Multi-energy-storage-module SOC fast and balanced charging and discharging power distribution method and system

Abstract

The invention discloses a charging and discharging power distribution method and system for fast equalization of SOC of multiple energy storage modules, and the method comprises the steps: calculating the sum Esumt of the total target electric quantity of a system according to the load power PLoad, the remaining electric quantity Eir of each battery pack and the equalization time T, then distributing Esumt according to the proportion of the maximum available capacity Eimax of each battery pack, obtaining the target electric quantity Eit of each battery pack, and obtaining the maximum available capacity Eimax of each battery pack; finally determining the reference power of each battery pack; carrying out capacity over-limit judgment on the Esumt, determining whether an over-discharge problem occurs to a single energy storage module of the energy storage system or not, and if the corresponding problem exists, reducing the reference power of the energy storage module with the over-discharge problem by adopting a power distribution method under capacity over-limit; according to the invention, the SOC balance of the multi-energy storage module system can be realized under the condition of balancing the load power, and a good balance effect is achieved when the SOC difference value is small; when it is judged that the over-discharge problem exists, the normal operation time of the system can be prolonged, and the SOC balance degree of the system can be improved.

Description

Background Art

[0002] In order to solve the problem of unstable power generation of new energy sources in DC microgrids, such as the power output of photovoltaic systems depends on the surrounding light and temperature, and the power output of wind systems is affected by irregular wind speed, it has become a reliable method to set up energy storage devices in DC microgrid systems to smooth the power fluctuations of the system. Since the power fluctuations of new energy power generation systems require a certain scale of energy storage systems, multi-module scalable energy storage systems have received widespread attention. However, during the operation of the energy storage system, the maximum available capacity of the energy storage modules varies due to differences in battery pack manufacturing processes, environments, and operating conditions. Since the SOC balancing method that does not consider the maximum available capacity of each energy storage module will evenly distribute the load power to each energy storage module after SOC balancing, this will cause different SOC change rates of each energy storage module in the energy storage system with different maximum available capacity. Because the SOC change rates of each energy storage module are different after SOC balancing, the energy storage system will diverge and tend to an unbalanced state after SOC balancing, which will eventually lead to aggravated differences in the operating conditions of each energy storage module, resulting in problems such as reducing the service life of the energy storage unit and affecting the stable operation of the system. Therefore, a SOC-balanced charging and discharging power allocation method is needed that takes into account the maximum available capacity of each energy storage module.

[0003] Traditional droop control strategies are widely used in the state balancing of multiple energy storage units in energy storage systems. However, these traditional methods have reduced balancing efficiency when the state differences between energy storage units are small, which in turn prolongs the time required for the state balancing of the entire energy storage system. Long-term differences in operating conditions will exacerbate the problem of inconsistent battery pack performance. Therefore, it is very necessary to develop a charging and discharging power optimization allocation scheme for quickly achieving state balancing of multiple energy storage units. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a charging and discharging power distribution method and system for fast SOC balancing of multiple energy storage modules in view of the deficiencies in the above-mentioned prior art, and to perform reasonable power distribution according to the remaining power and maximum available capacity of each battery pack in the energy storage system, so as to solve the technical problem of long processing time of traditional droop SOC balancing control and improve the speed of SOC balancing when the SOC difference of multiple energy storage modules is small.

[0005] The present invention adopts the following technical solutions: A method for allocating charging and discharging power for fast SOC balancing of multiple energy storage modules comprises the following steps: Determine system load power P Load , No. i Battery Pack SOC i , Maximum available capacity Eimax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; According to each battery pack SOC i The battery groups are sorted in descending order, and the DC-DC converter control mode of the energy storage module with the largest SOC value is determined to be voltage control for stabilizing the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; According to the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; When the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit ; When the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; When the first i Reference power of DC-DC converter in energy storage module P * i When there is no power over-limit problem, record the reference power of the DC-DC converter P* i and equilibrium time T ; When the SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0006] Preferably, i The remaining power of the battery pack E ir and the total remaining power of the system E sumr They are:

[0007]

[0008] in, SOC i For the i The SOC of each battery pack, E imax For the i The maximum available capacity of a battery pack, is the number of energy storage modules.

[0009] Preferably, i Target capacity of battery pack E it Specifically:

[0010] in, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of E sumt is the total target power of the system.

[0011] Preferably, the total target power of the system E sumt for:

[0012] in, T For the equilibrium time, E sumr is the total remaining power of the system, P Load is the load power.

