Energy storage cross-regional collaborative AGC (Automatic Gain Control) optimization control method and equipment considering conditional SOC (State of Charge) equalization

Abstract

The invention discloses an energy storage cross-regional cooperation AGC optimization control method and equipment considering conditional SOC equalization, and the method comprises the steps: firstly evaluating the equivalent charge state and dynamic frequency modulation capability of an energy storage system in each region in real time, and judging whether a cross-regional cooperation condition is satisfied or not; if yes, a multi-objective optimization model is established, and the model takes a plurality of objective functions as optimization objectives, including enabling the equivalent state of charge to be balanced, minimizing inter-region tie line transmission power and maximizing the residual frequency modulation capability, and meanwhile, takes power grid operation parameters as constraint conditions. And by solving the model, obtaining an optimal output instruction of the energy storage system in each region in the next AGC control period, and issuing the optimal output instruction to the corresponding energy storage system for execution. The invention aims to support other regions through the tie line when the frequency modulation margin of the energy storage system in the interconnected region is sufficient, avoid frequency fluctuation caused by over-limit of the energy storage SOC and insufficient frequency modulation of a thermal power generating unit, improve the safety and reliability of energy storage frequency modulation, effectively stabilize the frequency fluctuation of a power grid, and enhance the anti-disturbance capability of a power system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of energy storage regulation and optimal control, in particular to an AGC optimal control method and device for energy storage cross-regional cooperation considering conditional SOC balancing. BACKGROUND

[0002] With the transformation of energy structure and large-scale access of renewable energy, the proportion of new energy power system in total power generation is increasing. The inherent characteristics of new energy generation (such as wind energy and solar energy) result in fluctuation and uncertainty of its output power, which brings problems to the supply and demand balance and frequency stability of the power system. In the traditional power system, the frequency regulation task of the power grid mainly depends on conventional power sources such as thermal power units, which adjust their output to respond to changes in system frequency. With the continuous increase of new energy installed capacity, the frequency regulation capacity of a single regional power grid is difficult to effectively cope with the complex supply and demand imbalance problem caused by new energy fluctuations. In this case, the role of energy storage system in grid frequency regulation is highlighted due to its fast response capability and bidirectional regulation characteristics.

[0003] At present, the application of energy storage system in the power grid is mostly limited to a single region, and the output allocation is carried out through the automatic generation control (AGC) system. However, the traditional single-region AGC control strategy has limitations. Specifically, this strategy only allocates output based on the initial energy of the energy storage unit, without fully considering the dynamic change characteristics of the battery energy, such as the real-time change of SOC (State of Charge). This static allocation method cannot achieve the optimal configuration of the energy storage unit, which may cause the energy storage device to continue charging and discharging when the SOC reaches the upper or lower limit, thereby causing overcharging / overdischarging, shortening the service life of the device, and even threatening the safe and stable operation of the power grid. In addition, the energy storage power stations in different regional power grids may have different frequency regulation capabilities due to different initial SOC states. Unreasonable power allocation may further exacerbate this imbalance, causing some energy storage units to still bear the frequency regulation task when the SOC reaches the limit, while other regional energy storage units are idle due to insufficient utilization of the frequency regulation margin. The traditional solution usually monitors the real-time value of the energy storage SOC and limits the output of the energy storage system or prioritizes SOC recovery when it reaches or approaches the upper and lower limits of the SOC, but these methods often cannot balance the system's frequency regulation output demand. SUMMARY

[0004] In view of the problems in the prior art, the application provides an AGC optimization control method and equipment for energy storage cross-regional cooperation considering conditional SOC balancing, which aims to make interconnected regional energy storage systems transfer power through tie lines to support other regional energy storage systems when there is frequency modulation margin, avoid the problems of insufficient output of energy storage SOC out of limit and insufficient frequency fluctuation caused by insufficient frequency modulation output of energy storage to thermal power units, improve the safety and reliability of energy storage cross-regional participation in frequency modulation, effectively suppress power grid frequency fluctuation, and enhance the anti-disturbance ability of the power system.

