A method and related device for active balancing control of an energy storage power station

Abstract

The application discloses an energy storage power station active balancing control method and related device, relates to the power control technical field of energy storage power station, and the method comprises the following steps: collecting the operation state parameters of an energy storage converter and a power station total power scheduling instruction in real time; calculating the average SOC of the whole station based on the operation state parameters; calculating the target adjustment power to be distributed based on the power station total power scheduling instruction; constructing a dynamic weight and calculating a preliminary distribution power instruction; performing upper and lower limit amplitude verification and marking a lock state; calculating the power deviation of the sum of the preliminary distribution power instruction and the target adjustment power, and correcting each preliminary distribution power instruction in combination with the average SOC of the whole station; performing upper and lower limit amplitude verification on the corrected distribution power instruction, obtaining the verified power instruction, and delivering the verified power instruction to an adjustable energy storage converter. The application can realize the dual targets of high-precision tracking of the total power instruction and rapid balancing convergence of the average SOC of the whole station, and improve the available capacity, adjustment response speed and operation safety of the energy storage power station.

Description

Technical Field

[0001] This application relates to the field of power control technology for energy storage power stations, and in particular to an active balancing control method and related devices for energy storage power stations. Background Technology

[0002] With the rapid development of the new energy power generation industry, large-scale energy storage power stations are widely used in ancillary service scenarios such as grid peak shaving, frequency regulation, and voltage support. An energy storage power station consists of multiple energy storage units that need to complete charging and discharging regulation according to power commands issued by the grid. Each energy storage unit comprises an energy storage battery cluster and a PCS (energy storage converter). Each PCS corresponds to a set of energy storage batteries and independently receives power commands and operates. However, due to variations in battery cell manufacturing consistency, self-discharge differences, long-term charge-discharge cycle losses, and minor deviations in operating conditions, the SOC (State of Charge) of the energy storage battery clusters corresponding to each energy storage converter continues to show dispersion.

[0003] The existing equalization control technology has the following defects: (1) The traditional fixed ratio average allocation strategy does not combine the real-time SOC deviation to dynamically adjust the power allocation weight. The SOC convergence speed is slow, and long-term operation aggravates the unit charging and discharging imbalance. Some battery clusters reach the charging and discharging cutoff limit in advance, which greatly reduces the overall available capacity of the energy storage station and shortens the battery cycle life; (2) The power allocation does not take into account the upper and lower limit constraints of the power of each energy storage converter. When the dispatch command fluctuates frequently, it is easy for a single energy storage converter to exceed the limit and be locked. The power tracking deviation of the whole station is large, the adjustment oscillates, and the response is lagging. It is impossible to simultaneously meet the dual goals of accurate total power tracking and SOC balance; (3) There is a lack of power deviation dead zone judgment and hierarchical iterative correction mechanism. The continuous and repeated adjustment of small power deviation increases equipment loss. There is no closed-loop iterative compensation under large deviation conditions. The steady-state adjustment error is high and it is difficult to meet the high-precision control requirements of the power grid AGC (Automatic Generation Control).

[0004] Therefore, how to achieve the dual goals of high-precision tracking of total power commands and rapid equalization and convergence of the entire station's SOC, thereby improving the available capacity, adjustment response speed, and operational safety of energy storage power stations, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The purpose of this application is to provide an active balancing control method and related devices for energy storage power stations, which can achieve the dual goals of high-precision tracking of total power commands and rapid balancing convergence of the entire station's SOC, thereby improving the available capacity, regulation response speed, and operational safety of energy storage power stations.

[0006] To achieve the above objectives, this application provides the following solution: Firstly, this application provides an active balancing control method for an energy storage power station, comprising the following steps: Real-time acquisition of operating status parameters of all energy storage converters in the energy storage power station and total power dispatch instructions of the power station; the operating status parameters include: operating flag, charge / discharge enable flag, real-time active power, current SOC, upper limit of single-unit power and lower limit of single-unit power.

[0007] Based on the aforementioned operating status parameters, non-adjustable energy storage converters and adjustable energy storage converters are distinguished, and the average SOC of the entire station is calculated.

[0008] Based on the total power dispatching command of the power plant, the target regulating power to be allocated is calculated by deducting the total power of the non-adjustable energy storage converter and the sum of the power of the locked energy storage converter.

[0009] Based on the charging and discharging direction of the target power to be allocated, dynamic weights are constructed based on the SOC deviation of the corresponding energy storage unit of each energy storage converter, and the initial power allocation command of each energy storage converter is calculated.

[0010] The upper and lower limits of each of the initial power allocation commands are checked, and the energy storage converters that exceed their own power limits are marked as locked, while the energy storage converters that do not exceed their own power limits are marked as adjustable energy storage converters.

[0011] Calculate the power deviation between the sum of the initial power allocation commands of all the adjustable energy storage converters and the target regulating power, and based on the power deviation and the preset dead zone threshold, combined with the station average SOC, correct each of the initial power allocation commands to obtain each corrected power allocation command.

