A power control method, system and device for electrical energy storage

Abstract

This invention discloses a power control method, system, and device for power energy storage, relating to the field of power system dispatching technology. The method includes: real-time acquisition of DC bus voltage and operating data of each energy storage unit; calculation of the average state of charge (SOC) of each unit based on the SOC of each unit; calculation of the SOC deviation between each unit and the average SOC; combining the average SOC, deviation, and output current direction, and obtaining the SOC compensation resistor for each unit through power constraint and equalization collaborative calculation; obtaining the correction voltage for each energy storage unit through coordinated regulation of bus voltage, compensation resistor, and output current; and generating a DC / DC converter modulation signal based on the correction voltage. This invention, through a distributed regulation mechanism that coordinates SOC equalization and bus voltage optimization, effectively offsets control deviations caused by inconsistencies between individual units, accurately achieving synchronous equalization and voltage stability regulation of multiple energy storage units, thereby ensuring the long-term safe, stable, and reliable operation of the energy storage system.

Description

Technical Field

[0001] This invention belongs to the field of power system dispatching technology, and specifically relates to a power control method, system and equipment for power energy storage. Background Technology

[0002] With the rapid development of the power energy storage industry, energy storage systems have become an important supporting carrier for the construction of new power systems. In the large-scale application scenarios of power energy storage systems, precise control of energy storage power is the core key to ensuring the safe and efficient charging and discharging of energy storage, improving grid adaptability, and supporting the stable dispatch of the power system. It is widely involved in various power businesses such as grid peak shaving and frequency regulation, backup power supply, power consumption, and power support, and has become an indispensable core technology in the field of power energy storage, playing a decisive role in the overall operating efficiency and service life of energy storage.

[0003] Power control strategies for energy storage clusters generally employ a unified benchmark for output allocation, closed-loop control with fixed parameters, and a threshold-triggered passive balancing mode. Output power is distributed evenly according to overall power dispatch instructions, and passive correction compensation is only initiated when the remaining power deviation exceeds a limit threshold. Some improved schemes only add a simple unified correction compensation step to initially mitigate operational anomalies under extreme conditions. This traditional control method is characterized by its simple logic, low computational load, strong universality and adaptability, and ease of engineering implementation, and is widely used in existing energy storage power control scenarios.

[0004] However, in actual power storage operations involving multiple energy storage units operating in parallel and collaboratively, each unit generally exhibits inherent differences, including inconsistent initial remaining capacity, significant variations in rated capacity parameters, and individual differences in internal resistance characteristics. Under the operating logic of the aforementioned traditional power control methods, the capacity difference between energy storage units will continuously widen during repeated charging and discharging processes, making it impossible to autonomously achieve dynamic balancing. Simultaneously, power output allocation cannot be adapted to the capacity and real-time status of each energy storage unit, leading to a mismatch between power and unit carrying capacity. This results in small-capacity energy storage units operating under long-term overload conditions, while large-capacity energy storage units cannot fully utilize their capacity. Ultimately, this not only significantly reduces the overall power utilization efficiency and charging / discharging consistency of the energy storage cluster but also accelerates the aging and wear of individual energy storage modules, severely impacting the overall operational stability of the energy storage system. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of inaccurate regulation caused by individual differences in units in the multi-unit parallel and coordinated control scenario of power energy storage, which leads to the overall operational stability of the energy storage system. Therefore, this invention proposes a power control method, system and equipment for power energy storage.

[0006] In a first aspect of this invention, a power control method for electric energy storage is first proposed, the method comprising: The DC bus voltage and the operating status data of each energy storage unit are collected in real time; the operating status data includes the output current value, the output current direction, and the state of charge. The average state of charge (SOC) is calculated based on the SOC of each energy storage unit, and the SOC deviation between each energy storage unit and the average SOC is calculated. The state-of-charge compensation resistor for each energy storage unit is obtained by performing a combined calculation of power constraint and state-of-charge balance based on the average state of charge, the state-of-charge deviation value of each energy storage unit, and the direction of output current. The corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control of the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. Modulation signals are generated based on the correction voltage of each energy storage unit to control the DC / DC converter in each energy storage unit.

[0007] Optionally, the state-of-charge compensation resistor for each energy storage unit is obtained through a collaborative calculation of power constraint and state-of-charge equilibrium based on the average state of charge, the state-of-charge deviation value of each energy storage unit, and the direction of the output current. This includes: pass Calculate the state-of-charge (POC) compensation resistance; the target energy storage unit is any one of all energy storage units; where T is the POC compensation resistance. The reference state of charge compensation resistor, This represents the maximum rated capacity of the energy storage units within the system. Where n is the rated capacity of the target energy storage unit itself, and n is the global adjustment coefficient. It is a dynamically variable adjustment coefficient. The value is the state of charge deviation. When the output current is in the positive direction, A is 1, and when the output current is in the negative direction, A is -1.

[0008] This solution can dynamically calculate the state-of-charge compensation resistor by combining current direction, capacity difference and state-of-charge deviation, taking into account power constraints and state-of-charge balance, adapting to all charging and discharging conditions, accurately balancing the state of each energy storage unit, suppressing inconsistencies, avoiding overcharging and over-discharging, and improving the operational stability and overall service life of the energy storage system.

[0009] Optionally, the formula for calculating the dynamic variable adjustment coefficient is: ;in, Here, n is the dynamic variable adjustment coefficient, and n is the global adjustment coefficient. This is the deviation value of the state of charge. The average state of charge, It is the bias adjustment constant and its value range is 0 < <1.