[0013] Preferably, the reference power of the converter in each energy storage module when the capacity exceeds the lower limit :

[0014] in, E ir For the n Group i The remaining charge of each battery pack, For the n The total remaining power of all battery packs in the group. P * nz For the n Group total reference power, P nz For the n Total rated power of the group.

[0015] Preferably, n Group total reference power P * nz :

[0016] in, P nm is an intermediate variable.

[0017] Preferably, i Reference power of DC-DC converter in energy storage module P * i for:

[0018] in, E ir For the i The remaining charge of each battery pack, E it For the i The target capacity of each battery pack, T For the equilibrium time.

[0019] Preferably, in step S6, when the first i Reference power of DC-DC converter in energy storage module P * i There is a problem of power over limit, increase the balancing time T , return to step S3 and recalculate.

[0020] Preferably, when When the SOC is not balanced, the balance time When SOC is balanced, the output power under balanced condition is P * i1 The calculation is as follows:

[0021] in, P Load is the system load power, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of .

[0022] In a second aspect, an embodiment of the present invention provides a charging and discharging power distribution system for fast SOC balancing of multiple energy storage modules, comprising: Parameter module, determines the system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; Sorting module, according to each battery pack SOC i The battery groups are sorted in descending order, and the DC-DC converter control mode of the energy storage module with the largest SOC value is determined to be voltage control for stabilizing the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; The power module obtains the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; Calculation module, when the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit; when the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; Control module, when i Reference power of DC-DC converter in energy storage module P * i When there is no power over-limit problem, record the reference power of the DC-DC converter P * i and equilibrium time T ; When SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0023] In a third aspect, a computer device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the above-mentioned method for rapidly balancing the SOC of multiple energy storage modules are implemented.

[0024] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, including a computer program, which, when executed by a processor, implements the steps of the above-mentioned method for rapidly balancing the SOC of multiple energy storage modules.

[0025] Compared with the prior art, the present invention has at least the following beneficial effects: A charging and discharging power allocation method for fast SOC balancing of multiple energy storage modules is provided. The power status of each energy storage module in the system when achieving SOC balancing is calculated according to the remaining power status and maximum available capacity of each energy storage module and the current load power of the energy storage system, and then the charging and discharging power of each energy storage module is calculated to achieve fast SOC balancing. When the SOC difference of multiple energy storage modules is small, a good balancing effect can be maintained, and the balancing time is shortened compared with the traditional droop control. At the same time, considering the problem that the energy storage system will diverge and tend to an unbalanced state after SOC balancing due to the different SOC change rates of each energy storage module after SOC balancing due to the difference in the maximum available capacity of each energy storage module, a method for allocating charging and discharging power according to the maximum available capacity of each energy storage module to achieve SOC balancing is added. Considering the problem of over-discharge of energy storage modules caused by the total target power of the system being lower than the lower limit of the capacity, a power allocation method is added when the total target capacity of the system exceeds the lower limit, which prolongs the normal operation time of the energy storage system in this case and improves the SOC balancing degree.

[0026] Further, through step S1, the first i Battery Pack SOC i , Maximum available capacity E imax The data is calculated i The remaining power of the battery pack E ir and the total remaining power of the system E sumr , in order to perform the calculation in step S3.

[0027] Furthermore, in order to determine the i Target capacity of battery pack E it , the system load power collected in step S1 P Load and the calculated total remaining power of the system E sumr Calculate the total target power of the system E sumt , and then according to i The maximum available capacity of the battery pack is calculated i Target capacity of battery pack E it .

[0028] Furthermore, when the calculated system target power appears E sumt Below the lower limit of total system capacity E l_lim In order to make the battery pack with a larger SOC bear more power, the battery packs in the system are divided into 4 groups according to the SOC size.P Load The reference power of each group is calculated based on the rated power of each group, and then the reference power of each battery group in the group is calculated based on the reference power of each group.

[0029] Furthermore, when the calculated system target power appears E sumt Greater than or equal to the lower limit of the total system capacity E l_lim , in order to calculate the i The reference power of the battery pack is calculated based on the first i The remaining power of the battery pack E ir , the first i Target capacity of battery pack E it and equilibrium time T Calculate the i The reference power of a battery pack.

[0030] Furthermore, since the reference power of each battery pack should not exceed the rated power of the DC-DC converter in each energy storage module, when the first i If the reference power of a battery pack exceeds the rated power of its corresponding DC-DC converter, the balancing time should be appropriately increased. T , and then return to step S3 to recalculate to reduce the i The reference power of each battery pack is calculated until there is no power over-limit problem, and the power output is kept as large as possible without exceeding the rated power of the corresponding DC-DC converter to achieve the purpose of rapid balancing.