[0012] Each of the modified power allocation commands is subjected to upper and lower limit verification to obtain each verified power command and then sent to the corresponding adjustable energy storage converter.

[0013] In a second aspect, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the active balancing control method for energy storage power stations described in the first aspect.

[0014] Thirdly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the active balancing control method for energy storage power stations described in the first aspect.

[0015] Fourthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the active balancing control method for energy storage power stations described in the first aspect.

[0016] According to the specific embodiments provided in this application, this application has the following technical effects: This application provides an active balancing control method and related devices for an energy storage power station. First, this application distinguishes between charging and discharging operating conditions, constructing allocation weights based on the deviation of the energy storage unit's State of Charge (SOC) from the upper and lower limits. Units with higher SOC dispersion bear more regulation power, which can quickly reduce the SOC difference among all energy storage units in the station, preventing some energy storage units from prematurely reaching their charge / discharge limits and causing overcharging or over-discharging problems. It fully releases the effective capacity of the entire station's batteries, reduces cycle losses caused by uneven battery charging and discharging, effectively increases the usable capacity of the energy storage power station, extends the service life of the entire energy storage system, and adapts to the long-term AGC frequency regulation operation requirements of the power grid. Second, this application pre-screens non-adjustable energy storage converters, directly eliminating their fixed output when calculating the target regulation power; simultaneously, it performs individual power upper and lower limit checks on the initial allocated power, marking and locking energy storage converters that exceed the limits and separately calculating their total power, automatically isolating and locking devices during iterative allocation. The over-limit power and fault blocking of a single energy storage converter will not interfere with the power allocation logic of the entire station, realizing multi-level hardware power constraint protection, reducing the risk of overload and overcurrent operation, and significantly improving the operational stability of large-scale energy storage stations with multiple energy storage converters in parallel. Furthermore, this application corrects the initial power allocation command by setting a power deviation dead zone threshold, which can avoid the loss of power electronic devices caused by frequent switching of charging and discharging conditions of the energy storage converter, eliminate the power tracking deviation of the entire station, and accurately follow the power dispatch command issued by the grid. The adjustment response is fast, and the steady-state power deviation is small, fully meeting the high-precision frequency regulation assessment indicators of the new power system AGC. Moreover, this application sets two levels of power upper and lower limit verification. After the initial allocation is completed, the first round of limit locking is performed, and before the correction is completed and issued, the upper and lower limit verification is performed again. This dual constraint ensures that the power command issued to the energy storage converter is always within the individual allowable power range, eliminating the problem of power command over-limit at the algorithm level, avoiding frequent operation of equipment hardware protection, and improving the control reliability of the energy storage power station. Compared to traditional energy storage equalization control schemes that use a fixed ratio to distribute power equally without taking into account SOC differences, this application uses a complete closed-loop control logic with dynamic SOC weight allocation, power level limiting and locking, and dead zone hierarchical progressive correction. This enables the dual goals of high-precision tracking of total power commands and rapid equalization and convergence of the entire station's SOC, thereby improving the available capacity, adjustment response speed, and operational safety of the energy storage power station. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 An application environment diagram of an active balancing control method for an energy storage power station provided in an embodiment of this application; Figure 2 A flowchart illustrating an active balancing control method for an energy storage power station, provided as an embodiment of this application; Figure 3 A schematic diagram of the SOC equalization allocation strategy for 1-50 energy storage converters and SOC for an embodiment of this application; Figure 4 A schematic diagram of the SOC equalization allocation strategy for 51-100 energy storage converters and SOC for an embodiment of this application; Figure 5 A schematic diagram of the SOC equalization allocation strategy for 101-150 energy storage converters and SOC, provided in an embodiment of this application; Figure 6 A schematic diagram of the SOC equalization allocation strategy for 151-200 energy storage converters and SOC, provided in an embodiment of this application; Figure 7 A schematic diagram of the SOC equalization allocation strategy for 201-250 energy storage converters and SOC, provided in an embodiment of this application; Figure 8 A schematic diagram of the SOC equalization allocation strategy for 251-300 energy storage converters and SOC, provided in an embodiment of this application; Figure 9 This is a schematic diagram of the overall response curve of the SOC balanced allocation strategy provided in an embodiment of this application; Figure 10 This is a schematic diagram of the structure of an active balancing control system for an energy storage power station, provided in one embodiment of this application. Figure 11 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This application provides an active balancing control method and related apparatus for energy storage power stations. It is applicable to the AGC frequency regulation, power point tracking, and SOC active balancing coordinated control scenarios of multi-energy storage converter parallel energy storage power stations under new power systems. It can achieve the dual objectives of high-precision tracking of total power commands and rapid SOC balancing convergence of the entire station, thereby improving the available capacity, regulation response speed, and operational safety of energy storage power stations. It solves the problems of slow SOC convergence, low power point tracking accuracy, easy regulation oscillation, and lack of integrated equipment power constraints in existing energy storage power station balancing strategies.