[0005] In order to solve the above technical problems, the application is implemented by the following technical solutions: According to a first aspect of the application, an AGC optimization control method for energy storage cross-regional cooperation considering conditional SOC balancing is provided, comprising: real-time evaluation of the state of each regional energy storage system, the state including the equivalent state of charge of the regional energy storage system and the dynamic frequency modulation capability of the regional energy storage system; based on the equivalent state of charge and the dynamic frequency modulation capability, determining whether the preset cross-regional cooperation necessary condition is met; when the result of the determination is that at least one of the cross-regional cooperation necessary conditions is met, a multi-objective optimization model is established with multiple target functions as optimization objectives and power grid operation parameters as constraint conditions, and the multi-objective optimization model is solved to obtain optimal output instructions of each regional energy storage system in the next AGC control period; wherein the multiple target functions at least include: a first target function for making the equivalent state of charge of each regional energy storage system tend to be balanced, a second target function for minimizing the transmission power of the inter-regional tie line, and a third target function for maximizing the remaining frequency modulation capability of each regional energy storage system after meeting the local frequency modulation demand; the optimal output instructions are issued to the corresponding regional energy storage system for execution.

[0006] In a possible implementation manner of the first aspect, the evaluation of the equivalent state of charge of the regional energy storage system is specifically:

[0007] wherein, is the equivalent state of charge of the regional energy storage system at the moment; is the equivalent state of charge of the regional energy storage system at the moment; is the rated capacity of the energy storage power station; is the rated capacity of the energy storage power station; is the state of charge of the energy storage power station at the moment; is the state of charge of the energy storage power station at the moment;

[0008] In a possible implementation manner of the first aspect, the evaluation of the dynamic frequency modulation capability of the regional energy storage system is specifically: Define the continuous charge-discharge capability of energy storage for 1 minute, and use the continuous charge-discharge capability to measure the dynamic frequency regulation capability: , In the formula, For the region Energy storage capacity for 1 minute of continuous charging and discharging; For energy storage capacity; This represents the maximum energy storage capacity. This represents the minimum energy storage capacity. This is the rated output power for energy storage; For the region The area control error signal; Considering the ramp rate and capacity constraints of the energy storage unit, the modified DAA, which characterizes the maximum support that the energy storage can provide in the next AGC control cycle, is defined as: , In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; , They are respectively The upper and lower limits of the actual output of the energy storage system at any time; for Real-time active power of the energy storage system; The instruction cycle of the AGC system; , These are the rated up-rate and rated down-rate of the energy storage system, respectively.

[0009] In one possible implementation of the first aspect, the necessary condition for cross-regional collaboration includes at least one of the following conditions: Condition 1: The equivalent state of charge of the regional energy storage system exceeds the preset safe operating range of the regional energy storage system, specifically:

[0010]

[0011] In the formula, for Time zone Equivalent state of charge of the medium-capacity energy storage system; The upper limit of the safe operating range preset for regional energy storage systems; The lower limit of the safe operating range preset for regional energy storage systems; Condition 2: The equivalent state of charge (SBC) of the regional energy storage system is within the preset warning range, and the current direction of the active power output of the regional energy storage system will cause the SBC of the regional energy storage system to change in a direction closer to the boundary of the safe operating range, specifically:

[0012]

[0013] In the formula, This is the preset upper limit of the warning range; This is the preset lower limit of the warning range; For the region Inside The output power of the battery energy storage system at all times; Condition 3: The dynamic frequency regulation capability of the regional energy storage system is less than the current local frequency regulation requirement of the regional energy storage system, specifically:

[0014] In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system.

[0015] In one possible implementation of the first aspect, the first objective function is constructed to minimize the variance of the equivalent state of charge of the energy storage system in each region during the next AGC control cycle, specifically:

[0016]

[0017]

[0018] In the formula, This indicates the region of the next AGC control cycle after the energy storage system output changes. Equivalent state of charge of an energy storage system; express time The mean of the equivalent state of charge of the energy storage system in each region; To indicate the duration of the AGC control cycle; This indicates the output of the energy storage system in the next AGC control cycle; For the region Rated capacity of medium-sized energy storage.