[0010] This scheme dynamically calculates the variable adjustment coefficient based on the state of charge deviation and the average state of charge. The larger the deviation, the stronger the adjustment. The bias constant can avoid over-adjustment when the deviation is small and prevent the denominator from being zero. It takes into account both the global benchmark and individual differences, and has a sensitive response and strong stability. It can accurately adapt to all working conditions of energy storage state of charge equilibrium.

[0011] Optionally, the corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control based on the bus voltage, the state-of-charge compensation resistor of each energy storage unit, and the output current, including: The voltage deviation is obtained by multiplying the state-of-charge compensation resistor of each energy storage unit with the corresponding output current. The difference between the DC bus voltage and the preset DC bus reference voltage is calculated to obtain the bus voltage correction amount; An optimization objective function is constructed based on the bus voltage correction and the voltage deviation of each energy storage unit; With the goal of minimizing the optimization objective function, the voltage compensation amount of each energy storage unit is iteratively calculated based on the voltage deviation of each energy storage unit and the bus voltage correction amount, according to the preset consensus algorithm. For each energy storage unit, the corrected voltage of each energy storage unit is obtained by coordinating and correcting the voltage deviation and voltage compensation.

[0012] This scheme combines the bus voltage deviation and the state of charge compensation characteristics of the energy storage unit to construct the optimization target. The voltage compensation amount is solved iteratively through the consensus algorithm. It simultaneously takes into account the dual objectives of bus voltage stability and unit charge balance. It can achieve coordinated and precise control of bus voltage stabilization and consistency of multiple energy storage units. The correction process converges smoothly and effectively suppresses differences between units and bus voltage fluctuations.

[0013] Optionally, with the goal of minimizing the optimization objective function, and based on a preset consensus algorithm, the voltage compensation amount of each energy storage unit is iteratively calculated according to the voltage deviation of each energy storage unit and the bus voltage correction amount, including: Step 1: Construct the communication topology relationship between all energy storage units to obtain the directed communication topology, and generate a directed graph Laplace matrix based on the directed communication topology; the directed graph Laplace matrix is ​​used to uniquely define the unidirectional communication adjacency objects and information transmission direction of each energy storage unit; Step 2: Determine the set of incoming and outgoing neighbor nodes of the target energy storage unit based on the directed graph Laplace matrix, and calculate the relative voltage deviation between the target energy storage unit and each node in the set of incoming and outgoing neighbor nodes; the target energy storage unit is any one of the energy storage units. Step 3: If there is a relative voltage deviation greater than or equal to a preset threshold, the voltage deviation of the target energy storage unit is sparsely transmitted to the nodes in the neighboring node set according to the unidirectional link defined by the directed communication topology. Step 4: Receive the voltage deviation sent by the neighboring node set corresponding to the target energy storage unit, and perform time delay compensation and anomaly removal processing on the voltage deviation of each node in the neighboring node set to obtain an effective voltage deviation set. Step 5: Perform coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set to obtain the voltage compensation amount; Step 6: Correct the voltage deviation of the target energy storage unit according to the effective voltage deviation set to obtain an updated voltage deviation, and use the updated voltage deviation as the new voltage deviation. Step 7: Calculate the value of the target energy storage unit's optimization objective function based on the bus voltage correction amount and the voltage deviation amount. If the difference between the sum of the function values ​​of all energy storage units in two adjacent iterations is greater than or equal to the preset convergence threshold, return to step 2 until the difference between the function values ​​of two adjacent iterations is less than the preset convergence threshold or the preset number of iterations is reached, and finally obtain the voltage compensation amount of each energy storage unit.

[0014] This solution balances bus voltage correction and voltage consistency balancing across multiple energy storage units. It features fast convergence, strong anti-interference capabilities, and effectively mitigates control errors caused by communication delays and data anomalies. It significantly improves the voltage balancing accuracy, operational stability, and distributed adaptability of the parallel energy storage system.

[0015] Optionally, the voltage compensation amount is obtained by performing coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction amount, and the effective voltage deviation set, including: The comprehensive voltage deviation is obtained by deviation coupling calculation based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set; The proportional voltage compensation increment is obtained by performing a difference balance calculation on the comprehensive voltage deviation. The constrained integral voltage compensation increment is obtained by performing integral calculation and amplitude limiting constraint processing on the comprehensive voltage deviation. The initial voltage compensation amount is obtained by weighting the proportional voltage compensation increment and the constrained integral voltage compensation increment. Based on the preset voltage constraint feasible region, the initial voltage compensation amount is substituted into the feasible region for boundary correction to obtain the voltage compensation amount.

[0016] This solution can quickly eliminate instantaneous voltage deviation and ensure dynamic response speed, while also effectively eliminating steady-state error, suppressing overshoot and overcompensation. It balances bus voltage stability and unit balance, offering high control precision and robustness, and avoiding the risk of voltage exceeding limits.