[0021] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] The active balancing control method for energy storage power stations provided in this application embodiment can be applied to, for example... Figure 1In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be set up independently, integrated into server 104, or placed in the cloud or on another server. Terminal 102 can send the operating status parameters of all energy storage converters in the energy storage power station and the power station's total power dispatch command to server 104. After receiving the operating status parameters of all energy storage converters in the energy storage power station and the power station's total power dispatch command, server 104 distinguishes between non-adjustable and adjustable energy storage converters based on the operating status parameters and calculates the average SOC of the entire station. Based on the power station's total power dispatch command, it deducts the total power of non-adjustable energy storage converters and the sum of the power of locked-in energy storage converters to calculate the target adjustment power to be allocated. According to the charging and discharging direction of the target adjustment power to be allocated, dynamic weights are constructed based on the SOC deviation of the corresponding energy storage units of each energy storage converter, and the preliminary allocation power command for each energy storage converter is calculated. Each preliminary power allocation command undergoes upper and lower limit verification. Energy storage converters exceeding their own power limits are marked as locked, while those not exceeding their power limits are marked as adjustable. The power deviation between the sum of the preliminary power allocation commands for all adjustable energy storage converters and the target adjustment power is calculated. Based on the power deviation, a preset dead zone threshold, and the station-wide average SOC, each preliminary power allocation command is corrected to obtain corrected power allocation commands. Each corrected power allocation command undergoes upper and lower limit verification to obtain verified power commands, which are then sent to the corresponding adjustable energy storage converter. Server 104 can feed back the obtained verified power commands to terminal 102. In addition, in some embodiments, the active balancing control method for the energy storage power station can also be implemented by the server 104 or the terminal 102 separately. For example, the terminal 102 can directly perform active balancing control processing on the operating status parameters of all energy storage converters in the energy storage power station and the total power dispatching instructions of the power station. Alternatively, the server 104 can obtain the operating status parameters of all energy storage converters in the energy storage power station and the total power dispatching instructions of the power station from the data storage system, and perform active balancing control processing on the operating status parameters of all energy storage converters in the energy storage power station and the total power dispatching instructions of the power station.

[0023] The terminal 102 can be, but is not limited to, various desktop computers, laptops, smartphones, tablets, and IoT devices. The server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers, or it can be a cloud server.

[0024] In one exemplary embodiment, such as Figure 2As shown, an active balancing control method for an energy storage power station is provided. This method is executed by computer equipment, specifically by a terminal or server alone, or by both a terminal and a server. In this embodiment, the method is applied to... Figure 1 Taking server 104 as an example, the following steps are included: S1: Real-time acquisition of operating status parameters of all energy storage converters in the energy storage power station and total power dispatch instructions of the power station.

[0025] S2: Based on the operating status parameters, distinguish between non-adjustable energy storage converters and adjustable energy storage converters, and calculate the average SOC of the entire station.

[0026] S3: Based on the total power dispatching command of the power station, deduct the total power of the non-adjustable energy storage converter and the sum of the power of the locked energy storage converter, and calculate the target adjustment power to be allocated.

[0027] S4: Based on the charging and discharging direction of the target power to be allocated, construct dynamic weights based on the SOC deviation of the corresponding energy storage unit of each energy storage converter, and calculate the preliminary power allocation command for each energy storage converter.

[0028] S5: Perform upper and lower limit verification on each of the preliminary power allocation commands, mark the energy storage converter that exceeds its own power limit as locked, and accumulate the total power of all locked energy storage converters. At the same time, mark the energy storage converter that does not exceed its own power limit as an adjustable energy storage converter.

[0029] S6: Calculate the power deviation between the sum of the initial power allocation commands of all the adjustable energy storage converters and the target adjustment power, and based on the power deviation and the preset dead zone threshold, combined with the average SOC of the entire station, correct each of the initial power allocation commands to obtain each corrected power allocation command.

[0030] S7: Perform upper and lower limit verification on each of the modified power allocation commands to ensure that the power does not exceed the extreme value of the individual unit. After the upper and lower limit verification is completed, the verified power commands are the final execution commands and are sent to the corresponding adjustable energy storage converters to perform charge and discharge regulation, thereby realizing active balancing control of the energy storage power station.

[0031] Implementing steps S1 to S7 above can achieve the dual goals of high-precision tracking of total power commands and rapid equalization and convergence of the entire station's SOC, thereby improving the available capacity, adjustment response speed, and operational safety of the energy storage power station.

[0032] As an optional implementation, in step S1, the operating status parameters include: operating flag, charge / discharge enable flag, real-time active power, current SOC, upper limit of individual unit power, and lower limit of individual unit power. The total power dispatch instruction for the power station is a station-wide active power adjustment instruction issued by the grid AGC.

[0033] As an optional implementation, after step S1, the active balancing control method for the energy storage power station further includes: initializing the intermediate variables of the total power of the non-adjustable energy storage converter and the total power of the locked-state energy storage converter.

