Battery pack energy balancing control method, energy balancing system and storage medium

Abstract

This application relates to the field of energy balancing technology, and more particularly to a battery pack energy balancing control method, energy balancing system, and storage medium. The embodiments of this application dynamically and adaptively determine the polling frequency of the battery pack's state of charge (SOC) value. By collecting the SOC value of the battery pack at a dynamically changing polling frequency, it adapts to battery packs with different SOC changes, enabling rapid response and execution of energy balancing operations. It calculates the average SOC value of all battery packs and uses this average SOC value to calculate the total deficit of all depleted packs and the total surplus of all charged packs. By combining the SOC value of the master pack with the relationship between the total surplus and total deficit, it performs charging and discharging operations between the master and slave packs. This facilitates flexible and timely energy balancing of the battery packs, improving system safety and stability.

Description

Technical Field

[0001] This application relates to the field of energy balancing technology, and in particular to a battery pack energy balancing control method, energy balancing system and storage medium. Background Technology

[0002] With the rapid development of the new energy industry, lithium-ion battery packs, as core components of energy storage systems and power systems, are widely used in electric vehicles, energy storage power stations, and home energy storage. Due to the limitations of the voltage platform of individual cells, practical applications typically require combining a large number of individual cells in series and parallel to form high-capacity, high-voltage battery packs. However, during the lifespan of a battery pack, inconsistencies in the State of Charge (SOC) between different battery packs can occur due to differences in manufacturing processes, operating temperature gradients, charge / discharge rates, and aging rates.

[0003] Energy imbalances between battery packs can significantly reduce the overall usable capacity of the battery pack, shorten its lifespan, increase the risk of thermal runaway, and affect the system's output power. Related technologies typically use the same fixed frequency to collect the state of charge (SOC) values ​​of all battery packs. This mechanism is rigid, lacks dynamic adaptability, and cannot promptly detect SOC imbalances. It also fails to identify and address battery packs with large or low SOC fluctuations that require close monitoring, resulting in delayed energy balancing. Summary of the Invention

[0004] One objective of this application is to provide a battery pack energy balancing control method, energy balancing system, and storage medium, so as to dynamically and adaptively determine the polling frequency for collecting the state of charge values ​​of the battery pack, which is beneficial to timely and flexibly balancing the energy of multiple battery packs to improve system safety and stability.

[0005] In a first aspect, embodiments of this application provide a battery pack energy balancing control method for balancing the energy among multiple battery packs. The multiple battery packs are divided into a master pack and at least one slave pack. The energy balancing control method includes: during the energy balancing control process, determining a polling frequency for collecting data from each battery pack at preset time intervals based on the state of charge (SCC) value and rate of change of SCC value of each battery pack; determining a first average SCC value based on the average SCC value of all battery packs collected during the polling; and determining the total SCC value of all SCC packs based on the sum of the differences between the SCC value of each depleted battery pack and the first average SCC value. The system defines a slave battery pack as having a state of charge (SOC) value less than or equal to a first average SOC value. The total surplus capacity of all slave battery packs is determined based on the sum of the differences between the SOC value of each fully charged battery pack and the first average SOC value. A fully charged battery pack is defined as a slave battery pack with a SOC value greater than the first average SOC value. When the total SOC value is less than or equal to the SOC value of the master battery pack, charging and discharging operations are performed between multiple battery packs to achieve energy balance, based on the total SOC value and the SOC value of each battery pack. When the total SOC value is greater than the SOC value of the master battery pack, charging and discharging operations are performed between multiple battery packs to achieve energy balance, based on the total surplus capacity and the SOC value of each battery pack.

[0006] In some embodiments, based on the total power loss and the state of charge (SOC) value of each battery pack, charging and discharging operations are performed among multiple battery packs to achieve energy balancing, including: determining a first target charging amount for each power-loss pack based on the difference between a first average SOC value and the SOC value of each power-loss pack; charging each power-loss pack using the main pack with the charging amount of each power-loss pack being the first target charging amount for that power-loss pack, so that all power-loss packs are charged to the first average SOC value; and charging the main pack using all the power-charged packs to balance the energy of the main pack to a second average SOC value, the second average SOC value being determined based on the SOC value of the main pack after discharge and the SOC values ​​of all the power-charged packs.

[0007] In some embodiments, charging the main pack using all the charged packs to equalize the energy of the main pack to a second average charge value includes: determining a second average charge value based on the state of charge (SOC) value of the main pack after discharge and the average SOC values ​​of all the charged packs; determining the total amount of charging to be done for the main pack based on the difference between the second average charge value and the SOC value of the main pack after discharge; determining a first target discharge amount for each charged pack based on the product of the total charging amount and a first discharge weight for each charged pack; charging the main pack using each charged pack and the discharge amount of each charged pack being the first target discharge amount for that charged pack, so that the main pack is charged to the second average charge value; the first discharge weight for each charged pack is the ratio of the SOC value of that charged pack to a first total energy, and the first total energy is the sum of the SOC values ​​of all the charged packs.

[0008] In some embodiments, based on the total surplus capacity and the state of charge (SOC) value of each battery pack, charging and discharging operations are performed among multiple battery packs to achieve energy balance, including: subtracting the SOC value of the main pack from the SOC value corresponding to the full capacity value to obtain the maximum chargeable amount of the main pack; determining a second target discharge amount for each battery pack based on the maximum charge amount, the total surplus capacity, and the SOC value of each battery pack; charging the main pack using each battery pack, with the discharge amount of each battery pack being the second target discharge amount of that battery pack, so that the main pack is charged to the SOC value corresponding to the full capacity value; and charging all depleted battery packs using the charged main pack, so that the energy of the main pack is balanced to a third average SOC value and all depleted battery packs are charged to a third average SOC value, wherein the third average SOC value is determined based on the SOC value of the charged main pack and the SOC values ​​of all depleted battery packs.

[0009] In some embodiments, determining a second target discharge amount for each battery pack based on the maximum charge amount, the total charge capacity, and the state of charge (SCC) value of each battery pack includes: in response to the maximum charge amount being greater than or equal to the total charge capacity, determining the second target discharge amount for each battery pack as the difference between the SCC value of the battery pack and a first average charge value; in response to the maximum charge amount being less than the total charge capacity, determining the second target discharge amount for each battery pack as the product of a second discharge weight for each battery pack and the maximum charge amount; the second discharge weight for each battery pack is the ratio of the SCC value of the battery pack to the second total charge capacity, and the second total charge capacity is the sum of the SCC values ​​of all battery packs.

[0010] In some embodiments, the main battery is charged to all depleted batteries to balance the energy of the main battery to a third average charge value and to charge all depleted batteries to the third average charge value. This includes: determining a third average charge value based on the state of charge (SOC) value of the main battery after charging and the average SOC values ​​of all depleted batteries; determining the total discharge amount to be discharged from the main battery based on the difference between the SOC value of the main battery after charging and the third average charge value; determining a second target charge amount for each depleted battery based on the product of the total discharge amount and the charging weight of each depleted battery; charging each depleted battery with the main battery after charging, and the charge amount for each depleted battery is the second target charge amount for that depleted battery, to balance the energy of the main battery to a third average charge value and to charge all depleted batteries to the third average charge value; the charging weight of each depleted battery is inversely proportional to the SOC value of that depleted battery.

[0011] In some embodiments, the method further includes: sorting all depleted packets according to their state-of-charge values ​​in ascending order to obtain a packet sequence; determining the first packet in the packet sequence. The ratio of the state of charge of the first depleted battery to the total charge of the third battery is the first The charging weight of a depleted battery pack. , The number of power-deficient units is denoted by , and the third total power is the sum of the state-of-charge values ​​of all power-deficient units.

[0012] In some embodiments, based on the state of charge (SCC) value and rate of change of SCC value of each battery pack, the polling frequency for collecting data from each battery pack during the energy balancing control process is determined, including: determining a preset first frequency as the polling frequency of the battery pack in response to the SCC value of the slave pack being less than a preset SCC threshold; determining a preset second frequency as the polling frequency of the slave pack in response to the SCC value of the slave pack being greater than or equal to the SCC threshold and the rate of change of SCC value of the slave pack being greater than or equal to the preset SCC threshold; and determining a preset third frequency as the polling frequency of the slave pack in response to the SCC value of the slave pack being greater than or equal to the SCC threshold and the rate of change of SCC value of the slave pack being less than the SCC threshold, wherein the first frequency is greater than the second frequency and the second frequency is greater than the third frequency.