[0017] Optionally, for each energy storage unit, the corrected voltage for each energy storage unit is obtained by co-coupling correction based on the voltage deviation and voltage compensation, including: For a target energy storage unit, the first voltage is obtained by subtracting the voltage deviation of the target energy storage unit from the preset DC bus reference voltage; the target energy storage unit is any one of the energy storage units. The signs of the voltage deviation and voltage compensation of the target energy storage unit are compared. If the signs are the same, the absolute value of the voltage deviation and the absolute value of the voltage compensation are added together to obtain the first adjustment amount. If the signs are opposite, the absolute value of the difference between the absolute value of the voltage deviation and the absolute value of the voltage compensation is used as the first adjustment amount. The second voltage is obtained by algebraically summing the first voltage and the first adjustment amount according to the sign of the voltage deviation. The first difference is obtained by calculating the difference between the second voltage and the preset DC bus reference voltage; The signs of the first difference and the voltage compensation amount are compared. If the signs are the same, the second voltage is added to half the absolute value of the voltage compensation amount to obtain the third voltage; if the signs are opposite, the second voltage is subtracted from half the absolute value of the voltage compensation amount to obtain the third voltage. The theoretical boundary value is obtained by subtracting the voltage deviation from the preset DC bus reference voltage and adding the voltage compensation. The third voltage is compared with the theoretical boundary value; if the third voltage is between the preset DC bus reference voltage and the theoretical boundary value, the third voltage is directly output as the correction voltage; otherwise, the intermediate value between the theoretical boundary value and the third voltage is used as the correction voltage.

[0018] This solution ensures both the sensitivity of dynamic voltage regulation and a smooth transition during the regulation process, while strictly constraining the correction voltage within a reasonable range to avoid voltage overshoot, oscillation, and exceeding limits. It accurately matches the target bus reference voltage and effectively balances the individual balance of energy storage units with the stability of DC bus voltage.

[0019] In a second aspect of the invention, a power control system for power storage is provided, comprising: The acquisition module is used to acquire DC bus voltage and operating status data of each energy storage unit in real time; the operating status data includes output current value, output current direction and state of charge; The deviation value calculation module is used to calculate the average state of charge based on the state of charge of each energy storage unit, and to calculate the state of charge deviation value between the state of charge of each energy storage unit and the average state of charge. The resistance calculation module is used to perform a collaborative calculation of power constraint and state of charge balance based on the average state of charge, the state of charge deviation value of each energy storage unit, and the direction of output current to obtain the state of charge compensation resistance of each energy storage unit. The corrected voltage generation module is used to obtain the corrected voltage of each energy storage unit by coordinating and optimizing the control based on the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. The control module is used to generate modulation signals for controlling the DC / DC converter in each energy storage unit based on the correction voltage of each energy storage unit.

[0020] In a third aspect of the present invention, an electronic device is provided, comprising a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. Memory, used to store computer programs; When a processor executes a program stored in memory, it implements any of the steps described above.

[0021] The beneficial effects of this invention are as follows: This solution effectively offsets the control deviation caused by the inconsistency of individual units through a distributed control mechanism that optimizes the state of charge balance and bus voltage, accurately achieves synchronous balance and voltage stability control of multiple energy storage units, greatly improves the control accuracy and dynamic adaptability of energy storage clusters, and fundamentally ensures the long-term safe, stable and reliable operation of the energy storage system. Attached Figure Description

[0022] The present invention will now be further described with reference to the accompanying drawings.

[0023] Figure 1 A flowchart of a power control method for power storage provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the connection of the energy storage unit connected in parallel to the common DC bus according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a device provided in an embodiment of the present invention. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0025] 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.

[0026] This invention provides a power control method for electric energy storage. See also... Figure 1 , Figure 1 A flowchart of a power control method for electric energy storage provided in an embodiment of the present invention; see also Figure 2 , Figure 2 This is a schematic diagram illustrating the parallel connection of an energy storage unit to a common DC bus, as provided in an embodiment of the present invention. The method includes the following steps: S101 collects DC bus voltage and operating status data of each energy storage unit in real time; S102, calculate the average state of charge based on the state of charge of each energy storage unit, and calculate the state of charge deviation between the state of charge of each energy storage unit and the average state of charge. S103, based on the average state of charge, the state of charge deviation of each energy storage unit, and the direction of the output current, the state of charge compensation resistor of each energy storage unit is obtained by the joint calculation of power constraint and state of charge balance. S104, the corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control of the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. S105, generates a modulation signal for controlling the DC / DC converter in each energy storage unit based on the correction voltage of each energy storage unit; The operating status data includes the output current value, output current direction, and state of charge.

[0027] This invention provides a power control method for energy storage. This method involves real-time acquisition of bus voltage and energy storage unit operating data, calculation of state-of-charge (SOC) deviation, generation of compensation resistors based on operating conditions, optimization and correction of the bus voltage, and output of modulation signals to control the DC / DC converter. This invention can accurately compensate for individual differences in energy storage units, solving the problem of inaccurate regulation caused by inconsistencies between individual units when multiple energy storage units are connected in parallel. It balances the dual objectives of SOC balance and bus voltage stability, dynamically adapting to all charging and discharging conditions, thereby improving the overall operational stability of the energy storage system.

[0028] In one embodiment, the state-of-charge compensation resistor for each energy storage unit is obtained through a collaborative calculation of power constraint and state-of-charge equilibrium based on the average state of charge, the state-of-charge deviation value of each energy storage unit, and the direction of the output current. pass Calculate the state-of-charge (POC) compensation resistance; the target energy storage unit is any one of all energy storage units; where T is the POC compensation resistance. The reference state of charge compensation resistor, This represents the maximum rated capacity of the energy storage units within the system. Where n is the rated capacity of the target energy storage unit itself, and n is the global adjustment coefficient. It is a dynamically variable adjustment coefficient. This is the state of charge deviation value. When the output current direction is positive, A is 1, and when the output current direction is negative, A is -1.