[0034] As an optional implementation, in step S2, the non-adjustable energy storage converter includes energy storage converters that are fault-stopped, locked out, have their operation flags invalidated, or have their charge / discharge enable flags turned off. The calculated average SOC for the entire station is used for subsequent deviation compensation strategies, serving as a benchmark parameter for selecting energy storage converters to be compensated. When deviation compensation is performed when the power deviation exceeds the dead zone threshold, the adjustable energy storage converter with the corresponding energy storage unit SOC closest to the average SOC for the entire station is selected to bear the entire power deviation, ensuring that the equalization adjustment does not exacerbate the SOC dispersion.

[0035] As an optional implementation, in step S4, dynamic weights are constructed based on the SOC deviation of the corresponding energy storage units of each energy storage converter, according to the charging and discharging direction of the target regulating power to be allocated. This specifically includes the following steps: S41: When the target adjustment power to be allocated is greater than 0, the energy storage power station performs a discharge operation. The SOC deviation corresponding to a single energy storage converter is the absolute value of the difference between the current SOC of the energy storage unit and the preset lower limit of SOC.

[0036] S42: When the target adjustment power to be allocated is less than 0, the energy storage power station performs charging operation. The SOC deviation corresponding to a single energy storage converter is the absolute value of the difference between the current SOC of the energy storage unit and the preset SOC upper limit.

[0037] As an optional implementation, step S4 involves calculating the preliminary power allocation command for each energy storage converter, specifically including the following steps: S43: Calculate the sum of the SOC deviations for all the adjustable energy storage converters.

[0038] S44: When the sum of the SOC deviations is approximately 0 (i.e., about equal to 0), the target regulating power to be allocated is evenly distributed to each of the adjustable energy storage converters.

[0039] S45: When the total SOC deviation is not 0, the ratio of the SOC deviation of a single energy storage converter to the total SOC deviation is used as a dynamic weight, and the dynamic weight is multiplied by the target regulation power to be allocated to obtain the preliminary allocation power command of the energy storage converter.

[0040] As an optional implementation, in step S5, upper and lower limit checks are performed on each preliminary power allocation command: if the preliminary power allocation command corresponding to a single energy storage converter exceeds the upper or lower limit of the single power of the energy storage converter itself, the energy storage converter is marked as locked, and the energy storage converter in the locked state is a non-adjustable energy storage converter; otherwise, the energy storage converter is marked as unlocked, and the energy storage converter in the unlocked state is an adjustable energy storage converter.

[0041] As an optional implementation, in step S5, the total power of all locked energy storage converters is accumulated and recorded. This is used to deduct the fixed output of the locked unit when calculating the target regulation power to be allocated each time, ensuring that only the adjustable energy storage converters in the unlocked state bear the remaining regulation demand. At the same time, during the iterative redistribution process, the target regulation power is updated in real time based on this total locked power, realizing automatic isolation of over-limit energy storage converters, preventing the power allocation from continuously exceeding the limit, and improving the power tracking accuracy and operational safety of the entire station.

[0042] As an optional implementation, in step S6, the power deviation between the sum of the initial power allocation commands of all the adjustable energy storage converters and the target regulation power is calculated. Based on the power deviation and the preset dead zone threshold, combined with the average SOC of the entire station, each of the initial power allocation commands is corrected to obtain each corrected power allocation command. Specifically, this includes the following steps: S61: Calculate the sum of the preliminary power allocation commands for all the adjustable energy storage converters based on the marked adjustable energy storage converters and the corresponding preliminary power allocation commands.

[0043] S62: Calculate the power deviation between the sum of the initial allocated power commands of all the adjustable energy storage converters and the target regulated power.

[0044] S63: Based on the relationship between the absolute value of the power deviation and the preset dead zone threshold, and in conjunction with the average SOC of the entire station, determine the corresponding correction strategy. The correction strategy includes: a deviation compensation strategy and an iterative redistribution strategy.

[0045] When the absolute value of the power deviation is less than the preset dead zone threshold, a deviation compensation strategy is executed. This strategy involves selecting the energy storage converter whose SOC is closest to the average SOC of the entire station and is not locked, and adding all power deviations to the power command of that energy storage converter. When the absolute value of the power deviation is greater than or equal to the preset dead zone threshold, an iterative redistribution strategy is executed. This strategy involves removing all locked energy storage converters and repeatedly executing the target regulation power calculation, SOC dynamic weight allocation, and preliminary allocation power command upper and lower limit verification process (i.e., repeatedly executing the above steps S3 to S5) until the absolute value of the power deviation is less than the preset dead zone threshold or the maximum number of iterations is reached.

[0046] S64: Based on the correction strategy, determine the corrected power allocation command for each of the adjustable energy storage converters.

[0047] As an optional implementation, in step S63, the preset dead zone threshold and the maximum number of iterations are both configurable fixed parameters; when the number of iterations reaches the maximum number of iterations but the power deviation still exceeds the preset dead zone threshold range, the current corrected power allocation command is directly output and a power tracking anomaly alarm is reported.

[0048] As an optional implementation, in step S63, during the execution of the iterative redistribution strategy, the total power of all currently locked energy storage converters is re-accumulated in each round of the loop, and the target regulation power to be allocated is updated.

