Multi-battery pack parallel control method and system

Abstract

This application discloses a method and system for parallel control of multiple battery packs, relating to the field of battery control technology. The method includes: acquiring a first voltage value of a first battery pack and a second voltage value of a second battery pack; determining a master node battery pack and a slave node battery pack based on the magnitudes of the first and second voltage values; calculating the parallel current of the slave node battery pack using the master node battery pack; acquiring the continuous withstand current of the slave node battery pack; when the parallel current is less than the continuous withstand current, connecting the master node battery pack and the slave node battery pack in parallel via a switching module, so that the master node battery pack and the slave node battery pack are connected to a vehicle module or a charging module; when the parallel current is greater than the continuous withstand current, connecting a current regulation module to the master node battery pack and the slave node battery pack via the switching module, so as to reduce the parallel current to less than the continuous withstand current. This application can improve the safety during the parallel connection process of battery packs.

Description

Technical Field

[0001] This application relates to the field of battery control technology, and in particular to a method and system for parallel control of multiple battery packs. Background Technology

[0002] In related technologies, such as electric vehicles and energy storage power stations, multiple battery packs are typically required to meet the demands for high energy density and long lifespan. To improve vehicle range, parallel connection of multiple battery packs is gaining increasing importance in vehicle technology, as it can enhance both vehicle power and range.

[0003] It's worth noting that parallel battery packs can combine battery packs of different capacities, models, and specifications, effectively improving energy density and power density, thereby enhancing vehicle performance. However, current methods for parallel multi-battery pack connection often lack precise control, easily leading to excessive current during the parallel process and posing a risk of battery pack damage. Therefore, improving the safety of parallel battery pack connection has become a pressing technical issue. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a method and system for controlling the parallel connection of multiple battery packs, which can improve the safety during the parallel connection process of battery packs.

[0005] The multi-battery pack parallel control method according to the first aspect of this application is applied to a multi-battery pack parallel control system, the multi-battery pack parallel control system including: a first battery pack, a second battery pack, a vehicle module, a charging module, a switching module, and a current regulation module, wherein the first battery pack and the second battery pack communicate via a bus;

[0006] The method for parallel control of multiple battery packs includes:

[0007] Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack;

[0008] The master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value.

[0009] The parallel current of the slave node battery pack is calculated using the master node battery pack, wherein the parallel current is the loop current when the slave node battery pack and the master node battery pack are connected in parallel;

[0010] Obtain the continuous withstand current of the slave node battery pack;

[0011] When the parallel current is less than the continuous withstand current, the master node battery pack and the slave node battery pack are connected in parallel through the switching module so that the master node battery pack and the slave node battery pack are connected to the vehicle module or the charging module.

[0012] When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current.

[0013] The multi-battery pack parallel control method according to the embodiments of this application has at least the following beneficial effects: First, obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack; second, determine the master node battery pack and the slave node battery pack based on the magnitudes of the first and second voltage values; third, calculate the parallel current of the slave node battery pack using the master node battery pack; fourth, obtain the continuous withstand current of the slave node battery pack; fifth, when the parallel current is less than the continuous withstand current, connect the master node battery pack and the slave node battery pack in parallel using a switching module, so that the master node battery pack and the slave node battery pack are connected to the vehicle module or charging module; sixth, when the parallel current is greater than the continuous withstand current, connect the current regulation module to the master node battery pack and the slave node battery pack using a switching module, so as to reduce the parallel current to less than the continuous withstand current. The multi-battery pack parallel control method of this application, by calculating the parallel current, performs parallel connection when the parallel current is less than the continuous withstand current, and reduces the parallel current before parallel connection when the parallel current is greater than the continuous withstand current, effectively reducing the risk of excessive current during parallel connection and improving the safety of battery pack parallel connection. Therefore, the multi-battery pack parallel control method of this application can improve the safety during the parallel connection process of battery packs.

[0014] According to some embodiments of the first aspect of this application, obtaining the first voltage value of the first battery pack and the second voltage value of the second battery pack includes:

[0015] The system is initialized by a wake-up signal, and the first voltage value of the first battery pack and the second voltage value of the second battery pack are obtained through bus communication.

[0016] According to some embodiments of the first aspect of this application, determining the master node battery pack and the slave node battery pack based on the magnitudes of the first voltage value and the second voltage value includes:

[0017] When the wake-up signal is a discharge status indication signal, the battery pack with the highest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as the slave node battery packs.

[0018] When the wake-up signal is a charging status indication signal, the battery pack with the lowest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as the slave node battery packs.

[0019] According to some embodiments of the first aspect of this application, the step of calculating the parallel current of the slave node battery pack through the master node battery pack includes:

[0020] Obtain the third voltage value corresponding to the master node battery pack and the fourth voltage value corresponding to the slave node battery pack;

[0021] Calculate the difference between the third voltage value and the fourth voltage value, and determine the difference as the battery pack voltage difference;

[0022] Calculate the first internal resistance of the master node battery pack and the second internal resistance of the slave node battery pack, and sum the first internal resistance and the second internal resistance to obtain the sum of the battery pack internal resistances;

[0023] The parallel current of the slave node battery pack is obtained by quotienting the voltage difference of the battery pack, the internal resistance of the battery pack, and the voltage difference of the battery pack.

[0024] According to some embodiments of the first aspect of this application, the switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch;

[0025] The step of connecting the master node battery pack and the slave node battery pack in parallel via the switching module when the parallel current is less than the continuous withstand current includes:

[0026] When the parallel current is less than the continuous withstand current, the master node battery pack is paralleled through the first positive circuit switch and the first negative circuit switch, and the slave node battery pack is paralleled through the second positive circuit switch and the second negative circuit switch.

[0027] According to some embodiments of the first aspect of this application, the switching module further includes a first pre-charge circuit switch and a second pre-charge circuit switch, and the current regulation module includes a first pre-charge resistor and a second pre-charge resistor;

[0028] When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack via the switching module, including:

[0029] When the parallel current is greater than the continuous withstand current, the first precharge resistor is connected to the master node battery pack through the first precharge circuit switch, and the second precharge resistor is connected to the slave node battery pack through the second precharge circuit switch.

[0030] The multi-battery pack parallel control system according to the second aspect of this application includes:

[0031] Vehicle module;

[0032] Charging module;

[0033] Switch module;

[0034] The first battery pack is electrically connected to the vehicle module when discharging; and is electrically connected to the charging module when charging.

[0035] The second battery pack is electrically connected to the vehicle module when discharging; it is electrically connected to the charging module when charging; the second battery pack and the first battery pack communicate via a bus.

[0036] Current regulation module;

[0037] The control module is used to perform the following steps:

[0038] Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack;

[0039] The master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value.

[0040] The parallel current of the slave node battery pack is calculated using the master node battery pack.

[0041] Obtain the continuous withstand current of the slave node battery pack;

[0042] When the parallel current is less than the continuous withstand current, the master node battery pack and the slave node battery pack are connected in parallel through the switching module so that the master node battery pack and the slave node battery pack are connected to the vehicle module or the charging module.

[0043] When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current.

[0044] According to some embodiments of the second aspect of this application, the switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch;

[0045] When the parallel current is less than the continuous withstand current, the first positive circuit switch and the first negative circuit switch are used to parallel the master node battery pack, and the second positive circuit switch and the second negative circuit switch are used to parallel the slave node battery pack.

[0046] According to some embodiments of the second aspect of this application, the switching module further includes a first pre-charge circuit switch and a second pre-charge circuit switch, and the current regulation module includes a first pre-charge resistor and a second pre-charge resistor;

[0047] When the parallel current is greater than the continuous withstand current, the first precharge circuit switch is used to connect the first precharge resistor to the master node battery pack, and the second precharge circuit switch is used to connect the second precharge resistor to the slave node battery pack.

[0048] According to some embodiments of the second aspect of this application, the multi-battery pack parallel control system further includes a current detection module, which is used to detect the first circuit current of the first battery pack and the second circuit current of the second battery pack during charging or discharging, so as to obtain the current change during the parallel connection process of the battery packs.

[0049] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0050] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0051] Figure 1 This is a connection diagram of a multi-battery pack parallel control system provided in one embodiment of this application;

[0052] Figure 2 This is a schematic diagram of the connection of a multi-battery pack according to an embodiment of this application;

[0053] Figure 3 This is a flowchart illustrating a method for controlling multiple battery packs in parallel according to an embodiment of this application.

[0054] Figure 4 This is a flowchart illustrating a multi-battery pack parallel control method provided in another embodiment of this application;

[0055] Figure 5 This is a schematic diagram of the structure of a multi-battery pack parallel control system provided in another embodiment of this application.

[0056] Figure label:

[0057] Memory 200, processor 300. Detailed Implementation

[0058] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0059] It should be noted that although functional modules are divided in the system 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 system or the order in the flowchart. The terminology in the specification, claims, and the foregoing figures is used to distinguish similar objects and is not necessarily used to describe a specific order or sequence.

[0060] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0061] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0062] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] Below, according to Figure 1-4 This application describes a method for controlling the parallel connection of multiple battery packs according to embodiments of the present application.

[0064] It is understandable that, such as Figure 1 , Figure 2 and Figure 3As shown, a method for parallel control of multiple battery packs is provided, which is applied to a parallel control system of multiple battery packs. The parallel control system of multiple battery packs includes: a first battery pack, a second battery pack, a vehicle module, a charging module, a switching module, and a current regulation module. The first battery pack and the second battery pack communicate with each other through a bus.

[0065] Parallel control methods for multiple battery packs include:

[0066] Step S100: Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack;

[0067] Step S110: Determine the master node battery pack and slave node battery pack based on the magnitude of the first voltage value and the second voltage value;

[0068] Step S120: Calculate the parallel current of the slave node battery pack through the master node battery pack, where the parallel current is the loop current when the slave node battery pack and the master node battery pack are connected in parallel.

[0069] Step S130: Obtain the continuous withstand current of the battery pack at the slave node;

[0070] Step S140: When the parallel current is less than the continuous withstand current, the main node battery pack and the slave node battery pack are connected in parallel through the switching module so that the main node battery pack and the slave node battery pack are connected to the vehicle module or the charging module.

[0071] In step S150, when the parallel current is greater than the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current.

[0072] The first step involves obtaining the first voltage value of the first battery pack and the second voltage value of the second battery pack. The second step involves determining the master and slave battery packs based on the first and second voltage values. The third step involves calculating the parallel current of the slave battery packs using the master battery pack. The fourth step involves obtaining the continuous withstand current of the slave battery pack. The fifth step involves connecting the master and slave battery packs in parallel using a switching module when the parallel current is less than the continuous withstand current, so that they can be connected to the vehicle module or charging module. The sixth step involves connecting the current regulation module to the master and slave battery packs using a switching module when the parallel current is greater than the continuous withstand current, so as to reduce the parallel current to less than the continuous withstand current. This multi-battery pack parallel control method, by calculating the parallel current, performs paralleling when the parallel current is less than the continuous withstand current and reduces the parallel current before paralleling when the parallel current is greater than the continuous withstand current, effectively reducing the risk of excessive current during paralleling and improving the safety of parallel battery pack connection. Therefore, the multi-battery pack parallel control method of this application can improve the safety during the parallel connection process of battery packs.

[0073] In the electric vehicle sector, parallel battery packs can improve vehicle power and range. Parallel battery packs allow for the combination of battery packs of different capacities, models, and specifications to achieve optimal energy and power density, thereby enhancing vehicle performance. Furthermore, some high-performance electric vehicles and hybrid vehicles also utilize series-parallel battery pack configurations to further improve vehicle power and range.

[0074] In the field of energy storage systems, parallel connection of battery packs enables flexible capacity configuration and voltage output to meet the power and energy needs of different users. Furthermore, different individual cells within a battery pack can also be connected in parallel to achieve higher current output capabilities.

[0075] It should be noted that, as Figure 1 As shown, each battery pack is equipped with a control board, which contains a communication chip. The battery packs communicate with each other via a bus.

[0076] It should be noted that, as Figure 1 and Figure 2 As shown, each battery pack needs to be charged and discharged. The charging port of the battery pack is connected to the charging module, and the discharging port of the battery pack is connected to the vehicle module. The charging and discharging ports can be the same.

[0077] It is understandable that obtaining the first voltage value of the first battery pack and the second voltage value of the second battery pack includes:

[0078] The system is initialized by a wake-up signal, and the first voltage value of the first battery pack and the second voltage value of the second battery pack are obtained through bus communication.

[0079] It should be noted that the battery packs in the multi-battery pack parallel control system communicate with each other via a bus. After the multi-battery pack parallel control system is activated, during the entire system initialization process, each battery pack will send the current battery pack voltage information, that is, the voltage value, to each other.

[0080] It is understandable that the master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value, including:

[0081] When the wake-up signal is a discharge status indication signal, the battery pack with the highest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as slave node battery packs.

[0082] When the wake-up signal is a charging status indication signal, the battery pack with the lowest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as slave node battery packs.

[0083] It is understandable that the calculation of the parallel current of the slave node battery pack through the master node battery pack includes:

[0084] Get the third voltage value corresponding to the battery pack of the master node and the fourth voltage value corresponding to the battery pack of the slave node.

[0085] Calculate the difference between the third and fourth voltage values, and determine the difference as the battery pack voltage difference;

[0086] Calculate the first internal resistance of the master node battery pack and the second internal resistance of the slave node battery pack, and sum the first internal resistance and the second internal resistance to obtain the sum of the battery pack internal resistances.

[0087] The parallel current of the battery pack at the slave node is obtained by quotienting the voltage difference of the battery pack, the internal resistance of the battery pack, and the voltage difference of the battery pack.

[0088] It should be noted that the battery pack voltage difference refers to the fact that each battery pack has its own module voltage, and the module voltages between battery packs are different, so there is a voltage difference between battery packs.

[0089] The internal resistance of a battery refers to the voltage difference between battery packs. When battery packs are connected in parallel, the voltage difference causes the battery packs to charge and discharge each other. Therefore, the circuit impedance is the series impedance of the battery packs, which is the internal resistance of the battery packs.

[0090] It is understood that the switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch;

[0091] When the parallel current is less than the continuous withstand current, the master node battery pack and the slave node battery pack are connected in parallel via the switching module, including:

[0092] When the parallel current is less than the continuous withstand current, the master node battery pack is paralleled through the first positive circuit switch and the first negative circuit switch, and the slave node battery pack is paralleled through the second positive circuit switch and the second negative circuit switch.

[0093] It should be noted that circuit switches include, but are not limited to, MOSFETs, and may also include electronic switches (such as MOSFETs / silicon carbide / IGBTs, etc.), mechanical switches (such as contactors / relays, etc.), and all other switching devices that can be used to control circuits.

[0094] It is understandable that the switching module also includes a first pre-charge circuit switch and a second pre-charge circuit switch, and the current regulation module includes a first pre-charge resistor and a second pre-charge resistor;

[0095] When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack via the switching module, including:

[0096] When the parallel current exceeds the continuous withstand current, the first pre-charge resistor is connected to the master node battery pack through the first pre-charge circuit switch, and the second pre-charge resistor is connected to the slave node battery pack through the second pre-charge circuit switch.

[0097] It should be noted that the first pre-charge resistor and the second pre-charge resistor are closed simultaneously to limit the current. Because the pre-charge resistor has a power limit, when the detected circuit current is small, the current can be limited by one pre-charge resistor. During discharge, the pre-charge circuit of the battery pack with the higher voltage is disconnected first, and during charging, the pre-charge circuit of the battery pack with the lower voltage is disconnected first. The battery pack pre-charge circuit includes the first pre-charge circuit switch and the first pre-charge resistor, or the second pre-charge circuit switch and the second pre-charge resistor.

[0098] It should be noted that, as Figure 2 The diagram shows the internal structure of the battery pack. Battery pack 1 is the first battery pack, and battery pack 2 is the second battery pack. Battery pack 1 and battery pack 2 are connected to the vehicle module or charging module via a positive circuit switch, a pre-charge circuit switch, and a negative circuit switch. The pre-charge resistor (which can be either the first or second pre-charge resistor) and the pre-charge circuit switch are used to balance the battery packs to be paralleled when the current battery pack is not suitable for paralleling. During paralleling, if the circuit current exceeds the battery pack's capacity, the pre-charge resistor ensures that the current during paralleling is less than the battery pack's tolerance. The pre-charge resistor can be located at either end of the positive circuit switch or the negative circuit switch. The current detection module detects the battery pack's circuit charging and discharging current and participates in the paralleling and charging / discharging process strategy.

[0099] It should be noted that the loop current is equal to the voltage divided by the resistance. The voltage is the voltage difference of the battery pack, and the resistance is the sum of the internal resistances of the battery pack. However, the sum of the internal resistances is generally very small, which will result in a very large loop current. If a pre-charging resistor is connected in series, it will increase the loop impedance and reduce the loop current.

[0100] It should be noted that, as Figure 4 As shown, after determining the master and slave nodes based on charging and discharging, the parallel current I needs to be calculated, where I = battery pack voltage difference / sum of battery pack internal resistances. Then, the continuous withstand current I0 is obtained from a table, and the control strategy is determined by comparing the magnitudes of I and I0.

[0101] Specifically, the paralleling of battery packs is determined by the current SOP (State of Operation) of the battery pack. Based on the current state and voltage of the battery pack, the maximum SOP that the current battery pack can withstand is obtained from a table. The maximum current that the current battery pack can withstand is calculated. Whether to open the battery pack pre-charge circuit is determined based on whether the maximum current caused by the voltage difference of the battery packs during paralleling is lower than the maximum current that the current battery pack can withstand. If the circuit current is less than the maximum current that the current battery pack can withstand during paralleling, the positive and negative circuit switches can be closed directly to complete the paralleling process. Otherwise, the battery pack pre-charge circuit needs to be closed to limit the circuit current during paralleling until the battery pack voltage is suitable for completing the paralleling operation, and then the paralleling process is completed.

[0102] The following guidelines must be followed during the parallel connection process of battery packs in a multi-battery pack parallel control system:

[0103] Discharge status: The paralleling sequence is completed one by one from high to low battery pack voltage until all battery packs are paralleled.

[0104] Charging status: The paralleling sequence is completed one by one from low to high battery voltage until all battery packs are paralleled.

[0105] It is understood that this application also provides a multi-battery pack parallel control system, including:

[0106] Vehicle module;

[0107] Charging module;

[0108] Switch module;

[0109] When discharging, the first battery pack is electrically connected to the vehicle module; when charging, the first battery pack is electrically connected to the charging module.

[0110] The second battery pack is electrically connected to the vehicle module when discharging; it is electrically connected to the charging module when charging; and it communicates with the first battery pack via a bus.

[0111] Current regulation module;

[0112] The control module is used to perform the following steps:

[0113] Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack;

[0114] The master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value.

[0115] The parallel current of the slave node battery pack is calculated by the master node battery pack, where the parallel current is the loop current when the slave node battery pack and the master node battery pack are connected in parallel.

[0116] Obtain the continuous withstand current of the battery pack at the node;

[0117] When the parallel current is less than the continuous withstand current, the main node battery pack and the slave node battery pack are connected in parallel through the switching module so that the main node battery pack and the slave node battery pack can be connected to the vehicle module or the charging module.

[0118] When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current.

[0119] It is understood that the switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch;

[0120] When the parallel current is less than the continuous withstand current, the first positive circuit switch and the first negative circuit switch are used to parallel the master node battery pack, and the second positive circuit switch and the second negative circuit switch are used to parallel the slave node battery pack.

[0121] It is understandable that the switching module also includes a first pre-charge circuit switch and a second pre-charge circuit switch, and the current regulation module includes a first pre-charge resistor and a second pre-charge resistor;

[0122] When the parallel current is greater than the continuous withstand current, the first precharge circuit switch is used to connect the first precharge resistor to the master node battery pack, and the second precharge circuit switch is used to connect the second precharge resistor to the slave node battery pack.

[0123] Understandably, the multi-battery pack parallel control system also includes a current detection module. The current detection module is used to detect the first circuit current of the first battery pack and the second circuit current of the second battery pack during charging or discharging, so as to obtain the current change during the parallel connection process of the battery packs.

[0124] The following reference Figure 5 This application describes a multi-battery pack parallel control system according to embodiments thereof.

[0125] It is understandable that, such as Figure 5 As shown, the multi-battery pack parallel control system includes:

[0126] At least one memory 200;

[0127] At least one processor 300;

[0128] At least one program;

[0129] The program is stored in memory 200, and processor 300 executes at least one program to implement the above-described multi-battery pack parallel control method. Figure 5 Take a processor 300 as an example.

[0130] The processor 300 and the memory 200 can be connected via a bus or other means. Figure 5 Take a bus connection as an example.

[0131] The memory 200, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and signals, such as the program instructions / signals corresponding to the multi-battery pack parallel control system in the embodiments of this application. The processor 300 executes various functional applications and data processing by running the non-transitory software programs, instructions, and signals stored in the memory 200, thereby implementing the multi-battery pack parallel control method of the above-described method embodiments.

[0132] The memory 200 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store relevant data for the aforementioned multi-battery pack parallel control method. Furthermore, the memory 200 may include high-speed random access memory and non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 200 may optionally include memory remotely located relative to the processor 300, and these remote memories can be connected to the multi-battery pack parallel control system via a network. Examples of such networks include, but are not limited to, the Internet of Things (IoT), software-defined networks, sensor networks, the Internet, enterprise intranets, local area networks (LANs), mobile communication networks, and combinations thereof.

[0133] One or more signals are stored in memory 200, and when executed by one or more processors 300, the multi-battery pack parallel control method described in any of the above method embodiments is executed. For example, the above-described method is executed. Figure 3 or Figure 4 The method in the middle.

[0134] The following reference Figure 5 This application describes a computer-readable storage medium according to embodiments thereof.

[0135] like Figure 5 As shown, a computer-readable storage medium stores computer-executable instructions that are executed by one or more processors 300, for example, by... Figure 5 One or more processors 300 may execute the multi-battery pack parallel control method described in the above method embodiments, thereby enabling the processors 300 to perform the method described above. For example, executing the method described above... Figure 3 or Figure 4 The method in the middle.

[0136] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0137] Based on the above description of the embodiments, those skilled in the art will understand that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media and communication media. As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital multifunction disk or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable signals, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and can include any information delivery medium.

[0138] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A method for parallel control of multiple battery packs, characterized in that, This invention relates to a multi-battery pack parallel control system, which includes: a first battery pack, a second battery pack, a vehicle module, a charging module, a switching module, and a current regulation module. The first battery pack and the second battery pack communicate via a bus. The method for parallel control of multiple battery packs includes: Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack; The master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value. The parallel current of the slave node battery pack is calculated using the master node battery pack, wherein the parallel current is the loop current when the slave node battery pack and the master node battery pack are connected in parallel; Obtain the continuous withstand current of the slave node battery pack; When the parallel current is less than the continuous withstand current, the master node battery pack and the slave node battery pack are connected in parallel through the switching module so that the master node battery pack and the slave node battery pack are connected to the vehicle module or the charging module. When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current. The step of calculating the parallel current of the slave node battery pack through the master node battery pack includes: Obtain the third voltage value corresponding to the master node battery pack and the fourth voltage value corresponding to the slave node battery pack; Calculate the difference between the third voltage value and the fourth voltage value, and determine the difference as the battery pack voltage difference; Calculate the first internal resistance of the master node battery pack and the second internal resistance of the slave node battery pack, and sum the first internal resistance and the second internal resistance to obtain the sum of the battery pack internal resistances; The parallel current of the slave node battery pack is obtained by quoting the voltage difference of the battery pack, the internal resistance of the battery pack, and the sum of the two. The switching module includes a first pre-charge circuit switch and a second pre-charge circuit switch, and the current regulation module includes a first pre-charge resistor and a second pre-charge resistor. When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack via the switching module, including: When the parallel current is greater than the continuous withstand current, the first precharge resistor is connected to the master node battery pack through the first precharge circuit switch, and the second precharge resistor is connected to the slave node battery pack through the second precharge circuit switch.