[0029] In one implementation, when the output current is in the positive direction, the energy storage unit is in a discharging state; when the output current is in the negative direction, the energy storage unit is in a charging state.

[0030] In one implementation, the global adjustment coefficient n is a pre-tuned positive constant that remains fixed during operation; its function is to adjust the global adjustment coefficient. The overall adjustment range is scaled to a reference: the larger n is, the more the state-of-charge compensation resistor T affects the overall adjustment range. The higher the sensitivity, the faster the state of charge equalization speed; the smaller n is, the smoother the adjustment, the higher the power safety, but the slower the equalization speed.

[0031] In one implementation, the formula achieves coupled, coordinated, and synchronous parallel regulation of two control objectives: power constraint and state-of-charge (SOC) balance. The SOC compensation resistor directly determines the output power of the energy storage unit, and the output current I of the energy storage unit is related to the DC bus voltage. Satisfying Relationships ,in Given a fixed no-load reference voltage, the output power... When the bus voltage is basically constant, the state-of-charge compensation resistor and the output power of the energy storage unit have a clear inverse relationship. Therefore, the output power of each energy storage unit can be directly and accurately adjusted by dynamically controlling T.

[0032] In one implementation, This is used to normalize the rated capacity of the reference state-of-charge compensation resistor for each energy storage unit. Energy storage units with smaller rated capacities will receive a larger multiplication factor, and the reference value of their state-of-charge compensation resistor will be correspondingly increased; conversely, energy storage units with larger rated capacities will receive a smaller multiplication factor. This ensures that during steady-state operation, the output power of each energy storage unit can be distributed according to its rated capacity. Combined with the inverse relationship between T and power P, the larger the capacity of the unit, the smaller T and the greater the output power, thereby realizing the power sharing according to the capacity ratio.

[0033] In one implementation, It is the core of achieving the coupling and coordination of state of charge balance and power constraint. This index term dynamically adjusts the state of charge compensation resistor T according to the current state of charge deviation and charging / discharging direction of the energy storage unit, thereby changing the output power.

[0034] In one implementation, when the state of charge of the target energy storage unit deviates... When it is large, the absolute value of the exponent term Significantly greater than zero; taking the discharge condition as an example, if the state of charge of the energy storage unit is too high, then A value much less than 1 would theoretically significantly reduce T, leading to a sharp increase in output power. However, this implementation does not amplify power without limit at this stage. Instead, through the synergistic effect of the global adjustment coefficient and the dynamic variable adjustment coefficient, the change in the exponential term is constrained within a safe range, effectively keeping the state-of-charge compensation resistor at a relatively large value during this stage. This constraint effect ensures that even energy storage units with a high state of charge will not experience a sudden surge in output power, but will be actively limited to a safe range. Meanwhile, energy storage units with a low state of charge... Since it is much greater than 1, its T increases significantly, and the output power is correspondingly limited to a lower level.

[0035] In one implementation, as the state-of-charge (POC) equalization control progresses, the POCs of the various energy storage units gradually converge, and the deviation decreases. The exponent term gradually approaches zero. ≈1, the exponential adjustment effect weakens; at this stage, the sensitivity of the exponential term to small deviations in the state of charge is actually increased by using a dynamically variable adjustment coefficient, i.e. Follow The decrease in the state of charge (SCC) leads to an increase in the SCC, thus transforming minute differences in SCC into significant changes in the SCC compensation resistance. Specifically, when the SCC deviation approaches zero, the unit with a slightly higher SCC experiences a significant decrease in T and a significant increase in output power; conversely, the unit with a slightly lower SCC experiences a significant increase in T and a significant decrease in output power. This progressive release of power constraint margin design allows for an improved regulation response rate in the later stages of regulation, accelerating the final convergence of the global SCC with a larger power regulation amplitude, ensuring that all energy storage units quickly reach a consistent SCC level.

[0036] In one implementation, this scheme abandons the separate control architecture where power constraints and state-of-charge (POC) equilibrium are independent. Instead, it achieves coupled, coordinated, and synchronous parallel regulation of the two control objectives—power constraints and POC equilibrium—through a unified POC compensation resistor T. During operation with significant POC deviations, this scheme prioritizes system power safety, actively constraining the output power amplitude of each energy storage unit, suppressing transient power surges, and smoothly advancing the global POC equilibrium regulation process. As the POC deviations of each energy storage unit gradually narrow, the power constraint margin is progressively released, improving the regulation response rate and accelerating global POC convergence. Simultaneously, this scheme differentiates between the charging and discharging operation conditions of the energy storage units throughout the process, configuring two sets of differentiated calculation formulas for precise adaptation and regulation. This effectively avoids the risks of power exceeding limits and system oscillations during the entire POC equilibrium regulation process, reliably ensuring the operational stability and efficient regulation of the energy storage system.

[0037] In one embodiment, the formula for calculating the dynamic variable adjustment coefficient is: ;in, Here, n is the dynamic variable adjustment coefficient, and n is the global adjustment coefficient. This is the deviation value of the state of charge. The average state of charge, It is the bias adjustment constant and its value range is 0 < <1.

