CN111969693A - Multi-agent lithium battery cluster energy storage system - Google Patents
Multi-agent lithium battery cluster energy storage system Download PDFInfo
- Publication number
- CN111969693A CN111969693A CN202010883210.5A CN202010883210A CN111969693A CN 111969693 A CN111969693 A CN 111969693A CN 202010883210 A CN202010883210 A CN 202010883210A CN 111969693 A CN111969693 A CN 111969693A
- Authority
- CN
- China
- Prior art keywords
- lithium battery
- energy storage
- charge
- battery energy
- formula
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/00032—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries characterised by data exchange
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention provides a multi-agent lithium battery cluster energy storage system, which establishes a mathematical model through rated capacity, actual capacity and output/input characteristics of different types of lithium batteries; the single lithium battery energy storage units in the cluster system are provided with communication modules and analysis modules, can realize communication with each other and have certain functions of data processing, analysis, instruction receiving and sending. The lithium battery cluster energy storage system adopts a double-loop control mode, the inner loop is a self-adjusting loop based on a single module, and self-feedback is carried out according to parameters such as the charge state, the temperature and the like of the self-adjusting loop, so that power adjustment is realized. The outer ring is a system adjusting ring, batteries which most meet the operation requirements in the similar batteries are set as a host through mutual communication among the lithium batteries, and based on the consistency principle, the rest lithium battery packs in the control system are self-regulated, so that the energy storage or energy release power and the charging and discharging margin ratio are approximately consistent. On the premise of ensuring safety, the stable and efficient operation of the energy storage system is realized.
Description
Technical Field
The invention relates to the technical field of energy storage, in particular to a multi-agent lithium battery cluster energy storage system.
Background
With the large access of renewable energy sources represented by wind and light in the future, the randomness, intermittence and fluctuation of the output of the renewable energy sources cause the uncertainty of the renewable energy sources in the unit time faced by the power system to be increased. Meanwhile, in recent years, the economy has steadily increased, and the electricity consumption has also been on the rise year by year. The safety, stability, reliability and economy of the power grid are seriously harmed by abnormal operation of the power grid caused by unbalanced supply and demand.
In order to solve the problems, the rapid development of the energy storage technology is an inevitable choice for the development of the future power industry, and the lithium battery not only has the characteristic of high energy density, but also has the advantages of high charging and discharging speed, mature application scheme and lower cost along with the development of the technology. However, the following problems mainly face large-scale cluster utilization aiming at the energy storage technology at present:
1. the lithium battery belongs to electrochemical energy storage, wherein chemical substances can be attenuated in different degrees after being subjected to energy conversion for a plurality of times, and when the traditional large-scale cluster utilization is carried out, because all batteries execute the same single command, the service life of part of batteries can be obviously reduced, and meanwhile, the energy storage effect of part of batteries with excellent performance can not be exerted to the maximum extent, so that the overall working efficiency of the system is influenced.
2. The traditional lithium battery cluster energy storage system control mode is master-slave control, but the storage battery has a certain degree of physique difference, in the using process, the working performance of the storage battery can be changed when the capacity is attenuated to different degrees, the slave machines with excellent performance can be influenced by the host to a great extent, meanwhile, the traditional centralized control analyzes signals and obtains the running state of a single lithium battery energy storage module, the running state is calculated one by one to issue instructions, certain delay can be caused, reaction delay exists in application scenes with large variation amplitude and speed, such as photovoltaic wind power, and the like, and the regulation performance of the traditional centralized control system is not facilitated.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and strive to improve the intelligence and the modularization degree of a large-scale lithium battery cluster energy storage system. The difference and the change of the chemical property and the working characteristic of the lithium battery can be fully considered, the master-slave position is flexibly changed, the service life of the battery is prolonged as far as possible on the premise that the adjustment performance of the system is ensured to the greatest extent, and the economical efficiency and the environmental protection performance of the system are effectively improved.
In order to achieve the purpose, the invention provides a multi-agent lithium battery cluster energy storage system, which establishes a mathematical model through rated capacity, actual capacity and output/input characteristics of different types of lithium batteries, and meanwhile, single lithium battery energy storage units in the cluster system are provided with a communication module and an analysis module, can realize communication with each other, have certain data processing, analysis and instruction receiving and sending functions, are constructed into a single lithium battery energy storage agent, and are constructed into a multi-agent system through cluster combination.
