Multi-battery-pack parallel control circuit and electronic equipment

Abstract

The utility model relates to the field of battery application, in particular to a multi-battery-pack parallel control circuit and electronic equipment. The circuit comprises a plurality of battery packs, a first confluence line, a second confluence line, a direct-current converter and a controller, the input end of the direct-current converter is connected with the first confluence line; the output end of the direct-current converter is connected with the second confluence line; the plurality of battery packs are connected in parallel with the first confluence line and supply power to external equipment through the first confluence line; the plurality of battery packs are connected in parallel with the second confluence line and are connected with the direct-current converter through the second confluence line; and the controller is respectively in communication connection with the plurality of battery packs. According to the circuit, the second confluence line of the battery pack to be charged is conducted, and the discharging battery pack is conducted with the first confluence line, so that the discharging battery pack charges the battery pack to be charged, the electric quantity difference between the battery packs is kept relatively balanced, and the circulating current problem caused by direct parallel connection of the battery packs is effectively avoided.

Description

Technical Field

[0001] This application relates to the field of battery applications, and further relates to a multi-battery pack parallel control circuit and an electronic device. Background Art

[0002] In the actual application process of new energy battery packs such as battery packs containing battery cells, it often occurs that a single battery pack cannot meet the requirements. In this case, generally, multiple battery packs are connected in series or in parallel. Connecting multiple battery packs in series will increase the voltage on the output side of multiple battery packs, which will cause the subsequent electrical equipment to be unable to be directly used due to excessive voltage. However, the method of connecting multiple battery packs in parallel has obvious application advantages compared with series connection because the output side voltage will not increase significantly. However, since the consistency of each battery pack is not the same, if directly connected in parallel, there may be a large circulating current between multiple battery packs, which will damage the battery and even cause a fire. Summary of the Utility Model

[0003] To solve the above technical problems, this application provides a multi-battery pack parallel control circuit and an electronic device, which avoid the circulating current problem caused by directly connecting multiple battery packs in parallel.

[0004] In a first aspect, this application provides a multi-battery pack parallel control circuit, including: multiple battery packs, a first bus line, a second bus line, a DC converter, and a controller; the input end of the DC converter is connected to the first bus line, and the output end of the DC converter is connected to the second bus line; multiple battery packs are connected to the first bus line in parallel to supply power to external devices through the first bus line; multiple battery packs are connected to the second bus line in parallel and are connected to the DC converter through the second bus line; the controller is communicatively connected to multiple battery packs respectively.

[0005] In the above multi-battery pack parallel control circuit, by conducting the second bus line of the battery pack to be charged and conducting the discharging battery pack to the first bus line, the discharging battery pack charges the battery pack to be charged, thereby keeping the power difference between each battery pack relatively balanced, effectively avoiding the circulating current problem caused by directly connecting each battery pack in parallel. At the same time, when each battery pack supplies power to external devices in parallel, if one of the battery packs is damaged, it does not affect the other battery packs to supply power to external devices, improving the compatibility and user experience of this circuit.

[0006] In one implementation, multiple of the battery packs each include a battery management system, which is configured to obtain the voltage and SOC of its respective battery pack, and send the voltage and the SOC to the controller respectively; the controller calculates the voltage difference and the SOC difference between multiple battery packs based on the voltages and SOCs of the multiple battery packs; the controller determines that the battery pack with the voltage difference or the SOC difference exceeding the safety threshold enters the charging state according to whether both the voltage difference and the SOC difference are within the safety threshold; the controller controls the battery pack entering the charging state to be connected to the second bus line, and starts the DC converter to charge the battery pack entering the charging state from the first bus line through the DC converter.

[0007] In one implementation, it further includes: multiple first switches and multiple second switches; the multiple first switches correspond to the multiple battery packs one by one, and one end of each first switch is connected to the corresponding battery pack, and the other end is connected to the first bus line; the multiple second switches correspond to the multiple battery packs one by one, and one end of each second switch is connected to the corresponding battery pack, and the other end is connected to the second bus line.

[0008] In one implementation, it further includes: the controller controls the battery pack entering the charging state to disconnect its corresponding first switch and close its corresponding second switch, so that the DC converter converts electrical energy from the first bus line to charge the battery pack entering the charging state until the voltage difference and the SOC difference between the battery pack entering the charging state and other battery packs are both within the safety threshold, then disconnects its corresponding second switch and closes its corresponding first switch.

[0009] For the above multi-battery-pack parallel control circuit, the controller obtains the voltage or SOC of each battery pack through the battery management system of each battery pack, and calculates the voltage difference or SOC difference between each battery pack. If there is a battery pack with a voltage difference or an SOC difference exceeding the safety threshold among the multiple battery packs, the controller determines that the battery pack exceeding the safety threshold enters the charging state. At this time, the controller issues a charging instruction to the battery management system of the battery pack entering the charging state, thereby controlling the second switch corresponding to the battery pack entering the charging state to close and the first switch to remain open; the controller issues a discharging instruction to the battery management system of the battery pack not entering the charging state, thereby controlling the first switch corresponding to the battery pack not entering the charging state to close and the second switch to remain open, so as to charge the battery pack entering the charging state until the voltage difference and the SOC difference between the battery pack entering the charging state and the battery pack not entering the charging state are both within the safety threshold, then close the first switch corresponding to the battery pack entering the charging state and disconnect the corresponding second switch. In this way, the circulating current problem caused by directly paralleling multiple battery packs can be avoided.

[0010] In one implementation, it further includes: if there are multiple battery packs among the multiple battery packs whose voltage differences or SOC differences are greater than the safety threshold, the controller sorts them according to the magnitude of the differences in the voltage differences or SOC differences, and preferentially arranges the battery pack with the largest difference to enter the charging state.

[0011] In one implementation, it further includes: the controller re-detects the voltage differences and SOC differences of the multiple battery packs at regular time intervals, and re-adjusts the order in which the battery packs enter the charging state according to the magnitude of the differences, until the voltage differences and SOC differences of the multiple battery packs are all within the safety threshold.

[0012] The above multi-battery-pack parallel control circuit, for the case where the voltage differences or SOC differences of multiple battery packs are all greater than the safety threshold, preferentially charges the battery pack with the largest voltage difference or SOC difference that enters the charging state. After a certain time interval, it re-detects and sorts the voltage differences or SOC differences between each battery pack, and repeatedly charges the battery pack with the largest voltage difference or SOC difference after each sorting that enters the charging state, further improving the compatibility of this method and avoiding the circulating current problem caused by directly paralleling multiple battery packs.

[0013] In one implementation, it further includes: a third switch, one end of the third switch is connected to the first bus line, and the other end is connected to the external device.

[0014] In one implementation, it further includes: when there are no battery packs among the multiple battery packs whose voltage differences and SOC differences are greater than the safety threshold, the controller controls the first switches corresponding to the multiple battery packs to close and the second switches corresponding to the multiple battery packs to open, and closes the third switch; controls the multiple battery packs to supply power to the external device through the first bus line simultaneously.

[0015] In one implementation, both the first bus line and the second bus line are bus bars.

[0016] In a second aspect, the present application provides an electronic device, including the multi-battery-pack parallel control circuit according to any one of the above implementations.

[0017] In a third aspect, the present application provides an energy storage system, including the multi-battery-pack parallel control circuit according to any one of the above implementations.

[0018] Compared with the prior art, the present utility model has at least the following beneficial effects:

[0019] 1. By connecting the battery pack entering the charging state to the second bus line, the DC converter is started, and the battery pack entering the charging state is charged from the first bus line through the DC converter, thereby keeping the power difference between each battery pack relatively balanced and effectively avoiding the circulating current problem caused by direct parallel connection of each battery pack. At the same time, when each battery pack is connected in parallel to supply power to an external device, if one battery pack is damaged, it does not affect the other battery packs to supply power to the external device, improving the compatibility of this circuit and the user experience.