[0049] In an exemplary embodiment, to illustrate the technical solution provided in this application, an active balancing control method for an energy storage power station is provided. This method aims to solve the problems of reduced available capacity and poor regulation performance caused by inconsistent State of Charge (SOC) of energy storage units in the prior art, achieving the dual goals of accurate tracking of total power commands and rapid SOC balancing of each unit. By real-time statistical analysis of the charging and discharging capabilities and SOC status of each energy storage converter, a dynamic weight allocation model based on SOC deviation is constructed. Under discharge conditions, energy storage converters with high SOC are prioritized for scheduling; under charging conditions, energy storage converters with low SOC are prioritized for scheduling, effectively accelerating the convergence of SOC consistency. Simultaneously, a multi-level power constraint processing mechanism and an iterative correction algorithm based on dead zones are introduced, ensuring accurate tracking of total power commands while avoiding control failures caused by single device exceeding limits, significantly improving the regulation accuracy, response speed, and operational safety of the energy storage power station. The specific implementation process of this method includes the following steps: Step 1: Data Acquisition and Initialization.

[0050] Step 1.1: Real-time acquisition of operating status parameters of N energy storage converters within the energy storage power station.

[0051] In this embodiment of the application, the set U={1,2,...,N} is defined as the index of all energy storage converters. For any nth Taiwan energy storage converter, obtain its operating flag bit Charge / discharge enable flag (Permitted discharge) and (Charging allowed), Current active power Current SOC value Maximum power limit and minimum active power limit Among them, minimum active power limit Typically, the value is negative. Simultaneously, the total power dispatch command for the power plant is obtained. .

[0052] Step 1.2: Initialize intermediate variables, including the maximum active power that the entire station can generate. The minimum active power that the entire station can send Total non-adjustable power wait.

[0053] Step 2: Statistics on the overall station operation status and calculation of the maximum and minimum active power generation of the entire station.

[0054] Step 2.1: Traverse all energy storage converters, count the power regulation capacity of the devices that are in operation and not locked, and calculate the maximum active power that the entire station can generate. and the minimum active power of the entire site The calculation formula is: .

[0055] .

[0056] Step 2.2: Calculate the total SOC value and number of operating energy storage converters. Calculate the average SOC value for the entire station. The calculation formula is: .

[0057] Step 3: Calculation of the target adjustment power to be allocated.

[0058] Step 3.1: According to the power plant's total power dispatch instruction Subtract the current power of non-adjustable energy storage converters (such as those that are faulty, shut down, or have reached their limits). The total power of the energy storage converter that has been locked due to reaching its limit (marked as locked state) Calculate the target adjustment power to be allocated The calculation formula is: .

[0059] in, Indicates the target adjustment power to be allocated; This represents the total power of the energy storage converter that is locked due to reaching its limit (marked as locked state); This refers to the fixed output power that needs to be additionally added to the adjustable range (usually a fixed load / fixed generation unit power that must be constant and cannot be adjusted). This power belongs to the station's own constant fixed load / fixed generation. This part of the power will not participate in dynamic regulation, which is equivalent to offsetting part of the total command demand. Therefore, it needs to be added when solving for the power allocated to the adjustable energy storage converter. .

[0060] Step 3.2: Calculate the target adjustment power based on Step 3.1. Combined with the maximum active power generated by the entire station calculated in step 2.1 and the minimum active power of the entire site Confirm the final target adjustment power The calculation formula is: .

[0061] Step 4: Dynamic weight allocation based on SOC bias.

[0062] Step 4.1: Adjust power according to the target to be allocated The direction (charging or discharging) is used to construct dynamic weighting factors.

[0063] In this embodiment of the application, a SOC deviation metric is defined. .

[0064] when When the discharge tendency is >0, then the following formula applies: .

[0065] when When <0 (charging trend), the following formula applies: .

[0066] in, and These are the set lower and upper limits of SOC, respectively.

[0067] Step 4.2: Calculate the sum of the SOC deviations of all adjustable energy storage converters. The calculation formula is: .

[0068] like If the power is maintained or evenly distributed according to the current power level, then the initial allocation is calculated. Power command of Taiwan energy storage converter The calculation formula is: .

[0069] This formula embodies the active balancing concept that "the greater the deviation, the more power is shared."

[0070] Step 5: Constraint and limit amplitude and extreme value protection.

[0071] Step 5.1: For the initial allocation of the first... Power command of Taiwan energy storage converter Perform a physical constraint check. If the power command calculated by a certain energy storage converter exceeds its... or Then fix it to the limit value ( or And mark the energy storage converter as "locked out" ( ( ), and will no longer participate in subsequent fine-tuning allocations.

[0072] Step 5.2: Record the total power of the energy storage converters that are marked as locked. .

[0073] Step 6: Dead zone detection and iterative correction.

[0074] Step 6.1: Calculate the sum of the initial allocated power commands for all adjustable energy storage converters. The calculation formula is: .

[0075] Step 6.2: Calculate the sum of the initial allocated power commands for all adjustable energy storage converters. With the target adjustment power to be allocated deviation The calculation formula is: .

[0076] Step 6.3: Set the preset dead zone threshold .like Execute the deviation compensation strategy if If so, then the iterative reallocation strategy will be executed.