And then, a double-loop control mode is established, the inner loop is a self-adjusting loop based on a single lithium battery, self feedback is carried out according to parameters such as the charge state, the temperature and the like of the self-adjusting loop, and then power adjustment is realized, so that the module per se achieves the best effect according to the actual working condition of the self-adjusting loop. The outer ring is a system adjusting ring, the batteries which best meet the operation requirements in the similar batteries are set as a host through mutual communication among the multiple lithium batteries, based on the principle of a consistency algorithm, the other lithium battery packs in the system are controlled to perform self adjustment, the ratio of the energy storage or energy release power to the charge-discharge margin is enabled to be approximately consistent, a weighted sliding filtering algorithm is added, the actual output power of an adjustment object of the energy storage system is subjected to smoothing processing, and a final control instruction is formed for each lithium battery energy storage module.
The invention provides a multi-agent lithium battery cluster energy storage system, which specifically comprises:
in a single lithium battery self-feedback control link, the charge state value of a lithium battery is used as a control quantity, and through a droop control mode in inner loop current of the lithium battery, each lithium battery energy storage unit can adjust a droop coefficient according to the charge state, so that the power of the lithium battery energy storage unit is dynamically controlled, more difference power is output when the output power is insufficient when the charge state is high, and less redundant power is absorbed when the power is residual; the lithium battery energy storage unit with a low state of charge absorbs more power when the power is surplus, and the system outputs less difference power when the output power is insufficient, so that the balance control of the state of charge of the lithium battery is realized.
Firstly, the charge capacity of all lithium batteries in the system is calculated, and the remaining capacity can be calculated according to the SOC, wherein the formula is as follows:
in the formula, S0The initial state of charge value of the lithium battery; eta is the coulomb efficiency of charging and discharging of the lithium battery in operation; i isCAnd IFCurrent value for charging and discharging lithium battery (I for discharging)FNegative) with corresponding charging and discharging time t1And t2；C1The self-loss discharge capacity of the lithium battery; and C is the initial capacity of the lithium battery.
Then, the SOC values of the N lithium battery energy storage units are calculated according to the formula1、SOC2、……、SOCNIn order to ensure the safe operation of the lithium battery, the state of charge value of the lithium battery is specified to be 20-80%, and the state of charge difference coefficient alpha of each energy storage unit is definediComprises the following steps:
obtaining alpha by the above formulaiUsed for determining the power regulation of the lithium battery and then according to the power P of the lithium batterybatAdjusting the state of charge difference coefficient of the lithium battery, wherein an adjustment formula is obtained by calculating according to the following formula:
in the above formula, rbatiDenotes the ith rbatNamely the charge state difference value of the ith lithium battery energy storage system.
At the moment, the SOC values of the N lithium battery energy storage units are calculated according to the SOC values calculated before1、SOC2、……、SOCNThe SOC can be obtained by the following formulaaveI.e. the average state of charge value of the lithium battery pack:
according to the adjusted difference coefficient, the droop coefficient of each lithium battery energy storage unit is obtained as follows:
wherein beta is the initial droop coefficient, SOCaveThe average state of charge value of the lithium battery pack is obtained, so that the reference current value of the internal current loop in the feedback loop of each lithium battery energy storage unit can be obtained according to the average state of charge value:
Irefi＝ΔI-Ibatiμxbati
wherein, Delta I is the current value in the external current loop in the feedback loop of the lithium battery energy storage unit, IbatiFor the output current of the I-th group of lithium battery energy storage units, IbatiμxbatiFor the current correction of the lithium battery, through the control mode, the lithium battery with a high SOC value generates more electric energy in the operation process, and the lithium battery with a low SOC value absorbs more electric energy, so that the capacity difference of each lithium battery energy storage unit is dynamically reduced, and the state of charge of the battery in the operation process is ensured to be consistent as much as possible.
Droop control is adopted in power balance control, and the method comprises the steps of adding a control loop simulating motor characteristics into the droop control loop, detecting and controlling each battery energy storage unit through droop coefficients, and adjusting output frequency and voltage amplitude, so that current equalization is realized, effective power distribution is realized, and the overall efficiency of the system and the utilization degree of all lithium battery energy storage units are improved.
The droop control causes the bus voltage to drop when the power is insufficient, and further the reference current value I of the current inner ring needs to be designed according to the charge state of the lithium batteryrefi(s), can be represented by the following formula:
in the above formula, UrefIs a reference voltage, i.e. the normal bus voltage when no regulation is required, UDCThe bus voltage is real-time, and the bus voltage are compared through the magnitude of the bus voltage and the bus voltageAnd controlling the lithium battery energy storage system to enter a charge and discharge mode or keeping a standby mode. k is a radical ofpAnd kiRespectively as a proportional coefficient and an integral coefficient in the voltage and current double closed loop PI regulation,
forming a typical proportional-integral PI regulator, s is a transfer function of a controlled object and is determined by a specific waiting quantity of a system, UbatiAnd outputting the voltage of the ith lithium battery energy storage unit in real time.