[0031] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0032] In summary, the present invention calculates the power status of each energy storage module in the system when achieving SOC balance according to the remaining power status and maximum available capacity of each energy storage module and the current load power of the energy storage system, and then calculates the charge and discharge power of each energy storage module to achieve SOC rapid balance; when the SOC difference of multiple energy storage modules is small, it can maintain a good balance effect, and shorten the balance time compared to traditional droop control. At the same time, in the face of the difference in the maximum available capacity of each energy storage module, the SOC change rate of each energy storage module can be kept the same; considering the problem of over-discharge of energy storage modules caused by the total target power of the system being lower than the lower limit of the capacity, a power allocation method is added when the total target capacity of the system exceeds the lower limit, which prolongs the normal operation time of the energy storage system in this case and improves the SOC balance degree.

[0033] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings to be used in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 This is a hierarchical control structure diagram for the energy storage system; Figure 2 It is a flow chart of power calculation in an unbalanced state; Figure 3 It is the battery pack status diagram; Figure 4 The SOC and power waveforms of the three energy storage modules in the traditional droop control method, wherein (a) is the SOC waveform of the three energy storage modules in the traditional droop control method, and (b) is the power waveform of the three energy storage modules in the traditional droop control method; Figure 5 The SOC and power waveforms of the three energy storage modules when the capacity is not exceeded in the method of the present invention, wherein (a) is the SOC waveform of the three energy storage modules, and (b) is the power waveform of the three energy storage modules; Figure 6 This is a diagram showing the SOC changes of the three energy storage modules when the capacity exceeds the limit; Figure 7 A flow chart of a power allocation method for DC-DC converters in each energy storage module when the capacity exceeds the limit; Figure 8 A schematic diagram of a method for allocating power using over-capacity power for six energy storage modules when the capacity exceeds the limit; Fig. 9 A schematic diagram of a method for grouping battery packs by SOC in a power allocation method when capacity exceeds a limit; Fig.10 A schematic diagram of a computer device provided by an embodiment of the present invention; Fig.11 The present invention is a block diagram of an electronic device provided according to an embodiment. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0038] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0039] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0040] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0041] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0042] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0043] The present invention provides a method for allocating charging and discharging power of multiple energy storage modules SOC with fast balance, according to the load power P Load and the remaining capacity of each battery pack E ir and equilibrium time T Calculate the total target power of the system E sumt , then the maximum available capacity of each battery pack E imax Proportional Allocation E sumt , get the target power of each battery pack E it , and finally determine the reference power of each battery pack; E sumt Perform capacity over-limit judgment to determine whether a single energy storage module in the energy storage system has an over-discharge problem first. If this problem exists, use a power allocation method under capacity over-limit to reduce the reference power of the energy storage module with the over-discharge problem. The present invention can achieve SOC balance of a multi-energy storage module system under balanced load power, and achieve a good balancing effect when the SOC difference is small; when it is determined that there is an over-discharge problem, the power allocation method under capacity over-limit can maintain and extend the normal operation time of the system and improve the SOC balance of the system.

[0044] See also Figure 1 , is the hierarchical control structure diagram of the energy storage system. The energy storage system in the figure is N The energy storage modules are connected in parallel on the DC voltage bus to supply power to the load. The control structure is divided into a system-level control layer and a unit-level control layer. The system-level control layer obtains the system load power through communication. P Load , the remaining power of each battery pack E ir and maximum available capacity E imax , Balance time T , according to the equilibrium time T Determine the equilibrium state.

[0045] When the SOC is not balanced, the balance flag flag 0 (initialize the balance flag flag is 0, that is, unbalanced state); when it is determined that the SOC is balanced, the balance flag is set flag Set to 1; When the system-level control layer detects the balance flag flag When it is 0, the power calculation is performed in the unbalanced state. On the contrary, when the balanced flag is detected flag When it is 1, the power calculation is performed under the balanced state. SOC i Sort and select the battery pack with the largest SOC as the energy storage module with voltage control (the control mode flag is mode i is 1), the control mode of the remaining energy storage modules is power control (the control mode flag is mode i is 0).

[0046] In the unit-level control layer, each energy storage module receives the reference power output by the system-level control layer. P * i (After equilibrium P * i1 ) or reference voltage U * i And control mode flag mode i Finally, the charging and discharging of the energy storage module is controlled to achieve SOC balance.