[0019] In one possible implementation of the first aspect, the second objective function is constructed to minimize the total power and power variation on the inter-regional interconnects in the next AGC control cycle, specifically:

[0020]

[0021] In the formula, , They represent Time zone Total power and total power change on the connection lines between other regions and Representing regions With the region Frequency deviation; This is the synchronous torque coefficient; The number of regions in the interconnected power grid; For the Laplace operator.

[0022] In one possible implementation of the first aspect, the third objective function is constructed to maximize the remaining real-time frequency regulation capability of each regional energy storage system after meeting local frequency regulation requirements in the next AGC control cycle, specifically as follows:

[0023] In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; For the region Inside The output power of the battery energy storage system at any time.

[0024] In one possible implementation of the first aspect, the constraints include: upper and lower limits of energy storage system output, real-time frequency regulation capability of energy storage system, state of charge of energy storage system, tie line transmission power, system power balance, and necessary conditions for cross-regional coordination. The necessary constraints for cross-regional collaboration include: The constraint corresponding to condition one is:

[0025] In the formula, , The 0-1 auxiliary variables are introduced; These are relaxation parameters; The number of regions in the interconnected power grid; Indicates the area Whether energy storage participates in the collaboration, Indicates the area Energy storage participates in collaboration, Indicates the area Energy storage does not participate in the collaboration; The constraint corresponding to condition two is:

[0026] In the formula, , , For the introduced 0-1 auxiliary variables, These are relaxation parameters; The constraint corresponding to condition three is:

[0027] In the formula, This is an auxiliary variable consisting of 0 and 1.

[0028] According to a second aspect of the present invention, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the aforementioned AGC optimization control method for cross-regional energy storage considering conditional SOC equalization.

[0029] According to a third aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing a computer program, which, when executed by a processor, implements the aforementioned AGC optimization control method for cross-regional energy storage coordination considering conditional SOC balance.

[0030] Compared with the prior art, the present invention has at least the following beneficial effects: This invention provides an AGC optimization control method for cross-regional energy storage collaboration considering SOC balance. By real-time evaluation of the equivalent state of charge (SOC) and dynamic frequency regulation capability of energy storage systems in each region, and under the condition of cross-regional collaboration, an optimization model is established with equivalent SOC balance as the objective. This promotes the consistency of SOC states among energy storage systems in each region during frequency regulation, thereby avoiding forced charging and discharging of some energy storage units even when their SOC reaches its limit. This effectively prevents overcharging or over-discharging, extends the service life of energy storage equipment, and ensures operational safety. Employing a collaborative strategy aimed at minimizing tie-line transmission power and maximizing the remaining frequency regulation capability of each region, the method can rationally allocate frequency regulation tasks among multiple regions, fully utilize the frequency regulation potential of energy storage systems in each region, and avoid the problem of some regions' energy storage exiting frequency regulation due to excessively high or low SOC, while other regions' energy storage resources are not effectively utilized. This achieves efficient configuration of the overall frequency regulation capability of the energy storage system. By establishing a multi-objective optimization model and solving for the optimal output command, cross-regional power support is achieved using tie lines while meeting local frequency regulation requirements. This alleviates the problem of insufficient frequency regulation capacity in a single region, effectively suppresses frequency fluctuations caused by renewable energy fluctuations, and improves the frequency stability and anti-interference capability of the power system under complex operating conditions. This invention introduces a conditional SOC equalization mechanism and multi-objective collaborative optimization, enabling the dynamic maintenance of the energy storage system within a reasonable operating range while meeting the system's frequency regulation output requirements. This overcomes the problem of balancing frequency regulation performance and energy storage protection in traditional methods.

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a flowchart of the method of the present invention.

[0034] Figure 2 This is a schematic diagram of a three-region calculation example of the present invention.

[0035] Figure 3 This is a schematic diagram of the collaborative optimization control strategy process of the present invention.

[0036] Figure 4 This is a schematic diagram of the cross-regional collaborative optimization strategy for energy storage of the present invention.

[0037] Figure 5 This is a schematic diagram of the Pareto front of the present invention.

[0038] Figure 6 This is a comparison of the energy storage SOC before and after optimization in simulation A of this invention.

[0039] Figure 7 This is a comparison of the power exchange of the tie lines before and after optimization in simulation A of this invention.