The robustness and the stability of the lithium battery energy storage system need to be improved, so that the reference current value I is obtainedrefiAnd(s) introducing a direct current motor characteristic function in the calculation, and adding certain inertia to the lithium battery energy storage system, so that frequent impact on the energy storage system caused by external disturbance can be prevented, and fluctuation is restrained. Firstly, establishing a mathematical model of the direct current motor, which is represented by the following formula:
mathematic model formula of upper direct current motor, CTAnd phi is torque coefficient and magnetic flux respectively, and can be taken as 5.1, T by referring to the general value of the actual direct current motoreElectromagnetic torque, T, generated for the electric machinemMechanical torques, ω and ω, input to the motor0The actual mechanical angular velocity and the rated value of the DC motor, D the damping coefficient of the motor, g the inertia coefficient, in kg.m2P is the electromagnetic power of the motor, and R is the equivalent internal resistance of the motor. And (3) carrying out the following calculation by using a mathematical model formula of the upper direct current motor:
the electromagnetic power P and the angular speed are in a relation of:
the deviation relationship between power P and ω can be derived from the above equation:
electromagnetic torque TeThe deviation relationship with the angular velocity ω is:
obtaining a transfer function G(s) of the control loop of the analog motor as follows:
through the addition of the link, a delay effect is added for the output of the lithium battery energy storage unit, and the effect is equal to a first-order inertia control loop. The abnormal fluctuation of system adjustment caused by the occurrence of the unplanned small interference can be effectively prevented. I isrefiIs the reference current value mu of the inner current loop in the feedback loop of the ith lithium battery energy storage unitxbatiAnd the droop coefficient of the ith lithium battery energy storage unit is shown. Therefore, double-loop control of the state of charge and the power balance adopted by imitating the running characteristics of the motor is realized, when the motor works normally, the outer adjusting ring is preferred, when the state of charge is abnormal, the inner adjusting ring is preferred, and current sharing is realized as far as possible through droop control, so that the universality and the effectiveness of a current adjusting command are ensured.
A consistency algorithm in the algorithms is used as an outer ring part in double-ring control, can be adjusted aiming at each intelligent lithium battery energy storage unit in a multi-intelligent lithium battery cluster energy storage system, and comprises the following steps:
the consistency algorithm is generated based on graph theory, and information transmission among a plurality of lithium battery energy storage units can be represented by a relational graph. G ═ V, E, denotes a graph, where V denotes a set of non-empty vertices,
representing the set of edges formed by node pairs, if the information exchange can be carried out between the ith node and each jth node, the node pair is called to have a connecting edge, if each edge in the graph G has a direction, the graph G is called as a directed graph, otherwise, the graph G is called as an undirected graph. Let G have an adjacency matrix A with aijFor the ith row and jth column element in the A matrix, when the node i can directly receive the information of the node j, aijAnd if the weight is greater than 0, the connection weight of the nodes i and j is less than zero, and if the weight is not received, the two nodes are not interconnected and are directly equal to zero. For an undirected graph, taking A as a symmetric array, a is when i ═ j or i and j are not interconnectedij0; a when i ≠ j ij1. In the graph theory, the number of edges pointing to a certain node is the in-degree of the node, the leaving is the out-degree, a matrix D is defined as an in-degree matrix, D is a diagonal matrix, and elements in D are expressed by the following formula:
for an undirected graph, the node in-degree and out-degree numbers are equal, and D is a degree matrix at the moment. The relationship between nodes and edges in the graph can be expressed by the laplace equation, where L ═ D-a, the following equation can be used:
D＝[dij]is a row random matrix defined by:
when the lithium battery is charged and discharged, the following iteration factors and discharge modes can be obtained as initial values according to the working state of the lithium battery at the moment when the lithium battery receives the regulating instruction:
and (3) charging mode:
wherein
For the ith lithium battery energy storage unit, the larger the SOC value is, the larger the discharge margin of the lithium battery energy storage unit with higher charge state is, the larger the initial discharge proportion is,
the lower the SOC value is, the larger the charging margin of the lithium battery unit with the lower state of charge is, and the larger the initial charging proportion is, for the current charging margin of the ith lithium battery energy storage unit.