[0077] In this embodiment of the application, the deviation compensation strategy is as follows: find the current SOC that is closest to the overall station average. And unlocked energy storage converter The deviations are directly superimposed (the power command for each of the initially allocated energy storage converters can be obtained through step 4, and the selected first converter can be obtained through steps 5 and 6). The power command for the energy storage converter is sent to the energy storage converter for execution, while the power commands for the other energy storage converters remain unchanged. This results in the superimposed deviation. The next Power command of Taiwan energy storage converter It can be expressed as the following formula: .

[0078] In this embodiment, the iterative redistribution strategy is as follows: Return to step 4, repeatedly execute steps 4-5, exclude energy storage converters that are already locked, recalculate the weights of the remaining adjustable energy storage converters, until... Or reach the maximum number of iterations .

[0079] Step 7: Power command issued.

[0080] Step 7.1: Obtain the final calculated result Perform a final upper and lower limit check (hard limit check) to ensure the following formula holds true: .

[0081] The power command is sent to each energy storage converter for execution, as shown in the following formula: .

[0082] in, For the first The power command executed by the energy storage converter.

[0083] This application embodiment establishes an energy storage power station containing 300 2.5×2MW·h energy storage units for simulation verification. A SOC (State of Charge) equalization allocation strategy is adopted, and the rated power of the energy storage power station is... =750MW, tested according to the design power command, as shown in Table 1 and Figures 3 to 9 The test results are shown.

[0084] Table 1. SOC Balancing Strategy Full-Site Response Test Record Table

[0085] in, It is the sum of the maximum active power that the entire station can generate.

[0086] At the start of the test (30 seconds), the power command and SOC of each energy storage unit under SOC equalization were as follows: Figures 3 to 8 As shown, where, Figure 3A schematic diagram of power commands and SOC for 1-50 energy storage converters for SOC equalization allocation strategy. Figure 4 A schematic diagram of power commands and SOC for 51-100 energy storage converters for SOC equalization allocation strategy. Figure 5 A schematic diagram of power commands and SOC for 101-150 energy storage converters for SOC equalization allocation strategy. Figure 6 A schematic diagram of power commands and SOC for 151-200 energy storage converters for SOC equalization allocation strategy. Figure 7 A schematic diagram of power commands and SOC for 201-250 energy storage converters for SOC equalization allocation strategy. Figure 8 Power commands and SOC diagrams for 251-300 energy storage converters for SOC balanced distribution strategy. Figure 9 The diagram shows the overall response curve of the SOC equalization allocation strategy, demonstrating that the energy storage station responded well to the issued active power command. The test results indicate that, under proportional allocation mode, the logic of the energy storage station participating in the AGC function is correct, with an adjustment time between 1 and 2 seconds and a steady-state deviation between 0 and 0.20%.

[0087] Based on the same inventive concept, this application also provides an active balancing control system for an energy storage power station to implement the active balancing control method for the energy storage power station described above. The solution provided by this system is similar to the solution described in the above method; therefore, the specific limitations in the embodiments of the active balancing control system for the energy storage power station provided below can be found in the limitations of the active balancing control method for the energy storage power station described above, and will not be repeated here.

[0088] In one exemplary embodiment, such as Figure 10 As shown, an active balancing control system for an energy storage power station is provided, comprising the following modules: The data acquisition module is used to collect the operating status parameters of all energy storage converters in the energy storage power station and the total power dispatch instructions of the power station in real time.

[0089] The statistical analysis module is used to distinguish between non-adjustable and adjustable energy storage converters based on operating status parameters, and to calculate the average SOC of the entire station.

[0090] The power allocation module is used to calculate the target regulating power to be allocated based on the total power dispatch command of the power plant, after deducting the total power of the non-adjustable energy storage converter and the sum of the power of the locked energy storage converter.

[0091] The weight allocation module is used to build a dynamic weight allocation model and calculate the initial power allocation command for each energy storage converter.

[0092] The iterative correction module is used to perform upper and lower limit verification on each preliminary power allocation command, mark the energy storage converter that exceeds its own power limit as locked, and mark the energy storage converter that does not exceed its own power limit as adjustable energy storage converter; and calculate the power deviation between the sum of the preliminary power allocation commands of all adjustable energy storage converters and the target adjustment power, and correct each preliminary power allocation command according to the power deviation and the preset dead zone threshold to obtain each corrected power allocation command.

[0093] The power command output module is used to perform upper and lower limit verification on each corrected power allocation command, obtain each verified power command, and send it to the corresponding adjustable energy storage converter.