[0040] Figure 8 This is a schematic diagram of 0-1 decision variables for energy storage coordination under the simulation of optimization A in this invention.

[0041] Figure 9 This is a schematic diagram showing the energy storage output and the change in energy storage output before and after optimization A in the simulation of this invention.

[0042] Figure 10 This is a comparison of the energy storage SOC before and after optimization in simulation B of this invention.

[0043] Figure 11 This invention provides a comparison of the power exchange of the tie line before and after optimization B in simulation.

[0044] Figure 12 This is a schematic diagram of 0-1 decision variables for energy storage coordination under the B-optimization effect of the present invention.

[0045] Figure 13 This is a schematic diagram showing the energy storage output and the change in energy storage output before and after optimization B in the simulation of this invention.

[0046] Figure 14 This is a schematic diagram of the energy storage SOC under long-term operation of the present invention.

[0047] Figure 15 This is a schematic diagram showing the changes in energy storage output in each region and the 0-1 decision variables under the optimization effect of this invention.

[0048] Figure 16 This is a schematic diagram illustrating the changes in tie-line power exchange during long-term operation of the present invention. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] like Figure 1 As shown, this invention provides an AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance, comprising the following steps: Step 1: Real-time assessment of the status of energy storage systems in each region, including the equivalent state of charge and the dynamic frequency regulation capability of the regional energy storage systems.

[0051] In other words, this step involves real-time monitoring and evaluation of the status of energy storage systems in each region. The evaluated status mainly includes two aspects: The equivalent state of charge (SOC) of a regional energy storage system is used to comprehensively reflect the average charge level of all energy storage units within the region. The equivalent SOC value for the region is obtained by weighted averaging of the real-time SOC of each energy storage unit within the region.

[0052] In one possible implementation, the assessment of the equivalent state of charge of the regional energy storage system specifically involves:

[0053] In the formula, for In the time-regional power grid The equivalent state of charge of an energy storage power station; For energy storage power stations Rated capacity; for Real-time energy storage power station The state of charge (SOC) is defined as the ratio of the remaining capacity of the energy storage system to its rated capacity. Its value range is [0,1]. An SOC value of 1 indicates that the current battery energy storage system is fully charged, and an SOC value of 0 indicates that the energy storage system is fully discharged.

[0054] The dynamic frequency regulation capability of a regional energy storage system is used to characterize the power regulation capability of a regional energy storage system in response to changes in grid frequency under the current state.

[0055] In one possible implementation, the assessment of the dynamic frequency regulation capability of the regional energy storage system specifically involves: Define the continuous charge-discharge capability of energy storage for 1 minute, and use the continuous charge-discharge capability to measure the dynamic frequency regulation capability: , In the formula, For the region Energy storage capacity for 1 minute of continuous charging and discharging; For energy storage capacity; This represents the maximum energy storage capacity. This represents the minimum energy storage capacity. This is the rated output power for energy storage; For the region The area control error signal; Considering the ramp rate and capacity constraints of the energy storage unit, the modified DAA, which characterizes the maximum support that the energy storage can provide in the next AGC control cycle, is defined as: , In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; , They are respectively The upper and lower limits of the actual output of the energy storage system at any time; for Real-time active power of the energy storage system; The instruction cycle of the AGC system; , These are the rated up-rate and rated down-rate of the energy storage system, respectively.

[0056] Step 2: Based on the equivalent state of charge and the dynamic frequency modulation capability, determine whether the preset necessary conditions for cross-regional coordination are met.

[0057] In one possible implementation, the necessary conditions for cross-regional collaboration include at least one of the following conditions: Condition 1: The equivalent state of charge of the regional energy storage system exceeds the preset safe operating range of the regional energy storage system. Exceeding this range requires coordination. Specifically:

[0058]

[0059] In the formula, for Time zone Equivalent state of charge of the medium-capacity energy storage system; The upper limit of the safe operating range preset for regional energy storage systems; The lower limit of the safe operating range preset for regional energy storage systems.

[0060] Condition 2: The equivalent state of charge (SBC) of the regional energy storage system is within the preset warning range, and the current direction of the active power output of the regional energy storage system will cause the SBC of the regional energy storage system to change in a direction closer to the boundary of the safe operating range, specifically:

[0061]

[0062] In the formula, This is the preset upper limit of the warning range; This is the preset lower limit of the warning range; For the region Inside The output power of the battery energy storage system at any time.

[0063] In other words, when the current energy storage output may worsen the State of Charge (SOC), coordination is needed.

[0064] Condition 3: The dynamic frequency regulation capability of the regional energy storage system is less than the current local frequency regulation requirement of the regional energy storage system, specifically:

[0065] In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system.

[0066] If the energy storage currently satisfies this formula, it indicates that the current frequency regulation capability of the energy storage is insufficient, and cross-regional coordination is required.

[0067] Step 3: When the judgment result satisfies at least one of the necessary conditions for cross-regional coordination, establish a multi-objective optimization model with multiple objective functions as optimization objectives and grid operation parameters as constraints, and solve the multi-objective optimization model to obtain the optimal output command of each regional energy storage system in the next AGC control cycle; wherein, the multiple objective functions include at least: a first objective function for balancing the equivalent state of charge of each regional energy storage system, a second objective function for minimizing the transmission power of inter-regional tie lines, and a third objective function for maximizing the remaining frequency regulation capacity of each regional energy storage system after meeting local frequency regulation requirements.

[0068] In other words, this step is initiated when the judgment result of step 2 indicates that the coordination condition is met. First, a multi-objective optimization model is established, which includes multiple optimization objectives and the actual constraints of power grid operation.

[0069] The optimization objectives mainly include: the first objective function, which aims to promote the equilibrium of the equivalent state of charge of the energy storage systems in the participating regions.

[0070] In this embodiment, the first objective function is constructed to minimize the variance of the equivalent state of charge of the energy storage system in each region during the next AGC control cycle, specifically:

[0071]

[0072]

[0073] In the formula, This indicates the region of the next AGC control cycle after the energy storage system output changes. Equivalent state of charge of an energy storage system; express time The mean of the equivalent state of charge of the energy storage system in each region; To indicate the duration of the AGC control cycle; This indicates the output of the energy storage system in the next AGC control cycle; For the region Rated capacity of medium-sized energy storage.

[0074] The second objective function is to minimize the transmission power of inter-regional tie lines. Under the premise of meeting frequency modulation requirements and SOC equalization, the power transmitted through tie lines should be reduced as much as possible to reduce network loss.

[0075] In this embodiment, the second objective function is constructed to minimize the total power and power change on the inter-regional interconnects in the next AGC control cycle, specifically:

[0076]

[0077] In the formula, , They represent Time zone Total power and total power change on the connection lines between other regions and Representing regions With the region Frequency deviation; This is the synchronous torque coefficient; The number of regions in the interconnected power grid; For the Laplace operator.

[0078] In interconnected power systems, power transmission via tie lines results in active power loss. Power transmission should be avoided as much as possible when it is not necessary. Therefore, an objective function is set to minimize the power transmitted on the tie lines.

[0079] The third objective function is to maximize the remaining frequency regulation capacity of each regional energy storage system after meeting its local basic frequency regulation needs. Through optimization, each regional energy storage system can still maintain a significant frequency regulation margin to cope with potential frequency fluctuations after completing its current collaborative tasks.

[0080] In this embodiment, the third objective function is constructed to maximize the remaining real-time frequency regulation capability of each region's energy storage system after meeting local frequency regulation requirements in the next AGC control cycle, specifically:

[0081] In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; For the region Inside The output power of the battery energy storage system at any time.

[0082] Since the energy storage frequency regulation capacity is limited, cross-regional coordination is required only on the basis of ensuring sufficient capacity for frequency regulation in the local area. Therefore, an objective function is set to maximize the remaining real-time frequency regulation capacity after meeting the energy storage participation frequency regulation output requirements in a future AGC cycle.