[0020] 2. The controller obtains the voltage and SOC of each battery pack through the battery management system of each battery pack, and calculates the voltage difference and SOC difference between each battery pack. If there are battery packs with voltage differences or SOC differences exceeding the safety threshold among multiple battery packs, the controller determines that the battery packs exceeding the safety threshold enter the charging state. At this time, the controller issues a charging instruction to the battery management system of the battery pack entering the charging state, thereby controlling the second switch corresponding to the battery pack entering the charging state to close, and the first switch remains open; the controller issues a discharging instruction to the battery management system of the battery packs not entering the charging state, thereby controlling the first switch corresponding to the battery packs not entering the charging state to close, and the second switch remains open, so as to charge the battery pack entering the charging state until the voltage difference and SOC difference between the battery pack entering the charging state and the battery packs not entering the charging state are both within the safety threshold, then close the first switch corresponding to the battery pack entering the charging state and open the corresponding second switch. Thus, the circulating current problem caused by direct parallel connection of multiple battery packs can be avoided.

[0021] 3. For the situation where the voltage differences or SOC differences of multiple battery packs are both greater than the safety threshold, give priority to charging the battery pack entering the charging state with the largest voltage difference or SOC difference. After a certain time interval, re-detect the voltage differences or SOC differences between each battery pack and sort them, and repeat charging the battery pack entering the charging state with the largest voltage difference or SOC difference after each sorting, further improving the compatibility of this method and avoiding the circulating current problem caused by direct parallel connection of multiple battery packs. Description of the Drawings

[0022] The following will further illustrate the above characteristics, technical features, advantages and their implementation manners of the present invention in a clear and understandable manner in combination with the drawings and preferred embodiments.

[0023] Figure 1 Shows the structural diagram of a multi-battery-pack parallel control circuit provided by an embodiment of the present application.

[0024] Reference Signs:

[0025] Battery pack 100; first bus line 200; DC converter 300; second bus line 400; first switch 500; second switch 600; third switch 700 and controller 800. Detailed implementation mode

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation modes of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, and other implementation modes can also be obtained.

[0027] To make the drawings concise, only the parts related to the utility model are schematically shown in each drawing, and they do not represent the actual structure of the product. In addition, to make the drawings concise and easy to understand, in some drawings, components with the same structure or function are only schematically shown for one of them, or only one of them is marked. In this document, "one" not only means "only this one", but also means "more than one" situation.

[0028] It should also be further understood that the term "and / or" used in the description of the present application and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0029] In this document, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0030] In addition, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions, and cannot be understood as indicating or implying relative importance.

[0031] It should be noted that the above embodiments can be freely combined as needed. The above are only the preferred implementation modes of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

[0032] A new energy battery pack refers to combining individual battery cells (or battery cores) into modules in a specific way, and then integrating these modules into a complete battery system to meet the specific requirements of new energy applications. The battery pack design not only includes the battery cells themselves, but also involves multiple aspects such as the Battery Management System (BMS), thermal management system, mechanical structure, and electrical connection. Among them, the battery management system is responsible for functions such as voltage acquisition, current acquisition, temperature acquisition, the percentage of remaining battery charge (State of Charge, SOC, hereinafter collectively referred to as SOC) within the battery pack, and communication with external controllers.

[0033] In the actual application process, if a single battery pack cannot meet the required voltage or capacity, the battery pack system can be expanded by connecting more battery packs in series or in parallel. Connecting in series can increase the output voltage of the system, while connecting in parallel increases the output current or capacity of the system. The series connection method can be applied to scenarios such as energy storage systems, electric vehicles, high-voltage equipment power supply, and power conversion systems. The parallel connection method can be applied to the energy storage system in the photovoltaic power generation system, and the parallel connection of multiple battery packs has advantages such as increasing capacity, load balancing, system redundancy, easy expansion, and improving the compatibility of backend devices. Among them, the series connection method is commonly used in most energy storage and power applications at present, but the increase in the system output voltage brought by the series connection method may also cause the backend devices to be unusable. Therefore, in many scenarios, the parallel connection method may be a more suitable choice compared to the series connection method. The parallel connection method only increases the system capacity and does not impose a burden on the backend devices. It can be imagined that if multiple battery packs are directly connected in parallel, due to the differences in voltage and / or internal resistance between each battery pack, an unexpected circulating current will be formed between the battery packs, resulting in a circulating current problem between the battery packs. Therefore, in the embodiments of the present application, by detecting the voltage difference or SOC difference between each parallel-connected battery pack in real time and charging the battery pack with a voltage difference or SOC difference greater than the safety threshold, at least one of the following beneficial effects can be achieved: avoiding the circulating current problem caused by directly connecting multiple battery packs in parallel; or if one of the parallel-connected battery packs is damaged, the battery pack can be powered off without affecting the use of the entire circuit, improving the compatibility of the multi-battery-pack parallel control circuit.

[0034] The following is a description with reference to the drawings:

[0035] Refer to the attached Figure 1 , which shows the structural diagram of a multi-battery-pack parallel control circuit provided by the embodiments of the present application, as Figure 1As shown in the figure, the circuit includes: a plurality of battery packs 100, a first bus line 200, a DC converter 300, a second bus line 400, and a controller 800. The input end of the DC converter 300 is connected to the first bus line 200, and the output end of the DC converter 300 is connected to the second bus line 400; the plurality of battery packs 100 are connected to the first bus line 200 in parallel to supply power to external devices through the first bus line 200; the plurality of battery packs 100 are connected to the second bus line 400 in parallel and are connected to the DC converter 300 through the second bus line 400; the controller 800 is communicatively connected to the plurality of battery packs 100 respectively. Among them, there are many communication methods between the controller 800 and the plurality of battery packs 100, such as including but not limited to field bus, Ethernet, serial communication, CAN communication, power line communication, fiber optic communication, local area network, etc.

[0036] The first bus line 200 is used to collect the electrical energy of the plurality of battery packs 100 together and send it to the DC converter 300 for voltage conversion or send it to an external device for power supply. The second bus line 400 is used to send the electrical energy converted by the DC converter 300 to the battery packs in the plurality of battery packs 100 that enter the charging state for charging. The first bus line 200 and the second bus line 400 have the same functions, including collecting, distributing, and transmitting electrical energy. Therefore, electronic devices with the functions of collecting, distributing, and transmitting electrical energy can be adopted in the embodiments of the present application. For example, the first bus line 200 and the second bus line 400 include but are not limited to busbars, busbar systems, bus systems, distribution boards, terminal blocks, collectors, mother lines, power distribution units (PDUs), etc.

[0037] When there is no battery pack in the plurality of battery packs 100 that enters the charging state, the controller 800 is used to control the conduction between the plurality of battery packs 100 and the first bus line 200 so that the plurality of battery packs 100 supply power to external devices through the first bus line 200.

[0038] When there is a battery pack 100 in the charging state among multiple battery packs 100, the controller 800 is used to control the battery pack 100 in the charging state to conduct with the second bus line 400, control the battery packs 100 not in the charging state to conduct with the first bus line 200, and start the DC converter 300 at the same time, so that the electric energy in the first bus line 200 charges the battery pack 100 in the charging state through the DC converter 300. After the voltage and SOC are balanced between the battery pack 100 in the charging state and the remaining battery packs 100, control the battery pack 100 in the charging state to conduct with the first bus line 200 and disconnect from the second bus line 400, so that all battery packs 100 supply power to external devices.

[0039] In the embodiment of the present application, by connecting multiple battery packs in parallel on the first bus line and the second bus line, when there is a battery pack in the charging state among the multiple battery packs, by connecting the battery pack in the charging state to the second bus line and the remaining battery packs to the first bus line, and charging the battery pack in the charging state through the first bus line, the balance between the battery packs is completed, effectively avoiding the circulating current problem caused by directly connecting the battery packs in parallel. At the same time, when multiple battery packs are connected in parallel to supply power to external devices, if one of the battery packs is damaged, it does not affect the other battery packs to supply power to external devices, improving the compatibility of the circuit and the user experience.

[0040] In an embodiment of the present application, referring to the appendix Figure 1 , each of the multiple battery packs 100 includes a battery management system 110. The battery management system 110 is used to obtain the voltage and SOC of its own battery pack 100, and send the voltage and SOC to the controller 800 respectively; the controller 800 calculates the voltage difference and SOC difference between the multiple battery packs 100 based on the voltage and SOC of the multiple battery packs 100; the controller 800 determines that the battery pack 100 with the voltage difference or SOC difference exceeding the safety threshold enters the charging state according to whether the voltage difference and SOC difference are both within the safety threshold; the controller 800 controls the battery pack 100 in the charging state to conduct with the second bus line 400, and starts the DC converter 300 to charge the battery pack 100 in the charging state from the first bus line 200 through the DC converter 300.