[0013] In some embodiments, after determining the first target charging amount or the second target charging amount for each power-deficient pack, the energy balancing control method further includes: during each charging process of the power-deficient pack, determining the balancing duration for each power-deficient pack based on the number of power-deficient packs and a reference power-deficient difference, wherein the reference power-deficient difference is the difference between the minimum value of the state of charge (SOC) values ​​of all power-deficient packs and the first average value or the third average value of the SOC; sorting the SOC values ​​of all power-deficient packs from smallest to largest to obtain the charging priority of all power-deficient packs, wherein the power-deficient pack with the smaller SOC value has a higher charging priority; and controlling all power-deficient packs to be charged alternately according to the balancing duration and charging priority of each power-deficient pack.

[0014] In some embodiments, the balancing time of each power-deficient package is determined based on the number of power-deficient packages and a reference power-deficient difference, including: obtaining an alternation ratio based on the ratio of the reference power-deficient difference to the number of power-deficient packages; and obtaining the balancing time based on the product of a preset proportional coefficient and the alternation ratio.

[0015] Secondly, embodiments of this application provide an energy balancing system, comprising: Multiple battery packs, including one master pack and at least one slave pack; An equalization controller includes at least one DAB converter, each of the DAB converters having one end connected to the master packet and the other end connected to a slave packet; A processor connected to the equalization controller, the processor being configured to execute the battery pack energy equalization control method provided in the first aspect.

[0016] Thirdly, embodiments of this application provide a computer-readable storage medium storing processor-executable computer program instructions, which, when executed by the processor, cause the processor to perform the battery pack energy balancing control method provided in the first aspect.

[0017] The embodiments of this application have the following beneficial effects: Unlike related technologies, the embodiments of this application dynamically and adaptively determine the polling frequency of the battery pack's state of charge (SOC) value. By polling the battery pack's SOC value at a dynamically changing frequency, the embodiments can adapt to battery packs with different SOC changes, enabling rapid response to perform energy balancing operations, calculate the average SOC value of all battery packs, and use the average SOC value to calculate the total deficit of all depleted packs and the total surplus of all charged packs. By combining the SOC value of the main pack with the relationship between the total surplus and total deficit, charging and discharging operations are performed between the main pack and the slave packs. This facilitates flexible and timely energy balancing of the battery packs, improving system safety and stability. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the accompanying drawings used in the description of the related technologies or embodiments will be briefly introduced below. Obviously, the drawings described below only show some embodiments of this application and should not be considered as limiting the scope of protection. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram illustrating the application scenario of battery pack energy balancing in some embodiments of this application; Figure 2 This is a schematic diagram of the structure of an energy balancing system provided in some embodiments of this application; Figure 3 This is a schematic flowchart of a battery pack energy balancing control method provided in some embodiments of this application; Figure 4 yes Figure 3 A schematic diagram of a sub-process of step S31 in the battery pack energy balance control method shown in the embodiment; Figure 5 This is a flowchart illustrating a battery pack energy balance control method provided in other embodiments of this application; Figure 6 This is a flowchart illustrating a battery pack energy balance control method provided in some embodiments of this application. Detailed Implementation

[0020] To make the objectives and advantages of the embodiments of this application more readily understood, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The detailed description of the embodiments of this application in the accompanying drawings is not intended to limit the scope of protection claimed by this application, but only represents selected embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that, unless there is a conflict, the various technical features involved in the embodiments of this application described below can be combined with each other, and all are within the protection scope of this application. Furthermore, although functional modules are divided in the device or structural schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. In addition, the terms "first," "second," "third," and other similar expressions used herein do not limit the data or execution order, but are only for illustrative purposes and to distinguish identical or similar items with substantially the same function and effect, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features.

[0022] Unless otherwise defined, the technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. It should be understood that the term "and / or" as used in this specification includes any and all combinations of one or more of the listed items.

[0023] With the rapid development of the new energy industry, lithium-ion battery packs, as core components of energy storage systems and power systems, are widely used in electric vehicles, energy storage power stations, and home energy storage. Due to limitations in the voltage platform of individual cells, practical applications typically require combining a large number of individual cells in series and parallel to form high-capacity, high-voltage battery packs. However, during the battery pack's lifespan, inconsistencies in the State of Charge (SOC) between battery packs arise due to differences in manufacturing processes, operating temperature gradients, charge / discharge rates, and aging rates. To address these issues, battery equalization management systems have emerged. In a "one master, multiple slave" battery pack system (i.e., one master battery pack and multiple slave battery packs), equalization control is a key technology for ensuring consistency among battery packs and extending cycle life.

[0024] In related technologies, the equalization control method is as follows: The main battery pack is responsible for overall management and decision-making, while each slave battery pack collects its voltage, current, and SOC parameters. The main battery pack cycles through each slave battery pack according to a preset fixed sequence or fixed period, collecting SOC data from each slave battery pack. The main battery pack compares the collected SOC of all battery packs to determine the highest SOC value (SOCmax) and the lowest SOC value (SOCmin). When the difference between the highest and lowest SOC values ​​(ΔSOC) exceeds the SOC equalization start threshold, the main battery pack determines that the system is in an unbalanced state. The main battery pack locks the two battery packs with the highest and lowest current SOC and sends commands to these two battery packs to activate the bidirectional active equalization circuit connected between them, so that energy is transferred from the high SOC battery pack to the low SOC battery pack. During the equalization execution, the main battery pack maintains a cycle monitoring of all battery packs. If it detects that ΔSOC has fallen below the SOC equalization shutdown threshold, the main battery pack sends a command to cut off the equalization circuit and end the current equalization process.

[0025] Energy imbalances between battery packs can significantly reduce the overall usable capacity of the battery pack, shorten its lifespan, increase the risk of thermal runaway, and affect the system's output power. Related technologies typically use the same fixed frequency to collect the state of charge (SOC) values ​​of all battery packs. This mechanism is rigid, lacks dynamic adaptability, and cannot promptly detect SOC imbalances. It also fails to identify and address battery packs with large or low SOC fluctuations that require close monitoring, resulting in delayed energy balancing of the battery packs.

[0026] In view of this, embodiments of this application provide a battery pack energy balancing control method. By dynamically and adaptively determining the polling frequency of the battery pack's state of charge (SOC) value, the SOC value of the battery pack is collected in a dynamically changing polling frequency. This adapts to battery packs with different SOC changes, enabling rapid response and execution of energy balancing operations. The method calculates the average SOC value of all battery packs and uses this average SOC value to calculate the total deficit of all depleted packs and the total surplus of all charged packs. By combining the SOC value of the master pack with the relationship between the total surplus and total deficit, charging and discharging operations are performed between the master and slave packs. This facilitates flexible and timely energy balancing of the battery packs, improving system safety and stability.

[0027] Please refer to the following: Figure 1 and Figure 2 , Figure 1 This illustration schematically depicts an application scenario of battery pack energy balancing in some embodiments of this application. Figure 2 A schematic diagram of the structure of an energy balancing system in some embodiments of this application is shown.

[0028] like Figure 1As shown, the application scenario includes an energy balancing system 100, which can be various suitable types of equipment or devices such as energy storage systems and battery systems.

[0029] The energy balancing system 100 includes multiple battery packs, a balancing controller 120, and a processor 130. The multiple battery packs include a master pack 111 and at least N slave packs 112. The balancing controller 120 includes multiple (N) DAB converters 121, each DAB converter 121 having one end connected to the master pack 111 and the other end connected to a slave pack 112 (i.e., the first end of a DAB converter 121 is connected to the master pack 111, and the second end of the DAB converter 121 is connected to a slave pack 112). Here, N is an integer greater than or equal to 1.

[0030] The DAB (Dual Active Bridge) converter 121 is a high-frequency isolated, bidirectional DC-DC converter. The DC circuit utilizes phase-shift control to achieve bidirectional, efficient, and isolated energy transfer. Of course, the equalization controller 120 can also employ any other suitable isolated DC-DC circuit; this application embodiment does not impose any limitations on this.