2. The multi-battery pack parallel control method according to claim 1, characterized in that, The step of obtaining the first voltage value of the first battery pack and the second voltage value of the second battery pack includes: The system is initialized by a wake-up signal, and the first voltage value of the first battery pack and the second voltage value of the second battery pack are obtained through bus communication.

3. The multi-battery pack parallel control method according to claim 2, characterized in that, The step of determining the master node battery pack and slave node battery pack based on the magnitudes of the first voltage value and the second voltage value includes: When the wake-up signal is a discharge status indication signal, the battery pack with the highest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as the slave node battery packs. When the wake-up signal is a charging status indication signal, the battery pack with the lowest voltage among the first voltage value and the second voltage value is designated as the master node battery pack, and the rest are designated as the slave node battery packs.

4. The multi-battery pack parallel control method according to claim 1, characterized in that, The switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch; The step of connecting the master node battery pack and the slave node battery pack in parallel via the switching module when the parallel current is less than the continuous withstand current includes: When the parallel current is less than the continuous withstand current, the master node battery pack is paralleled through the first positive circuit switch and the first negative circuit switch, and the slave node battery pack is paralleled through the second positive circuit switch and the second negative circuit switch.

5. A multi-battery pack parallel control system, characterized in that, include: Vehicle module; Charging module; Switch module; The first battery pack is electrically connected to the vehicle module when discharging. When charging, the first battery pack and the charging module are electrically connected; The second battery pack is electrically connected to the vehicle module when discharging; it is electrically connected to the charging module when charging; the second battery pack and the first battery pack communicate via a bus. Current regulation module; The control module is used to perform the following steps: Obtain the first voltage value of the first battery pack and the second voltage value of the second battery pack; The master node battery pack and slave node battery pack are determined based on the magnitude of the first voltage value and the second voltage value. Obtain the third voltage value corresponding to the master node battery pack and the fourth voltage value corresponding to the slave node battery pack; Calculate the difference between the third voltage value and the fourth voltage value, and determine the difference as the battery pack voltage difference; Calculate the first internal resistance of the master node battery pack and the second internal resistance of the slave node battery pack, and sum the first internal resistance and the second internal resistance to obtain the sum of the battery pack internal resistances; The parallel current of the slave node battery pack is obtained by quotienting the voltage difference of the battery pack, the internal resistance of the battery pack, and the parallel current is the loop current when the slave node battery pack and the master node battery pack are connected in parallel. Obtain the continuous withstand current of the slave node battery pack; When the parallel current is less than the continuous withstand current, the master node battery pack and the slave node battery pack are connected in parallel through the switching module so that the master node battery pack and the slave node battery pack are connected to the vehicle module or the charging module. When the parallel current exceeds the continuous withstand current, the current regulation module is connected to the master node battery pack and the slave node battery pack through the switching module to reduce the parallel current to less than the continuous withstand current. The switching module includes a first precharge circuit switch and a second precharge circuit switch, and the current regulation module includes a first precharge resistor and a second precharge resistor. When the parallel current is greater than the continuous withstand current, the first precharge circuit switch is used to connect the first precharge resistor to the master node battery pack, and the second precharge circuit switch is used to connect the second precharge resistor to the slave node battery pack.

6. The multi-battery pack parallel control system according to claim 5, characterized in that, The switching module includes a first positive circuit switch, a second positive circuit switch, a first negative circuit switch, and a second negative circuit switch; When the parallel current is less than the continuous withstand current, the first positive circuit switch and the first negative circuit switch are used to parallel the master node battery pack, and the second positive circuit switch and the second negative circuit switch are used to parallel the slave node battery pack.

7. The multi-battery pack parallel control system according to claim 5, characterized in that, The multi-battery pack parallel control system also includes a current detection module, which is used to detect the first circuit current of the first battery pack and the second circuit current of the second battery pack during charging or discharging, so as to obtain the current change during the parallel connection process of the battery packs.

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