Calculating the iteration factors by an iteration formula in a consistency algorithm, wherein the iteration formula is as follows:
wherein Δ pdiffProviding an ideal reference direction for the difference between the scheduling command and the sum of the charge and discharge power of each lithium battery energy storage unit and the iteration of the consistency algorithm, wherein p is the ideal adjustment power of the 'host' in the unit time in the adjustment process, and p is the ideal adjustment power of the 'host' in the adjustment processiThe power is adjusted for the actual power of all "slaves" in that unit of time. dijThe meaning of the method is that the relation between the in-degree and the out-degree of any two lithium battery energy storage units of the multi-agent chemical lithium battery energy storage units is expressed, the lithium battery energy storage units in the system can be in two-to-two communication, and the real-time master-slave relation under the dynamic master-slave change can be displayed. The convergence rate can be controlled by adjusting the convergence coefficient, and if the coefficient is too small, the convergence rate is slow, and if the coefficient is too large, the command calculation result cannot be converged to an ideal range. The iteration direction is corrected through the deviation of each iteration result of the iteration formula and the target adjustment amount, so that distributed optimization and closeness are performed on each lithium battery energy storage unit according to the 'ideal host' at most each moment, and effective adjustment of the electric energy parameters of the adjustment object is realized.
In the multi-agent lithium battery cluster energy storage system, all the lithium battery energy storage units are constructed to realize mutual communication, and the intelligent agent units with data analysis and processing, command receiving and sending and mutual coordination control can be realized, a double-loop control mode is established, the lithium battery energy storage cluster system can realize multi-agent mode operation by self-feedback adjustment of a single lithium battery energy storage module in an inner loop and overall adjustment of the system in an outer loop based on a consistency principle, the master-slave relation can be flexibly adjusted according to parameters such as the charge state, the working performance and the like of a lithium battery on the premise of ensuring the working performance of the energy storage system, the coordination operation among the lithium battery energy storage units can be realized, the lithium battery energy storage units can be flexibly increased and decreased according to needs at the later stage, and the modularization degree of the system and the adjustment rate and stability are effectively improved, the disaster tolerance capability of the system is enhanced, and meanwhile, the service life of the lithium battery is prolonged to the greatest extent by adopting the energy and power balance algorithm based on the charge state, the working efficiency and the economical efficiency of the system are improved, and the integral environmental protection degree of the system is also improved.
Drawings
Fig. 1 is an operation topological diagram of a multi-agent lithium battery cluster energy storage system.
Fig. 2 is a multi-agent topology structure diagram formed by lithium battery units in the lithium battery energy storage cluster system according to the invention.
Fig. 3 is an explanatory view of an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly apparent, the present invention is further described in detail with reference to the drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention provides a novel multi-agent lithium battery cluster energy storage mode, wherein all lithium battery energy storage units in the system are provided with a communication and calculation control device, the traditional central unified control or absolute master-slave control is cancelled, and the intelligent lithium battery energy storage units are constructed, so that a multi-agent system is established, and the effective control of the electric energy parameters of an object to be adjusted is realized effectively, quickly and stably.
In practice, as illustrated in fig. 3, the system of this embodiment is composed of three parts, namely, a power supply terminal, a load terminal and an energy storage terminal. The energy storage end comprises three lithium battery energy storage units to form an energy storage system, the three lithium battery energy storage units are in three groups, and each group of batteries are connected with each other through a communication system, can send, transmit and receive control signals and have a certain data analysis function.
The method comprises the following steps: the system monitors three parts of power in real time, the power of the energy storage system is defined as the difference value between a load end and a power supply end, when the difference value is positive, the energy storage system sends out power, when the difference value is negative, the energy storage system absorbs power, and when the difference value is zero, the energy storage system enters a standby state.
Step two: when the energy storage system receives the adjustment requirement as required, after the three lithium battery energy storage units receive the difference value of the compensation quantity, the actual state of charge (SOC) of the three lithium battery energy storage units is firstly calculated respectively, and the SOC can be calculated through the following formula:
in the formula, S0The initial state of charge value of the lithium battery; eta is the coulomb efficiency of charging and discharging of the lithium battery in operation; i iscAnd IFCurrent value for charging and discharging lithium battery (I for discharging)FNegative) with corresponding charging and discharging time t1And t2；C1The self-loss discharge capacity of the lithium battery; and C is the initial capacity of the lithium battery.
Step three: according to the SOC obtained by the calculation of the last step1、SOC2、SOC3And judging whether the three groups of batteries are in the range of 20% -80% of the capacity values of the three groups of batteries, if not, the unit exits the adjusting process, and continues to charge and discharge. Assuming that the three groups of batteries are all in the specified SOC range, the next operation is carried out, and the state of charge difference coefficient alpha of each energy storage unit is definediComprises the following steps:
according to the formula, the specific adjusting power coefficients of the three groups of battery packs are determined, namely the output weight of each battery in the adjusting process and the adjusting power of the lithium battery, the more the initial electric quantity of the storage battery is, the larger the charge state value and the average value of the three groups of batteries are, and the corresponding alpha isiAnd if so, correcting according to the value of the actually required output power of the battery, wherein the correction process can be represented by the following formula:
in the formula, rbatiIs a coefficient of difference, PbatThe power is actually required for the battery.