[0031] Understandably, at least one DAB converter 121 forms a DAB array, with one end of each DAB converter 121 in the DAB array connected to the main package 111 and the other end connected to a switch. Figure 2 (Not shown) A slave packet 112 is connected to form an energy balancing path. After the switch corresponding to the energy balancing path is turned on, energy is transferred between the master packet 111 and the slave packet 112. In this embodiment, no two slave packets 112 can transfer energy to each other. The balancing controller 120 includes a DAB converter array, which has fast response and multi-channel time-division switching capabilities, and can meet the requirements of fast response and alternating balancing.

[0032] It should be understood that the main pack 111 and the slave pack 112 are equipped with a variety of sensors to detect and collect various different status data of the battery pack, such as temperature sensors, current sensors, voltage sensors, etc., to detect and collect the temperature, current, voltage, etc. of the battery pack respectively.

[0033] In this embodiment of the application, the processor 130 is connected to the equalization controller 120, and the processor 130 is configured to execute the battery pack energy equalization control method provided in this embodiment of the application.

[0034] Specifically, processor 130 is configured to provide computational and control capabilities to support the energy balancing system 100 in executing corresponding business logic and functions. For example, it supports the energy balancing system 100 in executing the battery pack energy balancing control method provided in this application embodiment, or in executing the steps of any possible implementation of the battery pack energy balancing control method provided in this application embodiment. It is understood that processor 130 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc., and can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0035] In some other embodiments, the energy balancing system 100 also includes a memory 140 connected to the processor 130.

[0036] The memory 140, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, instructions, and modules, such as the program, instructions, and modules corresponding to the battery pack energy balancing control method in the embodiments of this application. In some embodiments, the memory 140 may include a program storage area and a data storage area. The program storage area may store an operating system, an application program required for at least one function, and the data storage area may store data created according to the use of the processor 130. The processor 130 executes various functional applications and data processing of the energy balancing system 100 by running the non-transitory software programs, instructions, and modules stored in the memory 140, thereby implementing the battery pack energy balancing control method provided in the embodiments of this application, or executing the steps in any possible implementation of the battery pack energy balancing control method provided in the embodiments of this application. In some embodiments, the memory 140 may include high-speed random access memory and may also include non-transitory memory. For example, at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 140 may also include memory remotely located relative to the processor 130, and these remotely located memories may be connected to the processor 130 through a communication network. It is understood that examples of the aforementioned communication networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0037] For example, the energy balancing operation performed in this application embodiment is as follows: based on the state of charge value and the rate of change of state of charge of each battery pack, the round-robin frequency of collecting data from each battery pack during the energy balancing control process is determined.

[0038] Next, the battery pack is cycled at the same cycle frequency to collect its state of charge (SOC) value. The average SOC value of all battery packs collected during the cycle is then calculated to obtain the first average SOC value.

[0039] Packets whose state of charge (SCC) value is less than or equal to the first average SCC value are identified as low-charge packs. The difference between each low-charge pack and the first average SCC value is calculated. The sum of the differences between the SCC values ​​of all low-charge packs and the first average SCC value is obtained to get the total low charge of all low-charge packs.

[0040] Packets with a state of charge value greater than the first average charge value are identified as "charged" packets. The difference between each charged packet and the first average charge value is calculated. The sum of the differences between the state of charge value and the first average charge value of all charged packets is obtained to get the total charge of all charged packets.

[0041] Finally, the total power deficit is compared with the state of charge (SOC) value of the main battery pack. When the total power deficit is less than or equal to the SOC value of the main battery pack, charging and discharging operations are performed between multiple battery packs based on the total power deficit and the SOC value of each battery pack to achieve energy balance.

[0042] When the total power deficit exceeds the state of charge (SOC) of the main battery pack, charging and discharging operations are performed between multiple battery packs based on the total power surplus and the SOC of each battery pack to achieve energy balance.

[0043] The above method enables rapid response and execution of energy balancing operations, flexibly and promptly balancing the energy of multiple battery packs.

[0044] It should be understood that, Figure 1 and Figure 2 The illustrated embodiments are merely illustrative of one scenario where the energy balancing system 100 balances the energy of a battery pack in some embodiments of this application, and do not limit the structure, type, or quantity of the energy balancing system in other embodiments. For example, in some other embodiments, the energy balancing system may also include a... Figure 2 The structure shown has more or fewer components, or has the same Figure 2 The diagram shows different configurations of the structure.

[0045] As can be understood from the above, the battery pack energy balancing control method provided in this application embodiment can be implemented by any suitable type of processor with certain computing and control capabilities, such as the processor 130 described above. In some feasible implementations, the battery pack energy balancing control method provided in this application embodiment can be implemented by the processor executing computer program instructions stored in the memory.

[0046] The following will describe in detail the battery pack energy balance control method provided in this application embodiment, with reference to exemplary applications and implementations of the energy balance system provided in the embodiments of this application.

[0047] See Figure 3 As shown, the battery pack energy balancing control method provided in this application embodiment includes steps S31 to S36 to achieve battery pack energy balancing.

[0048] Step S31: During the energy balance control process, at each preset time interval, based on the state of charge value and state of charge change rate of each battery pack, the polling frequency of each battery pack is determined during the energy balance control process.

[0049] Each battery pack is equipped with a corresponding battery management unit (BMU), which is used to monitor and collect the operating parameters of the corresponding battery pack in real time and report the state of charge (SOC) value of the battery pack. It should be understood that the rate of change of SOC characterizes the speed at which the SOC value of the battery pack changes.

[0050] For example, in the energy balance control process, this embodiment acquires the current state of charge (SOC) value of each battery pack at preset time intervals and records the corresponding acquisition timestamp. For any battery pack, the SOC change rate is calculated based on the current SOC value and the previous SOC value. The SOC change rate is the ratio of the SOC difference (i.e., the difference between the current SOC value and the previous SOC value) to the target interval. The target interval is easily understood as the time interval between the acquisition timestamp of the current SOC value and the acquisition timestamp of the previous SOC value. Engineers can customize the preset time according to actual needs. The preset time characterizes the update interval of the polling frequency for each battery pack.

[0051] Based on the state of charge (SCC) value of each battery pack, the corresponding SCC level is determined. For example, in this embodiment, multiple SCC intervals are pre-defined, and a correspondence is established between these intervals and SCC levels. For instance, a SCC value greater than a first threshold is determined to be a high SCC level; a SCC value between the first and second thresholds is determined to be a medium SCC level; and a SCC value less than the second threshold is determined to be a low SCC level. The first threshold is greater than the second threshold.

[0052] Similarly, the rate of change of state of charge (SOC) for each battery pack is determined based on its rate of change. For example, this application embodiment pre-sets multiple rate of change intervals and establishes a correspondence between these intervals and rate of change levels. For instance, when the SOC change rate is greater than a first rate of change threshold, it is determined to be a rapid change level; when the SOC change rate is between the first and second rate of change thresholds, it is determined to be a medium-speed change level; and when the SOC change rate is less than the second rate of change threshold, it is determined to be a slow change level. The first rate of change threshold is greater than the second rate of change threshold.

[0053] The polling priority for each battery pack is determined based on its state of charge (SOC) level and rate of change (RCO) level. For example, this application embodiment pre-establishes a priority mapping table, where a lower SOC value corresponds to a higher polling priority, and a higher RCO rate corresponds to a higher polling priority. For instance, when a battery pack has a low SOC level and a rapidly changing RCO level, the highest polling priority is determined as the polling priority for that battery pack.

[0054] The polling frequency of each battery pack is determined based on its polling priority. The first priority corresponds to the first polling frequency, the second priority to the second polling frequency, and the third priority to the third polling frequency. The first polling frequency is higher than the second polling frequency, and the second polling frequency is higher than the third polling frequency; that is, the higher the polling priority of a battery pack, the higher its polling frequency. When a battery pack has the first polling priority, the first polling frequency is determined as its polling frequency. Polling data acquisition is performed on each battery pack according to its determined polling frequency, and the polling frequency of each battery pack is dynamically updated during the energy balancing control process.

[0055] By considering both the state of charge (SOC) value and the rate of change of SOC value of the battery pack, different polling frequencies are configured for different battery packs. The polling frequency is increased for battery packs with faster SOC value changes, and decreased for battery packs with slower SOC value changes. In this way, system resources are preferentially allocated to battery packs with faster SOC value changes or abnormal SOC values, improving the real-time performance of data acquisition in the energy balancing control process, enhancing the accuracy of balancing control, and reducing communication bandwidth usage and processor computational load.