[0047] See also Figure 2 The present invention provides a method for allocating charging and discharging power for fast SOC balancing of multiple energy storage modules, and the initial balancing time is set T 0.01s, obtain system load power through communication P Load , the remaining power of each battery pack E ir , calculate the total remaining power of the system E sumr , then calculate the total target power of the system E sumt ; Perform capacity over-limit judgment, capacity lower limit E l_lim 10% E sum ( Figure 3The battery pack status diagram sets that when SOC>90%, the battery pack is in an overcharged state, and when SOC<10%, the battery pack is in an over-discharged state). If the target capacity exceeds the lower limit, the power calculation under the capacity limit is performed to extend the normal operation time of the energy storage system in this case. If there is no problem of target capacity exceeding the limit, the reference power of the DC-DC converter in each energy storage module is calculated. P * i Then the power over-limit judgment is performed. If there is a problem that the reference power of a certain energy storage module exceeds the limit, the balancing time is increased. T , recalculate the total target power of the system E sumt , until there is no problem of over-power of any energy storage module, then the reference power command is output P * i and equilibrium time T , the calculated equilibrium time T The communication is transmitted to the system equilibrium state judgment module to judge the equilibrium state; the specific steps are as follows: S1. Determine the system load power P Load and i Battery Pack SOC i and maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr , which is the sum of the remaining power of all battery packs in the energy storage system; Calculate the i The remaining power of the battery pack E ir , as shown in formula (1): (1) in, SOC i For the i The SOC of each battery pack, E imax For the i The maximum available capacity of the battery pack.

[0048] Calculate the total remaining power in the energy storage system E sumr , as shown in formula (2): (2) in, is the number of energy storage modules.

[0049] S2, according to each battery pack SOC i Sort by large to small, determine that the DC-DC converter control mode of the energy storage module with the largest SOC value is voltage control to stabilize the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; S3: The total remaining power of the system obtained in step S1 E sumr and system load power P Load Calculate the total target power of the system E sumt , which is the sum of the target power of all battery packs in the energy storage system, and according to the i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; Calculate the total target power of the system E sumt , as shown in formula (3): (3) Among them, the equilibrium time T The initial setting is 0.01s. E sumr is the total remaining power of the system, load power P Load When it is positive, the energy storage system discharges for the load; the load power P Load When it is negative, the load charges the energy storage system.

[0050] Calculate the i Target capacity of battery pack E it , as shown in formula (4): (4) in, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of .

[0051] S4: Determine the total target power of the system obtained in step S3 Esumt Is there a lower limit on total capacity? E l_lim , that is, the problem of the capacity being lower than the lower limit, if it exists, skip the subsequent steps and directly calculate the reference power of the converter in each energy storage module when the capacity is lower than the lower limit, otherwise proceed to step S5 in sequence; Set the total capacity lower limit E l_lim 10% E sum ; When the calculated system total target power appears E sumt To solve the problem of the total capacity being lower than the lower limit, the battery packs in the system are divided into Group 4, Group 3, Group 2, and Group 1 according to the SOC range of 10%~30%, 30%~50%, 50%~70%, and 70%~90%. n ( n ∈1~4) Group has x n ( x n ≥0) energy storage battery packs, calculate the first n Total rated power P nz : (5) in, For the n Group i The rated power of each energy storage module.

[0052] Get the first n Total rated power P nz Then calculate the first n Group total reference power P * nz : (6) in, P nm is an intermediate variable, as shown in formula (7): (7) in, P Load is the load power, For the front n - The sum of the total rated power of 1 group, P jz For the j Total rated power of the group.

[0053] Get the total reference power of each groupP * nz Then calculate the first n Group i Reference power of energy storage modules : (8) in, E ir For the n Group i The remaining charge of each battery pack, For the n The total remaining power of all batteries in the group.

[0054] S5, the first i The remaining power of the battery pack E ir , the target power of the battery pack obtained in step S3 E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; Calculate the i Reference power of DC-DC converter in energy storage module P * i , as shown in formula (9): (9) in, E ir For the i The remaining charge of each battery pack, E it For the i The target capacity of each battery pack, T For the equilibrium time.

[0055] S6, judging the first i Reference power of DC-DC converter in energy storage module P * i Is there a power overlimit problem? If so, increase the balancing time. T , return to step S3 to recalculate, otherwise the reference power of the converter will be recorded P * i and equilibrium time T ; when If there is a power overlimit problem, the balancing time should be appropriately increased. T , return to step 3 and recalculate. If there is no power overlimit problem, record the reference power of the converter. P * i and equilibrium time T .