[0094] Compared to traditional energy storage balancing control schemes that use a fixed ratio to distribute power equally without considering SOC differences, the embodiments of this application have the following technical advantages through a complete closed-loop control logic that uses dynamic SOC weight allocation, power level limiting and locking, and dead zone hierarchical progressive correction: (1) Differentiated dynamic weight allocation accelerates the convergence of SOC balance across the entire station and improves the utilization rate of energy storage capacity and battery life: The embodiments of this application distinguish between charging and discharging conditions, and construct the allocation weight based on the deviation of the SOC of the energy storage unit from the upper and lower limits. The energy storage unit with a higher degree of SOC dispersion undertakes more regulation power, which can quickly reduce the SOC difference of each energy storage unit in the entire station, and avoid some energy storage units from reaching the charging and discharging limits in advance and causing overcharging and over-discharging problems; fully release the effective capacity of the entire station's batteries, reduce the cycle loss caused by the unbalanced charging and discharging of batteries, effectively improve the available capacity of the energy storage station, extend the service life of the entire energy storage system, and adapt to the long-term AGC frequency regulation operation requirements of the power grid.

[0095] (2) The system classifies adjustable, non-adjustable, and locked energy storage converters, resulting in strong equipment fault tolerance and higher operational safety. In this embodiment, non-adjustable energy storage converters that have experienced fault shutdowns, lockout protection, or enable failures are pre-screened, and their fixed output is directly excluded when calculating the target adjustable power. Simultaneously, individual power upper and lower limit checks are performed on the initial power allocation, marking and locking out energy storage converters exceeding their limits and separately calculating their total power. During iterative allocation, the locked devices are automatically isolated. Power overruns and fault lockouts of a single energy storage converter will not interfere with the overall power allocation logic of the entire station, achieving multi-level hardware power constraint protection, reducing the risk of overload and overcurrent operation, and significantly improving the operational stability of large-scale energy storage stations with multiple energy storage converters in parallel.

[0096] (3) A hierarchical correction strategy of compensation followed by iteration is adopted, resulting in high power tracking accuracy and reducing losses from frequent equipment adjustments. In this embodiment, a power deviation dead zone threshold is set, so small deviations do not require repeated adjustments, avoiding power electronic device losses caused by frequent switching of charging and discharging conditions of the energy storage converter; when the deviation exceeds the threshold, single-point deviation compensation is used first to quickly eliminate the deviation, and iterative redistribution is only initiated when compensation is ineffective, taking into account both adjustment speed and computational efficiency. The entire correction mechanism eliminates the power tracking deviation of the entire station in a closed loop, and can accurately follow the power dispatching instructions issued by the power grid. The adjustment response is fast and the steady-state power deviation is small, which fully meets the high-precision frequency regulation assessment indicators of the new power system AGC.

[0097] (4) Iterative redistribution dynamically updates the locked power, adapting to large-scale energy storage clusters. The algorithm is lightweight and has low computational overhead. In the iterative redistribution process of this application, the locked power of the energy storage converter is recalculated and the target adjustment power is updated in each round of the cycle. Failed adjustment units are dynamically eliminated, which has a strong adaptability to operating conditions. The algorithm only performs weight calculations on adjustable units, avoiding repeated calculations of invalid devices, reducing the real-time computing pressure on the energy management controller, and can stably support centralized energy storage and containerized distributed energy storage scenarios with hundreds of energy storage converters connected in parallel. It has strong versatility.

[0098] (5) Dual power limiting verification as a fallback to prevent power command overruns and ensure high control reliability. The embodiment of this application sets up two levels of power limiting verification: after the initial allocation is completed, the first round of limiting locking is performed, and before the correction is completed and the power is issued, a hard limiting verification is performed again. The dual constraints ensure that the power command issued to the energy storage converter is always within the allowable power range of the individual unit. This eliminates the problem of power command overruns from the algorithm level, avoids frequent operation of equipment hardware protection, and improves the control reliability of the energy storage power station.

[0099] (6) The parameters can be flexibly configured to facilitate on-site operation and maintenance to adapt to different station operating conditions. The preset dead zone threshold and the maximum number of iterations in the embodiments of this application can be customized according to the capacity of the energy storage power station and the grid dispatch assessment standards; when the power deviation cannot be eliminated after the maximum number of iterations, the current instruction can be output and an abnormal alarm can be reported, which facilitates the operation and maintenance personnel to quickly locate equipment faults and power matching abnormalities, reduce the difficulty of station operation and maintenance, and improve the intelligent operation and maintenance level of the energy storage power station.

[0100] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 11As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs in the non-volatile storage media to run. The database stores the operating status parameters of all energy storage converters within the energy storage power station and the power station's total power dispatch instructions. The I / O interfaces are used for information exchange between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements an active balancing control method for the energy storage power station.

[0101] Figure 11 The structures shown are merely block diagrams of some structures related to the present application and do not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than shown in the figures, or combine certain components, or have different component arrangements. In an exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0102] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0103] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0104] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of related data must comply with relevant regulations and be authorized by the owner of the corresponding device.