[0056] See Figure 4 As shown, in this embodiment of the application, steps S311 to S313 are used to determine the round-robin frequency of collecting data for each battery pack during the energy balance control process based on the state of charge value and the rate of change of state of charge of each battery pack.

[0057] Step S311: In response to the state of charge value of the slave packet being less than a preset state of charge threshold, a preset first frequency is determined as the polling frequency of the slave packet.

[0058] Step S312: In response to the state of charge value of the slave packet being greater than or equal to the state of charge threshold and the rate of change of the state of charge of the slave packet being greater than or equal to the preset state of charge change threshold, a preset second frequency is determined as the polling frequency of the slave packet.

[0059] Step S313: In response to the state of charge value of the slave packet being greater than or equal to the state of charge threshold and the rate of change of the state of charge of the slave packet being less than the state of charge change threshold, a preset third frequency is determined as the polling frequency of the slave packet.

[0060] In this embodiment, the first frequency Greater than the second frequency Second frequency Greater than the third frequency ,Right now: Engineers can customize and set the state of charge threshold, first frequency, second frequency, and third frequency based on experimental data and actual needs.

[0061] For example, for the first One from the package, when the first The state of charge value of each packet Less than the state of charge threshold At that time, that is: , indicating the first One packet is in an undervoltage state and needs to be collected in a polling process with the highest priority. The state of charge value of each packet is used to determine the preset first frequency. For the first The frequency of each package's rotation .

[0062] For example, for the first One from the package, when the first The state of charge value of each packet Greater than or equal to the state of charge threshold And the first Rate of change of state of charge of each packet Greater than or equal to a preset threshold for change in state of charge At that time, that is: and , indicating the first The packet is in a non-undervoltage state, according to the first... Rate of change of state of charge of each packet Determine the first The frequency of each package's rotation Thus, the preset second frequency is determined. For the first The frequency of each package's rotation .

[0063] For example, for the first One from the package, when the first The state of charge value of each packet Greater than or equal to the state of charge threshold And the first Rate of change of state of charge of each packet Less than the threshold for change of state of charge At that time, that is: and , indicating the first If the packet is in a non-undervoltage state, then according to the first... Rate of change of state of charge of each packet Determine the first The frequency of each package's rotation Thus, the preset third frequency is determined. For the first The frequency of each package's rotation .

[0064] Step S32: Determine the first average charge value based on the average state of charge value of all battery packs collected in the round-robin survey.

[0065] For example, in this embodiment of the application, the average value of the state of charge of all battery packs collected in the round-robin process is calculated to obtain the first average value of charge.

[0066] In some embodiments, according to the following first formula: The first average charge value is calculated. In the first formula, The average value of the first charge. The state of charge value of the main package, For the first The state of charge value of the packet, For the number of packages, The sum of the state of charge values ​​of all packets. .

[0067] Step S33: Determine the total amount of charge loss for all charge-loss units based on the sum of the differences between the state of charge value and the first average charge value of each charge-loss unit.

[0068] Step S34: Determine the total charge capacity of all charging packages based on the sum of the differences between the state of charge value of each charging package and the first average charge value.

[0069] In this step, a depleted battery is a slave battery whose state of charge (SOC) value is less than or equal to the first average SOC value, and a fully charged battery is a slave battery whose SOC value is greater than the first average SOC value.

[0070] For example, in this embodiment of the application, the state of charge value of each slave pack is compared with the first average charge value to determine that the slave pack with a state of charge value less than or equal to the first average charge value is a low-charge pack, and the slave pack with a state of charge value greater than the first average charge value is a high-charge pack.

[0071] For example, for the first From the package, the first The state of charge value of each packet With the average value of the first charge Comparison. When At that time, determine the first The first sub-packet is a low-power pack, and it is determined that the first sub-packet is a low-power pack. The state of charge value of each depleted battery is .when At that time, determine the first The package is a Yingdian package, and the first one is determined to be a Yingdian package. The state of charge value of the power supply package is .

[0072] In this embodiment, the difference between the state of charge value of each power-deficient unit and the first average charge value is calculated, and the differences between the state of charge values ​​of all power-deficient units and the first average charge value are summed to obtain the total power deficit of all power-deficient units (i.e., the sum of the differences between the state of charge value of each power-deficient unit and the first average charge value).

[0073] For example, according to the following formula: The total power deficit is calculated using the formula. For the total power loss, The average value of the first charge. For the first The state of charge value of a depleted battery. It is the sum of the differences between the state of charge values ​​of all depleted cells and the first average charge value.

[0074] In this embodiment, the difference between the state of charge value of each power pack and the first average charge value is calculated, and the differences between the state of charge values ​​of all power packs and the first average charge value are summed to obtain the total power capacity of all power packs (i.e., the sum of the differences between the state of charge value of each power pack and the first average charge value).

[0075] For example, according to the following formula: The total surplus power is calculated in the formula. For the total surplus power, The average value of the first charge. For the first The state of charge value of an individual battery pack. It is the sum of the differences between the state of charge values ​​of all charged cells and the first average charge value.

[0076] It is understandable that after calculating the difference between the state of charge value of the depleted or surplus battery and the first average charge value, the absolute value of the difference is used to sum the values ​​to obtain a positive total depleted or surplus charge.

[0077] Step S35: When the total power deficit is less than or equal to the state of charge of the main battery pack, charge and discharge operations are performed between multiple battery packs based on the total power deficit and the state of charge of each battery pack to achieve energy balance.

[0078] In this embodiment, the state of charge (SBC) value of the main packet is used to characterize the remaining electrical capacity currently available for output by the main packet. The total depleted capacity is used to characterize the total energy required to compensate all depleted packets to reach the first average charge value.

[0079] For example, in response to the total power deficit being less than or equal to the state of charge value of the main package (i.e. This confirms that the main contractor has the capacity to provide compensating energy to all power-deficient units, meaning that the main contractor can meet the energy compensation needs of all power-deficient units.

[0080] The target compensation amount for each power-deficient unit is determined based on the difference between its state of charge (SOC) value and the first average SOC value. For any power-deficient unit, the target compensation amount is positively correlated with the difference between the first average SOC value and the SOC value of that unit. Specifically, the greater the degree of power deficiency in a power-deficient unit (i.e., the difference between the first average SOC value and the SOC value of that unit), the greater the target compensation amount for that unit.

[0081] Based on the target compensation amount for each power-deficient unit, discharge control commands corresponding to the main unit and charging control commands corresponding to each power-deficient unit are generated. The discharge control commands control the main unit to output electrical energy to the balancing bus, and the charging control commands control the corresponding power-deficient unit to absorb electrical energy from the balancing bus. For example, in this embodiment, the energy balancing path between the main unit and the power-deficient units is controlled to be open, the main unit performs a discharge operation, and the power-deficient units simultaneously perform a charging operation. During the charging and discharging process, the main unit acts as the energy output terminal, the power-deficient units act as the energy receiving terminal, and the energy balancing path performs energy transfer.

[0082] In some embodiments, a balancing priority queue is generated based on the degree of power depletion of each power-depleted packet. The greater the degree of power depletion of a power-depleted packet, the higher its balancing priority. The main packet output energy is allocated sequentially according to the balancing priority queue; that is, energy is preferentially transferred to higher-priority power-depleted packets, then to the next lower-priority power-depleted packets, and so on, until finally energy is transferred to the lowest-priority power-depleted packet.

[0083] In some implementations, the embodiments of this application, through steps S351 to S353, perform charging and discharging operations between multiple battery packs based on the total power deficit and the state of charge value of each battery pack to achieve energy balance.

[0084] Step S351: Based on the difference between the first average charge value and the state of charge value of each depleted charge pack, determine the first target charging amount for each depleted charge pack.

[0085] Step S352: Use the main package to charge each depleted battery pack, and the charging amount of each depleted battery pack is the first target charging amount of that depleted battery pack, so that all depleted battery packs are charged to the first average charge value.

[0086] Step S353: Charge the main pack using all the charged packs to equalize the energy of the main pack to the second average charge value.

[0087] In this embodiment, the second average charge value is determined based on the state of charge value of the main package after discharge and the state of charge values ​​of all charged packages.

[0088] In step S351, the first target charging amount for each depleted battery is the difference between the first average charge value and the state of charge value of that depleted battery. That is: for the first... Each depleted battery will average the first charge. Subtract the first State of charge value of each depleted battery , obtained the The first target charging amount for a depleted battery ,Right now: .

[0089] In step S352, the energy balancing path between the main battery and each depleted battery is activated, allowing the main battery to charge each depleted battery. The amount of charge the main battery provides to each depleted battery is the first target charge amount for that depleted battery, thereby charging all depleted batteries to the first average charge value. .

[0090] In step S353, after charging each depleted battery pack using the main battery pack to charge all depleted battery packs to the first average charge value, the state of charge (SOC) value of the main battery pack after discharge is obtained. The average SOC value of the main battery pack after discharge and the average SOC values ​​of all charged battery packs are then calculated to obtain the second average charge value. Finally, the main battery pack is charged using all charged battery packs to balance the energy of the main battery pack to the second average charge value. It can be understood that after the energy of the main battery pack is balanced to the second average charge value, the SOC values ​​of all charged battery packs will also discharge to the second average charge value.

[0091] In some embodiments, the present application implements charging operations on the main pack using all the battery packs through steps S3531 to S3534, so that the energy of the main pack is balanced to the second average charge value.

[0092] Step S3531: Determine the second average charge value based on the state of charge value of the main package after discharge and the average state of charge value of all charged packages.

[0093] Step S3532: Based on the difference between the second average charge value and the state of charge value of the main pack after discharge, determine the total amount of charge to be charged in the main pack.

[0094] Step S3533: Determine the first target discharge amount for each battery pack based on the product of the total charging amount and the first discharge weight of each battery pack.

[0095] Step S3534: Charge the main pack using each battery pack and the discharge amount of each battery pack is the first target discharge amount of that battery pack, so that the main pack is charged to the second average charge value.

[0096] The first discharge weight of each battery pack is the ratio of its state of charge value to its first total charge, which is the sum of the state of charge values ​​of all battery packs.

[0097] For example, the sum of the state of charge values ​​of all charged cells is obtained to get the first total charge. For any charged cell, the ratio of the state of charge value of that charged cell to the first total charge is calculated to obtain the first discharge weight of that charged cell.

[0098] For the In this application embodiment, the following formula is used for the PC package: , Calculate the first The first discharge weight of the individual battery pack is given by the formula. For the first The first discharge weight of the battery pack For the first The state of charge value of an individual battery pack. This is the first total charge (i.e., the sum of the state of charge values ​​of all capacitor banks). The quantity of the power supply package.

[0099] In step S3531, the state of charge value of the main package after discharge and the average of the state of charge values ​​of all charged packages are obtained to obtain the second average charge value.

[0100] For example, according to the following formula: Calculate the average value of the second charge, in the formula, The second average charge value, This represents the state of charge (SOC) value of the main package after discharge. For the number of Yingdian packages, For the first The state of charge value of each battery pack.

[0101] In step S3532, the difference between the second average charge value and the state of charge value of the main pack after discharge is calculated to obtain the total amount of charge to be charged in the main pack (i.e., the energy output from all charged packs to the main pack).

[0102] For example, according to the following formula: Calculate the total amount of charge to be applied to the main package. The total amount of charge to be charged for the main package. The second average charge value, This represents the state of charge (SOC) value of the main package after discharge.

[0103] In step S3533, for any charged battery, the product of the total charging amount and the first discharge weight of the charged battery is determined as the first target discharge amount of the charged battery.

[0104] For example, for the first For each Yingdian package, the following formula applies: Calculate the first The first target discharge amount for the battery pack. For the first The first target discharge amount for the battery pack. Total charging amount For the first The first discharge weight of each Yingcheng Electric Packet.

[0105] In step S3534, the energy balancing path between each battery pack and the main pack is controlled to be connected, so that each battery pack charges the main pack, and the discharge amount of each battery pack is the first target discharge amount of the battery pack, so that the main pack is charged to the second average charge value, and all battery packs are discharged to the second average charge value.

[0106] Step S36: When the total power deficit is greater than the state of charge of the main battery pack, charge and discharge operations are performed between multiple battery packs based on the total power surplus and the state of charge of each battery pack to achieve energy balance.

[0107] For example, in response to the total power deficit being greater than the state of charge value of the main package (i.e. It was determined that the main package could not independently meet the energy compensation needs of all the power-deficient packages, and there was an energy gap.

[0108] Based on the total power deficit and the state of charge (SBC) value of the main unit, the energy gap to be compensated is determined. The energy gap to be compensated is the difference between the total power deficit and the SBC value. This energy gap characterizes the additional compensation energy that needs to be provided by the PCB.

[0109] The energy that a battery pack can provide is determined by the difference between its state of charge (SOC) value and a first average SOC value. For any battery pack, the greater the degree of charge (i.e., the difference between the SOC value and the first average SOC value), the greater the energy that the battery pack can provide.

[0110] Based on the available energy of all battery packs, the energy supply weight of each battery pack is determined. For example, the proportion of the available energy of each battery pack to the total battery capacity is determined as the energy supply weight of each battery pack. The higher the energy supply weight of a battery pack, the more discharge energy it can handle.

[0111] Based on the power supply weight of each power supply package and the energy gap to be compensated, the target power supply of each power supply package is determined. That is, the energy gap to be compensated is multiplied by the power supply weight of each power supply package to obtain the target power supply of each power supply package.

[0112] The target compensation amount for each power-deficient unit is determined based on the difference between the state of charge value of each unit and the first average charge value.

[0113] Based on the target energy supply and target compensation, an energy allocation relationship is established among the surplus power supply unit, the main power supply unit, and the deficit power supply unit. The surplus power supply unit acts as the first energy supply node, transmitting energy to the main power supply unit. The main power supply unit, as the first energy supply node, transmits energy to the deficit power supply unit, and simultaneously acts as the first energy receiver node, receiving energy transmitted from the surplus power supply unit. The deficit power supply unit acts as the second energy receiver node, receiving energy transmitted from the main power supply unit.

[0114] Based on the energy distribution relationship, charging control commands and discharging control commands are generated, and discharging control commands are sent to the main battery and the battery with full charge, while charging control commands are sent to the main battery and the battery with low charge, so that the main battery and the battery with full charge perform discharging operations, and the main battery and the battery with low charge perform charging operations.

[0115] In this embodiment, the equalization control process is repeatedly executed until any equalization control termination condition is met, at which point the energy equalization operation on the battery pack is stopped. The equalization control termination conditions include, but are not limited to, the differences between each slave pack and the first average charge value being less than an equalization threshold, the total charge deficit being less than a preset termination threshold, or the maximum value among the differences between each slave pack and the first average charge value being less than a preset difference threshold.

[0116] In some implementations, the embodiments of this application, through steps S361 to S364, perform charging and discharging operations between multiple battery packs based on the total surplus capacity and the state of charge value of each battery pack to achieve energy balance.

[0117] Step S361: Subtract the state of charge value of the main pack from the state of charge value corresponding to the full charge value to obtain the maximum chargeable amount of the main pack.

[0118] Step S362: Determine the second target discharge amount for each battery pack based on the maximum charge amount, total charge amount, and state of charge value of each battery pack.

[0119] The full charge value corresponds to a state of charge of 100%. It can be understood that the main pack can only be charged up to a state of charge of 100%, so it is necessary to calculate the maximum charging amount that the main pack can withstand (i.e., the maximum charging amount).

[0120] For example, the embodiments of this application are based on the formula: Calculate the maximum chargeable amount of the main package, where, The maximum amount of charge that the main package can hold. This represents the state of charge (i.e., 100%) corresponding to a full charge value. The state of charge value of the main package.

[0121] For example, after calculating the maximum chargeable amount of the main package, based on the maximum chargeable amount... With total power The size relationship is used to determine whether the main package can receive the total charge of all the charge packets, and the second target discharge amount of each charge packet is determined based on the result of whether the main package can receive the total charge of all the charge packets.

[0122] In some embodiments, the present application embodiments, through steps S3621 to S3622, determine the second target discharge amount of each battery pack based on the maximum charging amount, the total charge capacity, and the state of charge value of each battery pack.

[0123] Step S3621: In response to the maximum charging amount being greater than or equal to the total charge capacity, determine the second target discharge amount for each charge pack as the difference between the state of charge value of the charge pack and the first average charge value.

[0124] For example, when the maximum charging capacity is greater than or equal to the total available capacity, that is: This indicates that the main package can receive the total charge of all the charged packages. For any charged package, the difference between the state of charge value of that charged package and the first average charge value is determined as the second target discharge amount of that charged package.

[0125] For example, for the first In this application embodiment, the following formula is used for the PC package: Calculate the first The second target discharge amount for the battery pack. For the first The second target discharge amount for the battery pack. For the first The state of charge value of an individual battery pack. This is the average value of the first charge.

[0126] Understandably, in this scenario, after all the battery packs discharge (i.e., the main pack is charged using each battery pack as described below, and the discharge amount of each battery pack is the second target discharge amount of that battery pack), the state of charge value of all battery packs is the first average charge value.

[0127] Step S3622: In response to the maximum charging amount being less than the total charge capacity, determine the second target discharge amount for each charge pack as the product of the second discharge weight of each charge pack and the maximum charging amount.

[0128] The second discharge weight for each battery pack is the ratio of its state of charge (SOC) value to the second total charge, which is the sum of the SOC values ​​of all battery packs. In other words, the second total charge is obtained by summing the SOC values ​​of all battery packs. For any given battery pack, the ratio of its SOC value to the second total charge is calculated to obtain its second discharge weight.

[0129] For the In this application embodiment, the following formula is used for the PC package: , Calculate the first The second discharge weight of the battery pack For the first The second discharge weight of the battery pack For the first The state of charge value of an individual battery pack. The second total charge (i.e., the sum of the state of charge values ​​of all capacitor banks, plus the first total charge) is the sum of the first total charge values. same), The quantity of the power supply package.

[0130] For example, when the maximum charging capacity is less than the total available capacity, that is: This indicates that the main package cannot receive the total charge capacity of all the charge packages. For any charge package, the product of the maximum charge capacity and the second discharge weight of that charge package is determined as the second target discharge capacity of that charge package.

[0131] For example, for the first In this application embodiment, the following formula is used for the PC package: Calculate the first The second target discharge amount for the battery pack. For the first The second target discharge amount for the battery pack. For maximum charging capacity, For the first The second discharge weight of the ICBC battery.

[0132] Step S363: Charge the main pack using each battery pack and the discharge amount of each battery pack is the second target discharge amount of that battery pack, so that the main pack is charged to the state of charge value corresponding to the full charge value.

[0133] For example, the energy balancing path between each power pack and the main pack is controlled to be connected, so that each power pack charges the main pack, and the discharge amount of each power pack is the second target discharge amount of the power pack, so that the main pack is charged to the state of charge value corresponding to the full charge value (i.e., the main pack is charged to the state of charge value of 100%).

[0134] Step S364: Use the charged main pack to charge all the depleted packs so that the energy of the main pack is balanced to the third average charge value and all the depleted packs are charged to the third average charge value.

[0135] In this embodiment, the third average charge value is determined based on the state of charge (SOC) value of the main battery pack after charging and the SOC values ​​of all depleted batteries. That is, the average SOC value of the main battery pack after charging and the SOC values ​​of all depleted batteries are calculated to obtain the third average charge value.

[0136] For example, in this embodiment of the application, the energy balancing path between the main battery pack and all depleted battery packs is connected. The charged main battery pack is used to charge all depleted battery packs, so that the energy of the main battery pack is balanced to the third average charge value and all depleted battery packs are charged to the third average charge value. The charging amount for each depleted battery pack is the difference between the state of charge value of that battery pack and the third average charge value.

[0137] In some embodiments, the present application implements steps S3641 to S3644 to charge all depleted batteries using the charged main battery, so that the energy of the main battery is balanced to the third average charge value and all depleted batteries are charged to the third average charge value.

[0138] Step S3641: Determine the third average charge value based on the state of charge value of the main pack after charging and the average state of charge values ​​of all depleted packs.

[0139] Step S3642: Determine the total discharge amount of the main pack to be discharged based on the difference between the state of charge value of the main pack after charging and the third average charge value.

[0140] Step S3643: Determine the second target charging amount for each depleted battery based on the product of the total discharge amount and the charging weight of each depleted battery.

[0141] Step S3644: Use the charged main pack to charge each depleted pack, and the charging amount of each depleted pack is the second target charging amount of that depleted pack, so that the energy of the main pack is balanced to the third average charge value and all depleted packs are charged to the third average charge value.

[0142] The charging weight of each depleted battery pack is inversely proportional to its state of charge value.

[0143] In step S3641, the state of charge value of the main pack after charging and the average of the state of charge values ​​of all depleted packs are calculated to obtain the third average state of charge value.

[0144] For example, according to the formula: Calculate the average value of the third charge, where, The average of the third charge. This refers to the state of charge (SOC) value of the main pack after charging. For the number of power-loss units, For the first The state of charge value of each depleted battery.

[0145] In step S3642, the difference between the state of charge value of the main pack after charging and the third average charge value is calculated to obtain the total discharge amount of the main pack to be discharged (i.e. the energy of the main pack being discharged to all depleted packs).

[0146] For example, the embodiments of this application are based on the formula: Calculate the total discharge amount of the main package to be discharged, where, The total discharge amount to be discharged from the main package. This refers to the state of charge (SOC) value of the main pack after charging. This is the average value of the third charge.

[0147] In step S3643, for any depleted battery pack, the product of the total discharge amount and the charging weight of that depleted battery pack is determined as the second target charging amount of that depleted battery pack.

[0148] For example, for the first For a single power-depleted battery, the embodiment of this application is based on the formula: Calculate the first The second target charging amount for a depleted battery pack is given in the formula. For the first The second target charging amount for a depleted battery pack. The total discharge amount to be discharged from the main package. For the first The charging weight of each depleted battery pack.

[0149] In step S3644, the energy balancing path between the main pack and each depleted pack is connected, so that the charged main pack charges each depleted pack and the charging amount of each depleted pack is the second target charging amount of that depleted pack, so that the main pack is charged to the third average charge value, and all depleted packs are charged to the third average charge value.

[0150] See Figure 5 As shown, the battery pack energy balance control method provided in this application embodiment further includes steps S41 to S42.

[0151] Step S41: Sort all the depleted packets according to the order of their state of charge values ​​from smallest to largest to obtain the packet sequence.

[0152] Step S42: Determine the first packet from the packet sequence The ratio of the state of charge of the first depleted battery to the total charge of the third battery is the first The charging weight of each depleted battery pack.

[0153] In the embodiments of this application, ,in This represents the number of battery cells with low power. The third total power is the sum of the state of charge (SOC) values ​​of all battery cells with low power. That is, the third total power is obtained by summing the SOC values ​​of all battery cells with low power.

[0154] For example, according to the formula: Calculate the third total electricity consumption. This is the third largest total power consumption. For the number of power-loss units, For the first The state of charge value of each depleted battery.

[0155] The packet sequence comprises multiple depleted packets arranged in ascending order of their state of charge values. For example, regarding the first packet in the packet sequence... The first power-deficient unit, in this embodiment of the application, is calculated to be the first... The ratio of the state of charge of the first depleted battery to the total charge of the third battery, and the first... The ratio of the state of charge (SOC) of the first depleted battery to the total charge of the third battery is determined as the first SOC. The charging weight of each depleted battery pack.

[0156] For example, for the first For each battery pack with a low power output, according to the formula: Calculate the first The charging weight of a depleted battery pack. For the first The charging weight of a depleted battery pack. This is the third largest total power consumption. For the first The state of charge value of each depleted battery.

[0157] See Figure 6 As shown in the embodiment of this application, after determining the first target charging amount or the second target charging amount of the depleted battery pack, the provided battery pack energy balancing control method further includes steps S51 to S53.

[0158] Step S51: During each charging process of the depleted battery pack, determine the balancing time for each depleted battery pack based on the number of depleted battery packs and the reference depletion difference.

[0159] In this embodiment, the reference power deficit difference is the difference between the minimum value of the state of charge (SCC) of all power-deficient units and the first average SCC or the third average SCC, i.e., when the total power deficit is less than or equal to the SCC of the main unit (i.e.: In the case of ), the reference charge difference is the difference between the minimum value of the state of charge values ​​of all charge-deficient cells and the first average charge value, that is: , The average value of the first charge. The minimum value of the state of charge (SOC) of all depleted cells. For reference, the difference in power loss; when the total power loss is greater than the state of charge value of the main package (i.e.: In the case of ), the reference charge difference is the difference between the minimum state of charge value of all charge-deficient cells and the third average charge value, that is: , This is the average value of the third charge.

[0160] For example, in this embodiment of the application, the balancing time for each power-deficient pack is determined based on the number of power-deficient packs and a reference power deficit value. Specifically, when the number of power-deficient packs is large, the balancing time for each pack is shortened, the alternating charging frequency of the packs is increased, and the consistency of the rise in the state of charge value of the packs is improved. When the number of power-deficient packs is small, the balancing time for each pack is extended, the number of energy balancing path switching operations is reduced, energy consumption is lowered, and a dynamic balance between balancing efficiency and energy consumption is achieved.

[0161] In some implementations, the embodiments of this application determine the balancing time of each power-loss pack based on the number of power-loss packs and the reference power-loss difference through steps S511 to S512.

[0162] Step S511: Obtain the alternation ratio based on the ratio of the reference power loss difference to the number of power loss packs.

[0163] Step S512: Obtain the equilibrium duration based on the product of the preset proportional coefficient and the alternation ratio.

[0164] In step S511, the number of power-deficient packages is counted, and the ratio of the reference power deficit difference to the number of power-deficient packages is calculated to obtain the alternation ratio.

[0165] In step S512, the product of the preset proportional coefficient and the alternation ratio is determined as the balancing time for each power-deficient pack.

[0166] For example, for the first For each battery pack with a low power output, according to the second formula: Calculate the first The balancing time of each power-deficient unit. In the second formula, For the first The balancing time of a power-deficient battery pack. This is the proportionality coefficient. For reference, the difference in power loss, This refers to the number of batteries with insufficient power.

[0167] Understandably, after each charging of a depleted battery pack, the state of charge (SOC) value of that charged pack is no longer the minimum among all depleted packs. Therefore, the reference depletion difference will be updated, and the balancing time of the depleted pack will also be updated. The next time charging is performed, the master pack will be used to charge the depleted pack with the minimum SOC value using the updated balancing time.

[0168] Step S52: Sort the state of charge values ​​of all depleted cells from smallest to largest to obtain the charging priority of all depleted cells. The depleted cell with the smaller the state of charge value has the higher the charging priority.

[0169] Understandably, battery packs with lower energy (state of charge) are charged first, so that they can be charged as early as possible to increase their power supply.

[0170] Step S53: Control all depleted cells to alternately charge according to the equalization time and charging priority of each depleted cell.

[0171] In this embodiment, after determining the first target charging amount for each depleted battery pack, a first charging process is performed: charging each depleted battery pack according to the first target charging amount; after determining the second target charging amount for each depleted battery pack, a second charging process is performed: charging each depleted battery pack according to the second target charging amount. During either the first or second charging process, segmented alternating charging is performed according to the aforementioned determined charging priority.

[0172] For example, if there exists A power-loss battery pack, after determining the... The first target charging amount for the depleted battery and the After prioritizing the charging of each depleted battery pack, the battery packs are sorted by charging priority level as follows: , ... Among them, battery pack , ... The equilibrium durations are respectively , ... The battery pack is then subjected to a segmented, alternating charging process as described below, according to the aforementioned determined charging priority.

[0173] First alternating charging process: First, charge the battery pack with the highest charging priority. Charging equalization time Then charge the battery pack with the second charging priority. Charging equalization time And so on, ... and so on, for the th Battery pack with charging priority Charging equalization time Second alternating charging process: The charging priority is re-determined for the depleted battery packs after the first alternating charging process, and the charging priority is adjusted for the battery packs with the first charging priority. Charging equalization time Then charge the battery pack with the second charging priority. Charging equalization time And so on, ... and so on, until the 1st Battery pack with charging priority Charging equalization time The charging process is carried out in a fragmented and alternating manner for each depleted battery pack. It is worth noting that during the fragmented alternating charging process, if one depleted battery pack is fully charged before the others, the first fully charged depleted battery pack will exit the fragmented alternating charging process.

[0174] Overall, the embodiments of this application have at least the following beneficial effects.

[0175] First, it achieves rapid capture and response to sudden SOC imbalances. This application's embodiments employ a dynamic polling mechanism based on SOC and SOC change rate, enabling polling and data collection at corresponding frequencies for battery packs with different SOCs and SOC change rates. In particular, battery packs in an undervoltage state or experiencing drastic fluctuations in state of charge can trigger high-frequency polling. Therefore, it alleviates or avoids the SOC balancing lag caused by fixed-sequence or fixed-period polling, improving the response speed to sudden SOC imbalances by more than three times. It can quickly identify and prioritize the handling of battery packs in an undervoltage state or experiencing drastic fluctuations in state of charge.

[0176] Secondly, it achieves alternating changes and coordinated convergence of the State of Charge (SOC) of multiple battery packs. This application employs a time-sharing alternating charging strategy. Within each balancing period, the battery pack with the lowest SOC at that moment is selected for charging. After the balancing period ends, the packs are reordered and the charging targets are switched. This alleviates or avoids the inconsistent SOC rise rate caused by the "one-to-one full charging before switching to the next battery pack" mode. The SOC of multiple depleted battery packs exhibits an alternating upward trend, ultimately reaching the expected SOC almost simultaneously. The total balancing time is shortened by 30%-50%. No new imbalances arise during the energy balancing process due to a fixed charging sequence, dynamically and efficiently balancing the energy of the battery packs.

[0177] Third, it achieves priority equalization of undervoltage battery packs (i.e., battery packs in an undervoltage state). This application's embodiments employ an undervoltage priority equalization strategy, marking battery packs with a SOC below the undervoltage charging threshold as having the highest priority. These packs are equalized preferentially during alternating charging cycles. Newly emerging undervoltage battery packs can dynamically jump the queue to the next equalization period, avoiding situations where undervoltage battery packs have to wait in line and remain in the danger zone for extended periods. This effectively prevents capacity degradation and safety hazards caused by prolonged undervoltage.

[0178] This application provides a computer-readable storage medium storing processor-executable computer program instructions. When executed by a processor, the computer program instructions cause the processor to perform the battery pack energy equalization control method provided in this application or to perform the steps in any possible implementation of the battery pack energy equalization control method provided in this application.

[0179] In some embodiments, the storage medium may be a flash memory, a hard disk, an optical disk, a register, a magnetic surface memory, a removable disk, a CD-ROM, a random access memory (RAM), a read-only memory (ROM), an electrically programmable ROM, and an electrically erasable programmable ROM, or any other form of storage medium known in the art, or various devices including one or any combination of the above storage media.

[0180] In some embodiments, computer program instructions may take the form of programs, software, software modules, scripts, or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as stand-alone programs or as modules, components, subroutines, or other units suitable for use in a computing environment.

[0181] As an example, computer program instructions may, but do not necessarily, correspond to files in a file system, and may be stored as part of a file that holds other programs or data, for example, in one or more scripts in an HTML (Hypertext Markup Language) document, or in a single file dedicated to the program in question, or in multiple collaborative files (e.g., a file that stores one or more modules, subroutines, or code sections).

[0182] As an example, computer program instructions can be deployed to execute on a single computing device (including devices such as smart terminals and servers), or on multiple computing devices located in one location, or on multiple computing devices distributed across multiple locations and interconnected via a communication network. It is readily understood that all or part of the steps of the methods described in the embodiments provided above can be implemented directly using electronic hardware or processor-executable computer program instructions, or a combination of both.

[0183] Those skilled in the art will understand that the embodiments provided in this application are merely illustrative. The order in which the steps in the methods of the embodiments are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The order can be adjusted, merged, and deleted according to actual needs. Modules or sub-modules, units or sub-units in the apparatus or system of the embodiments can be merged, divided, and deleted according to actual needs. For example, the division of units is only a logical functional division, and there may be other division methods in actual implementation. For another example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0184] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, and of course, it can also be implemented using hardware. Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This computer program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. It should be understood that the storage medium can be flash memory, hard disk, optical disk, register, magnetic surface memory, removable disk, CD-ROM, random access memory (RAM), read-only memory (ROM), electrically programmable ROM, and electrically erasable programmable ROM, etc.

[0185] It should be noted that the above embodiments are for illustrating the technical concept and features of this application, and are intended to enable those skilled in the art to understand the content of this application and implement it accordingly. They should not be construed as limiting the scope of protection of this application. Those skilled in the art can understand that all or part of the processes of the above embodiments can be implemented, modified according to the technical solutions described in the embodiments of this application, or equivalent substitutions can be made to some of the technical features. It is understood that these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and should be considered as equivalent changes and modifications made based on the embodiments of this application, all of which should fall within the scope of the claims of this application.

Claims

1. A battery pack energy balancing control method for balancing the energy among multiple battery packs, characterized in that, The plurality of battery packs are divided into a main pack and at least one slave pack, and the energy balancing control method includes: During the energy balance control process, the polling frequency of collecting data for each battery pack is determined based on the state of charge value and the rate of change of state of charge of each battery pack at preset time intervals. The first average charge value is determined based on the average state of charge value of all the battery packs collected during the round-robin survey. The total amount of charge loss of all the depleted packages is determined based on the sum of the differences between the state of charge value of each depleted package and the first average charge value. The depleted package is a slave package whose state of charge value is less than or equal to the first average charge value. The total charge capacity of all the charging packages is determined based on the sum of the differences between the state of charge value of each charging package and the first average charge value. The charging package is a slave package whose state of charge value is greater than the first average charge value. When the total power deficit is less than or equal to the state of charge value of the main battery pack, charging and discharging operations are performed between multiple battery packs based on the total power deficit and the state of charge value of each battery pack to achieve energy balance. When the total power deficit is greater than the state of charge (SOC) of the main battery pack, charging and discharging operations are performed between the multiple battery packs based on the total power surplus and the SOC of each battery pack to achieve energy balance.

2. The energy balance control method according to claim 1, characterized in that, The step of performing charge and discharge operations among multiple battery packs to achieve energy balance based on the total power deficit and the state of charge value of each battery pack includes: Based on the difference between the first average charge value and the state of charge value of each of the depleted charge packs, a first target charging amount is determined for each of the depleted charge packs; The main package is used to charge each of the depleted batteries, and the charging amount of each depleted battery is the first target charging amount of that depleted battery, so that all the depleted batteries are charged to the first average charge value. The main pack is charged using all of the charged packs to equalize the energy of the main pack to a second average charge value, which is determined based on the state of charge of the main pack after discharge and the state of charge of all the charged packs.

3. The energy balance control method according to claim 2, characterized in that, The step of charging the main pack using all the charged cells to balance the energy of the main pack to a second average charge value includes: The second average charge value is determined based on the state of charge value of the main package after discharge and the average state of charge values ​​of all the charged packages. Based on the difference between the second average charge value and the state of charge value of the main package after discharge, the total amount of charging to be done for the main package is determined. The first target discharge amount of each battery pack is determined based on the product of the total charging amount and the first discharge weight of each battery pack. The main pack is charged using each of the charged packs, and the discharge amount of each charged pack is the first target discharge amount of that charged pack, so that the main pack is charged to the second average charge value; The first discharge weight of each of the charged cells is the ratio of the state of charge value of the charged cell to the first total charge, where the first total charge is the sum of the state of charge values ​​of all the charged cells.

4. The energy balance control method according to claim 1, characterized in that, The step of performing charge and discharge operations among multiple battery packs to achieve energy balance based on the total surplus capacity and the state of charge value of each battery pack includes: Subtracting the state of charge value of the main pack from the state of charge value corresponding to the full charge value yields the maximum chargeable amount of the main pack. The second target discharge amount for each of the charged cells is determined based on the maximum charging amount, the total charge capacity, and the state of charge value of each charged cell. The main pack is charged using each of the charged packs, and the discharge amount of each charged pack is the second target discharge amount of that charged pack, so that the main pack is charged to the state of charge value corresponding to the full charge value; The main pack, after being charged, is used to charge all the depleted packs, so that the energy of the main pack is balanced to a third average charge value and all the depleted packs are charged to the third average charge value, which is determined based on the state of charge value of the main pack after being charged and the state of charge values ​​of all the depleted packs.

5. The energy balance control method according to claim 4, characterized in that, The step of determining the second target discharge amount for each of the charged cells based on the maximum charging amount, the total charge capacity, and the state of charge value of each charged cell includes: In response to the maximum charging amount being greater than or equal to the total charge capacity, the second target discharge amount for each charge pack is determined to be the difference between the state of charge value of the charge pack and the first average charge value. In response to the maximum charging amount being less than the total charge capacity, a second target discharge amount for each charge pack is determined as the product of a second discharge weight for each charge pack and the maximum charging amount. The second discharge weight of each charged battery is the ratio of the state of charge value of the charged battery to the second total charge, whereby the second total charge is the sum of the state of charge values ​​of all charged batteries.

6. The energy balance control method according to claim 4, characterized in that, The step of using the charged main pack to charge all the depleted packs, so that the energy of the main pack is balanced to the third average charge value and all the depleted packs are charged to the third average charge value, includes: The third average charge value is determined based on the state of charge value of the main pack after charging and the average state of charge values ​​of all the depleted packs. The total discharge amount of the main package to be discharged is determined based on the difference between the state of charge value of the main package after charging and the third average charge value. The second target charging amount for each of the depleted batteries is determined based on the product of the total discharge amount and the charging weight of each depleted battery. The main pack after charging is used to charge each of the depleted packs, and the charging amount of each depleted pack is the second target charging amount of that depleted pack, so that the energy of the main pack is balanced to the third average charge value and all the depleted packs are charged to the third average charge value. The charging weight of each depleted battery pack is inversely proportional to its state of charge value.

7. The energy balance control method according to any one of claims 4-6, characterized in that, The method further includes: Based on the ascending order of the state of charge values, all the depleted packets are sorted to obtain the packet sequence; Determine the first from the packet sequence The ratio of the state of charge (SBC) of the depleted battery to the total charge is the first... The charging weight of the aforementioned depleted battery pack. , The number of the depleted battery packs is given, and the third total power is the sum of the state of charge values ​​of all the depleted battery packs.

8. The energy balance control method according to claim 1, characterized in that, The step of determining the polling frequency for collecting data from each battery pack during the energy balance control process, based on the state of charge (SOC) value and rate of change of SOC for each battery pack, includes: In response to the fact that the state of charge value of the slave packet is less than a preset state of charge threshold, a preset first frequency is determined as the polling frequency of the slave packet; In response to the state of charge value of the slave packet being greater than or equal to the state of charge threshold and the rate of change of the state of charge of the slave packet being greater than or equal to the preset state of charge change threshold, a preset second frequency is determined as the polling frequency of the slave packet. In response to the slave packet's state of charge value being greater than or equal to the state of charge threshold and the slave packet's rate of change of state of charge being less than the state of charge threshold, a preset third frequency is determined as the slave packet's polling frequency, wherein the first frequency is greater than the second frequency and the second frequency is greater than the third frequency.

9. The energy balance control method according to claim 2 or 6, characterized in that, After determining the first target charging amount or the second target charging amount for each of the depleted batteries, the energy balancing control method further includes: During each charging process of the depleted battery pack, the balancing time of each depleted battery pack is determined based on the number of depleted battery packs and the reference depletion difference. The reference depletion difference is the difference between the minimum value of the state of charge values ​​of all depleted battery packs and the first average value or the third average value of the state of charge. The state of charge (SOC) values ​​of all the depleted battery packs are sorted from smallest to largest to obtain the charging priority of all the depleted battery packs. The lower the SOC value, the higher the charging priority of the depleted battery pack. All the depleted battery packs are controlled to alternately charge according to the equalization time and charging priority of each depleted battery pack.

10. The energy balance control method according to claim 9, characterized in that, The step of determining the balancing duration for each power-deficient package based on the number of power-deficient packages and a reference power deficit value includes: An alternation ratio is obtained based on the ratio of the reference power deficit difference to the number of power deficit packs; The equilibrium duration is obtained by multiplying the preset proportional coefficient by the alternation ratio.

11. An energy balancing system, characterized in that, include: Multiple battery packs, including one master pack and at least one slave pack; An equalization controller includes at least one DAB converter, each of the DAB converters having one end connected to the master packet and the other end connected to a slave packet; A processor connected to the equalization controller, the processor being configured to perform the battery pack energy equalization control method according to any one of claims 1 to 10.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores processor-executable computer program instructions, which, when executed by the processor, cause the processor to perform the battery pack energy balancing control method as described in any one of claims 1 to 10.

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