[0056] S7: Determine whether the SOC is balanced. If the SOC is balanced, calculate the reference power under balanced conditions. P * i1 Output to i The DC-DC converter control circuit in the energy storage module is used, otherwise the reference power calculated in step S6 is P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0057] When the equilibrium time When the balance degree is high, it means that the SOC is balanced and the output power under balanced condition is calculated. P * i1 , as shown in formula (10): (10) in, P Load is the system load power, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of .

[0058] when When the SOC is not balanced, the reference power calculated in step S6 is P * i The output is sent to the DC-DC converter control circuit for SOC fast balancing control.

[0059] See also Figure 3 , is the battery pack status diagram. In order to prevent the battery pack from overcharging and overdischarging, three states are set, namely: overdischarge protection state (battery pack status flag State is 1), normal state (battery pack status flag State 2), overcharge protection status (battery pack status flag State is 3).

[0060] When SOC>90%, the battery pack is in overcharge protection state, and the battery pack can only be discharged but not charged; When SOC<10%, the battery pack is in over-discharge protection state, and the battery pack can only be charged but not discharged. At the same time, in order to prevent the battery pack status flag from frequently switching the status flag when SOC=90% or SOC=10%, two hysteresis intervals are added at SOC=90% and SOC=10%.

[0061] It will be appreciated by those skilled in the art that various aspects of the present invention may be implemented as systems, methods or program products. Therefore, various aspects of the present invention may be specifically implemented in the following forms, namely: complete hardware implementation, complete software implementation (including firmware, microcode, etc.), or a combination of hardware and software implementations, which may be collectively referred to herein as "circuits", "modules" or "platforms".

[0062] In another embodiment of the present invention, a charging and discharging power distribution system for fast SOC balance of multiple energy storage modules is provided. The system can be used to implement the above-mentioned charging and discharging power distribution method for fast SOC balance of multiple energy storage modules. Specifically, the charging and discharging power distribution system for fast SOC balance of multiple energy storage modules includes a parameter module, a sorting module, a power module, a calculation module and a control module.

[0063] Among them, the parameter module determines the system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; Sorting module, according to each battery pack SOC i The battery groups are sorted in descending order, and the DC-DC converter control mode of the energy storage module with the largest SOC value is determined to be voltage control for stabilizing the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; The power module obtains the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the systemE sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; Calculation module, when the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit; when the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; Control module, when i Reference power of DC-DC converter in energy storage module P * i When there is no power overlimit problem, record the reference power of the converter P * i and equilibrium time T ; When SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0064] In another embodiment of the present invention, a terminal device is provided, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions to implement the corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used for the operation of the charging and discharging power distribution method for fast balancing of SOC of multiple energy storage modules, including: Determine system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; According to each battery pack SOC i Sort the battery packs in descending order, determine that the DC-DC converter control mode of the energy storage module with the largest SOC value is voltage control to stabilize the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; according to the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack Eit ; When the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit; when the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; When the first i Reference power of DC-DC converter in energy storage module P * i When there is no power overlimit problem, record the reference power of the converter P * i and equilibrium time T ; When SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0065] In another embodiment of the present invention, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a terminal device for storing programs and data. It is understandable that the computer-readable storage medium here can include both the built-in storage medium in the terminal device and the extended storage medium supported by the terminal device, and can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that more specific examples (non-exhaustive list) of the computer-readable storage medium here include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0066] Computer readable storage media also include data signals propagated in baseband or as part of a carrier wave, which carry readable program codes. Such propagated data signals can take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium can also be any readable medium other than a readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program code contained on the readable storage medium can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0067] Program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0068] The processor may load and execute one or more instructions stored in a computer-readable storage medium to implement the corresponding steps of the method for rapidly balancing the SOC of multiple energy storage modules in the above embodiment; the processor may load and execute the following steps: Determine system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; According to each battery pack SOC i Sort the battery packs in descending order, determine that the DC-DC converter control mode of the energy storage module with the largest SOC value is voltage control to stabilize the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; according to the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; When the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit; when the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate thei Reference power of DC-DC converter in energy storage module P * i ; When the first i Reference power of DC-DC converter in energy storage module P * i When there is no power overlimit problem, record the reference power of the converter P * i and equilibrium time T ; When SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

[0069] See also Fig.10 , the terminal device is a computer device, and the computer device 60 of this embodiment includes: a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61. When the computer program 63 is executed by the processor 61, the charging and discharging power distribution method for fast SOC balance of multiple energy storage modules in the embodiment is implemented. To avoid repetition, it is not described one by one here. Alternatively, when the computer program 63 is executed by the processor 61, the functions of each model / unit in the charging and discharging power distribution system for fast SOC balance of multiple energy storage modules in the embodiment are implemented. To avoid repetition, it is not described one by one here.