[0083] In one feasible approach, the constraints include: upper and lower limits of energy storage system output, real-time frequency regulation capability of energy storage system, state of charge of energy storage system, tie-line transmission power, system power balance, and necessary conditions for cross-regional coordination, as specifically expressed below: Energy storage output upper and lower limits constraints: , In the formula, Rated charge and discharge power for energy storage; Constraints on real-time frequency regulation capability of energy storage: , SOC constraints: , Tether line transmission power constraints: , In the formula, Indicates the maximum limit for power transmission on the tie line; Power balance constraints: , , In the formula, This refers to the conversion of the mechanical power output of the steam turbine. This refers to the change in output power of the energy storage system. This refers to the change in the output power of the photovoltaic system. This represents the change in active power caused by changes in system load. During optimization, changes in energy storage output are transmitted through tie lines, ensuring that they do not affect the output of other units and maintaining power balance.

[0084] The necessary constraints for cross-regional collaboration include: The constraint corresponding to condition one is:

[0085] In the formula, , The 0-1 auxiliary variables are introduced; To set the relaxation parameter, take a sufficiently large positive number; The number of regions in the interconnected power grid. Indicates the area Whether energy storage participates in the collaboration, Indicates the area Energy storage participates in collaboration, Indicates the area Energy storage does not participate in the collaboration; The constraint corresponding to condition two is:

[0086] In the formula, , , For the introduced 0-1 auxiliary variables, , All are relaxation parameters. Take a sufficiently large positive number. Take a sufficiently small positive number; The constraint corresponding to condition three is:

[0087] In the formula, The 0-1 auxiliary variables are introduced; The relaxation parameter is a sufficiently small positive number.

[0088] Step 4: The optimal output command is sent to the corresponding regional energy storage system for execution. Specifically, the optimal output command obtained in Step 3 is sent to the corresponding regional energy storage system controllers through the power grid dispatch data network. After receiving the command, each regional energy storage system performs charging and discharging operations according to its specified power value, jointly completing the frequency regulation task of the power grid.

[0089] In one feasible approach, the Pareto optimality method is used to solve the multi-objective optimization model to obtain a Pareto optimal solution set consisting of multiple non-dominated solutions; and the entropy weight method is used to select the solution with the highest comprehensive score from the Pareto optimal solution set as the optimal output command.

[0090] Example Step 1. To verify the performance advantages of the proposed AGC optimization control strategy for cross-regional energy storage considering SOC balance, a system is established. Figure 2The three-region interconnected power grid model shown was simulated and verified using the MATLAB / Simu-link platform. The model parameters of each AGC unit in the three regions are shown in Tables 1 and 2, and the constraint parameters set during optimization are shown in Table 3. The rated frequency of the power grid is 50Hz, and the rated capacity is 1000MW. To reflect the auxiliary output of energy storage, a small-capacity energy storage was selected in each regional power grid with parameters of 10MW / 10MWh and an initial SOC value of 0.5.

[0091] Table 1. Parameters of the transfer function model for photovoltaic power generation system

[0092] Table 2. Unit Model Parameters for Each Region

[0093] Table 3 Optimization Parameter Settings

[0094] Step 2. Propose a cross-regional collaborative optimization control strategy for energy storage in the interconnected power grid model. The flowchart of the cross-regional collaborative optimization control strategy for energy storage is as follows: Figure 3 As shown, the optimization calculation module is as follows: Figure 4 As shown, Pareto optimality is solved using the Gamultiobj algorithm in the Global Optimization Toolbox of MATLAB / Simulink. The Pareto front formed during the solution process is as follows: Figure 5 As shown.

[0095] Step 3. Set different initial energy storage value combinations for the three regions in the example to form different scenario operating conditions, and perform simulation verification of the proposed strategy. In the collaborative simulation of energy storage regulation, the energy storage SOC is set as shown in Table 4, denoted as Simulation A, and the simulation results are as follows. Figure 6 to Figure 9 As shown, the changes in SOC, energy storage output, and regional tie-line exchange power of the three regional energy storage systems before and after optimization are respectively represented.

[0096] Table 4 Initial values ​​of SOC in Simulation A

[0097] Step 4. Following simulation A in step 3, continue with the uncoordinated-coordinated energy storage simulation, denoted as simulation B. In this simulation, the energy storage SOC settings are shown in Table 5. The initial SOC values ​​of energy storage in all three regions are at the safe threshold. The simulation results are as follows: Figure 10 to Figure 13 As shown, the changes in SOC, energy storage output, and regional tie-line exchange power of the three regional energy storage systems before and after optimization are respectively represented.

