Charging and discharging control method, energy storage equipment and storage medium

Abstract

The invention discloses a charging and discharging control method, energy storage equipment and a storage medium, and is applied to the technical field of energy control. The charging and discharging control method is applied to the energy storage equipment, the energy storage equipment comprises a main battery pack and at least one power-up pack which are connected in parallel, the charging and discharging control method comprises the steps that the charging current and the discharging current of the energy storage equipment are obtained, the charging current is the sum of the charging current of the main battery pack and the charging current of each power-up pack, and the discharging current is the sum of the charging current of each power-up pack; the discharge current comprises the sum of the discharge current of the main battery pack and the discharge current of each power-up pack; under the condition that the energy storage equipment is charged and discharged at the same time, total current is determined based on the charging current and the discharging current; determining a first charging and discharging mode based on the total current; and switching the current working mode of the energy storage equipment into the first charging and discharging mode. The working mode is determined through the charging current and the discharging current, the response speed can be increased, and the hardware cost is reduced.

Description

Technical Field

[0001] The present application belongs to the field of energy control technology, and in particular relates to a charge and discharge control method, an energy storage device, and a non-transient computer-readable storage medium. Background Art

[0002] With the continuous advancement of science and technology, energy storage devices, as the core of the modern energy system, play a vital role in many aspects. They can serve as emergency power sources to ensure the power supply of critical equipment, promote energy accessibility, and optimize resource allocation. Controlling the charge and discharge of energy storage devices can ensure their safety and prevent serious accidents. It also improves energy efficiency, optimizes their service life, and reduces their operating costs.

[0003] In the prior art, control is performed through charge and discharge power, but there are problems such as slow dynamic response speed and high hardware cost. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art. To this end, this application proposes a charge and discharge control method, energy storage device, and non-transitory computer-readable storage medium that can improve the response speed of charge and discharge control and reduce the hardware cost of the energy storage device.

[0005] In a first aspect, the present application provides a charge and discharge control method, which is applied to an energy storage device, wherein the energy storage device includes multiple battery packs connected in parallel, wherein the multiple battery packs include a main battery pack and at least one power pack, and the charge and discharge control method includes:

[0006] Obtaining a charging current and a discharging current of the energy storage device, wherein the charging current includes the sum of the charging currents of the main battery pack and each power pack, and the discharging current includes the sum of the discharging currents of the main battery pack and each power pack;

[0007] When the energy storage device is charged and discharged simultaneously, determining a total current based on the charging current and the discharging current;

[0008] determining a first charge and discharge mode based on the total current;

[0009] The current operating mode of the energy storage device is switched to the first charge and discharge mode.

[0010] In a second aspect, the present application provides an energy storage device, comprising a main battery pack, at least one power pack, a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned charge and discharge control method when executing the computer program.

[0011] In a third aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which implements the above-mentioned charge and discharge control method when executed by a processor.

[0012] The charge and discharge control method, energy storage device, and non-transitory computer-readable storage medium provided in the embodiments of the present application perform charge and discharge switching based on the charging and discharging currents of the main battery pack and the charging and discharging currents of each power-up pack. This method can accurately determine the first charge and discharge mode of the energy storage device when the energy storage device is simultaneously charging and discharging. Furthermore, the current is an instantaneous variable, resulting in a fast response speed. Furthermore, only the current information of the energy storage device needs to be obtained, not information such as voltage. This can save hardware related to voltage detection and reduce the hardware cost of the energy storage device.

[0013] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0015] Figure 1 This is an application scenario diagram of the charge and discharge control method provided in an embodiment of the present application;

[0016] Figure 2 This is a first flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0017] Figure 3 This is a second flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0018] Figure 4 3 is a schematic diagram of a third flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0019] Figure 5 4 is a schematic diagram of a fourth flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0020] Figure 6 5 is a schematic diagram of a fifth flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0021] Figure 7 1 is a sixth flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0022] Figure 8 7 is a schematic diagram of a seventh flow chart of the charge and discharge control method provided in an embodiment of the present application;

[0023] Figure 9 This is a module schematic diagram of the charge and discharge control device provided in an embodiment of the present application;

[0024] Figure 10 It is a structural diagram of the energy storage device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The following describes embodiments of the present application in detail. Examples of the embodiments of the present application are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be understood as limiting the present application.