[0041] Before multiple battery packs 100 supply power to an external device, the controller 800 receives the voltages and SOCs of the multiple battery packs 100, and calculates the voltage differences and SOC differences between the multiple battery packs 100. The controller 800 determines whether both the voltage differences and SOC differences between the multiple battery packs are within the safety thresholds. If there are battery packs 100 among the multiple battery packs 100 whose voltage differences or SOC differences exceed the safety thresholds, the controller 800 determines that the battery packs 100 that exceed the safety thresholds enter the charging state. At the same time, the controller issues a discharging instruction to the battery management systems of the battery packs 100 that do not enter the charging state, and then controls the battery packs 100 that do not enter the charging state to conduct with the first bus line 200; the controller 800 issues a charging instruction to the battery management systems of the battery packs 100 that enter the charging state, and then controls the battery packs 100 that enter the charging state to conduct with the second bus line 400 and disconnect from the first bus line 200. The controller 800 also controls the DC converter 300 to start. At this time, the electric energy released by the battery packs 100 that do not enter the charging state enters the DC converter 300 through the first bus line 200 for voltage conversion, and the DC converter 300 outputs the electric energy after voltage conversion to the battery packs 100 that enter the charging state through the second bus line 400 for charging. The controller 800 continuously detects the power difference or SOC difference between the battery packs 100 that enter the charging state and the battery packs 100 that do not enter the charging state. When the power difference or SOC difference between the battery packs 100 that enter the charging state and the battery packs 100 that do not enter the charging state is within the safety thresholds, the controller 800 controls the battery packs 100 that do not enter the charging state to stop charging the battery packs 100 that enter the charging state, and the controller 800 controls the battery packs 100 that enter the charging state to conduct with the first bus line 200 and disconnect from the second bus line 400. So that the battery packs 100 that enter the charging state and the battery packs 100 that do not enter the charging state supply power to the external device.

[0042] In an embodiment of the present application, with reference to the attached Figure 1 , the multi-battery-pack parallel control circuit further includes a third switch 700. Wherein, one end of the third switch 700 is connected to the first bus line 200, and the other end is connected to the external device.

[0043] In some embodiments of the present application, with reference to the attached Figure 1 , the multi-battery-pack parallel control circuit further includes a plurality of first switches 500 and a plurality of second switches 600. Wherein, the plurality of first switches 500 correspond to the plurality of battery packs 100 one by one, and one end of each first switch is connected to the corresponding battery pack 100, and the other end is connected to the first bus line 200; the plurality of second switches 600 correspond to the plurality of battery packs 100 one by one, and one end of each second switch is connected to the corresponding battery pack 100, and the other end is connected to the second bus line 400.

[0044] Accordingly, the battery pack 100 is electrically connected to and disconnected from the first bus line 200 and the second bus line 400 through the corresponding first switch 500 and second switch 600 respectively. When the battery pack 100 not in the charging state needs to be electrically connected to the first bus line 200, the controller 800 controls the corresponding first switch 500 of the battery pack 100 not in the charging state to close, and the corresponding second switch 600 to remain open; when the battery pack 100 in the charging state needs to be electrically connected to the second bus line 400, the controller 800 controls the corresponding second switch 600 of the battery pack 100 in the charging state to close, and the corresponding first switch 500 to remain open.

[0045] In an embodiment of the present application, with reference to the attached Figure 1 It further includes: the controller 800 controls the battery pack 100 in the charging state to disconnect its corresponding first switch 500 and close its corresponding second switch 600, so that the DC converter 300 converts electrical energy from the first bus line 200 to charge the battery pack 100 in the charging state until the voltage difference and SOC difference between the battery pack 100 in the charging state and other battery packs 100 are both within the safety threshold, then disconnects its corresponding second switch 600 and closes its corresponding first switch 500.