[0098] Table 5 Initial values ​​of SOC in Simulation B

[0099] Step 5. In the actual operation of the system, load fluctuations and renewable energy output fluctuations are more variable over longer time periods, making the situation more complex for energy storage to participate in frequency regulation and coordinate. To better verify that the AGC optimization control strategy for cross-regional energy storage coordination of this invention can handle various energy storage operating states with different initial SOC values ​​in long-term scenarios, this embodiment simulates the 12-hour operating state of the interconnected regional power grid from 6:00 to 18:00 per day. The disturbances during operation include the range of... Continuous random load fluctuations, changes in photovoltaic output caused by variations in solar irradiance, and instantaneous step disturbances caused by large load shedding or grid connection, within a range not exceeding The energy storage SOC settings in the simulation are shown in Table 6, and the simulation results are as follows. Figure 14 to Figure 16 As shown, the table represents the changes in SOC, energy storage output, 0-1 decision variables indicating whether energy storage is coordinated, and the changes in power exchanged between inter-regional tie lines for energy storage in three regions of the interconnected power system operating for a relatively long period under optimization.

[0100] Table 6 Initial SOC values ​​during a longer simulation of 12 hours

[0101] Based on the simulation results above, it is easy to see that the AGC optimization control method for cross-regional energy storage considering conditional SOC balance proposed in this invention (1) can quickly act when the initial state of energy storage exceeds the safe range, enabling energy storage to achieve cross-regional collaborative control through tie lines, and exit operation after SOC recovers to the safe range; it can also promptly change the energy storage output when the energy storage reaches the triggering collaborative condition, achieving conditional SOC balance and ensuring the safety and reliability of energy storage output; (2) it can enable energy storage to transmit power through tie lines when the collaborative condition is triggered during a relatively long period of actual system operation, performing cross-regional collaborative optimization control to improve the stability of the system, and can meet the frequency regulation requirements of the local area when the cross-regional collaborative condition is not met. Therefore, the optimization control method of this invention provides a new optimization method for energy storage to participate in frequency regulation output across regions and share the frequency regulation task, and has good engineering application prospects.

[0102] In another embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used in the operation of an AGC optimization control method for cross-regional collaborative energy storage considering conditional SOC balancing.

[0103] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the AGC optimization control method for cross-regional energy storage considering conditional SOC balancing in the above embodiments.

[0104] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0105] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0106] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0107] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0108] This invention also provides a computer program product for executing any of the above-described AGC optimization control methods for cross-regional energy storage considering SOC balance. Since the computer program product provided by this invention belongs to the same inventive concept as the aforementioned AGC optimization control method for cross-regional energy storage considering SOC balance, it possesses all the advantages of the aforementioned AGC optimization control method for cross-regional energy storage considering SOC balance. Therefore, the beneficial effects of the computer program product provided by this invention will not be elaborated upon here.

[0109] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0110] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the scope of the technology disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention.

Claims

1. An AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance, characterized in that, include: Real-time assessment of the status of energy storage systems in each region, including the equivalent state of charge and the dynamic frequency regulation capability of the regional energy storage systems; Based on the equivalent state of charge and the dynamic frequency modulation capability, determine whether the preset necessary conditions for cross-regional cooperation are met. When the judgment result satisfies at least one of the necessary conditions for cross-regional coordination, a multi-objective optimization model is established with multiple objective functions as optimization objectives and grid operation parameters as constraints. The multi-objective optimization model is then solved to obtain the optimal output command of each regional energy storage system in the next AGC control cycle. The multiple objective functions include at least: a first objective function for balancing the equivalent state of charge of each regional energy storage system, a second objective function for minimizing the power transmission of inter-regional tie lines, and a third objective function for maximizing the remaining frequency regulation capacity of each regional energy storage system after meeting local frequency regulation requirements. The optimal output command is then sent to the corresponding regional energy storage system for execution.

2. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The assessment of the equivalent state of charge of the regional energy storage system is as follows: In the formula, for In the time-regional power grid The equivalent state of charge of an energy storage power station; For energy storage power stations Rated capacity; for Real-time energy storage power station The state of charge.

3. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The evaluation of the dynamic frequency regulation capability of the regional energy storage system is as follows: Define the continuous charge-discharge capability of energy storage for 1 minute, and use the continuous charge-discharge capability to measure the dynamic frequency regulation capability: ， In the formula, For the region Energy storage capacity for 1 minute of continuous charging and discharging; For energy storage capacity; This represents the maximum energy storage capacity. This represents the minimum energy storage capacity. This is the rated output power for energy storage; For the region The area control error signal; Considering the ramp rate and capacity constraints of the energy storage unit, the modified continuous charge-discharge capability, which characterizes the maximum support that the energy storage can provide in the next AGC control cycle, is defined as: ， In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; , They are respectively The actual upper and lower limits of the actual output of the energy storage system at all times; for Real-time active power of the energy storage system; The instruction cycle of the AGC system; , These are the rated up-rate and rated down-rate of the energy storage system, respectively.

4. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The necessary conditions for cross-regional collaboration include at least one of the following conditions: Condition 1: The equivalent state of charge of the regional energy storage system exceeds the preset safe operating range of the regional energy storage system, specifically: In the formula, for Time zone Equivalent state of charge of the medium-capacity energy storage system; The upper limit of the safe operating range preset for regional energy storage systems; The lower limit of the safe operating range preset for regional energy storage systems; Condition 2: The equivalent state of charge (SBC) of the regional energy storage system is within the preset warning range, and the current direction of the active power output of the regional energy storage system will cause the SBC of the regional energy storage system to change in a direction closer to the boundary of the safe operating range, specifically: In the formula, This is the preset upper limit of the warning range; This is the preset lower limit of the warning range; For the region Inside The output power of the battery energy storage system at all times; Condition 3: The dynamic frequency regulation capability of the regional energy storage system is less than the current local frequency regulation requirement of the regional energy storage system, specifically: In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system.

5. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The first objective function is constructed to minimize the variance of the equivalent state of charge of the energy storage system in each region during the next AGC control cycle, specifically: In the formula, This indicates the region of the next AGC control cycle after the energy storage system output changes. Equivalent state of charge of an energy storage system; express time The mean of the equivalent state of charge of the energy storage system in each region; To indicate the duration of the AGC control cycle; This indicates the output of the energy storage system in the next AGC control cycle; For the region Rated capacity of medium-sized energy storage.

6. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The second objective function is constructed to minimize the total power and power variation on the inter-regional interconnects in the next AGC control cycle, specifically: In the formula, , They represent Time zone Total power and total power change on the connection lines between other regions and Representing regions With the region Frequency deviation; This is the synchronous torque coefficient; The number of regions in the interconnected power grid; For the Laplace operator.

7. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 1, characterized in that, The third objective function is constructed to maximize the remaining real-time frequency regulation capability of each regional energy storage system after meeting local frequency regulation requirements in the next AGC control cycle, specifically: In the formula, for Time zone The continuous charging and discharging capability of the medium-sized energy storage system; For the region Inside The output power of the battery energy storage system at any time.

8. The AGC optimization control method for cross-regional energy storage collaboration considering conditional SOC balance as described in claim 4, characterized in that, The constraints include: upper and lower limits of energy storage system output, real-time frequency regulation capability of energy storage system, state of charge of energy storage system, tie line transmission power, system power balance, and necessary conditions for cross-regional collaboration. The necessary constraints for cross-regional collaboration include: The constraint corresponding to condition one is: In the formula, , The 0-1 auxiliary variables are introduced; These are relaxation parameters; The number of regions in the interconnected power grid; Indicates the region Whether energy storage participates in the collaboration, Indicates the region Energy storage participates in collaboration, Indicates the region Energy storage does not participate in the collaboration; The constraint corresponding to condition two is: In the formula, , , For the introduced 0-1 auxiliary variables, These are relaxation parameters; The constraint corresponding to condition three is: In the formula, This is an auxiliary variable consisting of 0 and 1.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements an AGC optimization control method for cross-regional collaborative energy storage that considers conditional SOC balance, as described in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the AGC optimization control method for cross-regional energy storage coordination that considers conditional SOC balance as described in any one of claims 1 to 8.

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