Step four: obtaining a difference coefficient r after correctionbatiThe circuit comprises three groups of batteries, wherein the three groups of batteries are connected in series, and the three groups of batteries are connected in series and are connected in series. The sag factor of a single lithium battery is defined as:
wherein beta is the initial droop coefficient, SOCaveThe average state of charge value of the lithium battery pack is obtained, so that the reference current value of the inner current outer ring in the feedback loop of the single lithium battery energy storage unit can be obtained according to the average state of charge value:
Irefi＝ΔI-Ibatiμxbati
step five: because three groups of batteries adopt a droop control mode to perform power balance, the droop control can cause the voltage of a bus to drop when the power is insufficient, and then the reference current value of the current inner ring needs to be designed aiming at the charge state of the lithium battery, and can be represented by the following formula:
therefore, double-loop control of the state of charge and the power balance adopted by imitating the running characteristics of the motor is realized, when the motor works normally, the outer adjusting ring is preferred, when the state of charge is abnormal, the inner adjusting ring is preferred, and current sharing is realized as far as possible through droop control, so that the universality and the effectiveness of a current adjusting command are ensured.
Step six: the control mode of the battery unit is obtained through the steps, and a consistency adjustment mode is involved at the moment; if three groups of batteries contained in the energy storage system are respectively marked as A, B and C, according to specific energy storage regulation requirements, assuming that the effect of the battery A in one regulation cycle of the system is optimal, the BC battery determines that the battery A is the host, the iterative fine regulation quantity is drawn close to the battery A as soon as possible, the regulation parameter exerts the optimal effect as soon as possible, when the regulation process is carried out to a certain degree, the regulation effect of the battery B is the best among the three groups of batteries, namely the charge state and the regulation demand quantity of the energy storage system enter a matching period, the multi-intelligent system judges that the battery B is the host, the batteries A and C are drawn close to the battery B in a fine regulation way, the coordinated operation of the three groups of batteries is ensured, and on the premise of intelligent regulation, a master-slave control mode of 'flexible change of the host' is established further according to the regulation precision requirement, so that the response time, and after adjustment, entering next circulation according to the flow until the required adjustment amount is reduced to be within the standard range, and recovering the energy storage system to be in the standby mode.
In summary, the energy storage unit of the system adjusts the power control through the state of charge, so as to ensure the coordinated operation of the three groups of batteries, and establish a master-slave control mode of "flexible host change". The overall adjustment of the system is based on the consistency criterion, on the premise of setting the adjustment precision, the host is used as the standard, the slave is used for iterative adjustment and is quickly closed, the reaction efficiency is improved, the optimal state of each group of batteries in the three groups of batteries under different adjustment quantities is exerted through the change of the adjustment quantity in the adjustment process, and the economical efficiency of the batteries in the three groups of different states and service lives is improved to the maximum extent while the speed and the precision are ensured.
Those skilled in the art should understand that they can make various changes, substitutions and alterations herein without departing from the scope of the invention as defined by the appended claims.
Claims (3)
1. A multi-agent lithium battery cluster energy storage system is formed by mutually connecting a plurality of lithium battery energy storage units, wherein each single lithium battery energy storage unit has the functions of data receiving and transmitting, data analysis and control signal receiving and transmitting; the system is characterized in that the system is in a double-loop control mode:
the inner loop is a single lithium battery self-feedback control link, droop control is added to output current based on a self-feedback regulation algorithm of each lithium battery, and current correction is set;
the outer ring is a multi-agent system control link, the lithium batteries which best meet the actual adjustment requirement are set as a host through mutual communication among the multiple lithium batteries, iteration is carried out based on a consistency algorithm, the energy storage units of the single lithium batteries are rapidly compared with each other, and a real-time master-slave relationship is generated; meanwhile, through the uninterrupted mutual communication and adjustment among the multiple intelligent agents, dynamic control instructions are generated for each lithium battery energy storage unit in real time.