[0105] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0106] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0107] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An active balancing control method for an energy storage power station, characterized in that, include: Real-time acquisition of operating status parameters of all energy storage converters in the energy storage power station and total power dispatch instructions of the power station; The operating status parameters include: operating flag, charge / discharge enable flag, real-time active power, current SOC, upper limit of single-unit power, and lower limit of single-unit power; Based on the aforementioned operating status parameters, non-adjustable energy storage converters and adjustable energy storage converters are distinguished, and the average SOC of the entire station is calculated. Based on the power plant's total power dispatching instruction, the target regulating power to be allocated is calculated by deducting the total power of the non-adjustable energy storage converter and the sum of the power of the locked energy storage converter. Based on the charging and discharging direction of the target power to be allocated, dynamic weights are constructed based on the SOC deviation of the corresponding energy storage unit of each energy storage converter, and the initial power allocation command of each energy storage converter is calculated. The upper and lower limit verifications are performed on each of the preliminary power allocation commands, and the energy storage converters that exceed their own power limits are marked as locked, while the energy storage converters that do not exceed their own power limits are marked as adjustable energy storage converters. Calculate the power deviation between the sum of the initial power allocation commands of all the adjustable energy storage converters and the target regulation power, and based on the power deviation and the preset dead zone threshold, combined with the station average SOC, correct each of the initial power allocation commands to obtain each corrected power allocation command; Each of the modified power allocation commands is subjected to upper and lower limit verification to obtain each verified power command and then sent to the corresponding adjustable energy storage converter.

2. The active balancing control method for energy storage power stations according to claim 1, characterized in that, Based on the charging and discharging direction of the target regulating power to be allocated, a dynamic weight is constructed based on the SOC deviation of the corresponding energy storage unit of each energy storage converter, specifically including: When the target adjustment power to be allocated is greater than 0, the energy storage power station performs a discharge operation. The SOC deviation corresponding to a single energy storage converter is the absolute value of the difference between the current SOC of the energy storage unit and the preset lower limit of SOC. When the target adjustment power to be allocated is less than 0, the energy storage power station performs charging operation. The SOC deviation corresponding to a single energy storage converter is the absolute value of the difference between the current SOC of the energy storage unit and the preset SOC upper limit.

3. The active balancing control method for energy storage power stations according to claim 2, characterized in that, Calculate the initial power allocation command for each energy storage converter, specifically including: Calculate the sum of the SOC deviations for all the aforementioned adjustable energy storage converters; When the sum of the SOC deviations is approximately 0, the target regulating power to be allocated is evenly distributed to each of the adjustable energy storage converters. When the sum of the SOC deviations is not zero, the ratio of the SOC deviation of a single energy storage converter to the sum of the SOC deviations is used as a dynamic weight, and the dynamic weight is multiplied by the target regulating power to be allocated to obtain the preliminary allocation power command for the energy storage converter.

4. The active balancing control method for energy storage power stations according to claim 1, characterized in that, Calculate the power deviation between the sum of the initial power allocation commands for all adjustable energy storage converters and the target regulating power. Based on the power deviation and a preset dead zone threshold, combined with the station-wide average SOC, correct each initial power allocation command to obtain corrected power allocation commands, specifically including: Based on each of the marked adjustable energy storage converters and the corresponding preliminary power allocation commands, calculate the sum of the preliminary power allocation commands for all the adjustable energy storage converters; Calculate the power deviation between the sum of the initial allocated power commands for all the adjustable energy storage converters and the target regulated power; Based on the relationship between the absolute value of the power deviation and the preset dead zone threshold, and in conjunction with the average SOC of the entire station, a corresponding correction strategy is determined. The correction strategy includes a deviation compensation strategy and an iterative redistribution strategy. If the absolute value of the power deviation is less than the preset dead zone threshold, the deviation compensation strategy is executed. The deviation compensation strategy is as follows: select the energy storage converter whose SOC is closest to the average SOC of the entire station and is not locked, and add all power deviations to the power command of that energy storage converter. If the absolute value of the power deviation is greater than or equal to the preset dead zone threshold, the iterative redistribution strategy is executed. The iterative redistribution strategy is as follows: remove all locked energy storage converters, and repeatedly execute the target regulation power calculation, SOC dynamic weight allocation, and preliminary allocation power command upper and lower limit verification process until the absolute value of the power deviation is less than the preset dead zone threshold or the maximum number of iterations is reached. Based on the correction strategy, the corrected power allocation command for each of the adjustable energy storage converters is determined.

5. The active balancing control method for energy storage power stations according to claim 4, characterized in that, The preset dead zone threshold and the maximum number of iterations are both configurable fixed parameters. When the number of iterations reaches the maximum number of iterations but the power deviation still exceeds the preset dead zone threshold range, the current corrected power allocation command is directly output and a power tracking anomaly alarm is reported.

6. The active balancing control method for an energy storage power station according to claim 4 or 5, characterized in that, During the execution of the iterative redistribution strategy, the total power of all locked energy storage converters is re-accumulated in each loop, and the target regulation power to be allocated is updated.

7. The active balancing control method for energy storage power stations according to claim 1, characterized in that, The non-adjustable energy storage converter includes: energy storage converters with fault shutdown, lockout protection, operation flag failure, or charge / discharge enable flag closed.

8. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that the processor executes the computer program to implement the active balancing control method for an energy storage power station as described in any one of claims 1-7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the active balancing control method for energy storage power stations as described in any one of claims 1-7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the active balancing control method for energy storage power stations as described in any one of claims 1-7.

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