[0070] The computer device 60 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The computer device 60 may include, but is not limited to, a processor 61 and a memory 62. Those skilled in the art will appreciate that Fig.10 This is only an example of the computer device 60 and does not constitute a limitation of the computer device 60. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the computer device may also include input and output devices, network access devices, buses, etc.

[0071] The processor 61 may be a central processing unit (CPU), or other general-purpose processors, central processing units, graphics processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, data processing logic based on quantum computing, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0072] The memory 62 may be an internal storage unit of the computer device 60, such as a hard disk or memory of the computer device 60. The memory 62 may also be an external storage device of the computer device 60, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc., equipped on the computer device 60.

[0073] Furthermore, the memory 62 may include both an internal storage unit of the computer device 60 and an external storage device. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 may also be used to temporarily store data that has been output or is to be output.

[0074] Any reference to a memory, database or other medium used in the embodiments provided in the present application may include at least one of a non-volatile and a volatile memory. Non-volatile memory may include a read-only memory (ROM), a magnetic tape, a floppy disk, a flash memory, an optical memory, a high-density embedded non-volatile memory, a resistive random access memory (ReRAM), a magnetic random access memory (MRAM), a ferroelectric random access memory (FRAM), a phase change memory (PCM), a graphene memory, etc. Volatile memory may include a random access memory (RAM) or an external cache memory, etc. As an illustration and not limitation, RAM may be in various forms, such as a static random access memory (SRAM) or a dynamic random access memory (DRAM), etc.

[0075] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0076] See also Fig.11 The terminal device is an electronic device 600, and the electronic device is in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one processing unit 610, at least one storage unit 620, a bus 630 connecting different platform components (including the storage unit 620 and the processing unit 610), a display unit 640, etc.

[0077] The storage unit stores program codes, which can be executed by the processing unit 610, so that the processing unit 610 performs the steps according to various exemplary embodiments of the present invention described in the above method section of this specification. For example, the processing unit 610 can perform the following steps: Figure 2 Follow the steps shown in .

[0078] The storage unit 620 may include a readable medium in the form of a volatile storage unit, such as a random access memory unit (RAM) 6201 and / or a cache memory unit 6202 , and may further include a read-only memory unit (ROM) 6203 .

[0079] The storage unit 620 may also include a program / utility 6204 having a set (at least one) of program modules 6205, such program modules 6205 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0080] Bus 630 may represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

[0081] The electronic device 600 may also communicate with one or more external devices 700 (e.g., keyboards, pointing devices, Bluetooth devices, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 600, and / or communicate with any device that enables the electronic device 600 to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface 650. Furthermore, the electronic device 600 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 660. The network adapter 660 may communicate with other modules of the electronic device 600 via a bus 630. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 600, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms, etc.

[0082] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0083] Example 1 See also Figure 4 and Figure 5 , respectively, are the SOC and power waveforms of the three energy storage modules in the traditional droop control method and the method of the present invention; the rated voltage of the battery pack of the three energy storage modules is 144V, the maximum available capacity is set to 1.05Ah, 1.2Ah, and 1.5Ah respectively, and the load power P Load =2500W, the initial SOC of the three energy storage modules are set to 70%, 50% and 30% respectively. Figure 4 (a) is the SOC waveform of the three energy storage modules in the traditional droop control method. It can be seen from the figure that the SOC is balanced at around 70s. Figure 4 (b) is the power waveform of the three energy storage modules in the traditional droop control method. Figure 5 (a) is the SOC waveform of the three energy storage modules in the method of the present invention. It can be seen from the figure that the SOC is balanced at about 25s. Figure 5 (b) is a power waveform diagram of three energy storage modules in the method of the present invention.

[0084] Compared with the traditional droop control method, the method of the present invention can maintain a good balancing effect when the SOC difference of each energy storage module is small; and after SOC balancing, the system load power is distributed according to the difference in the maximum available capacity, and the energy storage module 3 with the largest maximum available capacity outputs a larger power, and the energy storage module 1 with the smallest maximum available capacity outputs a smaller power. It can be seen that in the energy storage system with the maximum available capacity difference, the method of the present invention can also reasonably allocate power to achieve rapid SOC balancing, and after balancing, reasonably allocate power according to the maximum available capacity difference to maintain the SOC balancing state.

