgrid power conservation constraints, the AC subgrid frequency constraints, and the DC subgrid voltage constraints are calculated;

[0069] The output power of the corresponding AC subgrid and DC subgrid is controlled according to the calculated AC subgrid interactive power and DC subgrid interactive power.

[0070] Furthermore, the energy storage control module calculates an adaptive adjustment coefficient according to the common bus voltage, calculates a droop control coefficient according to the state of the energy storage unit, and controls the power output of the energy storage subnet according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination, including:

[0071] Collect common bus voltage;

[0072] Calculating a rate of change of the common bus voltage over time based on the common bus voltage;

[0073] Calculating an adaptive adjustment coefficient based on the common bus voltage and the rate of change of the common bus voltage over time;

[0074] Detecting the state of charge and maximum output power of the energy storage unit, and calculating a droop control coefficient of the power output of the energy storage subnet based on the state of charge and the maximum output power;

[0075] Calculating the output power of the energy storage subgrid based on the common bus voltage, the adaptive adjustment coefficient, and the droop control coefficient of the energy storage subgrid power output;

[0076] Collect the bus voltage of the energy storage unit;

[0077] Performing current calculation based on the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current;

[0078] Inputting the energy storage unit exchange current into a PI controller for calculation, and outputting the energy storage unit target voltage;

[0079] The target voltage of the energy storage unit is PWM modulated to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

[0080] Furthermore, the energy storage control module calculates an adaptive adjustment coefficient according to the common bus voltage and the rate of change of the common bus voltage over time, including:

[0081] Comparing the common bus voltage with a preset voltage threshold, when the common bus voltage is less than or equal to the preset voltage threshold, the adaptive adjustment coefficient is 1;

[0082] When the common bus voltage is greater than the preset voltage threshold, the adaptive adjustment coefficient is calculated according to a hyperbolic tangent function value of a rate of change of the common bus voltage over time.

[0083] Furthermore, the droop control coefficient of the energy storage subgrid power output is calculated using the following formula:

[0084] ;

[0085] Among them, b k represents the droop control coefficient of the energy storage subgrid power output, k O represents the parameter for adjusting the droop coefficient, μ represents the parameter for adjusting the SOC balancing speed of each energy storage unit, and P ds，k Indicates the maximum output power of the kth energy storage unit, SOC k It represents the current state of charge of the kth energy storage unit, and SOC* represents the reference state of charge value given by the battery standard of each energy storage unit.

[0086] An electronic device includes a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is used to read the instructions and execute the above method.

[0087] The hybrid microgrid group power coordination control method and device provided by the present invention have at least the following beneficial effects:

[0088] (1) Under different frequency and voltage fluctuation conditions, a power management strategy consisting of subgrid power autonomous control, inter-subgrid power interaction support, and energy storage unit power balance is adopted. Through coordinated control among the three layers, the power supply reliability and quality of the isolated AC / DC hybrid microgrid group are improved, and reasonable power management is achieved among the distributed power sources within the hybrid microgrid group, among the sub-microgrids with different distributed power sources capacities and power quality requirements, and among the energy storage units. This method is still applicable in the event of communication failures and has good robustness.

[0089] (2) The AC and DC subgrids use adaptive droop control to achieve power coordination. Frequency and voltage variations are introduced into the droop control coefficients. Droop control is performed based on frequency and voltage variations to achieve rapid and stable control of frequency and voltage.

[0090] (3) Using the MFO algorithm to calculate the interaction power between the AC subgrid and the DC subgrid can obtain a better global optimal solution and improve the reliability of the coordinated power control of the AC subgrid and the DC subgrid;

[0091] (4) In the process of controlling the power output of the energy storage subgrid, an adaptive adjustment coefficient is introduced. When the common bus voltage is higher than the preset voltage threshold, the adaptive adjustment parameter takes effect. When the rate of change of the common bus voltage over time increases, the adaptive adjustment coefficient becomes larger, thereby improving the system inertia capability and suppressing further deterioration of the voltage. When the rate of change of the common bus voltage over time is in a recovery state, the adaptive adjustment coefficient is reduced to reduce the inertia, thereby shortening the time for the voltage to recover and stabilize. By using the hyperbolic tangent function, the adjustment coefficient can be smoothly and quickly selected autonomously according to the degree of voltage deviation, and the whole process is continuous adjustment without obvious step process, which is more friendly to the inner loop control of the microgrid converter and achieves no obvious voltage distortion in the microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] Figure 1 This is a flow chart of an embodiment of the hybrid microgrid group power coordination control method provided by the present invention.

[0093] Figure 2 This is a schematic diagram of an embodiment of a hybrid microgrid group topology structure in the hybrid microgrid group power coordination control method provided by the present invention.

[0094] Figure 3 The present invention provides a flow chart of an embodiment of the hybrid microgrid group power coordination control method in which the AC subnet uses adaptive droop control to achieve power coordination.