2. The multi-agent lithium battery cluster energy storage system of claim 1, wherein: the self-feedback regulation algorithm of each lithium battery comprises the following steps:
(1) the charge capacity of all lithium batteries in the system is calculated, and the remaining capacity of the lithium batteries can be calculated according to the SOC, wherein the formula is as follows:
in the formula, S0The initial state of charge value of the lithium battery; eta is the coulomb efficiency of charging and discharging of the lithium battery in operation; i iscAnd IFThe current value of the lithium battery during charging and discharging is t1And t2；C1The self-loss discharge capacity of the lithium battery; c is the initial capacity of the lithium battery;
(2) calculating the SOC values of the N lithium battery energy storage units according to the formula1、SOC2、……、SOCNIn order to ensure the safe operation of the lithium battery, the state of charge value of the lithium battery is specified to be 20-80%, and the state of charge difference coefficient alpha of each lithium battery energy storage unit is definediComprises the following steps:
obtaining alpha by the above formulaiUsed for determining the power regulation of the lithium battery and then according to the power P of the lithium batterybatAdjusting the state of charge difference coefficient of the lithium battery, wherein an adjustment formula is obtained by calculating according to the following formula:
in the above formula, rbatiDenotes the ith rbatThe state of charge difference of the ith lithium battery energy storage system;
(3) according to the previously calculated state of charge values SOC of the N lithium battery energy storage units1、SOC2、……、SOCNThe SOC can be obtained by the following formulaaveI.e. the average state of charge value of the lithium battery pack:
according to the adjusted difference coefficient, the droop coefficient of each lithium battery energy storage unit is obtained as follows:
wherein beta is the initial droop coefficient, SOCaveThe average state of charge value of the lithium battery pack is obtained, so that the reference current value of the internal current loop in the feedback loop of each lithium battery energy storage unit can be obtained according to the average state of charge value:
Irefi＝ΔI-Ibatiμxbati
wherein, Delta I is the current value in the external current loop in the feedback loop of the lithium battery energy storage unit, IbatiFor the output current of the I-th group of lithium battery energy storage units, IbatiμxbatiThe current correction quantity of the lithium battery is obtained;
reference current value I of current inner ring designed according to state of charge of lithium batteryrefi(s), can be represented by the following formula:
in the above formula, UrefIs a reference voltage, i.e. the normal bus voltage when no regulation is required, UDCIs the real-time bus voltage; k is a radical ofpAnd kiRespectively as a proportional coefficient and an integral coefficient in the voltage and current double closed loop PI regulation,
forming a typical proportional-integral PI regulator, s is a transfer function of a controlled object and is determined by a specific waiting quantity of a system, UbatiOutputting voltage for the ith lithium battery energy storage unit in real time;
(4) at a reference current value IrefiIn the calculation of(s), a direct current motor characteristic function is introduced to increase certain inertia for the lithium battery energy storage system, so that frequent impact on the energy storage system caused by external disturbance can be prevented, and fluctuation is restrained; first of all, of building up a direct current motorA mathematical model represented by:
mathematic model formula of upper direct current motor, CTAnd phi are torque coefficient and magnetic flux respectively, and the universal value of the actual direct current motor is 5.1 and TeElectromagnetic torque, T, generated for the electric machinemMechanical torques, ω and ω, input to the motor0The actual mechanical angular velocity and the rated value of the DC motor, D the damping coefficient of the motor, g the inertia coefficient, and the unit is (kg.m)2) P is the electromagnetic power of the motor, and R is the equivalent internal resistance of the motor; and (3) carrying out the following calculation by using a mathematical model formula of the upper direct current motor:
the electromagnetic power P and the angular speed are in a relation of:
the deviation relationship between power P and ω can be derived from the above equation:
electromagnetic torque TeThe deviation relationship with the angular velocity ω is:
obtaining a transfer function G(s) of the control loop of the analog motor as follows:
Irefifeedback loop for ith lithium battery energy storage unitReference current value, mu, of the inner current loopxbatiAnd the droop coefficient of the ith lithium battery energy storage unit is shown.