[0085] Since the total target power of the system E sumt is a calculated value, and its calculation result may not conform to the actual physical meaning, that is, the total target power of the system exceeds the upper and lower limits of the total capacity of the system ( E sumt <0 or E sumt > E sum ) When the total remaining power of the system reaches E sumt When , it indicates that the system SOC reaches a balanced state, and there is a relationship as shown in formula (11): (11) in, E sumt is the total target power of the system, E sumMaximum available capacity of all battery packs E imax The sum of .

[0086] When the total target power of the system exceeds the upper and lower limits of the total capacity of the system, combined with formula (11), it is estimated that the SOC during balancing will be greater than 1 or less than 0, which does not conform to the actual physical meaning. At the same time, due to the setting of overcharge and over-discharge protection of the battery pack, when SOC>90% or SOC<10%, the battery pack is in overcharge or over-discharge protection state, the energy storage module stops charging and discharging, and the system will not work normally. Therefore, in the balancing process when the total target power of the system exceeds the upper and lower limits of the total capacity of the system, Figure 6 When the total target power of the system is greater than E u_lim (Capacity limit E u_lim 90% E sum ), the energy storage module with the largest SOC will reach the overcharge protection cutoff before other energy storage modules, and the system will not work properly; the total target power of the system is less than E l_lim When the energy storage module with the smallest SOC reaches the over-discharge protection cutoff before other energy storage modules, the system will not be able to work normally; since the charging power of the energy storage system can be adjusted, the system charging power can be adjusted to avoid the total target power of the system being greater than E u_lim Therefore, the total target power of the system exceeding the capacity limit is not included in the capacity limit judgment. E u_lim The judgment link. Since the discharge power of the energy storage system is determined by the system load power, this problem cannot be avoided. In order to extend the normal operation time and improve the SOC balance, the charging and discharging power distribution method of the DC-DC converter in each energy storage module under the capacity limit is calculated in step S4.

[0087] Figure 7 A flow chart of a power allocation method for DC-DC converters in each energy storage module when the capacity exceeds the limit; Figure 8 A schematic diagram of a method for allocating power in excess of capacity for six energy storage modules when the capacity exceeds the capacity limit; Fig. 9 Schematic diagram of a method for grouping battery packs by SOC in a power allocation method under capacity over-limit; a method for grouping battery packs by SOC; Figure 8 When the total target power of the system is less than E l_lim When the energy storage submodules SM1~SM6 are Fig. 9 The grouping method in is used to group and calculate the total rated power of each group P nz, and then calculate the total reference power of each group P * nz , and finally calculate the reference power of each group of energy storage modules P * ni , calculate the n Total rated power P nz , assuming that the group has x n Energy storage battery packs, x n ≥0; get n Total rated power P nz Calculate the next n Group total reference power P * nz ; Then calculate the first n Group total reference power P * nz Calculate the next n Group i Reference power of energy storage modules P * ni ; When the n Group total reference power P * nz At 0≤ P * nz ≤ P nz Within the range of i Remaining battery capacity E ir With n The total remaining power of all batteries in the group The power is distributed in proportion to the maximum available capacity. E imax and SOC i Power allocation is achieved based on . SOC i or maximum available capacity E imax The larger it is, the more power is allocated; SOC i or maximum available capacity E imax The smaller the value, the less power is allocated. When the SOC in the group tends to be consistent, the power allocation is based on the maximum available capacity. E imax With nThe total maximum available capacity of the group proportion, so that n The SOC of each battery group can remain consistent after balancing; n The SOC of each battery group (within the group) is balanced to improve the SOC balance.

[0088] See also Figure 8 , the 6 battery packs in the system are divided into 4 groups according to the SOC range of 10%~30%, 30%~50%, 50%~70%, and 70%~90%. SM1 is in the first group, SM3 and SM5 are in the second group, SM2 and SM4 are in the third group, and SM6 is in the fourth group. n Group total reference power P * nz , No. n Group i Reference power of energy storage modules P * ni The total reference power of group 1 and group 2 can be seen from the battery pack power distribution P * nz Total rated power P nz Equal, total reference power of group 3 P * 3z Less than the total rated power P 3z , total reference power of group 4 P * 4z is 0.

[0089] In summary, the present invention proposes a charging and discharging power distribution method and system for fast SOC balancing of multiple energy storage modules. When faced with the problem that the total target capacity of the system is lower than the lower limit, measures are taken to ensure that the energy storage modules with over-discharge problems reduce or avoid bearing the load power, while allowing the energy storage modules with higher SOC (state of charge) in the system to bear a larger share of the load power; the normal operation time of the system can be extended, and the overall balancing performance of the system can be improved.

[0090] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0091] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0092] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in the present invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0093] In the embodiments provided by the present invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0094] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0095] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0096] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0097] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0100] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for allocating charging and discharging power for fast SOC balancing of multiple energy storage modules, characterized in that: The following steps are involved: Determine system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; According to each battery pack SOC i The battery groups are sorted in descending order, and the DC-DC converter control mode of the energy storage module with the largest SOC value is determined to be voltage control for stabilizing the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; According to the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; When the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit ; When the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; When the first i Reference power of DC-DC converter in energy storage module P * i When there is no power over-limit problem, record the reference power of the DC-DC converter P * i and equilibrium time T ; When the SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

2. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 1 is characterized in that: No. i The remaining power of the battery pack E ir and the total remaining power of the system E sumr They are: in, SOC i For the i The SOC of each battery pack, E imax For the i The maximum available capacity of a battery pack, is the number of energy storage modules.

3. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 1, characterized in that: No. i Target capacity of battery pack E it Specifically: in, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of E sumt is the total target power of the system.

4. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 3 is characterized in that: System total target power E sumt for: in, T For the equilibrium time, E sumr is the total remaining power of the system, P Load is the load power.

5. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 1, characterized in that: Reference power of converters in each energy storage module when capacity exceeds the lower limit : in, E ir For the n Group i The remaining charge of each battery pack, For the n The total remaining power of all battery packs in the group. P * nz For the n Group total reference power, P nz For the n Total rated power of the group.

6. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 5 is characterized in that: No. n Group total reference power P * nz : in, P nm is an intermediate variable.

7. The method for allocating charging and discharging power for fast SOC balancing of multiple energy storage modules according to claim 1, characterized in that: No. i Reference power of DC-DC converter in energy storage module P * i for: in, E ir For the i The remaining charge of each battery pack, E it For the i The target capacity of each battery pack, T For the equilibrium time.

8. The method for rapidly balancing the SOC of multiple energy storage modules according to claim 1, characterized in that: In step S6, when the first i Reference power of DC-DC converter in energy storage module P * i There is a problem of power over limit, increase the balancing time T , return to step S3 and recalculate.

9. The method for allocating charging and discharging power for fast SOC balancing of multiple energy storage modules according to claim 1, characterized in that: when When the SOC is not balanced, the balance time When SOC is balanced, the output power under balanced condition is P * i1 The calculation is as follows: in, P Load is the system load power, E imax For the i The maximum available capacity of a battery pack, E sum Maximum available capacity of all battery packs E imax The sum of .

10. A charging and discharging power distribution system with fast SOC balance of multiple energy storage modules, characterized in that: include: Parameter module, determines the system load power P Load , No. i Battery Pack SOC i , Maximum available capacity E imax And its corresponding energy storage module rated power P i , and calculate the first i The remaining power of the battery pack E ir and the total remaining power of the system E sumr ; Sorting module, according to each battery pack SOC i The battery groups are sorted in descending order, and the DC-DC converter control mode of the energy storage module with the largest SOC value is determined to be voltage control for stabilizing the DC bus voltage, and the DC-DC converter control mode of the remaining energy storage modules is power control; The power module obtains the total remaining power of the system E sumr and system load power P Load Calculate the total target power of the system E sumt , and according to i Maximum available capacity of each battery pack E imax Calculate the target charge of its battery pack E it ; Calculation module, when the total target power of the system is obtained E sumt Below the total capacity limit E l_lim , calculate the reference power of the converter in each energy storage module when the capacity exceeds the lower limit ; When the total target power of the system is obtained E sumt Greater than or equal to the lower limit of total capacity E l_lim When, according to the obtained i The remaining power of the battery pack E ir 、Target power of battery pack E it and the required equilibrium time T Calculate the i Reference power of DC-DC converter in energy storage module P * i ; Control module, when i Reference power of DC-DC converter in energy storage module P * i When there is no power overlimit problem, record the reference power of the converter P * i and equilibrium time T ; When the SOC is not balanced, the calculated reference power P * i Output to i SOC fast balancing control is performed in the DC-DC converter of each energy storage module.

Images