Flow battery distributed energy storage method and system

Abstract

The application relates to the technical field of energy storage, and provides a liquid flow battery distributed energy storage method and system.The method comprises the following steps: connecting a plurality of distributed liquid flow battery stack nodes to centralized positive electrolyte storage tanks and negative electrolyte storage tanks through parallel pipe networks respectively, so that all the stack nodes share electrolyte; and performing cross-node hydraulic control according to state data and power demand of each stack node.Through the decoupling architecture of centralized electrolyte storage and distributed stacks, the application reduces initial investment and land occupation area of the system, improves electrolyte utilization rate and system flexibility, and can be widely applied to new energy station, industrial park, data center and user-side energy storage scenes and the like.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a distributed energy storage method and system using flow batteries. Background Technology

[0002] With a high proportion of renewable energy connected to the grid, large-scale electrochemical energy storage has become one of the important technologies for smoothing fluctuations in wind and solar power output, providing frequency regulation and peak shaving support, and peak shaving and valley filling on the user side. Flow batteries, especially all-vanadium redox flow batteries, have advantages such as relatively independent and scalable power and capacity, long cycle life, high safety, and suitability for stationary long-term energy storage. They are suitable for scenarios such as new energy power plants, industrial parks, data centers, building microgrids, and user-side energy storage.

[0003] Existing flow battery systems employ a tightly coupled structure where one stack corresponds to one set of positive and negative electrode storage tanks and a circulation pump. This results in high investment costs and a large footprint, which to some extent limits their large-scale promotion and application scenarios. Summary of the Invention

[0004] This invention provides a distributed energy storage method and system for flow batteries, addressing the drawbacks of high investment costs and large footprint caused by the tightly coupled structure of existing technologies where one fuel cell stack corresponds to one storage tank. This invention, through a decoupled architecture of centralized electrolyte storage and distributed fuel cell stacks, reduces initial system investment and footprint, improves electrolyte utilization and system flexibility, and can be widely applied in scenarios such as new energy power plants, industrial parks, data centers, and user-side energy storage.

[0005] This invention provides a distributed energy storage method for flow batteries, comprising: connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank respectively through a parallel pipeline network, so that all stack nodes share the electrolyte; and performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0006] According to a distributed energy storage method for flow batteries provided by the present invention, the step of connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank respectively through a parallel pipeline network includes: each stack node is connected to the positive electrolyte supply main pipe and the positive electrolyte return main pipe through a positive electrolyte supply branch and a positive electrolyte return branch, and is connected to the negative electrolyte supply main pipe and the negative electrolyte return main pipe through a negative electrolyte supply branch and a negative electrolyte return branch, wherein the positive electrolyte supply main pipe and the negative electrolyte supply main pipe are respectively connected to the positive electrolyte storage tank and the negative electrolyte storage tank.

[0007] According to a distributed energy storage method for flow batteries provided by the present invention, the cross-node hydraulic control based on the state data and power requirements of each stack node includes: calculating the target pressure-flow rate of the corresponding branch of each stack node based on the state data and power requirements of each stack node; calculating the minimum pressure envelope of the main pump based on the target pressure-flow rate of each branch, the hydraulic model of the pipeline network, and the stack pressure drop, and controlling the main pump to provide the minimum total pressure difference required for the first type of branch; the minimum pressure envelope satisfies the pressure-flow rate requirements of all nodes; controlling the branch valves of the second type of branch based on the measured pressure-flow rate and the target pressure-flow rate of the stack node; the pressure difference required for the second type of branch is less than the pressure difference required for the first type of branch.

[0008] The distributed energy storage method for flow batteries provided by the present invention further includes: performing positive and negative electrode flow balance control based on the positive and negative electrode flow deviation.

[0009] The distributed energy storage method for flow batteries provided by the present invention further includes: evaluating the hydraulic balance of branches using a branch flow balance index, and adaptively correcting the hydraulic balance of branches based on changes in the flow of each branch.

[0010] The distributed energy storage method for flow batteries provided by the present invention further includes: adding a local liquid storage buffer tank for stack nodes with state of charge disturbances.

[0011] The distributed energy storage method for flow batteries provided by the present invention further includes: performing electrical power scheduling and liquid flow control for each stack node at multiple time scales.

[0012] According to the distributed energy storage method for flow batteries provided by the present invention, the method for electrical power scheduling and hydraulic flow control of each stack node at multiple time scales includes: at the day-ahead optimization layer, adjusting the charging and discharging power plan of each stack node based on the output of new energy sources, load, electricity price, and user demand; at the intraday rolling layer, performing rolling correction on the charging and discharging power plan based on measured power data; and at the real-time power and hydraulic control layer, performing real-time power tracking, target pressure and flow calculation, pressure envelope calculation, main pump frequency conversion control, and branch valve closed-loop control based on the charging and discharging power plan corrected by the intraday rolling layer.

[0013] The distributed energy storage method for flow batteries provided by the present invention further includes: performing safety interlock control when there is an anomaly in the state data of the stack node.

[0014] This invention also provides a flow battery distributed energy storage system, wherein the system operates the aforementioned flow battery distributed energy storage method; the system includes: a centralized electrolyte storage module for centralized storage of electrolyte and provision of shared capacity; the centralized electrolyte storage module includes a centralized positive electrolyte storage tank and a negative electrolyte storage tank; a shared supply and return pipeline module for connecting each distributed stack node in parallel to the centralized electrolyte storage module so that all stack nodes share the electrolyte; a main pump module for providing electrolyte circulation driving force to the shared supply and return pipeline module; a distributed stack node module for realizing charge and discharge power output or absorption at each user side; the distributed stack node module includes multiple distributed stack nodes; and a control module for performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0015] The present invention provides a distributed energy storage method and system for flow batteries. By decoupling the centralized electrolyte storage and the distributed stack, the initial investment and footprint of the system are reduced, while the electrolyte utilization rate and system flexibility are improved. It can be widely used in scenarios such as new energy power plants, industrial parks, data centers and user-side energy storage. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic flowchart of a distributed energy storage method for flow batteries provided by the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of a flow battery distributed energy storage system provided by the present invention.

[0019] Figure 3 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0021] Traditional flow battery systems mostly employ a tightly coupled structure of one stack and one storage tank, meaning each energy storage module is equipped with independent positive and negative electrolyte storage tanks and a matching circulation pump. This redundant configuration of tanks, electrolytes, and pumps increases the overall system cost, limiting the economic viability for user-side, industrial and commercial, medium- and low-voltage power distribution networks, and short- to medium-term energy storage scenarios. The independently configured positive and negative electrolyte storage tanks are large, placing high demands on load-bearing capacity, dikes, corrosion resistance, maintenance access, and safety distances, making them unsuitable for space-constrained scenarios such as data centers, industrial parks, urban complexes, and underground building spaces. Because each storage tank is independent, the state of charge (SoC) and effective capacity of the electrolyte corresponding to each stack cannot be shared. This results in some terminal electrolytes being idle at high or low SoC, while other terminals are constrained by capacity and cannot continue charging or discharging, leading to low electrolyte utilization.

[0022] In distributed energy storage scenarios involving multiple users, multiple nodes, and multiple terminals, there is a lack of systematic solutions that integrate centralized liquid storage, distributed stacks, shared electrolyte, and cross-node hydraulic control as a whole.

[0023] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating a distributed energy storage method for flow batteries provided by the present invention.

[0024] This invention provides a distributed energy storage method using a flow battery, comprising: 101: Connect multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank through a parallel pipeline network, so that all stack nodes can share the electrolyte; 102: Perform cross-node hydraulic control based on the status data and power requirements of each fuel cell stack node.

[0025] This invention addresses the problems of high investment costs, large footprint, and inability to perform energy and capacity sharing between terminal systems caused by the tightly coupled structure of traditional flow battery systems consisting of a single fuel cell stack and a single storage tank. This invention constructs a low-cost, scalable, maintainable, and isolated supply and return network architecture between a centralized storage tank and multiple distributed fuel cell stacks.

[0026] This invention is applicable to flow battery systems where the positive and negative electrolytes require cyclic transport, such as vanadium redox flow batteries, iron-chromium flow batteries, and organic flow batteries. The flow battery is a vanadium redox flow battery. The distributed energy storage system for the flow battery includes a centralized electrolyte storage module, a shared supply and return electrolyte network module, a main pump module, distributed stack node modules, and a control module.

[0027] The centralized electrolyte storage module includes at least one positive electrode electrolyte storage tank. and at least one negative electrode electrolyte storage tank Both the positive and negative electrode storage tanks are equipped with level gauges, temperature sensors, online SoC monitoring modules, circulating mixing branches, replenishment ports, venting or inerting interfaces, overflow or emergency collection interfaces, and maintenance isolation valves. The storage tanks can be made of acid- and alkali-resistant and oxidation-resistant metal. A centralized storage module is used for centralized storage of electrolyte and to provide shared capacity. Subscripts or superscripts may also be used in formulas involving separate listings of positive and negative electrodes. Indicates positive circuit, This indicates the negative terminal circuit.

[0028] The shared supply and return fluid network module includes a positive electrode supply main, a positive electrode return main, a negative electrode supply main, and a negative electrode return main, as well as positive electrode supply branches, positive electrode return branches, negative electrode supply branches, and negative electrode return branches connecting each distributed fuel cell stack node. The positive and negative electrode inlets of each fuel cell stack node are connected to the corresponding supply mains via branches, and the positive and negative electrode outlets are connected to the corresponding return mains via branches. To reduce natural hydraulic imbalance, a parallel or quasi-parallel supply and return fluid arrangement can be preferentially adopted; for branches that cannot be arranged in a parallel manner due to site constraints, active balancing is achieved through the branch flow regulating valves and pressure feedback of this invention.

[0029] The main pump module includes a positive main liquid supply pump. and negative main liquid supply pump The preferred pump type is a corrosion-resistant variable frequency centrifugal pump, magnetic pump, or diaphragm pump. The main pump outlet is equipped with a main pipe pressure sensor, main pipe flow meter, check valve, and bypass valve; the main pump inlet is equipped with a filter, pressure sensor, and low-level interlock. For larger systems, a pump set configuration of one pump in operation and one on standby, or multiple pumps connected in parallel with variable frequency, can be used to meet the requirements of redundancy and high-efficiency operation under low load. The main pump module is used to provide the required differential pressure and total flow rate for each branch.

[0030] The distributed fuel cell node module includes a flow battery stack, positive and negative electrode branch pipe sections, a node detection module, a flow control valve, a local node controller, a power converter, a DC protection switch, and necessary local heat exchangers or local buffer tanks. On the user side, only the fuel cell stack and power conversion equipment can be installed, with the centralized liquid storage tank located in a unified equipment area, thus significantly reducing the space occupied on the user side. The distributed fuel cell node module is used to achieve charging and discharging power output or absorption at each user side.

[0031] The control module consists of an industrial computer, a PLC or edge controller, a communication network, and an optimized scheduling program, used to perform day-ahead, intraday, and real-time collaborative scheduling and cross-node hydraulic balance control.

[0032] This also includes a node detection and regulation module, which consists of pressure, flow, temperature, SoC, voltage, current, valve position sensors, and regulating valves. This module is used to achieve branch status observation, independent flow control, and fault isolation. This invention per distributed stack node... A modular node detection and regulation box is installed. This node detection and regulation box is connected to the positive and negative branches respectively, forming two sets of liquid circuit detection channels that are independent of each other but coordinated in control strategy.

[0033] In a preferred embodiment, multiple distributed flow battery stack nodes are connected to a centralized positive electrolyte storage tank and a negative electrolyte storage tank via a parallel pipeline network. This includes: each stack node is connected to the positive electrolyte supply main pipe and the positive electrolyte return main pipe via a positive electrolyte supply branch and a positive electrolyte return branch, and is connected to the negative electrolyte supply main pipe and the negative electrolyte return main pipe via a negative electrolyte supply branch and a negative electrolyte return branch, respectively. The positive electrolyte supply main pipe and the negative electrolyte supply main pipe are connected to the positive electrolyte storage tank and the negative electrolyte storage tank, respectively.

[0034] At each stack node At the inlet end, a branch inlet shut-off valve, a filter or screen, and an inlet pressure sensor (the detected value is expressed as...) are sequentially installed along the electrolyte flow direction. ), inlet temperature sensor (detection value expressed as Branch flow meter (detection value expressed as) ), electric flow control valve (detection value expressed as And necessary check valves. The flow regulating valve can be arranged downstream or upstream of the flow meter; preferably, the flow meter is arranged in a position that meets the straight pipe section requirements, and pressure sensors are arranged before and after the regulating valve or at the inlet / outlet of the fuel cell stack to distinguish between valve pressure drop, fuel cell stack pressure drop, and pipeline pressure drop. The number of fuel cell stack nodes connected to the shared electrolyte storage system is denoted as follows: In this context, "+" indicates the positive electrolyte circuit, and "-" indicates the negative electrolyte circuit.

[0035] At each stack node An outlet pressure sensor is installed at the outlet end (the detected value is expressed as...). ), outlet temperature sensor (detection value expressed as ), outlet flow meter (detection value expressed as ) and the return shut-off valve. By comparison and It can determine whether a branch is leaking or blocked; through calculation The actual voltage drop of the fuel cell stack and local pipe sections at the nodes can be obtained; by comparison It can determine the heat load and cooling requirements of the fuel cell stack.

[0036] Each node is equipped with a low-flow bypass sampling module. This module draws a small amount of electrolyte from the stack inlet or outlet, passes through a corrosion-resistant microchannel, temperature sensor, conductivity sensor, redox potential sensor, or open-circuit voltage detection cell, and returns to the return branch. This is used to estimate the branch electrolyte SoC, concentration changes, and electrolyte health status. For vanadium redox flow batteries, when the electrolyte concentrations at the positive and negative electrodes are approximately equal, the following temperature-compensated open-circuit voltage estimation relationship can be used as a method for online SoC estimation: , in, The open-circuit voltage is the sample voltage of the electrolyte at the positive and negative electrodes. This is the equivalent standard potential after temperature and acidity correction. The gas constant is Thermodynamic temperature This is the Faraday constant. In practical engineering, the above formula can be fused with offline calibration curves, conductivity, density, or coulomb integral results to improve the accuracy of SoC estimation.

[0037] The local node controller is preferably a small PLC, industrial microcontroller, or embedded controller. Its sampling period can be 0.1s to 2s, the flow closed-loop control period can be 0.2s to 5s, and the SoC estimation period can be 1s to 60s. The controller locally performs signal acquisition, filtering, valve opening calculation, over-limit protection, and communication, while simultaneously uploading the node status to the control module. The uploaded data packet may include the following state vectors: , in, This is the alarm status value for the node. For the first The node Extreme branch flow, and These are the node inlet pressure and outlet pressure, respectively. and These are the node inlet temperature and outlet temperature, respectively. It can contain input values, output values, or a combination of both; For the first The node The valve opening of the branch circuit can be monitored, and the alarm status can cover conditions such as leakage, blockage, sensor failure, overpressure, low liquid level, high temperature, and SoC over-limit. This is the fuel cell stack voltage. This represents the fuel cell current.

[0038] The key role of the aforementioned node detection hardware is to transform each distributed fuel cell stack from a simple passive branch into a hydraulic control node with measurable, adjustable, isolated, and diagnostic capabilities. After receiving the status of each node, the control module can issue control commands to the main pump and branch valves based on the network hydraulic model and the power requirements of each node. This invention performs specific detection of pressure, flow rate, temperature, system of quantization (SoC), electrical quantities, and fault status for each fuel cell stack node, and forms a closed loop with the detection hardware, branch valves, pump sets, and control module.

[0039] As a preferred embodiment, cross-node hydraulic control is performed based on the status data and power requirements of each fuel cell node, including: calculating the target pressure-flow rate of the corresponding branch of each fuel cell node based on the status data and power requirements of each fuel cell node; calculating the minimum pressure envelope of the main pump based on the target pressure-flow rate of each branch, the network hydraulic model, and the fuel cell pressure drop, and controlling the main pump to provide the minimum total pressure difference required for the first type of branch; the minimum pressure envelope satisfies the pressure-flow rate requirements of all nodes; controlling the branch valves of the second type of branch based on the measured pressure-flow rate and target pressure-flow rate of the fuel cell node; the pressure difference required for the second type of branch is less than the pressure difference required for the first type of branch.

[0040] Considering that when multiple fuel cell stacks are connected to the same centralized liquid storage module through a pipeline network, differences in branch length, pipe diameter, number of local bends, elevation, and fuel cell stack flow resistance can lead to excessive near-end flow and insufficient far-end flow, resulting in increased concentration polarization, local temperature rise, decreased efficiency, and even shortened service life of the fuel cell stack. To achieve dynamic hydraulic balance under different power conditions and different node operating states, this invention models the supply and return liquid pipeline network as a directed hydraulic network (pipeline hydraulic model) based on the network's hydraulic characteristics, consisting of main pipes, branches, valves, fuel cell stacks, filters, heat exchangers, and local pipe fittings. The pump set and control module form a closed loop. The invention also addresses how to establish a flow resistance model based on the network's hydraulic characteristics that can be used for design and control, providing the calculation relationships between pipe diameter, pump head, branch valve pressure drop, target flow rate, and pump consumption.

[0041] For each electrode electrolyte circuit , No. The volumetric flow rate of each fuel cell branch is The total flow rate of the supervisor is: , in, For the first The total flow rate is controlled by the highest level. For the first Bypass flow in the polar loop.

[0042] Pipeline pressure drop This includes frictional losses along the pipeline, local resistance losses, static pressure differences caused by elevation differences, valve throttling losses, and pressure drops in the internal flow channels of the fuel cell stack. For a pipe diameter of... , length is The sum of the local drag coefficients is The pressure drop of the pipe section can be expressed using the extended Bernoulli equation and the Darcy-Wiesbach equation as follows: , in, The density of the electrolyte. It is the acceleration due to gravity. The elevation difference between the entrance and exit of the branch road. The average flow velocity inside the pipe, is the friction coefficient along the friction path. Based on Reynolds number The relative roughness of the pipe wall is determined using Moody's diagrams, Colebrook formulas, or empirical engineering formulas; for scenarios where electrolyte viscosity changes significantly with temperature, a system can be established in the control module. Correction.

[0043] The pressure drop caused by the internal flow channels, collector plates, inlet and outlet manifolds, and porous electrodes of the flow battery stack can be equivalent to concentrated hydraulic resistance. The following model is preferably fitted through factory testing of the stack or on-site step flow tests: in, Reflects linear resistance under laminar or low-velocity flow conditions. This reflects the secondary resistance caused by turbulence, local contraction, and manifold distribution. For rapid engineering design, the fuel cell stack can also be used at its rated flow rate. Rated voltage drop Converted to equivalent secondary resistance : , No. Branch Road Total voltage drop of the electrode It can be written as: , in, For the first Branch Road Electrode voltage drop For the first Branch Road Electron stack voltage drop, For the first Branch Road Pressure drop across the extreme valve. For the first Branch Road Pressure drop of the polarity filter.

[0044] Valve pressure drop can be determined based on the valve manufacturer's specifications. or Curve calculation. In SI units, it can be written as: , in, Indicates valve opening degree The corresponding flow capacity. By fitting the valve opening, branch flow rate, and measured pressure difference online, the actual branch resistance can be obtained and the model can be corrected.

[0045] The target flow rate of the branch is determined by the real-time charge / discharge current of the stack, the number of individual cells in series in the stack, the concentration of active material, and the allowable single-pass SoC variation. For the first... There are 1 fuel cell stack, and the number of individual cells is 1. The absolute value of the current is The number of single-electron reactions is The effective concentration of active substances is One-way allows SoC to change to The theoretical minimum flow rate of the branch can be estimated by the following formula: , in, For the first Minimum stoichiometric flow rate for each fuel cell stack For the first Target flow rate setpoint for each fuel cell branch The safety factor or excess factor can be set according to temperature, SoC, stack aging status and allowable concentration polarization, and is typically between 1.1 and 3.0. The minimum circulation flow rate required to maintain wetting, venting, and thermal management of the fuel cell stack. If the concentration, viscosity, or flow channel structure of the positive and negative electrolytes differs, it can be calculated separately. and Electrochemical stability is maintained through positive and negative electrode flow matching constraints.

[0046] Pump consumption It can be calculated from the total flow rate, the pressure difference between the pump outlet and inlet, and the pump efficiency: , in, For the first The pressure difference between the outlet and inlet of the main pump, i.e., the head pressure provided by the electrolyte circulation pump. For the first Total flow rate For the first Extreme main pump speed, For the first The efficiency of the pump at the current speed and flow rate. For variable frequency pumps, under similar operating conditions, the flow rate, head, and shaft power approximately satisfy... .

[0047] Considering that the pump power consumption of a flow battery is related to the total flow rate, head, and pump efficiency, the pump power changes rapidly with the flow rate and head. If the pump speed is fixed according to the most unfavorable branch and rated flow rate, significant valve throttling losses and pump energy waste will occur under low load, partial battery stack shutdown, or large differences in branch demand.

[0048] This invention does not simply maintain a fixed high pressure, but rather calculates the minimum pressure envelope in real time based on the target pressure and flow rate of each branch and the hydraulic model of the pipe network, so that the main pump only provides the minimum total pipe pressure difference required by the branch that is most difficult to meet (the first type of branch): , In the formula, For the first Primary pump differential pressure setting value No. Minimum pressure drop of the control valve. The minimum valve pressure drop to ensure the control valve has a controllable margin. This provides a safety margin for pressure control. The strategy ensures that the distant or high-resistance branch (Type 1 branch) receives just the available differential pressure to meet the target flow rate, while the near or low-resistance branch (Type 2 branch) eliminates excess differential pressure through a closed-loop branch valve, thereby avoiding the main pump operating at its rated maximum head for extended periods.

[0049] When designing pipe diameter, first select the pipe diameter based on the allowable flow velocity, and then iteratively correct it through pressure drop verification. For main pipe design, it is recommended to use the maximum total flow rate of the entire system. Select branches based on the maximum flow of nodes. For low-pressure circulating pipelines containing acidic vanadium electrolyte, the initial flow velocity in the main pipe can be selected as 0.6 m / s to 1.5 m / s, and the flow velocity in the branches can be selected as 0.3 m / s to 1.0 m / s, to balance pressure drop, bubble removal, corrosion erosion, and construction costs. The initial pipe diameter selection formula is: , An example of a non-restricted calculation is as follows: Assume the system consists of 6 sets of 20kW fuel cell stacks, each with a rated voltage of approximately 56V and a rated current of approximately 357A. The number of individual cells connected in series in a single stack is... Effective concentration of active substances One-way allows SoC changes The target flow rate for a single pile is approximately: , When all 6 fuel cell stacks are running at rated speed simultaneously, the total flow rate of the single-pole main pipe is approximately If the effective pressure difference between the positive and negative main pumps is 180 kPa, the pump efficiency is... The total pump consumption of the two poles is approximately: , Compared to the rated power of the 120kW fuel cell stack, pump consumption accounts for approximately 3.0%. When the system is at 50% power or some nodes are out of service, this invention reduces pump consumption through four methods: target flow rate decreasing with current, minimum pressure envelope varying with the most unfavorable branch, main pump frequency conversion speed reduction, and branch valve throttling. Compared to operation at fixed pump speed and fixed high pressure differential, it can significantly reduce auxiliary energy consumption under non-rated operating conditions. The above values ​​are only for illustrating the calculation methods of the model and control method; actual designs can be modified based on fuel cell stack voltage drop, pipe diameter, pipe length, temperature, and electrolyte properties.

[0050] In a shared tank architecture, where the electrolyte circulates across multiple terminals, blockages, leaks, valve jamming, SoC malfunctions, or sensor drift at a single node can all impact the entire system. Existing solutions lack modular monitoring hardware for each fuel cell stack node, online identification of branch hydraulic parameters, inlet / outlet flow consistency verification, and cross-node fault isolation mechanisms. This invention, when multiple branches operate in parallel, ensures that each fuel cell stack receives an independent flow rate matching its real-time power, while simultaneously preventing overcurrent in near-end branches and undercurrent in far-end branches.

[0051] This invention employs a multi-layer control architecture with central pressure envelope control, independent closed-loop branch flow, and positive and negative pole coordinated matching to avoid the phenomenon of excessive near-end flow and insufficient far-end flow in the parallel connection of multiple branches.

[0052] The first layer is the target flow calculation layer. The control module calculates the flow rate based on the power commands from each node. fuel cell voltage Power conversion efficiency Calculate the target stack current based on the current operating mode: , Then, based on the aforementioned electrochemical flow rate formula, we obtain... and When a node is in standby, maintenance, or fault isolation state, The flow rate can be reduced to the minimum flow rate for liquid retention or set to zero and the branch valve closed.

[0053] The second layer is the main pump pressure control layer. The control module uses the model of each branch to calculate... The main pump speed is adjusted via a frequency converter. This increases the pressure in the main liquid supply pipe. With return main pressure The difference between the values ​​tracks the setpoint. This layer can employ PID control, feedforward + PID control, or model predictive control. One form of PID control is: , The third layer is a closed-loop flow control for branch valves. The local controller at each node compares the measured flow rate. With target traffic Adjust the opening of the branch valve To improve response speed, a combination of valve opening feedforward and PID feedback is preferred: , in, This means that the valve opening is calculated by working backward from the required flow capacity based on the valve calibration curve. It can be obtained by subtracting the stack pressure drop from the pressure before and after the valve or the total pressure difference between the supply and return fluids. When the branch pressure difference is insufficient, the valve is close to fully open but the flow rate is still low. The controller marks this branch as a pressure bottleneck branch and requests the control module to increase the main pump pressure envelope or reduce the flow demand of other branches.

[0054] As a preferred embodiment, it further includes: performing positive and negative electrode flow balance control based on the positive and negative electrode flow deviation.

[0055] The fourth layer involves positive and negative electrode flow matching and anti-bias flow constraints. For each fuel cell node, the control module calculates the positive and negative electrode flow deviation in real time. , in, for , and The maximum value in. When When the set threshold is exceeded, the system will prioritize adjusting the valve on the larger side or limiting the current of the fuel cell stack to avoid severe mismatch between the positive and negative electrode flow rates, which could lead to local concentration polarization, gas entrainment, or electrolyte imbalance.

[0056] As a preferred embodiment, the method further includes: evaluating the hydraulic balance of the branches using the branch flow balance index, and performing adaptive correction of the branch hydraulics based on the changes in the flow of each branch.

[0057] The fifth layer is for hydraulic balance evaluation and adaptive correction. The control module defines the branch flow balance index: , when to When, it can be assumed that each branch meets the hydraulic balance requirements; when When the limits are continuously exceeded, the controller determines the cause based on the branch pressure difference, valve position, and flow residual: if the valve is close to fully open and the flow is insufficient, the branch pressure difference is insufficient or blocked; if the valve is close to closed and the flow is still too high, the valve is leaking or the bypass is short-circuited; if the inlet flow and outlet flow differ greatly, the leak is leaking, the air blockage is blocked, or the sensor is abnormal.

[0058] To reduce multi-branch coupling, the control module can also establish a small-signal sensitivity matrix: , in, This represents the flow change vector for each branch. Let the branch valve opening change vector be... This refers to the change in main pump speed. The controller calculates this based on the measured step response or a model. , The coordinated correction of each valve and main pump is solved by least squares or quadratic programming to minimize the flow error of each branch and the valve pressure drop loss.

[0059] During startup, the system first opens the main bypass or end bypass to circulate and exhaust gas using the main pump at low speed and detect leaks. Then, it gradually opens the valves of each branch to bring the flow rate to the minimum liquid retention value. Once the pressure, temperature, and SoC conditions are met, the target flow rate of each branch is increased according to the electrical power command. During shutdown, the fuel cell stack current is first reduced, then the branch flow rate is reduced to the flushing or liquid retention flow rate, and finally the corresponding isolation valves are closed.

[0060] As a preferred embodiment, the method further includes adding a local liquid storage buffer tank for stack nodes where there are charge state disturbances.

[0061] In a shared storage tank architecture, user nodes may be in different charging and discharging states, which may cause branch SoC disturbances in a short period of time. This invention addresses this problem by using centralized storage tank SoC monitoring, critical branch bypass SoC detection, local buffer tanks, and scheduling constraints.

[0062] Online SoC monitoring modules are installed at the outlet and inlet of the centralized positive and negative electrode storage tanks. The outlet SoC indicates the state of the shared electrolyte entering each stack, while the inlet SoC determines the impact of electrolyte return at each node on the overall state of the tank. The control module integrates the tank SoC estimate, the coulomb integral of the current at each node, and the open-circuit voltage results of the critical branches. , in, The weights are adaptively adjusted based on the sensor's health status and operating conditions.

[0063] For critical nodes where charging and discharging power changes rapidly, are far from centralized liquid storage areas, or have high requirements for power supply continuity, small local buffer tanks can be installed at branch inlets or near the fuel cell stack. The effective volume of the local buffer tank... Can be based on the node's rated flow rate and buffer time Sure: , in, The timeframe can be selected from 30s to 300s depending on the application scenario, or based on short-term power smoothing requirements from 1min to 10min. The buffer tank does not replace the centralized storage tank, but rather reduces the impact of main pipeline pressure fluctuations, SoC disturbances, and main pump response delays on the local fuel cell stack on a short timescale.

[0064] The SoC in a local buffer can be described using a fully hybrid model: , in, Indicates the charging or discharging direction. The control module determines this based on... and The deviation determines whether to enter the balancing mode. When the deviation exceeds the threshold, one or a combination of the following actions can be performed: increase the circulation flow of the branch, reduce the power of the node, start the buffer tank bypass circulation, adjust the charging and discharging plan of other nodes, or arrange for the electrolyte balancing circulation of the whole system during low load periods.

[0065] As a preferred embodiment, it also includes: electrical power scheduling and fluid flow control for each stack node at multiple time scales.

[0066] As a preferred embodiment, electrical power scheduling and hydraulic flow control are performed on each fuel cell stack node at multiple time scales, including: at the day-ahead optimization layer, adjusting the charging and discharging power plans of each fuel cell stack node according to the output of new energy sources, load, electricity price, and user demand; at the intraday rolling layer, rolling corrections are made to the charging and discharging power plans based on measured power data; at the real-time power and hydraulic control layer, real-time power tracking, target pressure and flow calculation, pressure envelope calculation, main pump frequency conversion control, and branch valve closed-loop control are performed based on the charging and discharging power plans corrected by the intraday rolling layer.

[0067] Considering the time-varying characteristics of distributed terminal loads, renewable energy output, electricity prices, user demand, and electrolyte SoC (System-on-Chips), it is difficult to simultaneously consider day-ahead planning, intraday rolling correction, real-time power response, flow tracking, and pump consumption optimization from the perspective of local control of a single fuel cell stack. This invention coordinates the charging and discharging power, SoC, pump speed, and valve opening of each node across multiple time scales: day-ahead, intraday, and real-time. Under conditions of varying node distances, elevations, and dynamic loads, it achieves cross-node hydraulic balance and independent flow regulation, and isolates faulty nodes without affecting the operation of other nodes in the event of a fault.

[0068] This invention unifies electrical power scheduling and hydraulic flow control within a multi-timescale operating framework. This framework includes at least a day-ahead optimization layer, an intraday rolling layer, a real-time power and hydraulic control layer, and a safety interlocking layer. Each layer has different control objectives and execution frequencies, but they are interconnected through a chain relationship of power targets, current targets, flow targets, and pump speed / valve position targets.

[0069] The current optimization layer uses time steps of 15 minutes, 30 minutes, or 1 hour to optimize the charging and discharging power plans for each fuel cell stack node, taking into account next day's load forecast, renewable energy output forecast, electricity price, user demand, centralized storage tank SoC, and equipment availability. The following objective function can be used: , in, This indicates the cost of purchasing and selling electricity or peak shaving and valley filling. To predict pump consumption, the squared term is used to limit frequent power fluctuations. This is used to prevent the SoC from approaching its upper and lower limits. Used to constrain the backup power capacity or power requirements that the user side must meet.

[0070] The current optimization needs to meet the following constraints: , The intraday rolling layer, with a cycle of 5 to 15 minutes, continuously adjusts the day-ahead plan based on measured load, renewable energy deviations, temporary user demands, and equipment status. The intraday layer can employ model predictive control to continuously optimize nodal power for the next 1 to 4 hours. And will update Send it to the real-time control layer.

[0071] The real-time power and hydraulic control layer performs power point tracking, target flow calculation, pressure envelope calculation, main pump frequency conversion control, and branch valve closed-loop control with a cycle of 0.1s to 5s. The real-time layer does not re-solve long-cycle economic optimization problems, but rather ensures that the node power plan issued by the intraday layer is safely achieved within the constraints of stack voltage, current, SoC, temperature, and hydraulics.

[0072] As a preferred embodiment, it also includes: performing safety interlock control in the event of anomalies in the status data of the fuel cell node.

[0073] The safety interlock layer is independent of the economic optimization objective and has the highest priority. When low liquid level, overpressure, leakage, insufficient flow, pump failure, valve jamming, electrical insulation failure, SoC exceeding limit or temperature exceeding limit occurs, the safety layer can directly perform actions such as flow restriction, pump speed reduction, bypass opening, branch valve closure, reactor shutdown or isolation of the faulty node.

[0074] The specific execution process of the above multi-timescale collaborative scheduling is as follows: The control module first determines each node at the day-ahead layer. The intraday layer is obtained based on the latest forecast. The real-time layer will Convert to and ; Hydraulic controller according to calculate and The local node controller completes the traffic loop and reports the execution results; the control module corrects the subsequent time period plan based on the execution deviation.

[0075] Typical inputs and outputs for each control level are as follows: The day-ahead optimization layer uses a time step of 15 minutes to 1 hour, inputting load forecast, renewable energy forecast, electricity price, user demand, SoC upper and lower limits, and equipment availability, and outputting charging and discharging power plans for each node, shared capacity allocation, and estimated pump consumption; The intraday rolling layer uses a period of 5 minutes to 15 minutes, inputting measured load, forecast deviation, node availability status, and online SoC estimation, and outputting corrected node power targets, operational reserves, and balancing strategies; The real-time control layer uses a period of 0.1 seconds to 5 seconds, inputting node flow rate, pressure, temperature, current, voltage, valve position, and pump speed, and outputting branch target flow rate, valve opening, and main pump speed or differential pressure setting; The safety interlock layer is triggered by events at the millisecond to second level, inputting overpressure, leakage, blockage, low liquid level, high temperature, sensor fault, and electrical fault signals, and outputting current limiting, bypass, valve closure, pump stop, fault node isolation, and alarm actions.

[0076] The present invention has the following beneficial effects: (1) Significantly reduces initial system investment and maintenance costs. Traditional A standalone flow battery energy storage module typically requires A positive and negative electrode liquid storage tank and Set or A circulating pump; this invention can be used with one or a few sets of centralized positive and negative electrode storage tanks. The use of distributed fuel cell stacks reduces the duplication of configuration of storage tanks, pump sets, heat exchangers, dikes and maintenance access, and facilitates centralized replenishment, testing and life management.

[0077] (2) Saves installation space and is suitable for dense scenarios. The user side mainly arranges fuel cell stacks, branch detection boxes and power conversion equipment, without the need for large liquid storage tanks, which can significantly reduce the footprint, load-bearing and corrosion protection requirements of the node side. This structure is particularly suitable for data centers, industrial parks, commercial complexes, underground spaces of buildings, microgrids and integrated source-grid-load-storage scenarios.

[0078] (3) Improve electrolyte utilization and support capacity sharing. Multiple users share the same electrolyte storage tank, breaking down the capacity barriers of a single user and a single stack. The control module can dynamically allocate energy storage capacity according to the global SoC and user priority, realizing energy sharing and emergency support among multiple nodes.

[0079] (4) Improve the stability of hydraulic distribution. By detecting inlet / outlet pressure and flow, independent closed-loop control of branch valves and pressure envelope control of main pump, the target flow can be tracked even when the branch length, elevation, fuel cell flow resistance and power requirements are different, thus avoiding overflow at the near end and underflow at the far end.

[0080] (5) Reduce pump consumption under non-rated operating conditions. The present invention calculates the target flow rate in real time based on the fuel cell current and sets the main pump to the pressure difference required by the most unfavorable branch, thereby avoiding the main pump from operating at the rated maximum head for a long time; at the same time, it reduces unnecessary valve throttling losses, thereby improving the overall efficiency of the system.

[0081] (6) Enhance system regulation flexibility and facilitate the consumption of new energy. The system supports day-ahead, intraday and real-time multi-timescale coordinated scheduling, and can adjust the charging and discharging plans of each node and the total power consumption curve according to wind and solar power output, load, electricity price and user demand, which helps to improve the local consumption level of renewable energy.

[0082] (7) The technical solution evolves smoothly and has strong operability. This invention does not require changes to the core electrochemical structure of the flow battery. It can be achieved on the basis of existing flow battery stack and storage tank technologies through centralized liquid storage, pipeline reconstruction, node detection boxes and control system upgrades, providing an implementable technical path for the evolution of traditional flow batteries to shared, gridded and distributed energy storage.

[0083] The distributed energy storage system of flow battery provided by the present invention is described below. The distributed energy storage system of flow battery described below and the distributed energy storage method of flow battery described above can be referred to and correspond to each other.

[0084] Please refer to Figure 2 , Figure 2 This is a schematic diagram of a distributed energy storage system for flow batteries provided by the present invention.

[0085] This invention also provides a flow battery distributed energy storage system, which operates the aforementioned flow battery distributed energy storage method. The system includes: a centralized electrolyte storage module for centralized storage of electrolyte and provision of shared capacity; the centralized electrolyte storage module includes a centralized positive electrolyte storage tank and a negative electrolyte storage tank; a shared supply and return liquid network module for connecting each distributed stack node in parallel to the centralized electrolyte storage module so that all stack nodes share the electrolyte; a main pump module for providing electrolyte circulation driving force to the shared supply and return liquid network module; a distributed stack node module for realizing charge and discharge power output or absorption at each user side; the distributed stack node module includes multiple distributed stack nodes; and a control module for performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0086] This invention provides a globally shared architecture for a centralized liquid storage-distributed battery stack, including one or more centrally deployed positive electrolyte storage tanks and negative electrolyte storage tanks, a variable frequency main liquid supply pump, a liquid supply main pipe, a liquid return main pipe, and multiple distributed flow battery stacks connected to the centralized liquid storage tanks via a parallel pipeline network.

[0087] This invention adopts a shared pipeline network structure with four main pipes and multiple branches connected in parallel. Each fuel cell stack node is connected to the corresponding main pipe through a positive electrode liquid supply branch, a positive electrode liquid return branch, a negative electrode liquid supply branch, and a negative electrode liquid return branch, forming a pipeline network topology in which the positive and negative electrodes circulate independently and the node side shares centralized liquid storage.

[0088] In terms of node detection and regulation, each distributed fuel cell stack node is equipped with pressure, flow, temperature, SoC or electrolyte status detection, valve position feedback, electrical quantity acquisition and local controller, making each fuel cell stack node a measurable, adjustable and isolated hydraulic control node.

[0089] In terms of cross-node hydraulic balance and independent flow regulation, relying on the flow regulating valves, pressure sensors and flow sensor feedback set at the inlet / outlet of each fuel cell stack, the control module coordinates and regulates the opening of valves in each branch and the frequency conversion pump in the main pipeline to achieve independent tracking of target flow at nodes with different distances, elevations and power requirements.

[0090] In terms of pump consumption optimization based on minimum pressure envelope, the required pressure difference for the most unfavorable branch is calculated according to the target flow rate of each branch, the hydraulic model of the pipeline network and the pressure drop of the fuel cell stack. The main pump is set to the minimum pressure envelope that meets the flow requirements of all nodes, and the pump consumption under non-rated conditions is reduced by using a variable frequency pump.

[0091] In terms of coupling electrochemical flow demand with hydraulic control, the target flow rate of the branch is calculated based on the node power, stack voltage, current, number of series single cells, active material concentration and allowable single-pass SoC change, and then the flow closed loop is realized by the branch valves and the main pump.

[0092] In terms of online identification of hydraulic parameters of multiple branches, the equivalent resistance of branches, the flow resistance of fuel cell stack and the flow capacity of valves are estimated online by using node pressure, flow rate, valve position and temperature data, and used to adaptively correct valve opening feedforward and main pump differential pressure setting.

[0093] In terms of coordinated operation across multiple time scales, the charging and discharging plans of multiple fuel cells, the opening degree of valves in each branch, and the speed of the main pump are comprehensively optimized by combining new energy forecasts, load demand, electricity price, storage tank SoC, fuel cell stack operation constraints, and pipeline hydraulic constraints at the levels of day-ahead planning, intraday rolling, and real-time control.

[0094] In terms of local buffering and centralized monitoring for cross-user SoC differences, online SoC monitoring modules are set up at the inlet and outlet of centralized storage tanks and key branches, and small buffer tanks or local liquid storage volumes are configured on specific fuel cell stack branches to provide short-term power buffering and SoC disturbance isolation.

[0095] In terms of fluid dynamics design and equivalent calculation of the hydraulic characteristics of the pipeline network, the calculations are carried out considering the frictional losses along the main pipeline and branch lines, elevation differences, valve pressure drops, filter pressure drops and equivalent flow resistance of the fuel cell stack, as well as the calculations for pipe diameter configuration, pump head selection, valve selection and pump consumption optimization.

[0096] Figure 3 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 3 As shown, the electronic device may include a processor 301, a communications interface 302, a memory 303, and a communication bus 304. The processor 301, communications interface 302, and memory 303 communicate with each other via the communication bus 304. The processor 301 can call logical instructions in the memory 303 to execute a distributed energy storage method for flow batteries. This method includes: connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank via a parallel pipeline network, so that all stack nodes share the electrolyte; and performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0097] Furthermore, the logical instructions in the aforementioned memory 303 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute a distributed energy storage method for flow batteries provided by the above methods. The method includes: connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank through a parallel pipeline network, so that all stack nodes share the electrolyte; and performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0099] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a distributed energy storage method for flow batteries provided by the methods described above. The method includes: connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank respectively through a parallel pipeline network, so that all stack nodes share the electrolyte; and performing cross-node hydraulic control based on the status data and power requirements of each stack node.

[0100] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0101] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A distributed energy storage method using flow batteries, characterized in that, include: Multiple distributed flow battery stack nodes are connected to a centralized positive electrolyte storage tank and a negative electrolyte storage tank through a parallel pipeline network, so that all stack nodes can share the electrolyte. Cross-node hydraulic control is performed based on the status data and power requirements of each fuel cell stack node.

2. The distributed energy storage method for flow batteries according to claim 1, characterized in that, The step of connecting multiple distributed flow battery stack nodes to a centralized positive electrolyte storage tank and a negative electrolyte storage tank via a parallel pipeline network includes: Each fuel cell node is connected to the positive electrolyte supply main pipe and the positive electrolyte return main pipe through a positive electrolyte supply branch and a positive electrolyte return branch, and is connected to the negative electrolyte supply main pipe and the negative electrolyte return main pipe through a negative electrolyte supply branch and a negative electrolyte return branch. The positive electrolyte supply main pipe and the negative electrolyte supply main pipe are respectively connected to the positive electrolyte storage tank and the negative electrolyte storage tank.

3. The distributed energy storage method for flow batteries according to claim 1, characterized in that, The cross-node hydraulic control based on the status data and power requirements of each fuel cell node includes: Based on the status data and power requirements of each fuel cell stack node, the target pressure flow rate of the corresponding branch of each fuel cell stack node is calculated; Based on the target pressure and flow rate of each branch, the hydraulic model of the pipeline network, and the pressure drop of the fuel cell stack, the minimum pressure envelope of the main pump is calculated, and the main pump is controlled to provide the minimum total pressure difference required for the first type of branch; the minimum pressure envelope satisfies the pressure and flow rate requirements of all nodes. Based on the measured pressure and flow rate and the target pressure and flow rate of the fuel cell node, control the branch valves of the second type of branch; the pressure difference required for the second type of branch is less than the pressure difference required for the first type of branch.

4. The distributed energy storage method for flow batteries according to claim 1, characterized in that, Also includes: Based on the flow deviation between the positive and negative electrodes, the flow balance control between the positive and negative electrodes is performed.

5. The distributed energy storage method for flow batteries according to claim 1, characterized in that, Also includes: The hydraulic balance of the branches is evaluated using the branch flow balance index, and the hydraulic balance of the branches is adaptively corrected according to the changes in the flow of each branch.

6. The distributed energy storage method for flow batteries according to claim 1, characterized in that, Also includes: For fuel cell stack nodes with charge state disturbances, add local liquid storage buffer tanks.

7. The distributed energy storage method for flow batteries according to any one of claims 1 to 6, characterized in that, Also includes: Electrical power scheduling and fluid flow control are performed on each fuel cell stack node at multiple time scales.

8. The distributed energy storage method for flow batteries according to claim 7, characterized in that, The electrical power scheduling and fluid flow control of each fuel cell stack node at multiple time scales includes: In the current optimization layer, the charging and discharging power plans of each fuel cell stack node are adjusted according to the output of new energy sources, load, electricity price and user demand. In the intraday rolling layer, the charge and discharge power plan is rolled over and corrected based on the measured power data; In the real-time power and hydraulic control layer, based on the charge and discharge power plan corrected by the intraday rolling layer, real-time power tracking, target pressure and flow calculation, pressure envelope calculation, main pump frequency conversion control, and branch valve closed-loop are executed.

9. The distributed energy storage method for flow batteries according to claim 1, characterized in that, Also includes: Safety interlock control is implemented when there are abnormalities in the status data of the fuel cell node.

10. A flow battery distributed energy storage system, characterized in that, The system operates the distributed energy storage method for flow batteries according to any one of claims 1 to 9; the system comprises: A centralized electrolyte storage module is used to centrally store electrolyte and provide shared capacity; the centralized electrolyte storage module includes a centralized positive electrode electrolyte storage tank and a centralized negative electrode electrolyte storage tank; A shared supply and return liquid pipeline module is used to connect each distributed fuel cell stack node in parallel to the centralized liquid storage module, so that all fuel cell stack nodes can share the electrolyte. The main pump module is used to provide electrolyte circulation driving force to the shared supply and return liquid network module; A distributed fuel cell node module is used to realize charging and discharging power output or absorption at each user side; the distributed fuel cell node module includes multiple distributed fuel cell nodes; The control module is used to perform cross-node hydraulic control based on the status data and power requirements of each fuel cell stack node.

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