[0046] The controller 800 obtains the voltage or SOC of each battery pack 100 through the battery management system 110 of each battery pack 100, and calculates the voltage difference or SOC difference between each battery pack 100. If there is a battery pack 100 among multiple battery packs 100 whose voltage difference or SOC difference exceeds the safety threshold, the controller 800 determines that the battery pack 100 exceeding the safety threshold enters the charging state. At this time, the controller 800 issues a charging instruction to the battery management system of the battery pack 100 in the charging state, thereby controlling the corresponding second switch 600 of the battery pack 100 in the charging state to close, and the first switch 500 to remain open; the controller 800 issues a discharging instruction to the battery management system of the battery pack 100 not in the charging state, thereby controlling the corresponding first switch 500 of the battery pack 100 not in the charging state to close, and the second switch 600 to remain open. The electrical energy of the battery pack 100 not in the charging state sequentially passes through the first bus line 200, the DC converter 300 and the second bus line 400 to charge the battery pack 100 in the charging state until the voltage difference and SOC difference between the battery pack 100 in the charging state and the battery pack 100 not in the charging state are both within the safety threshold, then closes the corresponding first switch 500 of the battery pack 100 in the charging state and disconnects the corresponding second switch 600. In this way, the circulating current problem caused by directly paralleling multiple battery packs can be avoided.

[0047] In an embodiment of the present application, there may be a situation where multiple battery packs 100 enter the charging state among multiple battery packs 100. For example, referring to the attached Figure 1 , the multi-battery-pack parallel control circuit further includes:

[0048] If there are multiple battery packs 100 among the multiple battery packs 100 whose voltage differences or SOC differences are greater than the safety threshold, the controller 800 sorts them according to the magnitude of the voltage difference or SOC difference, and preferentially arranges the battery pack 100 with the largest difference to enter the charging state.

[0049] The controller 800 re-detects the voltage differences and SOC differences of the multiple battery packs 100 at regular time intervals, and re-adjusts the order in which the battery packs 100 enter the charging state according to the magnitude of the differences until the voltage differences and SOC differences of the multiple battery packs 100 are both within the safety threshold.

[0050] When the controller 800 detects that there are multiple battery packs 100 among the multiple battery packs 100 whose voltage differences or SOC differences are greater than the safety threshold, the controller 800 determines that the battery packs 100 with voltage differences or SOC differences greater than the safety threshold enter the charging state. The controller 800 will sort according to the voltage difference or SOC difference between the multiple battery packs 100 that enter the charging state, and preferentially charge the battery pack 100 that enters the charging state with the largest difference. The cooperation relationship between the switches has been elaborated in detail in the foregoing embodiments. The controller 800 re-detects the voltage differences or SOC differences between the multiple battery packs 100 at regular time intervals. When the re-detected voltage differences or SOC differences are both greater than the safety threshold, the battery packs 100 that enter the charging state are sorted again according to the re-detected voltage differences or SOC differences, and the battery pack 100 that enters the charging state with the largest difference after the re-sorting is charged. The foregoing process is continuously repeated until the voltage differences or SOC differences between all battery packs 100 are within the safety threshold. Thus, for the situation where the voltage differences or SOC differences of multiple battery packs are both greater than the safety threshold, the battery pack that enters the charging state with the largest voltage difference or SOC difference is preferentially charged. After a certain time interval, the voltage differences or SOC differences between each battery pack are re-detected and sorted, and the battery pack that enters the charging state with the largest voltage difference or SOC difference after each sorting is repeatedly charged, which further improves the compatibility of the method and avoids the circulating current problem caused by directly paralleling multiple battery packs.

[0051] In an embodiment of the present application, referring to the attached Figure 1 , the multi-battery-pack parallel control circuit further includes:

[0052] When there is no battery pack 100 with a voltage difference or SOC difference greater than the safety threshold among multiple battery packs 100, the controller 800 controls the closing of the first switches 500 corresponding to the multiple battery packs 100, the opening of the second switches 600 corresponding to the multiple battery packs 100, and the closing of the third switch connected to the first bus line.

[0053] Control the multiple battery packs 100 to supply power to external devices simultaneously through the first bus line.

[0054] When the controller 800 detects that the voltage difference or SOC difference among the multiple battery packs 100 is less than the safety threshold, it controls the closing of the first switches 500 corresponding to the multiple battery packs 100, the opening of the corresponding second switches 600, and the closing of the third switch 700, so that the multiple battery packs 100 supply power to external devices simultaneously through the first bus line 200.

[0055] In some embodiments of the present application, both the first bus line 200 and the second bus line 400 are busbars.

[0056] The embodiments of the present application further provide an electronic device, including any one of the multi-battery-pack parallel control circuits in the above embodiments.

[0057] It should be noted that the above embodiments can be freely combined as needed. The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A multi-battery-pack parallel control circuit, characterized in that Including: Multiple battery packs, a first busbar line, a second busbar line, a DC converter, and a controller; The input end of the DC converter is connected to the first busbar line, and the output end of the DC converter is connected to the second busbar line; Multiple of the battery packs are connected to the first busbar line in parallel and supply power to external devices through the first busbar line; Multiple of the battery packs are connected to the second busbar line in parallel and are connected to the DC converter through the second busbar line; The controller is communicatively connected to multiple of the battery packs respectively.

2. The multi-battery-pack parallel control circuit according to claim 1, characterized in that Multiple of the battery packs each include a battery management system, and the battery management system is used to obtain the voltage and SOC of its respective battery pack and send the voltage and the SOC to the controller respectively; The controller calculates the voltage difference and the SOC difference between multiple of the battery packs based on the voltage and SOC of multiple of the battery packs; The controller determines that the battery pack with the voltage difference or the SOC difference exceeding the safety threshold enters the charging state according to whether both the voltage difference and the SOC difference are within the safety threshold; The controller controls the battery pack entering the charging state to conduct with the second busbar line, and starts the DC converter to charge the battery pack entering the charging state from the first busbar line through the DC converter.

3. The multi-battery-pack parallel control circuit according to claim 2, wherein It further includes: Multiple first switches, multiple second switches; Multiple of the first switches correspond to multiple of the battery packs one by one, and one end of each of the first switches is connected to the corresponding battery pack, and the other end is connected to the first busbar line; Multiple of the second switches correspond to multiple of the battery packs one by one, and one end of each of the second switches is connected to the corresponding battery pack, and the other end is connected to the second busbar line.

4. The multi-battery-pack parallel control circuit according to claim 3, wherein the controller controls the battery pack entering the charging state to be conducted with the second bus line, and starts the DC converter, and charges the battery pack entering the charging state from the first bus line through the DC converter. It is characterized in that, It further includes: The controller controls the battery pack entering the charging state to disconnect its corresponding first switch and close its corresponding second switch, so that the DC converter converts electrical energy from the first busbar line to charge the battery pack entering the charging state until the voltage difference and the SOC difference between the battery pack entering the charging state and other battery packs are both within the safety threshold, then disconnects its corresponding second switch and closes its corresponding first switch.

5. The multi-battery-pack parallel control circuit according to claim 4, wherein It further includes: If there are multiple battery packs with the voltage difference or the SOC difference greater than the safety threshold among multiple of the battery packs, the controller sorts them according to the magnitude of the difference in the voltage difference or the SOC difference, and preferentially arranges the battery pack with the largest difference to enter the charging state.

6. The multi-battery-pack parallel control circuit according to claim 5, wherein It further includes: The controller re-detects the voltage difference and the SOC difference of multiple of the battery packs at regular time intervals, and re-adjusts the order of the battery packs entering the charging state according to the magnitude of the difference until the voltage difference and the SOC difference of multiple of the battery packs are both within the safety threshold.

7. The multi-battery-pack parallel control circuit according to claim 3, characterized in that It further includes: A third switch, one end of the third switch is connected to the first busbar line, and the other end is connected to the external device.

8. The multi-battery-pack parallel control circuit according to claim 7, wherein It further includes: When there is no battery pack among the multiple battery packs with the voltage difference and the SOC difference greater than the safety threshold, the controller controls the first switches corresponding to the multiple battery packs to close, the second switches corresponding to the multiple battery packs to open, and the third switch to close; Control the multiple battery packs to supply power to the external device through the first bus line simultaneously.

9. The multi-battery-pack parallel control circuit according to any one of claims 1-8, characterized in that, Both the first bus line and the second bus line are busbars.

10. An electronic device, characterized in that, It includes the multi-battery-pack parallel control circuit according to any one of claims 1-9.

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