3. The multi-agent lithium battery cluster energy storage system as recited in claim 1, wherein the consistency algorithm is generated based on graph theory, and information transfer among the plurality of lithium battery energy storage units is represented by a relational graph; g ═ V, E, denotes a graph, where V denotes a set of non-empty vertices,
representing a set of edges formed by node pairs, if information exchange can be carried out between the ith node and each jth node, the node pair is called to have a connecting edge, if each edge in the graph G has a direction, the graph G is called to be a directed graph, otherwise, the graph G is called to be an undirected graph; let G have an adjacency matrix A with aijFor the ith row and jth column element in the A matrix, when the node i can directly receive the information of the node j, aijIf the weight is more than 0, the connection weight of the nodes i and j is represented, if the weight cannot be received, the weight is less than zero, and if the two nodes are not interconnected, the weight is directly equal to zero; for an undirected graph, taking A as a symmetric array, a is when i ═ j or i and j are not interconnectedij0; a when i ≠ jij1 is ═ 1; in the graph theory, the number of edges pointing to a certain node is the in-degree of the node, the leaving is the out-degree, a matrix D is defined as an in-degree matrix, D is a diagonal matrix, and elements in D are expressed by the following formula:
for an undirected graph, the node in-degree and out-degree numbers are equal, D is a degree matrix in this case, the relationship between nodes and connected edges in the graph can be expressed by using laplace formula, L ═ D-a, and the following formula can be used:
D＝[dij]random moment of behaviorAn array, defined by:
when the lithium battery is charged and discharged, the following iteration factors and discharge modes can be obtained as initial values according to the working state of the lithium battery at the moment when the lithium battery receives the regulating instruction:
and (3) charging mode:
wherein
Discharging margin of the ith lithium battery energy storage unit;
calculating the iteration factors by an iteration formula in a consistency algorithm, wherein the iteration formula is as follows:
wherein Δ pdiffProviding an ideal reference direction for the difference between the scheduling command and the sum of the charge and discharge power of each lithium battery energy storage unit and the iteration of the consistency algorithm, wherein p is the ideal adjustment power of the 'host' in the unit time in the adjustment process, and p is the ideal adjustment power of the 'host' in the adjustment processiAdjusting the power for the actual of all the slaves in the unit time; dijThe meaning of (1) represents the relationship between the degree of entry and the degree of exit between any two of the multi-agent chemical lithium battery energy storage units; is the convergence factor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010883210.5A CN111969693A (en) | 2020-08-28 | 2020-08-28 | Multi-agent lithium battery cluster energy storage system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010883210.5A CN111969693A (en) | 2020-08-28 | 2020-08-28 | Multi-agent lithium battery cluster energy storage system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111969693A true CN111969693A (en) | 2020-11-20 |
Family
ID=73399701
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010883210.5A Pending CN111969693A (en) | 2020-08-28 | 2020-08-28 | Multi-agent lithium battery cluster energy storage system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111969693A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113097992A (en) * | 2021-04-28 | 2021-07-09 | 武汉工程大学 | Droop control method and device for direct-current micro-grid and computer storage medium |
| CN113346574A (en) * | 2021-05-19 | 2021-09-03 | 山东大学 | Energy storage battery cooperative control method and system |
| CN113555613A (en) * | 2021-07-15 | 2021-10-26 | 深圳市嘉洋电池有限公司 | Intelligent management system for battery pack clusters |
| CN113644328A (en) * | 2021-08-20 | 2021-11-12 | 北京宝龙德科技有限责任公司 | Flexible control method and device for dynamically reconstructing battery module |
| CN114301114A (en) * | 2021-12-10 | 2022-04-08 | 华为数字能源技术有限公司 | Lithium battery, lithium battery system and control method |
| CN114362288A (en) * | 2021-12-08 | 2022-04-15 | 深圳市科陆电子科技股份有限公司 | Battery inter-cluster balance adjusting method and system and storage medium |
| CN115313591A (en) * | 2022-10-10 | 2022-11-08 | 福建兴翼机械有限公司 | Battery control method, system, equipment, device and medium for electric grinding and polishing machine |
| WO2024092464A1 (en) * | 2022-10-31 | 2024-05-10 | 宁德时代新能源科技股份有限公司 | Battery mixed-use system and control method and control apparatus therefor, and storage medium |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107220752A (en) * | 2017-05-17 | 2017-09-29 | 东北电力大学 | Consider the lithium battery energy storage battery frequency modulation Cost accounting method of life-span impairment effect |
| CN107508277A (en) * | 2017-08-09 | 2017-12-22 | 华中科技大学 | A kind of light storage direct-current grid distributed collaboration control method based on uniformity |
-
2020
- 2020-08-28 CN CN202010883210.5A patent/CN111969693A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107220752A (en) * | 2017-05-17 | 2017-09-29 | 东北电力大学 | Consider the lithium battery energy storage battery frequency modulation Cost accounting method of life-span impairment effect |