[0038] In one implementation, Reflects Absolute value of deviation from normalized state of charge The relationship is inversely proportional; when the state of charge deviation between energy storage units is large, that is... When the value is high, the reciprocal of this term It will decrease, thus making The value approaches the bias constant. When the state of charge deviation approaches zero, i.e. When →0, the term approaches infinity, thus... Significantly increased; when the state of charge deviation is large, If the value decreases automatically, then the overall adjustment range of T will be affected. The reduction in charge level leads to compression; this compression effect strictly limits the output increase of a single energy storage unit within a unit control cycle, effectively avoiding instantaneous power surges caused by high state of charge, and preventing dangerous operating conditions such as overload, rapid charging or discharging of the energy storage unit; when the state of charge deviation approaches zero, The value automatically increases. At this time, the adjustment range of the exponential term is due to... The increase in power significantly improves the efficiency of the state of charge (SCC) compensation resistor T, making even small differences in SCC sensitive to changes in the SCC compensation resistor T. This process gradually relaxes the power constraint margin, allowing the energy storage unit to accurately complete the balancing process with small and rapid power adjustments, thereby accelerating the final convergence of the global SCC and balancing the speed and accuracy of the balancing process.

[0039] In one embodiment, the corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control based on the bus voltage, the state-of-charge compensation resistor of each energy storage unit, and the output current, including: The voltage deviation is obtained by multiplying the state-of-charge compensation resistor of each energy storage unit with the corresponding output current. The difference between the DC bus voltage and the preset DC bus reference voltage is used to obtain the bus voltage correction amount; An optimization objective function is constructed based on the bus voltage correction and the voltage deviation of each energy storage unit; With the goal of minimizing the objective function, the voltage compensation of each energy storage unit is iteratively calculated based on the voltage deviation of each energy storage unit and the bus voltage correction based on the preset consensus algorithm. For each energy storage unit, the corrected voltage of each energy storage unit is obtained by coordinating and correcting the voltage deviation and voltage compensation.

[0040] In one implementation, the objective function is optimized as follows: ;in, Let be the voltage compensation amount for the i-th energy storage unit. Let be the voltage deviation of the i-th energy storage unit. This is the DC bus voltage. The preset DC bus reference voltage is N, where N is the total number of energy storage units.

[0041] In one implementation, the transformation from physical quantity to deviation quantity is the basis for subsequent optimization. The introduction of bus voltage correction quantity ensures that global voltage information participates in local decision-making. The combination of optimization objective function and consensus algorithm realizes the efficiency of distributed solution. Finally, the cooperative coupling correction solves the possible directional conflict and amplitude imbalance between voltage deviation quantity and compensation quantity, avoiding over-adjustment or under-adjustment caused by simple linear superposition.

[0042] In one embodiment, with the objective function minimization as the goal, the voltage compensation amount of each energy storage unit is iteratively calculated based on a preset consensus algorithm, according to the voltage deviation of each energy storage unit and the bus voltage correction amount. Step 1: Construct the communication topology relationship between all energy storage units to obtain the directed communication topology, and generate a directed graph Laplace matrix based on the directed communication topology; the directed graph Laplace matrix is ​​used to uniquely define the unidirectional communication adjacency objects and information transmission direction of each energy storage unit; Step 2: Determine the set of incoming and outgoing neighbor nodes of the target energy storage unit based on the directed graph Laplace matrix, and calculate the relative voltage deviation between the target energy storage unit and each node in the set of incoming and outgoing neighbor nodes; the target energy storage unit is any one of the energy storage units. Step 3: If there is a relative voltage deviation greater than or equal to a preset threshold, the voltage deviation of the target energy storage unit is sparsely transmitted to the nodes in the neighboring node set according to the unidirectional link defined by the directed communication topology. Step 4: Receive the voltage deviation sent by the neighboring node set corresponding to the target energy storage unit, and perform time delay compensation and anomaly removal processing on the voltage deviation of each node in the neighboring node set to obtain the effective voltage deviation set. Step 5: Perform coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set to obtain the voltage compensation amount; Step 6: Correct the voltage deviation of the target energy storage unit based on the effective voltage deviation set to obtain the updated voltage deviation, and use the updated voltage deviation as the new voltage deviation. Step 7: Calculate the value of the objective function of the target energy storage unit based on the bus voltage correction and voltage deviation. If the difference between the sum of the function values ​​of all energy storage units in two adjacent iterations is greater than or equal to the preset convergence threshold, return to step 2 until the difference between the function values ​​of two adjacent iterations is less than the preset convergence threshold or the preset number of iterations is reached, and finally obtain the voltage compensation amount of each energy storage unit.

[0043] In one implementation, the preset convergence threshold and the preset number of iterations are set by the technician, and can be 0.1 and 100 times respectively.

[0044] In one implementation, any energy storage unit is taken as the target energy storage unit. Based on the directed communication topology and the directed graph Laplace matrix, the set of incoming and outgoing neighbor nodes corresponding to the unit are defined. First, the relative voltage deviation between the target energy storage unit and each incoming neighbor node is calculated. When any relative voltage deviation reaches a preset threshold, it indicates that there is a significant difference in the voltage operating status between units and the system consistency is unbalanced. At this time, according to the unidirectional transmission path constrained by the directed communication topology, the voltage deviation of the target energy storage unit is sparsely sent only to the nodes in the outgoing neighbor node set. This adopts an event-triggered on-demand communication mode to avoid the waste of communication resources caused by continuous transmission throughout the day. At the same time, it strictly follows the unidirectional adjacency transmission rule, and only shares the local deviation data to the downstream neighboring units. This provides an interactive basis for each energy storage unit to subsequently integrate neighborhood data, correct its own parameters, and calculate voltage compensation, ensuring the orderly implementation of distributed collaborative control of multiple energy storage units and gradually realizing the global voltage collaborative convergence.

[0045] In one implementation, the delay compensation process involves first acquiring the transmission time of the voltage deviation of neighboring nodes and the reception time of the target energy storage unit, calculating the time difference to determine the transmission delay; then, based on a preset voltage change fitting model, performing time-series extrapolation correction on the original voltage deviation to compensate for voltage fluctuation offset within the transmission interval; next, referring to the adjacent iteration deviation change trend, introducing a time-series correction coefficient to linearly correct lag error and match the real-time timing of the system; finally, outputting the time-series aligned neighboring node voltage deviation to eliminate data misalignment caused by communication delay; the anomaly removal process involves setting dual thresholds for single-node fluctuation and multi-node intervals as anomaly judgment criteria; verifying the voltage deviation of neighboring nodes one by one, and initially judging a single-point anomaly if the fluctuation of a single set of data exceeds the limit; combining the overall data distribution pattern, defining discrete data in the deviation interval as global anomalies; directly removing invalid data such as fault distortion and numerical jumps, and using neighborhood mean interpolation correction for slightly deviated critical data; finally, integrating to form an effective voltage deviation set.

[0046] In one implementation, the correction process involves first reading the effective voltage deviation set after time delay compensation and anomaly removal, extracting the voltage deviation data of all neighboring nodes with compliant timing alignment, and calculating the average voltage deviation of the entire neighborhood as a collaborative reference benchmark; then, calculating the deviation offset between the target energy storage unit's current original voltage deviation and the neighborhood average, introducing a preset convergence correction weight, and performing progressive weighted alignment correction on the original voltage deviation of the local unit to reduce the voltage deviation gap between the local unit and the entire neighborhood, thereby obtaining the updated voltage deviation.

[0047] In one embodiment, the voltage compensation amount is obtained by performing coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction amount, and the effective voltage deviation set, including: The comprehensive voltage deviation is obtained by deviation coupling calculation based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set. The proportional voltage compensation increment is obtained by performing a difference balance calculation on the overall voltage deviation. The constrained integral voltage compensation increment is obtained by performing integral calculation and amplitude limiting processing on the comprehensive voltage deviation. The initial voltage compensation amount is obtained by weighting the proportional voltage compensation increment and the constrained integral voltage compensation increment. Based on the preset voltage constraint feasible region, the initial voltage compensation amount is substituted into the feasible region for boundary correction to obtain the voltage compensation amount.

[0048] In one implementation, the difference balance calculation process involves comparing the comprehensive voltage deviation with the system's expected reference deviation, performing linear following calculations in conjunction with a preset proportional adjustment coefficient to quickly respond to instantaneous deviation fluctuations and generate a proportional voltage compensation increment. The integral calculation and amplitude limiting constraint processing involve performing cumulative integral calculations on the comprehensive voltage deviation generated in each iteration to continuously offset the system's static residual error, and then applying amplitude limiting constraint processing to the integral output result to strictly limit the integral output within a preset safe output range, avoiding integral saturation, overshoot, and numerical overflow, thus obtaining the constrained integral voltage compensation increment.

[0049] In one implementation, the boundary correction process involves determining whether the initial voltage compensation exceeds the upper and lower limits of the feasible region. If it exceeds the limits, it is directly clamped and corrected to the boundary extreme value. If it is within the range, the original calculated value is retained. After the boundary correction is completed, the final voltage compensation is output in a compliant, stable manner that meets the system voltage operating limits.

[0050] In one embodiment, for each energy storage unit, the corrected voltage of each energy storage unit is obtained by co-coupling correction based on the voltage deviation and voltage compensation, including: For the target energy storage unit, the first voltage is obtained by subtracting the voltage deviation of the target energy storage unit from the preset DC bus reference voltage; the target energy storage unit is any one of the energy storage units. The signs of the voltage deviation and voltage compensation of the target energy storage unit are compared. If the signs are the same, the absolute value of the voltage deviation and the absolute value of the voltage compensation are added together to obtain the first adjustment amount. If the signs are opposite, the absolute value of the difference between the absolute value of the voltage deviation and the absolute value of the voltage compensation is used as the first adjustment amount. The second voltage is obtained by algebraically summing the first voltage and the first adjustment amount according to the sign of the voltage deviation. The first difference is obtained by calculating the difference between the second voltage and the preset DC bus reference voltage; The signs of the first difference and the voltage compensation amount are compared. If the signs are the same, the second voltage is increased by half the absolute value of the voltage compensation amount to obtain the third voltage. If the signs are opposite, the second voltage is decreased by half the absolute value of the voltage compensation amount to obtain the third voltage. The theoretical boundary value is obtained by subtracting the voltage deviation from the preset DC bus reference voltage and adding the voltage compensation. The third voltage is compared with the theoretical boundary value. If the third voltage is between the preset DC bus reference voltage and the theoretical boundary value, the third voltage is directly output as the correction voltage. Otherwise, the intermediate value between the theoretical boundary value and the third voltage is used as the correction voltage.

[0051] In one implementation, the voltage deviation always causes the bus voltage to shift downward to limit power, while the voltage compensation can be positive or negative, leading to potential directional conflicts and amplitude imbalances. This method first compares the signs of the two to achieve differentiated coupling calculations of the control quantities, and then iteratively optimizes the voltage output value through two-level hierarchical progressive fine adjustment. This process effectively suppresses overshoot or reverse offset that may occur during the first correction. Finally, the theoretical boundary value is obtained by subtracting the voltage deviation from the preset DC bus reference voltage and adding the voltage compensation. The theoretical voltage boundary is calculated by combining the deviation and compensation, and the voltage is segmented according to the interval position of the second voltage relative to the boundary, reasonably limiting the amplitude to obtain a corrected voltage that balances optimality and safety. This process coordinates the voltage deviation and compensation through direction discrimination, avoiding mutual cancellation between the two types of control effects and ensuring accurate and reasonable voltage correction direction. With the help of the dynamic amplitude adjustment logic, the method flexibly realizes same-direction enhancement, opposite-direction balancing, and half-value buffer control according to the actual operating conditions, balancing dynamic response speed and the smoothness of operating condition switching. The output characteristics are optimized by a second closed-loop correction, which effectively suppresses voltage surges and system oscillations. Combined with boundary constraints, voltage limiting control is completed, so that the corrected voltage is stably placed within a reasonable operating range, which significantly improves the system's operational safety and anti-disturbance capability.

[0052] This invention also provides an electronic device, such as... Figure 3 As shown, it includes a processor 301, a communication interface 302, a memory 303, and a communication bus 304, wherein the processor 301, the communication interface 302, and the memory 303 communicate with each other through the communication bus 304. Memory 303 is used to store computer programs; When processor 301 executes a program stored in memory 303, it performs the following steps: The DC bus voltage and the operating status data of each energy storage unit are collected in real time; the operating status data includes the output current value, the output current direction, and the state of charge. The average state of charge (SOC) is calculated based on the SOC of each energy storage unit, and the SOC deviation between each energy storage unit and the average SOC is calculated. The state-of-charge compensation resistor for each energy storage unit is obtained by performing a combined calculation of power constraint and state-of-charge balance based on the average state of charge, the state-of-charge deviation value of each energy storage unit, and the direction of output current. The corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control of the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. Modulation signals are generated based on the correction voltage of each energy storage unit to control the DC / DC converter in each energy storage unit.

[0053] The communication interface is used for communication between the above-mentioned devices and other devices.

[0054] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0055] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be 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, or discrete hardware components.

[0056] The foregoing has described one embodiment of the present invention in detail, but this content is merely a preferred embodiment and should not be considered as limiting the scope of the present invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the scope of the claims of this invention.

Claims

1. A power control method for electric energy storage, characterized in that, The method includes: The DC bus voltage and the operating status data of each energy storage unit are collected in real time; the operating status data includes the output current value, the output current direction, and the state of charge. The average state of charge (SOC) is calculated based on the SOC of each energy storage unit, and the SOC deviation between each energy storage unit and the average SOC is calculated. pass Calculate the state-of-charge (POC) compensation resistance; the target energy storage unit is any one of all energy storage units; where T is the POC compensation resistance. The reference state of charge compensation resistor, This represents the maximum rated capacity of the energy storage units within the system. Where n is the rated capacity of the target energy storage unit itself, and n is the global adjustment coefficient. It is a dynamically variable adjustment coefficient. The state of charge deviation value is A. When the output current direction is positive, A is 1; when the output current direction is negative, A is -1. The formula for calculating the dynamic variable adjustment coefficient is as follows: ;in, Here, n is the dynamic variable adjustment coefficient, and n is the global adjustment coefficient. This is the deviation value of the state of charge. The average state of charge, It is the bias adjustment constant and its value range is 0 < <1; The state-of-charge compensation resistor for each energy storage unit is obtained by performing a combined calculation of power constraint and state-of-charge balance based on the average state of charge, the state-of-charge deviation value of each energy storage unit, and the direction of output current. The corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control of the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. Modulation signals are generated based on the correction voltage of each energy storage unit to control the DC / DC converter in each energy storage unit.

2. The power control method for power storage according to claim 1, characterized in that, The corrected voltage of each energy storage unit is obtained by coordinating and optimizing the control based on the bus voltage, the state-of-charge compensation resistor of each energy storage unit, and the output current. The voltage deviation is obtained by multiplying the state-of-charge compensation resistor of each energy storage unit with the corresponding output current. The difference between the DC bus voltage and the preset DC bus reference voltage is calculated to obtain the bus voltage correction amount; An optimization objective function is constructed based on the bus voltage correction and the voltage deviation of each energy storage unit; With the goal of minimizing the optimization objective function, the voltage compensation amount of each energy storage unit is iteratively calculated based on the voltage deviation of each energy storage unit and the bus voltage correction amount, according to the preset consensus algorithm. For each energy storage unit, the corrected voltage of each energy storage unit is obtained by coordinating and correcting the voltage deviation and voltage compensation.

3. The power control method for power storage according to claim 2, characterized in that, With the objective function being minimized, and based on a preset consensus algorithm, the voltage compensation amount for each energy storage unit is iteratively calculated according to the voltage deviation of each energy storage unit and the bus voltage correction amount, including: Step 1: Construct the communication topology relationship between all energy storage units to obtain the directed communication topology, and generate a directed graph Laplace matrix based on the directed communication topology; the directed graph Laplace matrix is ​​used to uniquely define the unidirectional communication adjacency objects and information transmission direction of each energy storage unit; Step 2: Determine the set of incoming and outgoing neighbor nodes of the target energy storage unit based on the directed graph Laplace matrix, and calculate the relative voltage deviation between the target energy storage unit and each node in the set of incoming and outgoing neighbor nodes; the target energy storage unit is any one of the energy storage units. Step 3: If there is a relative voltage deviation greater than or equal to a preset threshold, the voltage deviation of the target energy storage unit is sparsely transmitted to the nodes in the neighboring node set according to the unidirectional link defined by the directed communication topology. Step 4: Receive the voltage deviation sent by the neighboring node set corresponding to the target energy storage unit, and perform time delay compensation and anomaly removal processing on the voltage deviation of each node in the neighboring node set to obtain an effective voltage deviation set. Step 5: Perform coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set to obtain the voltage compensation amount; Step 6: Correct the voltage deviation of the target energy storage unit according to the effective voltage deviation set to obtain an updated voltage deviation, and use the updated voltage deviation as the new voltage deviation. Step 7: Calculate the value of the target energy storage unit's optimization objective function based on the bus voltage correction amount and the voltage deviation amount. If the difference between the sum of the function values ​​of all energy storage units in two adjacent iterations is greater than or equal to the preset convergence threshold, return to step 2 until the difference between the function values ​​of two adjacent iterations is less than the preset convergence threshold or the preset number of iterations is reached, and finally obtain the voltage compensation amount of each energy storage unit.

4. The power control method for power storage according to claim 3, characterized in that, The voltage compensation amount is obtained by performing coupled control calculations based on the voltage deviation of the target energy storage unit, the bus voltage correction amount, and the effective voltage deviation set, including: The comprehensive voltage deviation is obtained by deviation coupling calculation based on the voltage deviation of the target energy storage unit, the bus voltage correction, and the effective voltage deviation set; The proportional voltage compensation increment is obtained by performing a difference balance calculation on the comprehensive voltage deviation. The constrained integral voltage compensation increment is obtained by performing integral calculation and amplitude limiting constraint processing on the comprehensive voltage deviation. The initial voltage compensation amount is obtained by weighting the proportional voltage compensation increment and the constrained integral voltage compensation increment. Based on the preset voltage constraint feasible region, the initial voltage compensation amount is substituted into the feasible region for boundary correction to obtain the voltage compensation amount.

5. A power control method for power storage according to claim 2, characterized in that, For each energy storage unit, the corrected voltage for each energy storage unit is obtained by coordinating and correcting the voltage deviation and voltage compensation. For a target energy storage unit, the first voltage is obtained by subtracting the voltage deviation of the target energy storage unit from the preset DC bus reference voltage; the target energy storage unit is any one of the energy storage units. The signs of the voltage deviation and voltage compensation of the target energy storage unit are compared. If the signs are the same, the absolute value of the voltage deviation and the absolute value of the voltage compensation are added together to obtain the first adjustment amount. If the signs are opposite, the absolute value of the difference between the absolute value of the voltage deviation and the absolute value of the voltage compensation is used as the first adjustment amount. The second voltage is obtained by algebraically summing the first voltage and the first adjustment amount according to the sign of the voltage deviation. The first difference is obtained by calculating the difference between the second voltage and the preset DC bus reference voltage; The signs of the first difference and the voltage compensation amount are compared. If the signs are the same, the second voltage is added to half the absolute value of the voltage compensation amount to obtain the third voltage; if the signs are opposite, the second voltage is subtracted from half the absolute value of the voltage compensation amount to obtain the third voltage. The theoretical boundary value is obtained by subtracting the voltage deviation from the preset DC bus reference voltage and adding the voltage compensation. The third voltage is compared with the theoretical boundary value; if the third voltage is between the preset DC bus reference voltage and the theoretical boundary value, the third voltage is directly output as the correction voltage; otherwise, the intermediate value between the theoretical boundary value and the third voltage is used as the correction voltage.

6. A power control system for electric energy storage, characterized in that, The system includes: The acquisition module is used to acquire DC bus voltage and operating status data of each energy storage unit in real time; the operating status data includes output current value, output current direction and state of charge; The deviation value calculation module is used to calculate the average state of charge based on the state of charge of each energy storage unit, and to calculate the state of charge deviation value between the state of charge of each energy storage unit and the average state of charge. Resistance calculation module, used to calculate resistance through Calculate the state-of-charge (POC) compensation resistance; the target energy storage unit is any one of all energy storage units; where T is the POC compensation resistance. The reference state of charge compensation resistor, This represents the maximum rated capacity of the energy storage units within the system. Where n is the rated capacity of the target energy storage unit itself, and n is the global adjustment coefficient. It is a dynamically variable adjustment coefficient. The state of charge deviation value is A. When the output current direction is positive, A is 1; when the output current direction is negative, A is -1. The formula for calculating the dynamic variable adjustment coefficient is as follows: ;in, Here, n is the dynamic variable adjustment coefficient, and n is the global adjustment coefficient. This is the deviation value of the state of charge. The average state of charge, It is the bias adjustment constant and its value range is 0 < <1; The corrected voltage generation module is used to obtain the corrected voltage of each energy storage unit by coordinating and optimizing the control based on the bus voltage, the state-of-charge compensation resistor of each energy storage unit and the output current. The control module is used to generate modulation signals for controlling the DC / DC converter in each energy storage unit based on the correction voltage of each energy storage unit.

7. An electronic device, characterized in that, include: Memory, used to store executable instructions; A processor, when executing executable instructions stored in the memory, implements a method as described in any one of claims 1 to 5.

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