[0095] Figure 4 The present invention provides a flow chart of an embodiment of a hybrid microgrid group power coordination control method in which a DC subnet uses adaptive droop control to achieve power coordination.

[0096] Figure 5 The present invention provides a flow chart of an embodiment of a hybrid microgrid group power coordination control method in which an AC subnet or a DC subnet realizes power coordination by exchanging power.

[0097] Figure 6 The present invention provides a flow chart of an embodiment of achieving power coordination by the power output of the energy storage subnet in the power coordination control method of the hybrid microgrid group.

[0098] Figure 7 This is a structural diagram of an embodiment of a hybrid microgrid group power coordination control device provided by the present invention. DETAILED DESCRIPTION

[0099] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0100] refer to Figure 1In some embodiments, a hybrid microgrid group power coordination control method is provided, comprising:

[0101] S1. Establishing a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes multiple AC subgrids, DC subgrids, and energy storage subgrids;

[0102] S2. Each of the AC subnets collects the bus frequency of the corresponding AC bus, and each of the DC subnets collects the bus voltage of the corresponding DC bus;

[0103] S3: When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range, the AC subnet and the DC subnet adopt adaptive droop control to achieve power coordination;

[0104] S4. When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a second preset range, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet exchange power through the AC subnet interactive power and the DC subnet interactive power to achieve power coordination;

[0105] S5. When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, an adaptive adjustment coefficient is calculated based on the common bus voltage, and a droop control coefficient is calculated based on the state of the energy storage unit. The power output of the energy storage subnet is controlled according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination.

[0106] Further, refer to Figure 2 In step S1, the hybrid microgrid group topology is established as follows: Figure 2 As shown, the distributed power supply in the AC subnet is connected to the corresponding AC bus through the AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through the DC / DC converter, the AC bus is connected to the common bus through the AC / DC converter, the DC bus is connected to the common bus through the DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through the DC / DC converter.

[0107] Furthermore, in step S2, each of the AC subnets collects the bus frequency of the corresponding AC bus, and each of the DC subnets collects the bus voltage of the corresponding DC bus, as a judgment basis and calculation basis for subsequent coordinated control.

[0108] Furthermore, in step S3, when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range, the AC subnet and the DC subnet adopt adaptive droop control to achieve power coordination, wherein the first preset range may be less than 10%, that is, when the bus frequency of the AC subnet fluctuates less than 10%, or when the bus voltage of the DC subnet fluctuates less than 10%, adaptive droop control is adopted to achieve power coordination, and the control timing is in seconds.

[0109] Specifically, refer to Figure 3 In step S3, the AC subnet adopts adaptive droop control to achieve power coordination, including:

[0110] S31. Calculating a frequency change of the AC subnet within a first preset time period based on the bus frequency;

[0111] S32. Calculating a frequency correction droop coefficient of the AC subnet based on the frequency change, the first preset duration, the rated frequency of the AC subnet, and a preset frequency correction parameter;

[0112] S33, calculating the droop control coefficient of the AC subnet according to the frequency correction droop coefficient, the upper frequency limit of the AC subnet, the lower frequency limit of the AC subnet, and the upper limit of the output power of the AC subnet;

[0113] S34. Calculate the target output frequency of the AC subnet based on the droop control coefficient of the AC subnet, the actual output power of the AC subnet, and the upper frequency limit of the AC subnet;

[0114] S35. Control the frequency output of the AC subnet according to the calculated target output frequency.

[0115] Specifically, in step S31, the change Δt1 of the bus frequency of the AC subnet is calculated according to the first preset time length Δt2. f .

[0116] In step S32, according to the frequency change Δ f , the first preset duration △t1, AC subnet rated frequency f n and the preset frequency correction parameter k f , calculate the frequency correction droop coefficient of the AC subnet u fix , the specific calculation formula is:

[0117] ; (1)

[0118] Among them, △ f Indicates the frequency change, △t1 indicates the first preset time length, f NIndicates the rated frequency of the AC subnet, k f Indicates the preset frequency correction parameters, u fix Indicates the frequency correction droop coefficient of the AC subnet.

[0119] Furthermore, in step S33, the droop coefficient is corrected according to the frequency u fix , the upper frequency limit of the AC subnet f max , the lower frequency limit of the AC subnet f min , the upper limit of the AC subnet output power , calculate the droop control coefficient u of the AC subnet. The specific calculation formula is:

[0120] ; (2)

[0121] in, u fix represents the frequency correction droop coefficient, f max Indicates the upper frequency limit of the AC subnet. f min Indicates the lower frequency limit of the AC subnet, It represents the upper limit of the AC subnet output power, and u represents the droop control coefficient of the AC subnet.

[0122] Furthermore, in step S34, according to the droop control coefficient u of the AC subnet and the actual output power P of the AC subnet, ac and the upper frequency limit of the AC subnet f max , calculate the target output frequency of the AC subnet f , the calculation formula is as follows:

[0123] ; (3)

[0124] Where u represents the droop control coefficient of the AC subnet, P ac Indicates the actual output power of the AC subnet. f max Indicates the upper frequency limit of the AC subnet. f Indicates the target output frequency of the AC subnet.

[0125] Furthermore, in step S35, a corresponding control signal is generated according to the target output frequency obtained by calculation to control the frequency output of the AC subnet.

[0126] Further, refer to Figure 4 In step S3, the DC subnet adopts adaptive droop control to achieve power coordination, including:

[0127] S3A. Calculating a voltage change of the DC subnet within a second preset time period based on the bus voltage;

[0128] S3B, calculating a voltage correction droop coefficient of the DC subnet based on the voltage variation, the second preset duration, the DC subnet rated voltage, and a preset voltage correction parameter;

[0129] S3C. Calculating a droop control coefficient of the DC subnet based on the voltage correction droop coefficient, the DC subnet voltage upper limit, the DC subnet voltage lower limit, and the DC subnet output power upper limit;

[0130] S3D, calculate the target voltage of the DC subnet based on the droop control coefficient of the DC subnet, the actual output power of the DC subnet, and the voltage upper limit of the DC subnet;

[0131] S3E. Control the voltage output of the DC subnet according to the calculated target voltage.

[0132] Specifically, in step S3A, the voltage variation of the DC subnet within the second preset time Δt2 is ΔV dc .

[0133] Furthermore, in step S3B, according to the voltage change ΔV dc , the second preset time length △t2, the DC subnet rated voltage V dcN and the preset voltage correction parameter k v , calculate the voltage correction droop coefficient w of the DC subnet fix , the calculation formula is as follows:

[0134] ; (4)

[0135] Among them, △V dc represents the voltage change, △t2 represents the second preset time, V dcN Indicates the rated voltage of the DC subnet, k v Indicates the preset voltage correction parameter, w fix Indicates the voltage correction droop coefficient of the DC subnetwork.

[0136] Furthermore, in step S3C, the droop coefficient w is corrected according to the voltage fix , the upper voltage limit of the DC subnet , DC subnet voltage lower limit , the upper limit of the DC subnet output power , calculate the droop control coefficient w of the DC subnetwork, the calculation formula is as follows:

[0137] ; (5)

[0138] Among them, wfix Indicates the voltage correction droop coefficient, Indicates the upper voltage limit of the DC subnet. Indicates the lower voltage limit of the DC subnet. It represents the upper limit of the DC sub-grid output power, and w represents the droop control coefficient of the DC sub-grid.

[0139] Furthermore, in step S3D, according to the droop control coefficient w of the DC subnet and the actual output power P of the DC subnet, dc and the upper voltage limit of the DC subnet , calculate the target voltage V of the DC subnet dc , the calculation formula is as follows:

[0140] ; (6)

[0141] Where w represents the droop control coefficient of the DC subnetwork, P dc Indicates the actual output power of the DC subnet, Indicates the upper voltage limit of the DC subnet, V dc Indicates the target voltage of the DC subnetwork.

[0142] Furthermore, in step S3E, a corresponding control signal is generated according to the calculated target voltage to control the voltage output of the DC subnet.

[0143] When the bus frequency of the AC subgrid or the bus voltage of the DC subgrid fluctuates within the first preset range, the distributed power sources in each subgrid realize autonomous power coordination within the subgrid through adaptive correction droop control. The droop coefficient can be adaptively corrected according to the frequency change rate of the AC subgrid and the voltage change rate of the DC subgrid, thereby realizing rapid and stable control of frequency and voltage and maintaining subgrid power autonomy.

[0144] Further, refer to Figure 5 In step S4, when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a second preset range, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet exchange power through the AC subnet interactive power and the DC subnet interactive power to achieve power coordination, specifically including:

[0145] S41, establishing an objective function to minimize the bus frequency deviation of the AC subnet and the bus voltage deviation of the DC subnet;

[0146] S42. Construct power conservation constraints for the AC subnet and the DC subnet, frequency constraints for the AC subnet, and voltage constraints for the DC subnet;

[0147] S43. Calculate, based on the MFO algorithm, the AC subnetwork interaction power and the DC subnetwork interaction power that satisfy the objective function, the AC subnetwork and DC subnetwork power conservation constraints, the AC subnetwork frequency constraints, and the DC subnetwork voltage constraints;

[0148] S44. Control the output power of the corresponding AC subnet and DC subnet according to the calculated AC subnet interactive power and DC subnet interactive power.

[0149] Specifically, in step S41, an objective function is established to minimize the bus frequency deviation of the AC subnet and the bus voltage deviation of the DC subnet, which specifically includes:

[0150] ; (7)

[0151] ; (8)

[0152] ; (9)

[0153] in, f i represents the actual output frequency of the ith AC subnet, n represents the number of AC subnets, f N Indicates the rated frequency of the AC subnet. F1 indicates that the bus frequency deviation of the AC subnet is the lowest. Indicates the actual voltage of the ith DC subnet, V dcN represents the rated voltage of the DC subnet, m represents the number of DC subnets, F2 represents the lowest bus voltage deviation of the DC subnet, and F represents the objective function.

[0154] Furthermore, in step S42, the power conservation constraints of the AC sub-grid and the DC sub-grid are as follows:

[0155] ; (10)

[0156] ; (11)

[0157] Where n represents the number of AC subnets, m represents the number of DC subnets, represents the interaction power of the ith AC subnet, represents the interaction power of the ith DC subnetwork, represents the interactive reactive power of the i-th AC subnetwork.

[0158] Furthermore, the AC subnet frequency constraints are as follows:

[0159] ; (12)

[0160] in, Respectively represent the frequency difference of each AC subnet, Indicates the maximum frequency deviation threshold of the AC subnet.

[0161] Furthermore, the DC subnet voltage constraints are as follows:

[0162] ; (13)

[0163] in, Represents the voltage difference of each DC subnet, Indicates the maximum voltage deviation threshold of the DC subnet.

[0164] Furthermore, in step S43, based on the MFO algorithm, the AC subgrid interaction power and the DC subgrid interaction power that satisfy the objective function, the AC subgrid and DC subgrid power conservation constraints, the AC subgrid frequency constraints, and the DC subgrid voltage constraints are calculated, including:

[0165] S431. Using the power conservation constraints of the AC subnet and the DC subnet, the frequency constraints of the AC subnet, and the voltage constraints of the DC subnet as boundary conditions, a search space is constructed;

[0166] S432. Randomly generate initial values of the AC subnet interaction power and the DC subnet interaction power in the search space as moths;

[0167] S433, calculating the fitness of the moth based on the objective function;

[0168] S434, sorting the moths in descending order according to their fitness, and selecting a preset number of moths with the highest order as flames;

[0169] S435. In each iteration, the moth approaches the flame along the spiral flight path and calculates the fitness, updates the flame according to the fitness, and updates the spiral flight path until the stopping condition is met and the optimal solution is output.

[0170] Moth-Flame Optimization (MFO) is a nature-inspired optimization algorithm proposed by S. Mirjalili in 2015. The algorithm simulates the behavior of moths flying around a light source at night, which exhibits a spiral trajectory, similar to the phenomenon of moths flying into flames. The core idea of the MFO algorithm is to simulate the spiral path of a moth flying around a light source (a flame), where the "moth" represents possible solutions and the "flame" represents the current optimal solution. By continuously updating the moth's position to approach the flame, the algorithm gradually finds the global optimal solution.

[0171] When the bus frequency of the AC subgrid or the bus voltage of the DC subgrid fluctuates within the second preset range, a multi-objective optimization algorithm is used to achieve the lowest frequency deviation of the AC subgrid and the lowest voltage deviation of the DC subgrid, and with the constraints of power conservation, frequency, and voltage operation within the limits of the subgrid group, an AC / DC hybrid microgrid multi-objective optimization control model is constructed. The interaction power P of each AC / DC microgrid is obtained through the moth-to-flame optimization algorithm. ea 、P ed , where P ea It represents the power exchanged between the AC subnet and the public bus, that is, the interactive support power, P ed = represents the power exchanged between the DC subgrid and the common bus. Here, the interactive support is defined as positive for power flowing into the subgrid and negative for power flowing out of the subgrid. This layer of control design provides key control parameters for the power electronic converters (AC / DC and DC / DC) in each AC / DC subgrid, enabling optimized power scheduling between AC and DC microgrids.

[0172] Further, refer to Figure 6 In step S5, an adaptive adjustment coefficient is calculated according to the common bus voltage, a droop control coefficient is calculated according to the state of the energy storage unit, and the power output of the energy storage subnet is controlled according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination, including:

[0173] S51, collecting common bus voltage;

[0174] S52. Calculating a rate of change of the common bus voltage over time based on the common bus voltage;

[0175] S53, calculating an adaptive adjustment coefficient according to the common bus voltage and the rate of change of the common bus voltage over time;

[0176] S54, detecting the state of charge and maximum output power of the energy storage unit, and calculating a droop control coefficient of the power output of the energy storage subnet according to the state of charge and the maximum output power;

[0177] S55. Calculate the output power of the energy storage subnetwork according to the common bus voltage, the adaptive adjustment coefficient, and the droop control coefficient of the energy storage subnetwork power output;

[0178] S56, collecting the bus voltage of the energy storage unit;

[0179] S57, performing current calculation according to the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current;

[0180] S58, inputting the energy storage unit exchange current into a PI controller for calculation, and outputting a target voltage of the energy storage unit;

[0181] S59: Perform PWM modulation on the target voltage of the energy storage unit to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

[0182] Specifically, in step S52, the rate of change of the common bus voltage over time is the differential of the common bus voltage with respect to time, that is, , where V cb Indicates the common bus voltage.

[0183] Furthermore, in step S53, the adaptive adjustment coefficient is calculated according to the common bus voltage and the rate of change of the common bus voltage over time, including:

[0184] Comparing the common bus voltage with a preset voltage threshold, when the common bus voltage is less than or equal to the preset voltage threshold, the adaptive adjustment coefficient is 1;

[0185] When the common bus voltage is greater than the preset voltage threshold, the adaptive adjustment coefficient is calculated according to a hyperbolic tangent function value of a rate of change of the common bus voltage over time.

[0186] Specifically, when the common bus voltage is greater than the preset voltage threshold and the rate of change of the common bus voltage over time is greater than 0, the adaptive adjustment coefficient is the sum of a hyperbolic tangent function value of the product of the rate of change of the common bus voltage over time and the corresponding adjustment rate and 1;

[0187] When the common bus voltage is greater than the preset voltage threshold and the rate of change of the common bus voltage over time is less than 0, the adaptive adjustment coefficient is the difference between 1 and the hyperbolic tangent function value of the product of the rate of change of the common bus voltage over time and the corresponding adjustment rate.

[0188] Specifically, the adaptive adjustment coefficient is calculated using the following formula:

[0189] ; (14)

[0190] Among them, a k is the adaptive adjustment coefficient, V cb Indicates the common bus voltage, m1 and m2 are the adjustment rate setting values, which can be adjusted according to the control requirements. V cbN Indicates the preset voltage threshold.

[0191] When the common bus voltage is below a preset voltage threshold, the hybrid microgrid common bus voltage deviation is acceptable. Adaptive adjustment parameters only take effect when the common bus voltage is above this threshold. As the rate of change of the common bus voltage increases over time, the adaptive adjustment coefficient increases, improving the system's inertia and suppressing further voltage deterioration. When the rate of change of the common bus voltage over time is recovering, the adaptive adjustment coefficient decreases, reducing inertia and shortening the time it takes for the voltage to stabilize.

[0192] By using the hyperbolic tangent function, the adjustment coefficient can be smoothly and quickly selected independently according to the degree of voltage deviation. The entire process is continuous adjustment without obvious step process. It is more friendly to the inner loop control of the microgrid converter and achieves no obvious voltage distortion in the microgrid.

[0193] Furthermore, in step S54, the droop control coefficient of the energy storage subgrid power output is calculated using the following formula:

[0194] ;

[0195] Among them, b k represents the droop control coefficient of the energy storage subgrid power output, k O represents the parameter for adjusting the droop coefficient, μ represents the parameter for adjusting the SOC balancing speed of each energy storage unit, and P ds，k Indicates the maximum output power of the kth energy storage unit, SOC k It represents the current state of charge of the kth energy storage unit, and SOC* represents the reference state of charge value given by the battery standard of each energy storage unit.

[0196] Furthermore, in step S55, the output power of the energy storage subnet is calculated according to the common bus voltage, the adaptive adjustment coefficient and the droop control coefficient of the energy storage subnet power output. The calculation formula is as follows:

[0197] ;

[0198] Among them, P ds，k represents the output power of the energy storage subnet, b k represents the droop control coefficient of the energy storage subgrid power output, a k is the adaptive adjustment coefficient, V cb Indicates the common bus voltage.

[0199] Furthermore, after calculating and obtaining the output power of the energy storage subnet, the bus voltage of the energy storage unit is collected, and the current is calculated based on the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current; the energy storage unit exchange current is input into the PI controller for calculation, and the target voltage of the energy storage unit is output; the target voltage of the energy storage unit is PWM modulated to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

[0200] refer to Figure 7 In some embodiments, a hybrid microgrid group power coordination control device is provided, comprising:

[0201] A topology building module 201 is configured to establish a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes a plurality of AC subgrids, DC subgrids, and energy storage subgrids;

[0202] A frequency acquisition module 202, each of the AC subnets acquires the bus frequency of the corresponding AC bus through the frequency acquisition module;

[0203] A voltage acquisition module 203 is used for each DC subnet to acquire the bus voltage of the corresponding DC bus;

[0204] An adaptive droop control module 204 is configured to control the AC subnet and the DC subnet to implement power coordination using adaptive droop control when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range;

[0205] The power interaction control module 205 is configured to calculate the AC subnetwork interaction power and the DC subnetwork interaction power based on the MFO algorithm when the bus frequency of the AC subnetwork or the bus voltage of the DC subnetwork fluctuates within a second preset range, and control the AC subnetwork and the DC subnetwork to exchange power through the AC subnetwork interaction power and the DC subnetwork interaction power to achieve power coordination;

[0206] The energy storage control module 206 is used to calculate an adaptive adjustment coefficient based on the common bus voltage and a droop control coefficient based on the state of the energy storage unit when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, and to control the power output of the energy storage subnet according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination.

[0207] Furthermore, the distributed power supply in the AC subnet is connected to the corresponding AC bus through an AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through a DC / DC converter, the AC bus is connected to the common bus through an AC / DC converter, the DC bus is connected to the common bus through a DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through a DC / DC converter.

[0208] Furthermore, the AC subnet adopts adaptive droop control to achieve power coordination, including:

[0209] Calculating a frequency change of the AC subnet within a first preset time period according to the bus frequency;

[0210] Calculating a frequency correction droop coefficient of the AC subnet based on the frequency change, the first preset duration, the rated frequency of the AC subnet, and a preset frequency correction parameter;

[0211] Calculating a droop control coefficient of the AC subnet based on the frequency correction droop coefficient, the frequency upper limit value of the AC subnet, the frequency lower limit value of the AC subnet, and the upper limit value of the output power of the AC subnet;

[0212] Calculate the target output frequency of the AC subnet based on the droop control coefficient of the AC subnet, the actual output power of the DC subnet, and the upper frequency limit of the AC subnet;

[0213] The frequency output of the AC subnet is controlled according to the calculated target output frequency.

[0214] Furthermore, the DC subnet adopts adaptive droop control to achieve power coordination, including:

[0215] Calculating a voltage change of the DC subnet within a second preset time period based on the bus voltage;

[0216] Calculating a voltage correction droop coefficient of the DC subnet according to the voltage variation, the second preset time duration, the rated voltage of the DC subnet, and a preset voltage correction parameter;

[0217] Calculating a droop control coefficient of the DC subnet based on the voltage correction droop coefficient, the voltage upper limit of the DC subnet, the voltage lower limit of the DC subnet, and the upper limit of the DC subnet output power;

[0218] Calculate the target voltage of the DC subnetwork based on the droop control coefficient of the DC subnetwork, the actual output power of the DC subnetwork, and the voltage upper limit of the DC subnetwork;

[0219] The voltage output of the DC subnetwork is controlled according to the calculated target voltage.

[0220] Furthermore, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet perform power exchange to achieve power coordination through the AC subnet interactive power and the DC subnet interactive power, including:

[0221] Establish an objective function with the lowest bus frequency deviation of the AC subnet and the lowest bus voltage deviation of the DC subnet;

[0222] Construct power conservation constraints for the AC and DC subnets, frequency constraints for the AC subnets, and voltage constraints for the DC subnets;

[0223] Based on the MFO algorithm, the AC subgrid interaction power and the DC subgrid interaction power that satisfy the objective function, the AC subgrid and DC subgrid power conservation constraints, the AC subgrid frequency constraints, and the DC subgrid voltage constraints are calculated;

[0224] The output power of the corresponding AC subgrid and DC subgrid is controlled according to the calculated AC subgrid interactive power and DC subgrid interactive power.

[0225] Furthermore, the energy storage control module calculates an adaptive adjustment coefficient according to the common bus voltage, calculates a droop control coefficient according to the state of the energy storage unit, and controls the power output of the energy storage subnet according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination, including:

[0226] Collect common bus voltage;

[0227] Calculating a rate of change of the common bus voltage over time based on the common bus voltage;

[0228] Calculating an adaptive adjustment coefficient based on the common bus voltage and the rate of change of the common bus voltage over time;

[0229] Detecting the state of charge and maximum output power of the energy storage unit, and calculating a droop control coefficient of the power output of the energy storage subnet based on the state of charge and the maximum output power;

[0230] Calculating the output power of the energy storage subgrid based on the common bus voltage, the adaptive adjustment coefficient, and the droop control coefficient of the energy storage subgrid power output;

[0231] Collect the bus voltage of the energy storage unit;

[0232] Performing current calculation based on the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current;

[0233] Inputting the energy storage unit exchange current into a PI controller for calculation, and outputting the energy storage unit target voltage;

[0234] The target voltage of the energy storage unit is PWM modulated to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

[0235] Furthermore, the energy storage control module calculates an adaptive adjustment coefficient according to the common bus voltage and the rate of change of the common bus voltage over time, including:

[0236] Comparing the common bus voltage with a preset voltage threshold, when the common bus voltage is less than or equal to the preset voltage threshold, the adaptive adjustment coefficient is 1;

[0237] When the common bus voltage is greater than the preset voltage threshold, the adaptive adjustment coefficient is calculated according to a hyperbolic tangent function value of a rate of change of the common bus voltage over time.

[0238] Furthermore, the droop control coefficient of the energy storage subgrid power output is calculated using the following formula:

[0239] ;

[0240] Among them, b k represents the droop control coefficient of the energy storage subgrid power output, k O represents the parameter for adjusting the droop coefficient, μ represents the parameter for adjusting the SOC balancing speed of each energy storage unit, and P ds，k Indicates the maximum output power of the kth energy storage unit, SOC k It represents the current state of charge of the kth energy storage unit, and SOC* represents the reference state of charge value given by the battery standard of each energy storage unit.

[0241] In some embodiments, an electronic device is also provided, including a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is configured to read the instructions and execute the above method.

[0242] The hybrid microgrid group power coordination control method and device provided by the above embodiment have at least the following beneficial effects:

[0243] (1) Under different frequency and voltage fluctuation conditions, a power management strategy consisting of subgrid power autonomous control, inter-subgrid power interaction support, and energy storage unit power balance is adopted. Through coordinated control among the three layers, the power supply reliability and quality of the isolated AC / DC hybrid microgrid group are improved, and reasonable power management is achieved among the distributed power sources within the hybrid microgrid group, among the sub-microgrids with different distributed power sources capacities and power quality requirements, and among the energy storage units. This method is still applicable in the event of communication failures and has good robustness.

[0244] (2) The AC and DC subgrids use adaptive droop control to achieve power coordination. Frequency and voltage variations are introduced into the droop control coefficients. Droop control is performed based on frequency and voltage variations to achieve rapid and stable control of frequency and voltage.

[0245] (3) Using the MFO algorithm to calculate the interaction power between the AC subgrid and the DC subgrid can obtain a better global optimal solution and improve the reliability of the coordinated power control of the AC subgrid and the DC subgrid;

[0246] (4) In the process of controlling the power output of the energy storage subgrid, an adaptive adjustment coefficient is introduced. When the common bus voltage is higher than the preset voltage threshold, the adaptive adjustment parameter takes effect. When the rate of change of the common bus voltage over time increases, the adaptive adjustment coefficient becomes larger, thereby improving the system inertia capability and suppressing further deterioration of the voltage. When the rate of change of the common bus voltage over time is in a recovery state, the adaptive adjustment coefficient is reduced to reduce the inertia, thereby shortening the time for the voltage to recover and stabilize. By using the hyperbolic tangent function, the adjustment coefficient can be smoothly and quickly selected autonomously according to the degree of voltage deviation, and the whole process is continuous adjustment without obvious step process, which is more friendly to the inner loop control of the microgrid converter and achieves no obvious voltage distortion in the microgrid.

[0247] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the invention. Thus, the present invention is intended to include such changes and modifications as fall within the scope of the claims and their equivalents.

Claims

1. A hybrid microgrid group power coordination control method, characterized in that: include: Establishing a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes multiple AC subgrids, DC subgrids, and energy storage subgrids; Each of the AC subnets collects the bus frequency of the corresponding AC bus, and each of the DC subnets collects the bus voltage of the corresponding DC bus; When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range, the AC subnet and the DC subnet adopt adaptive droop control to achieve power coordination; When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a second preset range, the AC subnet interactive power and the DC subnet interactive power are calculated based on the MFO algorithm, and the AC subnet and the DC subnet exchange power through the AC subnet interactive power and the DC subnet interactive power to achieve power coordination; When the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, an adaptive adjustment coefficient is calculated based on the common bus voltage, a droop control coefficient is calculated based on the state of the energy storage unit, and the power output of the energy storage subnet is controlled according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination; The distributed power supply in the AC subnet is connected to the corresponding AC bus through an AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through a DC / DC converter, the AC bus is connected to the common bus through an AC / DC converter, the DC bus is connected to the common bus through a DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through a DC / DC converter.

2. The method according to claim 1, characterized in that The AC subnetwork adopts adaptive droop control to achieve power coordination, including: Calculating a frequency change of the AC subnet within a first preset time period according to the bus frequency; Calculating a frequency correction droop coefficient of the AC subnet based on the frequency change, the first preset duration, the rated frequency of the AC subnet, and a preset frequency correction parameter; Calculating a droop control coefficient of the AC subnet based on the frequency correction droop coefficient, the frequency upper limit value of the AC subnet, the frequency lower limit value of the AC subnet, and the upper limit value of the output power of the AC subnet; Calculate the target output frequency of the AC subnet based on the droop control coefficient of the AC subnet, the actual output power of the AC subnet, and the upper frequency limit of the AC subnet; The frequency output of the AC subnet is controlled according to the calculated target output frequency.

3. The method according to claim 1, characterized in that The DC subgrid adopts adaptive droop control to achieve power coordination, including: Calculating a voltage change of the DC subnet within a second preset time period based on the bus voltage; Calculating a voltage correction droop coefficient of the DC subnet according to the voltage variation, the second preset time duration, the rated voltage of the DC subnet, and a preset voltage correction parameter; Calculating a droop control coefficient of the DC subnet based on the voltage correction droop coefficient, the voltage upper limit of the DC subnet, the voltage lower limit of the DC subnet, and the upper limit of the DC subnet output power; Calculate the target voltage of the DC subnetwork based on the droop control coefficient of the DC subnetwork, the actual output power of the DC subnetwork, and the voltage upper limit of the DC subnetwork; The voltage output of the DC subnetwork is controlled according to the calculated target voltage.

4. The method according to claim 1, wherein Calculating the AC subnet interactive power and the DC subnet interactive power based on the MFO algorithm, wherein the AC subnet and the DC subnet exchange power to achieve power coordination through the AC subnet interactive power and the DC subnet interactive power, including: Establish an objective function with the lowest bus frequency deviation of the AC subnet and the lowest bus voltage deviation of the DC subnet; Construct power conservation constraints for the AC and DC subnets, frequency constraints for the AC subnets, and voltage constraints for the DC subnets; Based on the MFO algorithm, the AC subgrid interaction power and the DC subgrid interaction power that satisfy the objective function, the AC subgrid and DC subgrid power conservation constraints, the AC subgrid frequency constraints, and the DC subgrid voltage constraints are calculated; The output power of the corresponding AC subgrid and DC subgrid is controlled according to the calculated AC subgrid interactive power and DC subgrid interactive power.

5. The method according to claim 1, characterized in that Calculating an adaptive adjustment coefficient according to the common bus voltage, calculating a droop control coefficient according to the state of the energy storage unit, and controlling the power output of the energy storage subgrid according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination, including: Collect common bus voltage; Calculating a rate of change of the common bus voltage over time based on the common bus voltage; Calculating an adaptive adjustment coefficient based on the common bus voltage and the rate of change of the common bus voltage over time; Detecting the state of charge and maximum output power of the energy storage unit, and calculating a droop control coefficient of the power output of the energy storage subnet based on the state of charge and the maximum output power; Calculating the output power of the energy storage subgrid based on the common bus voltage, the adaptive adjustment coefficient, and the droop control coefficient of the energy storage subgrid power output; Collect the bus voltage of the energy storage unit; Performing current calculation based on the output power of the energy storage subnet and the bus voltage of the energy storage unit to obtain the energy storage unit exchange current; Inputting the energy storage unit exchange current into a PI controller for calculation, and outputting the energy storage unit target voltage; The target voltage of the energy storage unit is PWM modulated to generate a power exchange control signal to control the corresponding DC / DC converter to perform power exchange.

6. The method according to claim 5, characterized in that Calculating an adaptive adjustment coefficient according to the common bus voltage and a rate of change of the common bus voltage over time includes: Comparing the common bus voltage with a preset voltage threshold, when the common bus voltage is less than or equal to the preset voltage threshold, the adaptive adjustment coefficient is 1; When the common bus voltage is greater than the preset voltage threshold, the adaptive adjustment coefficient is calculated according to a hyperbolic tangent function value of a rate of change of the common bus voltage over time.

7. The method according to claim 5, characterized in that The droop control coefficient of the energy storage subgrid power output is calculated using the following formula: ； Among them, b k represents the droop control coefficient of the energy storage subgrid power output, k O It represents the parameter for adjusting the droop coefficient, μ represents the parameter for adjusting the SOC balancing speed of each energy storage unit, Indicates the maximum output power of the kth energy storage unit, SOC k Indicates the current state of charge of the kth energy storage unit, SOC * Indicates the reference state of charge value given by the battery standard of each energy storage unit.

8. A hybrid microgrid group power coordination control device, characterized in that: include: A topology building module, configured to establish a hybrid microgrid group topology structure, wherein the hybrid microgrid group topology includes a plurality of AC subgrids, a DC subgrid, and an energy storage subgrid; A frequency acquisition module, each of the AC subnets acquires the bus frequency of the corresponding AC bus through the frequency acquisition module; A voltage acquisition module, each of the DC subnets acquires the bus voltage of the corresponding DC bus through the voltage acquisition module; an adaptive droop control module, configured to control the AC subnet and the DC subnet to adopt adaptive droop control to achieve power coordination when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates within a first preset range; a power interaction control module, configured to calculate the AC subnetwork interaction power and the DC subnetwork interaction power based on the MFO algorithm when the bus frequency of the AC subnetwork or the bus voltage of the DC subnetwork fluctuates within a second preset range, and control the AC subnetwork and the DC subnetwork to exchange power through the AC subnetwork interaction power and the DC subnetwork interaction power to achieve power coordination; an energy storage control module configured to calculate an adaptive adjustment coefficient based on the common bus voltage and a droop control coefficient based on the state of the energy storage unit when the bus frequency of the AC subnet or the bus voltage of the DC subnet fluctuates beyond a second preset range, and to control the power output of the energy storage subnet according to the adaptive adjustment coefficient and the droop control coefficient to achieve power coordination; The distributed power supply in the AC subnet is connected to the corresponding AC bus through an AC / AC converter, the distributed power supply in the DC subnet is connected to the corresponding DC bus through a DC / DC converter, the AC bus is connected to the common bus through an AC / DC converter, the DC bus is connected to the common bus through a DC / DC converter, and the energy storage unit in the energy storage subnet is connected to the common bus through a DC / DC converter.

9. An electronic device, characterized in that: The method comprises a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is configured to read the instructions and execute the method according to any one of claims 1 to 7.

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