| CN107508277A (en) * | 2017-08-09 | 2017-12-22 | 华中科技大学 | A kind of light storage direct-current grid distributed collaboration control method based on uniformity |
Non-Patent Citations (3)
| Title |
|---|
| 刘忠等: "基于一致性算法的直流微电网储能系统功率分配技术", 电力系统自动化, vol. 44, no. 7, pages 61 * |
| 王亚旭: "基于蓄电池储能优化及荷电状态均衡的直流微电网控制研究", 中国优秀硕士论文数据库, no. 8, pages 27 * |
| 赵霁晴: "飞轮储能阵列中各单元运行控制方法研究", 中国优秀硕士论文数据库, no. 1, pages 7 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113097992B (en) * | 2021-04-28 | 2022-07-26 | 武汉工程大学 | Droop control method and device for direct-current micro-grid and computer storage medium |
| CN113097992A (en) * | 2021-04-28 | 2021-07-09 | 武汉工程大学 | Droop control method and device for direct-current micro-grid and computer storage medium |
| CN113346574A (en) * | 2021-05-19 | 2021-09-03 | 山东大学 | Energy storage battery cooperative control method and system |
| CN113555613A (en) * | 2021-07-15 | 2021-10-26 | 深圳市嘉洋电池有限公司 | Intelligent management system for battery pack clusters |
| CN113644328A (en) * | 2021-08-20 | 2021-11-12 | 北京宝龙德科技有限责任公司 | Flexible control method and device for dynamically reconstructing battery module |
| CN113644328B (en) * | 2021-08-20 | 2023-10-24 | 刘铭新 | Flexible control method and device for dynamic reconfiguration battery module |
| CN114362288A (en) * | 2021-12-08 | 2022-04-15 | 深圳市科陆电子科技股份有限公司 | Battery inter-cluster balance adjusting method and system and storage medium |
| CN114362288B (en) * | 2021-12-08 | 2024-02-23 | 深圳市科陆电子科技股份有限公司 | Method, system and storage medium for regulating balance among battery clusters |
| CN114301114A (en) * | 2021-12-10 | 2022-04-08 | 华为数字能源技术有限公司 | Lithium battery, lithium battery system and control method |
| CN114301114B (en) * | 2021-12-10 | 2024-05-17 | 华为数字能源技术有限公司 | Lithium battery, lithium battery system and control method |
| CN115313591A (en) * | 2022-10-10 | 2022-11-08 | 福建兴翼机械有限公司 | Battery control method, system, equipment, device and medium for electric grinding and polishing machine |
| CN115313591B (en) * | 2022-10-10 | 2023-02-24 | 福建兴翼机械有限公司 | Battery control method, system, equipment, device and medium for electric grinding and polishing machine |
| WO2024092464A1 (en) * | 2022-10-31 | 2024-05-10 | 宁德时代新能源科技股份有限公司 | Battery mixed-use system and control method and control apparatus therefor, and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111969693A (en) | Multi-agent lithium battery cluster energy storage system | |
| Lin et al. | Controls of hybrid energy storage systems in microgrids: Critical review, case study and future trends | |
| Cai et al. | Distributed control scheme for package-level state-of-charge balancing of grid-connected battery energy storage system | |
| CN112600188B (en) | Multi-energy-storage SOC (system on chip) balanced segmentation self-adaptive droop control method for direct-current micro-grid | |
| CN110048438B (en) | Power distribution network feeder level load power control method based on model predictive control | |
| CN111509743A (en) | Control method for improving power grid stability by applying energy storage device | |
| CN111987713A (en) | Direct-current micro-grid improved droop control method based on charge state balance | |
| Huang et al. | Distributed optimal control of DC microgrid considering balance of charge state | |
| CN114914955A (en) | Active and reactive joint optimization scheduling method and system for microgrid | |
| CN115102239A (en) | Energy storage power station primary frequency modulation control method and system considering SOC balance | |
| Xu et al. | Research on the bi-level optimization model of distribution network based on distributed cooperative control | |
| CN114336694A (en) | Energy optimization control method for hybrid energy storage power station | |
| CN112039092A (en) | Island Direct Current (DC) outgoing Automatic Gain Control (AGC) model prediction control method considering energy storage System On Chip (SOC) recovery | |
| CN115313453A (en) | Multi-energy-storage-system coordination control method based on SOC improved droop control algorithm | |
| CN112865139B (en) | Optimization control strategy for energy storage power station to safely participate in primary frequency modulation of power grid | |
| CN114421479A (en) | Voltage control method for AC/DC micro-grid group cooperative mutual supply | |
| CN113346474B (en) | Double-energy-storage coordination control method for direct-current micro-grid and storage medium | |
| CN115441435A (en) | Method for energy storage system to participate in emergency control of second defense line of power grid based on critical cut set identification | |
| CN114362226A (en) | Distributed energy storage type MMC battery charge state three-level balance control strategy under complex working condition | |
| CN111585267A (en) | Novel ADRC hierarchical coordination control method based on single-phase photovoltaic energy storage all-in-one machine | |
| Ding et al. | Distributed Cooperative Control of Flywheel Energy Storage Systems for Power Distribution | |
| Haidar et al. | Analysis of grid-connected solar PV system operation based on energy router concept | |
| Alam et al. | An efficient voltage compensation and SoC-based power management in DC microgrid | |
| CN106340871B (en) | A kind of multistage closed loop control method of Novel DC voltage | |
| Tang et al. | Distributed Coordinated Control Battery Energy Storage System Based on Consensus Algorithm |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |