Battery current sharing control method and system and electronic equipment

Abstract

The invention relates to the technical field of batteries, and discloses a battery current-sharing control method and system and electronic equipment, the battery current-sharing control method is applied to a clustered battery system, the clustered battery system comprises a plurality of battery clusters connected in parallel, and the method comprises the following steps: acquiring battery running state information of each battery cluster, the battery running state information comprises a working current limiting value and a rated capacity of the battery cluster; obtaining a working current sharing coefficient of each battery cluster according to the working current limiting value and the rated capacity of each battery cluster; and performing current sharing control on the working current of each battery cluster according to the working current sharing coefficient of each battery cluster. According to the invention, the problem that the current of each battery cluster is unbalanced is effectively improved, and the current-sharing control of each battery cluster connected in parallel is realized.

Description

Battery current sharing control methods, systems and electronic devices Technical Field

[0001] This invention relates to the field of battery technology, and more specifically to battery current sharing control methods, systems, and electronic devices. Background Technology

[0002] With the rapid development of the new energy industry, the demand for energy storage batteries is increasing. Against this backdrop, not only are individual batteries required to have higher energy density and longer cycle life, but also more stringent requirements are placed on the overall capacity, power output and stability of the energy storage system. Therefore, the use of multiple batteries in parallel has become an inevitable function in practical applications.

[0003] However, in related technologies, during the use of multiple battery clusters, due to the influence of various internal and external factors such as the internal resistance, state of charge (SOC), capacity, and line impedance of each battery cluster, there will be differences between the battery clusters. As the number of charge and discharge cycles of the battery clusters increases, as well as the influence of factors such as storage time and temperature, the battery clusters will be in an overcharged or over-discharged state for a long time. On the one hand, this will exacerbate the inconsistency of the battery clusters, and on the other hand, it will gradually lead to battery degradation. Ultimately, this will result in uneven current distribution among the battery clusters, thereby affecting battery safety. Summary of the Invention

[0004] This invention provides a battery current sharing control method, system, and electronic device, which aims to effectively improve the problem of uneven current distribution among battery clusters in parallel batteries in related technologies.

[0005] In a first aspect, the present invention provides a battery current sharing control method applied to a parallel battery system, the parallel battery system comprising multiple parallel battery clusters, the battery current sharing control method comprising: acquiring battery operating status information of each battery cluster, the battery operating status information including the operating current limit value and rated capacity of the battery cluster; acquiring the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster; and performing current sharing control on the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster.

[0006] In some optional embodiments, the tandem battery system further includes multiple battery management systems, each battery management system being connected to a battery cluster in a one-to-one correspondence. The step of obtaining the battery operating status information of each battery cluster includes: receiving the battery operating status information of each battery cluster fed back by each battery management system.

[0007] In some optional embodiments, obtaining the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster includes: determining the capacity ratio of each battery cluster based on the rated capacity of each battery cluster; determining the current limit value ratio of each battery cluster based on the operating current limit value of each battery cluster; and determining the operating current sharing coefficient of each battery cluster based on the product of the rated capacity ratio and the current limit value ratio of each battery cluster.

[0008] In some alternative implementations, the capacity percentage of the battery cluster is the ratio of the rated capacity of the battery cluster to the sum of the rated capacities of all the battery clusters.

[0009] In some optional implementations, the current limiting value of the battery cluster is the ratio of the operating current limiting value of the battery cluster to the sum of the operating current limiting values ​​of each battery cluster.

[0010] In some optional implementations, the step of controlling the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster includes: for each battery cluster, determining a first candidate current of the battery cluster based on the product of the operating current sharing coefficient of the battery cluster and the maximum operating current, wherein the maximum operating current is the current output from an external power source to the battery cluster or the current output from the battery cluster to a load; determining a target current corresponding to the battery cluster from the first candidate current and a second candidate current of the battery cluster, wherein the second candidate current is the current operating current limit value of the battery cluster; and controlling the operating current of the battery cluster to the corresponding target current.

[0011] In some optional embodiments, the parallel battery system further includes multiple current controllers, each connected to a battery cluster in a one-to-one correspondence, and controlling the operating current of the battery cell to the target current includes: controlling the operating current of the corresponding battery cluster to the corresponding target current through the current controller.

[0012] In some optional implementations, determining the target current corresponding to the battery cluster from the first candidate current and the second candidate current of the battery cluster includes: determining the minimum value of the first candidate current and the second candidate current as the target current corresponding to the battery cluster.

[0013] Secondly, the present invention provides a battery management system applied to a parallel battery system, the parallel battery system including the battery management system and multiple parallel battery clusters, the battery management system including: an acquisition unit for acquiring battery operating status information of each battery cluster, the battery operating status information including the operating current limit value and rated capacity of each battery cluster; a current sharing coefficient calculation unit for acquiring the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster; and a current sharing control unit for performing current sharing control on the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster.

[0014] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the battery current sharing control method of the first aspect or any corresponding embodiment described above.

[0015] According to the battery current sharing control method, system, and electronic device provided in the embodiments of the present invention, the current sharing coefficient of each battery cluster is calculated by obtaining the current limit value and rated capacity of each battery cluster, and the operating current of each battery cluster is adjusted based on the current sharing coefficient of each battery cluster. The current sharing coefficient of each battery cluster is controlled by the current sharing of each battery cluster. The calculation of the current sharing coefficient of the battery cluster does not depend on the SOC, actual capacity, or other factors of the battery cluster. The current balance control of each battery cluster is dynamically adapted to the changes in the battery operating state, which can help avoid the current imbalance caused by parameter lag and effectively improve the problem of current imbalance of each battery cluster, thus realizing the current sharing control of each battery cluster connected in parallel. Attached Figure Description

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

[0017] Figure 1 is a schematic diagram of an application scenario according to an embodiment of the present invention; Figure 2 is a flowchart of a battery current sharing control method according to an embodiment of the present invention; Figure 3 is a flowchart of a method for obtaining the working current sharing coefficient of a battery cluster according to an embodiment of the present invention; Figure 4 is a flowchart of a current sharing control method according to an embodiment of the present invention; Figure 5 is a structural block diagram of a battery management system according to an embodiment of the present invention; Figure 6 is a hardware structure diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0020] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] Figure 1 is a schematic diagram of an application scenario of an embodiment of the present invention. As an optional application scenario of the present invention, as shown in Figure 1, the parallel battery system includes multiple Battery Management Systems (BMS), multiple parallel battery clusters, and multiple current controllers. The multiple BMS include a first BMS, a second BMS, a third BMS, ..., an nth BMS, where n is the total number of BMS. The multiple BMS are connected to each other via CAN (Controller Area Network) lines, and each BMS is connected to a battery cluster in a one-to-one correspondence. The battery cluster includes a Battery Cluster Unit (BCU) and a battery pack or battery string composed of multiple independent battery modules connected in series. The current controller is connected in series with each battery cluster in a one-to-one correspondence. The battery cluster can be connected to the load through the corresponding current controller, and the current controller and the load can be connected through a power line. Each BMS can also be connected to the load through a CAN line.

[0022] In this system, one BMS can be selected from multiple BMSs as the system master, while the other BMSs act as system slaves. For example, the first BMS can be the system master, and the second, third, ..., nth BMS can be the system slaves.

[0023] As the host of the parallel battery system, the first BMS is responsible for overall system coordination and decision-making. The first BMS can collect data from its own corresponding battery cluster and data from other battery clusters collected by other BMSs in real time to obtain parameters such as voltage, current, and temperature of each battery cluster. When it detects abnormal conditions such as overvoltage, overcurrent, or overtemperature in a battery cluster, it can automatically cut off the charging and discharging circuit of the battery cluster to prevent battery damage or safety accidents. It can also adjust the charging and discharging current of each battery cluster to ensure the voltage consistency of each individual battery module in the battery cluster and extend battery life. It can use protocols such as CAN bus to interact with external devices (such as chargers and alarms) and supports remote monitoring and data storage.

[0024] The second, third, ..., and nth BMS, acting as slave units in the parallel battery system, are local monitoring units within the distributed BMS architecture. They are responsible for collecting and processing data from specific areas within their respective battery clusters. They can monitor the voltage, temperature, and other states of individual battery modules within their respective clusters, transmitting data to the first BMS (master) via low-speed communication (such as CAN). They possess basic overcurrent and overvoltage protection functions, supplementing the first BMS and improving system reliability. Under the command of the first BMS, they can perform equalization charging and discharging of local battery clusters, optimizing overall performance. The first BMS and other BMS work collaboratively to achieve comprehensive monitoring and management of the parallel battery clusters.

[0025] The current controller is connected to each battery cluster in a one-to-one correspondence, and is responsible for controlling and adjusting the current input to the corresponding battery cluster and the current output of the corresponding battery cluster.

[0026] In related technologies, during the use of multiple battery clusters, uneven current distribution can occur among the battery clusters due to various internal and external factors such as the internal resistance of each battery cluster, the state of charge (SOC) of the battery, capacity, and line impedance.

[0027] Therefore, embodiments of the present invention provide a battery current sharing control method, system, and electronic device, which aim to effectively improve the problem of uneven current distribution among battery clusters in parallel batteries in related technologies.

[0028] According to an embodiment of the present invention, a battery current sharing control method embodiment is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0029] This invention provides a battery current sharing control method, which can be used as the host battery management system (BMS) in the above-mentioned parallel battery system. The parallel battery system includes multiple parallel battery clusters. Figure 2 is a flowchart of a battery current sharing control method provided in this invention. As shown in Figure 2, the battery current sharing control method includes the following steps: Step S201, obtaining the battery operating status information of each battery cluster, including the working current limit value and rated capacity of the battery cluster.

[0030] Among them, the working current limit value refers to the charging and discharging current limit value of the battery cluster, including the charging current limit value and the discharging current limit value. The charging current limit value refers to the maximum charging current allowed for the battery cluster, and the discharging current limit value refers to the maximum discharging current allowed for the battery cluster.

[0031] Rated capacity is the total rated nominal capacity of a battery cluster, which is the amount of charge that the battery cluster can provide under specific conditions (such as temperature, discharge rate, etc.).

[0032] In this embodiment of the invention, the rated capacity of the battery cluster is a fixed value, and the operating current limit value of the battery cluster will change with the temperature and voltage of the battery cluster. Each battery management system (BMS) can monitor and read the current operating current limit value of its corresponding battery cluster in real time based on the voltage and temperature of its corresponding battery cluster and the characteristics of the battery cells.

[0033] In step S201, the battery operating status information of each battery cluster is obtained through the battery management system (BMS) corresponding to each battery cluster.

[0034] Step S202: Obtain the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster.

[0035] The operating current sharing coefficient is an indicator that measures the uniformity of the operating current distribution of each current cluster operating in parallel. The operating current sharing coefficient includes the charging current sharing coefficient and the discharging current sharing coefficient.

[0036] In this embodiment of the invention, the working current limit value of the battery cluster includes the charging current limit value, and the working current sharing coefficient includes the charging current sharing coefficient. In step S202, the charging current sharing coefficient of each battery cluster is obtained based on the current charging current limit value and rated capacity of each battery cluster. The working current limit value of the battery cluster includes the discharging current limit value, and the working current sharing coefficient includes the discharging current sharing coefficient. In step S202, the discharging current sharing coefficient of each battery cluster is obtained based on the current discharging current limit value and rated capacity of each battery cluster.

[0037] Step S203: Perform current sharing control on the operating current of each battery cluster according to the operating current sharing coefficient of each battery cluster.

[0038] The operating current of a battery cluster includes charging current and discharging current. Current sharing control refers to a control method that distributes the charging current or discharging current of each battery cluster connected in parallel as evenly as possible.

[0039] In this embodiment of the invention, the working current sharing coefficient of the battery cluster includes the charging current sharing coefficient, and the working current includes the charging current. In step S203, the charging current of each battery cluster is controlled by the charging current sharing coefficient. The working current sharing coefficient of the battery cluster includes the discharging current sharing coefficient, and the working current includes the discharging current. In step S203, the discharging current of each battery cluster is controlled by the discharging current sharing coefficient.

[0040] According to the battery current sharing control method provided in the embodiments of the present invention, the current sharing coefficient of each battery cluster is calculated by obtaining the current limit value and rated capacity of each battery cluster, and the operating current of each battery cluster is adjusted based on the current sharing coefficient of each battery cluster. The current sharing control of the operating current of each battery cluster is performed. The calculation of the current sharing coefficient of the battery cluster does not depend on factors such as the SOC and actual capacity of the battery cluster. The current balance control of each battery cluster is dynamically adapted to the changes in the battery operating state, which can help avoid the current imbalance caused by parameter lag, effectively improve the problem of current imbalance of each battery cluster, and realize the current sharing control of each battery cluster connected in parallel.

[0041] In some optional implementations, the tandem battery system also includes multiple battery management systems, each connected to a battery cluster in a one-to-one correspondence. In step S201 above, obtaining the battery operating status information of each battery cluster may include receiving the battery operating status information of each battery cluster fed back by each battery management system.

[0042] As shown in Figure 1, the battery current sharing control method of this embodiment of the invention is applied to the first BMS, which is the system host. The first BMS can directly collect the battery operating status information of its corresponding battery cluster and can receive the battery operating status information of other battery clusters reported by other battery management systems (the second BMS to the nth BMS).

[0043] In some optional implementations, the battery operating status information also includes the operating status of the battery cluster, the switching status of the operating control switch, SOC, battery current, etc. The operating status refers to the working state of the battery cluster, which may include the voltage output status of the battery cluster; the operating control switch refers to the charging control switch and discharging control switch of the battery cluster. The switch can be a MOSFET. The charging control switch is used to control the charging of the battery cluster, and the discharging control switch is used to control the discharging of the battery cluster.

[0044] In some optional implementations, after the parallel battery system is powered on, each battery management system, acting as a slave, registers with the battery management system, acting as the master, and obtains a corresponding communication address. The communication address of each battery management system is fixed and unique.

[0045] In some optional implementations, each battery management system acting as a slave can periodically or in real-time report the current battery operating status information of its corresponding battery cluster to the battery management system acting as the master via the CAN bus. The battery management system acting as the master receives the current battery operating status information of each battery cluster reported by each battery management system acting as a slave.

[0046] In some optional implementations, each battery management system (BMS) acting as a slave can, based on the voltage and temperature of its corresponding battery cluster and the characteristics of the battery cells, report the current battery operating status information of the battery cluster to the master BMS via the CAN bus when it detects a change in the operating current limit value of the battery cluster caused by a change in the temperature or voltage of the corresponding battery cluster. The master BMS receives the current battery operating status information of each battery cluster reported by each slave BMS. At the same time, the master BMS can, based on the voltage and temperature of its corresponding battery cluster and the characteristics of the battery cells, collect the current battery operating status information of its corresponding battery cluster when it detects a change in the operating current limit value of the battery cluster caused by a change in the temperature or voltage of its corresponding battery cluster.

[0047] In some optional implementations, the master battery management system can receive battery operating status information of each battery cluster reported by each slave battery management system in the order of their communication addresses.

[0048] In some optional implementations, after receiving the battery operating status information of each battery cluster, the battery management system, acting as the host, determines whether the battery cluster is working normally based on the battery operating status information; when it is determined that the battery cluster is in a normal working state, it performs subsequent current sharing coefficient calculation and current sharing control process for the battery cluster; when it is determined that the battery cluster is in an abnormal state, it does not perform any further processing on the battery cluster and waits for the battery cluster to return to a normal working state.

[0049] Specifically, when all operating control switches are in the ON state and the operating status indicates that the battery cluster is in a high-voltage output state, then the battery cluster is determined to be in a normal operating state.

[0050] If at least one working control switch is in the off state or the operating state is without high voltage output, the battery cluster is determined to be in an abnormal state.

[0051] Figure 3 is a flowchart illustrating a method for obtaining the working current sharing coefficient of a battery cluster in an embodiment of the present invention. In some optional embodiments, as shown in Figure 3, in step S202 above, obtaining the working current sharing coefficient of each battery cluster based on the working current limit value and rated capacity of each battery cluster may further include: step S301, determining the capacity ratio of each battery cluster based on the rated capacity of each battery cluster.

[0052] Wherein, the capacity percentage K_i of the battery cluster is the ratio of the rated capacity RatedCap_i of the battery cluster to the sum of the rated capacities RatedCap_j of all battery clusters, that is, K_i = RatedCap_i / ∑RatedCap_j, where K_i represents the capacity percentage of the i-th battery cluster, RatedCap_i represents the rated capacity of the i-th battery cluster, RatedCap_j represents the rated capacity of the j-th battery cluster, j = 1, 2, 3, ..., N, and N is the total number of battery clusters, i j.

[0053] Step S302: Determine the percentage of current limiting value for each battery cluster based on the operating current limiting value of each battery cluster.

[0054] Among them, the current limiting value of the battery cluster is the ratio of the working current limiting value of the battery cluster to the sum of the working current limiting values ​​of each battery cluster.

[0055] In some optional implementations, the operating current limit value includes the charging current limit value, and the current limit value percentage of the battery cluster includes the charging current limit value percentage, A of the charging current limit value of the battery cluster. Charge _i is the charging current limit value I for the battery cluster. ChargeLim The ratio of _i to the sum of the charging current limits of each battery cluster, i.e., A Charge _i=I ChargeLim_ i / (I ChargeLim_ 1+I ChargeLim _2+…+I ChargeLim _N); where I ChargeLim _i represents the charging current limit value of the i-th battery cluster, and N represents the total number of battery clusters.

[0056] In some optional implementations, the operating current limit value includes the discharge current limit value, and the current limit value percentage of the battery cluster includes the discharge current limit value percentage, where A is the discharge current limit value percentage of the battery cluster. DisCharge _i is the discharge current limit value I of the battery cluster. DisChargeLim The ratio of _i to the sum of the discharge current limits of each battery cluster, i.e., A DisCharge _i=I DisChargeLim_ i / (I DisChargeLim_ 1+I DisChargeLim _2+…+I DisChargeLim _N); where I DisChargeLim_i represents the discharge current limit value of the i-th battery cluster, and N represents the total number of battery clusters.

[0057] Step S303: Determine the operating current sharing coefficient of each battery cluster based on the product of the rated capacity ratio and the current limiting value ratio of each battery cluster.

[0058] The operating current sharing coefficient of the battery cluster is the product of the rated capacity ratio of the battery cluster and the current limiting value ratio.

[0059] In some optional implementations, the current limiting value percentage of the battery cluster includes the charging current limiting value percentage A. Charge _i, the operating current sharing coefficient of the battery cluster includes the charging current sharing coefficient R Charge _i, Charging current sharing coefficient R Charge _i represents the percentage of the rated capacity of the battery cluster K_i and the percentage of the charging current limiting value A. Charge The product of _i, i.e., R Charge _i=K_i×A Charge _i=K_i×I ChargeLim_ i / (I ChargeLim_ 1+I ChargeLim _2+…+I ChargeLim _N).

[0060] In some optional implementations, the current limiting value percentage of the battery cluster includes the discharge current limiting value percentage A. DisCharge _i, the operating current sharing coefficient of the battery cluster includes the discharge current sharing coefficient R DisCharge _i, discharge current sharing coefficient R DisCharge _i represents the percentage of the rated capacity of the battery cluster K_i and the percentage of the discharge current limiting value A. DisCharge The product of _i, i.e., R DisCharge _i=K_i×A DisCharge _i=I DisChargeLim_ i / (I DisChargeLim_ 1+I DisChargeLim _2+…+I DisChargeLim _N).

[0061] Figure 4 is a flowchart of a current sharing control method in an embodiment of the present invention. In some optional embodiments, as shown in Figure 4, in the above step S203, the current sharing control of the working current of each battery cluster is performed according to the working current sharing coefficient of each battery cluster, which may further include: step S401, for each battery cluster, the first candidate current of the battery cluster is determined according to the product of the working current sharing coefficient of the battery cluster and the maximum working current.

[0062] The maximum operating current is the maximum current output from the external power supply to the battery cluster or the maximum current that the battery cluster needs to output to the load. The first candidate current of the battery cluster is the product of the maximum operating current I and the operating current sharing coefficient.

[0063] In some alternative implementations, when the battery cluster needs to be charged, the operating current sharing coefficient is the charging current sharing coefficient R. Charge _i, the maximum operating current is the maximum current I1 output by the external power supply to the battery pack, and the first candidate current is the maximum operating current I1 plus the charging current sharing coefficient R. Charge The product of _i, i.e., I1×R Charge _i.

[0064] In some alternative implementations, when the battery cluster needs to discharge to an external load, the operating current sharing coefficient is equal to the discharge current sharing coefficient R. DisCharge _i, the maximum operating current is the maximum current I2 that the battery pack needs to output to the load, and the first candidate current is the maximum operating current I2 plus the discharge current sharing coefficient R. DisCharge The product of _i, i.e., I²×R DisCharge _i.

[0065] Step S402: Determine the target current corresponding to the battery cluster from the first candidate current and the second candidate current of the battery cluster. The second candidate current is the current operating current limit value of the battery cluster.

[0066] In some optional implementations, determining the target current corresponding to the battery cluster from the first candidate current and the second candidate current includes: determining the minimum value of the first candidate current and the second candidate current as the target current corresponding to the battery cluster.

[0067] Step S403: Control the operating current of the battery cluster to the corresponding target current.

[0068] In some optional embodiments, the tandem battery system also includes multiple current controllers, each connected to a battery cluster in a one-to-one correspondence. In step S403, controlling the operating current of the battery cluster to the target current includes: controlling the operating current of the corresponding battery cluster to the corresponding target current through the current controller.

[0069] Specifically, the target current corresponding to the battery cluster is sent to the current controller corresponding to the battery cluster. The current controller converts the target current into actual control action. By adjusting the duty cycle, the operating current of the corresponding battery cluster is adjusted, thereby controlling the operating current of the battery cluster to the corresponding target current, thus realizing closed-loop control of current sharing.

[0070] In some alternative implementations, the current controller may include a DC-DC converter.

[0071] In this embodiment of the invention, if any one or more battery management systems detect a change in the voltage or temperature of the corresponding battery cluster, resulting in an update of the charge / discharge current limit value, they will immediately upload the new charge / discharge current limit value to the battery management system acting as the host. The battery management system acting as the host will recalculate the charge / discharge current sharing coefficient and target current of the battery cluster to ensure that the current distribution of each battery cluster is dynamically adapted to the battery operating state of each battery cluster, avoiding the imbalance of current sharing caused by parameter lag, thereby ensuring that the entire parallel battery system can maximize its performance during the charge and discharge process.

[0072] In practical applications, the embodiments of the present invention do not rely on parameters such as SOC that require complex derivation, and do not require an optimizer. The current sharing coefficient is calculated only by the ratio of charge and discharge current limiting values. The update cycle of the charge and discharge current sharing coefficient can be controlled within 100ms. It has a high response speed and low cost, and can be applied to scenarios with high response speed requirements and low cost.

[0073] This invention also provides a battery management system for implementing the above embodiments and preferred embodiments, which will not be repeated hereafter. As used below, the term "module" can refer to a combination of software and / or hardware that implements a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0074] Figure 5 is a structural block diagram of a battery management system provided in an embodiment of the present invention. The present invention provides a battery management system applied to the above-mentioned parallel battery system. The parallel battery system includes a battery management system and multiple parallel battery clusters. As shown in Figure 5, the battery management system 500 includes: an acquisition unit 501, used to acquire battery operating status information of each battery cluster. The battery operating status information includes the working current limit value and rated capacity of the battery cluster.

[0075] The current sharing coefficient calculation unit 502 is used to obtain the working current sharing coefficient of each battery cluster based on the working current limit value and rated capacity of each battery cluster.

[0076] The current sharing control unit 503 is used to control the operating current of each battery cluster according to the operating current sharing coefficient of each battery cluster.

[0077] In this embodiment of the invention, the battery management system 500 is the host battery management system in the parallel battery system.

[0078] The battery management system 500 provided in this embodiment of the invention can execute the battery current sharing control method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects for executing the method. Further functional descriptions of the various modules and units described above are the same as in the corresponding embodiments described above, and will not be repeated here.

[0079] Figure 6 is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention.

[0080] Referring specifically to FIG6, a schematic diagram of a suitable electronic device for implementing embodiments of the present invention is shown below. The electronic device may include a processor (e.g., a central processing unit, a graphics processing unit, etc.) 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from memory 608 into random access memory (RAM) 603. The RAM 603 also stores various programs and data required for the operation of the electronic device. The processor 601, ROM 602, and RAM 603 are interconnected via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0081] Typically, the following devices can be connected to I / O interface 605: input devices 606 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 607 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 608 including, for example, magnetic tapes, hard disks, etc.; and communication devices 609. Communication device 609 allows the electronic device to communicate wirelessly or wiredly with other devices to exchange data. Although FIG6 shows an electronic device with various devices, it should be understood that it is not required to implement or have all the devices shown, and more or fewer devices may be implemented or have instead.

[0082] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 609, or installed from a memory 608, or installed from a ROM 602. When the computer program is executed by the processor 601, it performs the functions defined in the battery current sharing control method of the embodiments of the present invention.

[0083] The electronic device shown in Figure 6 is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the present invention.

[0084] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the battery current sharing control method shown in the above embodiments is implemented.

[0085] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0086] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery current sharing control method, characterized in that, An application to a parallel-connected battery system, the parallel-connected battery system comprising multiple parallel battery clusters, the method comprising: acquiring battery operating status information of each battery cluster, the battery operating status information including the operating current limit value and rated capacity of each battery cluster; acquiring the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster; and performing current sharing control on the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster.

2. The method according to claim 1, characterized in that, The battery cluster system further includes multiple battery management systems, each connected to a battery cluster in a one-to-one correspondence. The step of obtaining the battery operating status information of each battery cluster includes receiving the battery operating status information of each battery cluster fed back by each battery management system.

3. The method according to claim 1, characterized in that, The step of obtaining the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster includes: determining the capacity ratio of each battery cluster based on the rated capacity of each battery cluster; determining the current limit value ratio of each battery cluster based on the operating current limit value of each battery cluster; and determining the operating current sharing coefficient of each battery cluster based on the product of the rated capacity ratio and the current limit value ratio of each battery cluster.

4. The method according to claim 3, characterized in that, The capacity ratio of the battery cluster is the ratio of the rated capacity of the battery cluster to the sum of the rated capacities of all the battery clusters.

5. The method according to claim 3, characterized in that, The current limiting value of the battery cluster is the ratio of the operating current limiting value of the battery cluster to the sum of the operating current limiting values ​​of all battery clusters.

6. The method according to claim 1, characterized in that, The step of controlling the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster includes: for each battery cluster, determining a first candidate current of the battery cluster based on the product of the operating current sharing coefficient of the battery cluster and the maximum operating current, wherein the maximum operating current is the current output from the external power supply to the battery cluster or the current output from the battery cluster to the load; determining a target current corresponding to the battery cluster from the first candidate current and the second candidate current, wherein the second candidate current is the current operating current limit value of the battery cluster; and controlling the operating current of the battery cluster to the corresponding target current.

7. The method according to claim 6, characterized in that, The battery cluster system also includes multiple current controllers, each connected to a battery cluster in a corresponding manner. Controlling the operating current of the battery cluster to the target current includes controlling the operating current of the corresponding battery cluster to the corresponding target current through the current controller.

8. The method according to claim 6, characterized in that, Determining the target current corresponding to the battery cluster from the first candidate current and the second candidate current includes: determining the minimum value between the first candidate current and the second candidate current as the target current corresponding to the battery cluster.

9. A battery management system, characterized in that, This invention relates to a parallel-connected battery system, which includes a battery management system and multiple parallel-connected battery clusters. The battery management system includes: an acquisition unit for acquiring battery operating status information of each battery cluster, including the operating current limit value and rated capacity of each battery cluster; a current sharing coefficient calculation unit for acquiring the operating current sharing coefficient of each battery cluster based on the operating current limit value and rated capacity of each battery cluster; and a current sharing control unit for controlling the operating current of each battery cluster based on the operating current sharing coefficient of each battery cluster.

10. An electronic device, characterized in that, include: A memory and a processor are communicatively connected, the memory stores computer instructions, and the processor executes the computer instructions to perform the battery current sharing control method according to any one of claims 1 to 8.

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