[0026] For ease of understanding, the following first introduces the technical background and application scenarios of this application:

[0027] Energy storage devices play a vital role in modern production and life. When the power grid fails due to failures, natural disasters, or other factors, energy storage devices can serve as a backup power source, ensuring the normal power supply of critical facilities (such as data center servers and communication base stations). Energy storage devices can also be charged with low-cost electricity and used during periods of high electricity prices, saving users money on electricity bills. Energy storage devices can also be used to release stored energy during peak electricity demand, reducing pressure on the power grid and avoiding the risk of voltage fluctuations or power outages caused by load surges.

[0028] Controlling the charge and discharge of energy storage devices is crucial for ensuring their safe, efficient, and long-term operation. This control prevents overcharging and over-discharging, protecting their safety. It also allows energy storage devices to charge with low-cost electricity and discharge when prices are high, optimizing energy utilization and reducing user electricity costs. This control also assists grid operations, serving as a backup power source to ensure critical loads operate in the event of a grid failure or outage, enhancing grid stability and improving power system reliability.

[0029] However, existing technologies use charge and discharge power for control when charging and discharging are performed simultaneously. When the charging power is greater than the discharging power, the energy storage device switches to charging mode; when the charging power is less than the discharging power, the energy storage device switches to discharging mode. This method is suitable for complex scenarios and has strong anti-interference capabilities. However, this method requires the calculation of charging and discharging power, and requires filtering or sliding averaging of the collected current and voltage to improve the accuracy and stability of power calculation.

[0030] Therefore, this method has a slow dynamic response speed and requires simultaneous acquisition of voltage and current, which requires more related hardware and results in higher hardware costs.

[0031] The charge and discharge control method provided in the present application performs charge and discharge switching through the charging and discharging currents of the main battery pack and the charging and discharging currents of each power pack. It can accurately determine the first charge and discharge mode of the energy storage device when the energy storage device is simultaneously charging and discharging. Furthermore, the current is an instantaneous variable and has a fast response speed. Furthermore, only the current information of the energy storage device needs to be obtained, and no information such as voltage is required. This can save hardware related to voltage detection and reduce the hardware cost of the energy storage device.

[0032] See also Figure 1 , Figure 1 1 is an application scenario diagram of a charge-discharge control method provided in an embodiment of the present application. The application scenario provided in the present application includes an energy storage device 100, which includes multiple battery packs 10 and a controller 20. The charge-discharge control method provided in the present application can be executed by the controller 20.

[0033] The battery pack 10 refers to an energy storage unit that can independently store and discharge energy. The battery pack 10 can be charged by a charging device and discharged to an electrical load. Multiple battery packs 10 include one main battery pack and multiple power packs. Multiple battery packs 10 are connected in parallel ( Figure 1 The example shows three battery packs 10 (one main battery pack and two power-up packs) connected in parallel, and a mixed connection of series and parallel is also possible. The same charging device can charge multiple battery packs 10 at the same time, and multiple battery packs 10 can also discharge to the same load at the same time.

[0034] Optionally, the battery pack 10 may be a lithium-ion battery pack, a lead-acid battery pack, a nickel-metal hydride battery pack, a solid-state battery pack, etc., which is not limited in the embodiment of the present application.

[0035] The battery pack 10 includes a battery module 11 , a charging switch circuit 12 , a discharging switch circuit 13 and a battery management system (BMS) 14 .

[0036] The battery module 11 is an independent functional unit composed of multiple single cells connected in series, parallel, or a combination of these. The battery module 11 can store and release energy and is connected to a charging switch circuit 12 and a discharging switch circuit 13. When the charging switch circuit 12 is on, the charger can charge the battery module 11; when the discharging switch circuit 13 is on, the battery module 11 can discharge energy to the load.

[0037] The type of the battery module 11 is consistent with the type of the battery pack 10. For example, when the battery pack 10 is a lithium-ion battery pack, the battery module 11 is also a lithium-ion battery module.

[0038] The charging switch circuit 12 is a circuit for controlling the charging process of the battery module 11. The input end of the charging switch circuit 12 is configured to be connected to a charging device, and the output end is connected to the battery module 11. When the charging switch circuit 12 is turned on, the charging device can charge the battery module 11.

[0039] The discharge switch circuit 13 is a circuit used to control the discharge process of the battery module 11. The input end of the discharge switch circuit 13 is connected to the battery module 11, and the output end is configured to be connected to an electrical load. When the discharge switch circuit 13 is turned on, the battery module 11 can discharge to the electrical load.

[0040] Among them, the battery management system 14 is a device used to detect the battery module 11 and realize charging and discharging control. The battery management system 141 is connected to the battery module 11 and can collect data such as the current and state of charge (SOC) of the battery module 11 in real time. The battery management systems 14 of each battery pack 10 can maintain a connection (such as via a CAN data line) to communicate with each other. The battery management system 14 is also connected to the charging switch circuit 12 and the discharging switch circuit 13 respectively, and controls the conduction and disconnection of the charging switch circuit 12 and the discharging switch circuit 13 respectively.

[0041] Optionally, the charging switch circuit 12 and the discharging switch circuit 13 may be MOS tube switch circuits, insulated gate bipolar transistor (IGBT) switch circuits, relay switch circuits, etc., respectively, which is not limited in the embodiment of the present application.

[0042] The controller 20 is a device with data processing capabilities. The controller 20 is connected to the battery management system 14 of each battery pack 10 (e.g., via a CAN data line), receives and analyzes data collected by each battery management system 14, and can also send corresponding instructions to each battery management system 14 to enable each battery management system 14 to control the charging and discharging process of the corresponding battery pack 10.

[0043] Optionally, the controller 20 may also display data collected by each battery management system 14 (such as current, SOC, etc.).

[0044] Optionally, the controller 20 can be a CAN host computer, a microcontroller unit (MCU), a combination of an MCU and a display, a single-chip microcomputer, a system on a chip (SoC), a field programmable gate array (FPGA), etc., which is not limited to the embodiments of the present application.

[0045] Based on the above technical background and the introduction of related scenarios, the embodiment of the present application provides a charge and discharge control method, which is described in detail below:

[0046] See also Figure 2 A charge and discharge control method provided in an embodiment of the present application is implemented by step 011, step 012, step 013 and step 014, which are described in detail below.

[0047] Step 011: Obtain the charging current and discharging current of the energy storage device;

[0048] Step 012: When the energy storage device is simultaneously charging and discharging, determine the total current based on the charging current and the discharging current;

[0049] Step 013: Determine a first charge and discharge mode based on the total current;

[0050] Step 014: Switch the current operating mode of the energy storage device to the first charge and discharge mode.

[0051] Among them, the charging current refers to the sum of the charging currents of the main battery pack and each power pack in the energy storage device; the discharging current refers to the sum of the discharging currents of the main battery pack and each power pack in the energy storage device.

[0052] When the charging current is AC, the value of the charging current is calculated using the effective value of the AC; similarly, when the discharging current is AC, the value of the discharging current is calculated using the effective value of the AC.

[0053] The total current is a value representing the total current condition of the energy storage device.

[0054] The first charge-discharge mode refers to the primary mode when the energy storage device is simultaneously charging and discharging. The first charge-discharge mode includes a charging mode and a discharging mode. The charging mode is an operating mode in which the energy storage device receives electricity and not only supplies power to the load, but also charges the energy storage device. The discharging mode is an operating mode in which the energy storage device receives electricity and supplies power to the load, while also consuming the energy storage device's own power to power the load.

[0055] Specifically, by communicating with the BMS of each battery pack (main battery pack and charging pack), the charging current and discharging current of the corresponding battery pack obtained by each BMS are obtained. When the energy storage device is connected to the charging device and the electrical load at the same time, the energy storage device is charged by the charging device and discharged to the electrical load at the same time. In this case, based on the determined charging current and discharging current, the total current can be determined by setting different positive and negative values ​​for the charging current and the discharging current, or by assigning different vectors to the charging current and the discharging current, and then summing them to obtain the total current.

[0056] Based on the specific value of the total current, the first charge and discharge mode of the energy storage device can be determined. The current operating mode of the energy storage device can be promptly switched to the determined first charge and discharge mode, which can improve the stability and safety of the energy storage device, increase energy utilization, and extend the service life of the energy storage device.

[0057] Moreover, the method only needs to obtain current, which can reduce the hardware components for collecting data such as voltage and reduce hardware costs.

[0058] In some embodiments, when the energy storage device switches its operating mode, it is necessary to determine the temperature condition and the fault condition. The operating mode can only be switched when the temperature of the energy storage device is greater than a first preset temperature (e.g., 5°C). When the first charge and discharge mode is the charging mode, the fault condition must be that there is no charging warning before the operating mode can be switched; when the first charge and discharge mode is the discharge mode, the fault condition must be that there is no discharge warning before the operating mode can be switched.

[0059] The temperature of the energy storage device is determined based on the battery temperature collected by the BMS of each battery pack, for example, it can be the average value or minimum value of the temperature of each battery.

[0060] Among them, the charge warning and discharge warning are information generated by the BMS of each battery pack based on the collected data.

[0061] In this way, the risks of charging and discharging can be avoided and the safety of energy storage equipment can be improved.

[0062] In some embodiments, the current operating mode of the energy storage device is determined as follows.

[0063] When the multiple battery packs of the energy storage device are divided into a main battery pack and multiple power-up packs, when a power-up pack is received and connected to the main battery pack in parallel, the controller (or the BMS of the main battery pack) pulls up the internal dedicated hardware IO to indicate that the power-up pack is connected, and then the BMS of the newly connected power-up pack sends a CAN message of the power-up pack access event to the controller (or the BMS of the main battery pack). After receiving the message, the controller (or the BMS of the main battery pack) will address the newly connected power-up pack and modify the address of each power-up pack in sequence according to the access order, so that after the power-up pack is connected, the controller (or the BMS of the main battery pack) can control the main battery pack and each power-up pack.

[0064] Add a variable of the state machine mode. Each time the charge and discharge state is switched, this variable will be assigned a value, and the variable of the state machine mode will be changed. The working mode can be determined by judging the variable of the state machine mode.

[0065] After addressing of each battery pack is completed, the mode flag is 0, and the charging switch circuit and the discharging switch circuit of each battery pack are not controlled; when the energy storage device is switched to charging mode, the mode flag is 1, and the charging switch circuit and the discharging switch circuit of each battery pack are controlled accordingly; when the energy storage device is switched to discharging mode, the mode flag is 2, and the charging switch circuit and the discharging switch circuit of each battery pack are controlled accordingly.

[0066] In some embodiments, see Figure 3 Optionally, step 012 includes:

[0067] Step 0121: Determine the total current as the sum of the charging current and the discharging current.

[0068] Specifically, when the charging current is set to a negative value and the discharging current is set to a positive value, the sum of the values ​​of the charging current and the discharging current is taken as the value of the total current.

[0069] For example, when the energy storage device includes 4 battery packs, the charging currents of two battery packs are 5A and 10A respectively, and the discharge currents of the two battery packs are both 5A, the charging current 15A takes a negative value of -15A, and the discharge current 10A takes a positive value of 10A, and the total current is -15A+10A=-5A.

[0070] In some embodiments, see Figure 3 Optionally, step 012 includes:

[0071] Step 0122: Determine the total current based on the absolute value of the difference between the charging current and the discharging current, and the magnitude relationship between the charging current and the discharging current.

[0072] Specifically, when the charging current is greater than the discharging current, the total current is a negative value, which is the absolute value of the difference between the charging current and the discharging current; when the charging current is less than the discharging current, the total current is a positive value, which is the absolute value of the difference between the charging current and the discharging current; when the charging current is equal to the discharging current, the total current is zero.

[0073] For example, when the energy storage device includes 4 battery packs, the charging currents of two battery packs are both 5A, and the discharge currents of the two battery packs are 5A and 10A respectively, the difference between the charging current 10A and the discharge current 15A is 5A, and the absolute value of the difference 5A is 5A. The charging current is less than the discharge current, and the total current is a positive value of 5A.

[0074] In some embodiments, see Figure 3 Optionally, step 013 includes:

[0075] Step 0131: when the total current is less than a first preset current threshold, determining that the first charge-discharge mode is a charging mode, and the first preset current threshold is less than 0;

[0076] Step 0132: When the total current is greater than the second preset current threshold, determining that the first charge-discharge mode is the discharge mode, and the second preset current threshold is greater than 0;

[0077] Step 0133: When the total current is between the first preset current threshold and the second preset current threshold, determine that the first charge and discharge mode is the current operating mode.

[0078] The first preset current threshold and the second preset current threshold are both current values ​​set based on experience, and are positively correlated with the number of power packs (or battery packs).

[0079] Specifically, when each battery pack is divided into a main battery pack and a booster pack, the sampling accuracy of the BMS of the main battery pack and the booster pack is limited. For example, if the energy storage device originally includes three battery packs (or one main battery pack and two booster packs), and two new battery packs (or two booster packs) are added to meet usage requirements, the absolute values ​​of the corresponding first and second preset current thresholds should be set to larger values ​​to reduce the impact of multiple battery packs on the sampling accuracy.

[0080] Therefore, by setting the first preset current threshold and the second preset current threshold, the risk of misjudgment of the total current due to insufficient BMS sampling accuracy can be reduced, and the stability of the energy storage device can be improved.

[0081] Specifically, the first preset current threshold is less than 0, and the second preset current threshold is greater than 0. Therefore, when the total current is greater than (or equal to) the first preset current threshold and less than (or equal to) the second preset current threshold, the energy storage device maintains the current operating mode as the first charge and discharge mode, which can maintain the stability of the energy storage device and avoid frequent switching that increases the wear of electronic components inside the energy storage device, thereby extending the service life of the energy storage device.

[0082] In some embodiments, see Figure 4 Optionally, step 0131 includes step 01311, and step 0132 includes step 01321, as described in detail below.

[0083] Step 01311: When the total current within the first preset time period is less than the first preset current threshold, determining that the first charge-discharge mode is the charging mode;

[0084] Step 01321: When the total current within the second preset time period is greater than the second preset current threshold, determine that the first charge and discharge mode is the discharge mode.

[0085] Wherein, the first preset duration and the second preset duration are both time lengths set based on experience. Optionally, the first preset duration and the second preset duration can be the same value (such as 10 seconds), or different values.

[0086] Specifically, when the total current value is stable, determining the first charge and discharge mode and switching it can avoid frequent switching that increases wear on electronic components inside the energy storage device, thereby extending the service life of the energy storage device.

[0087] In some embodiments, see Figure 5 The charge and discharge control method also includes step 015, step 016 and step 017, which are described in detail below.

[0088] Step 015: When the energy storage device is being charged but not being discharged, determining that the current operating mode of the energy storage device is a charging mode;

[0089] Step 016: When the energy storage device is discharging but not charging, determining that the current operating mode of the energy storage device is a discharging mode;

[0090] Step 017: When the energy storage device is not charging or discharging, determine that the current working mode of the energy storage device is the standby mode. In the standby mode, the charging switch circuit and the discharging switch circuit of each battery pack of the energy storage device are disconnected.

[0091] Specifically, the operating status of the energy storage device is detected at regular intervals (e.g., 100 milliseconds) to determine whether the energy storage device is charging or discharging. Based on the operating status of the energy storage device, the current operating mode of the energy storage device can be determined accordingly. If the energy storage device is simultaneously charging and discharging, the first charge / discharge mode of the energy storage device is determined.

[0092] Optionally, when the energy storage device is not charging or discharging, the current operating mode of the energy storage device can be determined to be pre-discharge mode. In pre-discharge mode, the charging switch circuit of each battery pack of the energy storage device is disconnected, and the discharge switch circuit is turned on. This allows the BMS to remain powered on, monitor the battery modules in real time, and promptly detect abnormal conditions (such as excessive temperature). At the same time, it maintains low-power wake-up capabilities and promptly responds to the power needs of the load.

[0093] When the energy storage device is in standby mode, the charging switch circuit and the discharging switch circuit of each battery pack are disconnected through the BMS of each battery pack, which can cut off the current path, achieve electrical isolation, reduce the switching loss in the charging switch circuit and the discharging switch circuit, and improve the safety of the energy storage device.

[0094] In some embodiments, see Figure 5 The charge and discharge control method also includes step 018, which is described in detail below.

[0095] Step 018: Based on the current operating mode of the energy storage device and the remaining power of each battery pack, determine the second charge and discharge mode of each battery pack.

[0096] The remaining capacity refers to the state of charge of the battery pack, that is, the SOC of the battery pack, which is expressed as a percentage.

[0097] The second charge and discharge mode refers to a specific operating mode of the battery pack in the energy storage device.

[0098] Specifically, when the energy storage device includes multiple battery packs connected in parallel, the second charge and discharge mode of the corresponding battery pack is determined based on the current operating mode and the remaining power of each battery pack. For example, when the current operating mode is charging mode, the battery pack(s) with the lowest remaining power are prioritized for charging; when the current operating mode is discharging mode, the battery pack(s) with the highest remaining power are prioritized for discharging.

[0099] In this way, overcharging or over-discharging of each battery pack can be avoided, the safety and service life of each battery pack can be guaranteed, and the differences in the remaining power of each battery pack can be balanced, which can improve the consistency of the energy storage equipment and improve energy utilization.

[0100] In some embodiments, see Figure 6 Optionally, step 018 includes:

[0101] Step 0181: sorting the battery packs based on their remaining power;

[0102] Specifically, when the number of battery packs in the energy storage device is greater than 2, corresponding second charge and discharge modes are set for battery packs with different remaining power rankings according to the current working mode of the energy storage device to avoid overcharging or over-discharging of the battery packs and protect the safety of each battery pack.

[0103] Optionally, multiple sorting ranges may be set to finely manage the second charge and discharge mode of each battery pack.

[0104] Step 0182: When the first charge / discharge mode is the charge mode, determine, among the plurality of battery packs, that the second charge / discharge mode of the battery packs within a first sorting range is the charge mode, the second charge / discharge mode of the battery packs within a second sorting range is the pre-charge mode, and the second charge / discharge mode of the battery packs within a third sorting range is the standby mode, with the first sorting range, the second sorting range, and the third sorting range increasing in sequence;

[0105] Among them, in charging mode, the charging switch circuit and the discharging switch circuit of the battery pack are both turned on; in pre-charging mode, the charging switch circuit of the battery pack is turned on and the discharging switch circuit is turned off; in standby mode, the charging switch circuit and the discharging switch circuit of the battery pack are both turned off.

[0106] Among them, the first sorting range, the second sorting range, and the third sorting range are all numerical ranges of remaining power set based on experience. For example, the first sorting range can be set to 0%-30%, the second sorting range can be set to 30%-70%, and the third sorting range can be set to 70%-100%. The first sorting range, the second sorting range, and the third sorting range can cover 0%-100%, or they can cover the part of 0%-100%, and the remaining part can be set with corresponding strategies (such as stopping discharge if it is less than 5%).

[0107] Specifically, when the first charge / discharge mode is the charging mode, three sorting ranges are set, each corresponding to a different second charge / discharge mode. By dividing each battery pack into a corresponding sorting range based on the remaining charge, and setting the corresponding second charge / discharge mode, the remaining charge differences between the battery packs can be balanced, improving energy utilization and extending the service life of each battery pack and the energy storage device.

[0108] For example, the first sorting range is 0%-30%, the second sorting range is 30%-70%, and the third sorting range is 70%-100%. The energy storage device includes three battery packs, which are divided into one main battery pack and two power-up packs. The remaining charge of the main battery pack is 65%, and the remaining charges of the two power-up packs are 20% and 83%, respectively. If the first charge and discharge mode of the energy storage device is charging mode, the power-up pack with a remaining charge of 20% is in the first sorting range, and its second charge and discharge mode is charging mode; the main battery pack with a remaining charge of 65% is in the second sorting range, and its second charge and discharge mode is standby mode; the power-up pack with a remaining charge of 83% is in the third sorting range, and its second charge and discharge mode is standby mode.

[0109] Each second charge and discharge mode corresponds to setting the on and off conditions of the charging switch circuit and the discharging switch circuit, which can avoid abnormal current paths, reduce failure risks and energy loss, and increase the service life of each battery pack.

[0110] In some embodiments, see Figure 6 Optionally, step 018 includes:

[0111] Step 0183: When the first charge-discharge mode is the charge mode, determine, among the multiple battery packs, that the second charge-discharge mode of the battery pack with the lower remaining power is the charge mode and the second charge-discharge mode of the battery pack with the higher remaining power is the pre-charge mode;

[0112] Among them, in the charging mode, the charging switch circuit and the discharging switch circuit of the battery pack are both turned on; in the pre-charging mode, the charging switch circuit of the battery pack is turned on and the discharging switch circuit is turned off.

[0113] Specifically, when the number of battery packs in the energy storage device is 2 and the first charge and discharge mode is the charging mode, the charging mode and the pre-charging mode are set for the two battery packs respectively by comparing the remaining power.

[0114] This can balance the remaining power of the two battery packs, reduce the risk of overcharging, and improve the safety and service life of the battery pack.

[0115] In some embodiments, see Figure 6 Optionally, step 018 includes:

[0116] Step 0184: When the remaining power of any target battery pack within the first sorting range is consistent with the remaining power of a battery pack within the second sorting range, switch the second charge and discharge mode of the battery pack consistent with the remaining power of the target battery pack to the charging mode.

[0117] The target battery pack refers to a battery pack that was originally in the first sorting range and is being charged, and whose remaining power has increased to the same level as the remaining power of the battery packs in the second sorting range.

[0118] Optionally, the consistency of the remaining power means that the remaining power is equal, or the difference between the remaining power is less than a preset power difference, or the voltages of the two battery packs are equal (or the voltage difference is less than a preset voltage difference such as 0.7V).

[0119] Specifically, the target battery pack is charged, and the remaining charge increases. If the remaining charge of the target battery pack remains within the first sorting range, charging continues. If the remaining charge of the target battery pack remains within the second sorting range, two situations may occur: if the remaining charge of the target battery pack is still less than the remaining charge of any battery pack in the original second sorting range, the battery packs in the first sorting range and the target battery pack are charged; if the remaining charge of the target battery pack matches the remaining charge of any battery pack in the original second sorting range, the second charge-discharge mode of the battery pack that matches the remaining charge of the target battery pack is switched to the charging mode, and this battery pack is also charged.

[0120] In this way, the remaining power of the battery pack can be balanced, the risk of overcharging can be reduced, and the safety and service life of the battery pack can be improved.

[0121] In some embodiments, see Figure 7 Optionally, step 018 includes:

[0122] Step 0185: When the first charge and discharge mode is the discharge mode, determine, among the multiple battery packs, that the second charge and discharge mode of the battery packs in the fourth sorting range is the discharge mode, the second charge and discharge mode of the battery packs in the fifth sorting range is the pre-discharge mode, and the second charge and discharge mode of the battery packs in the sixth sorting range is the standby mode, with the fourth sorting range, the fifth sorting range, and the sixth sorting range decreasing in order;

[0123] Among them, in the discharge mode, the charging switch circuit and the discharge switch circuit of the battery pack are both turned on; in the pre-discharge mode, the charging switch circuit of the battery pack is disconnected and the discharge switch circuit is turned on; in the standby mode, the charging switch circuit and the discharge switch circuit of the battery pack are both disconnected.

[0124] The fourth, fifth, and sixth sorting ranges are all numerical ranges of remaining power set based on experience. For example, the fourth sorting range can be set to 70%-100%, the fifth sorting range to 30%-70%, and the sixth sorting range to 0%-30%. The fourth, fifth, and sixth sorting ranges can cover 0%-100%, or they can cover only the portion of 0%-100%, with a corresponding policy set for the remaining portion (e.g., stop charging if the battery exceeds 95%).

[0125] Specifically, if the number of battery packs in the energy storage device is greater than two and the first charge / discharge mode is discharge mode, three sorting ranges are set, each corresponding to a different second charge / discharge mode. By sorting each battery pack into a corresponding sorting range based on the remaining charge, and setting the corresponding second charge / discharge mode, the remaining charge differences between the battery packs can be balanced, improving energy utilization and extending the service life of each battery pack and the energy storage device.

[0126] Each second charge and discharge mode corresponds to setting the on and off conditions of the charging switch circuit and the discharging switch circuit, which can avoid abnormal current paths, reduce failure risks and energy loss, and increase the service life of each battery pack.

[0127] In some embodiments, see Figure 7 Optionally, step 018 includes:

[0128] Step 0186: When the first charge-discharge mode is the discharge mode, determine, among the multiple battery packs, that the second charge-discharge mode of the battery pack with the lower remaining power is the discharge mode and the second charge-discharge mode of the battery pack with the higher remaining power is the pre-discharge mode;

[0129] Among them, in the discharge mode, the charging switch circuit and the discharge switch circuit of the battery pack are both turned on; in the pre-discharge mode, the charging switch circuit of the battery pack is disconnected and the discharge switch circuit is turned on.

[0130] Specifically, when the number of battery packs in the energy storage device is 2 and the first charge and discharge mode is the discharge mode, the discharge mode and the pre-discharge mode are set for the two battery packs respectively by comparing the remaining power.

[0131] This can balance the remaining power of the two battery packs, reduce the risk of over-discharge, and improve the safety and service life of the battery pack.

[0132] In some embodiments, see Figure 7 Optionally, step 018 includes:

[0133] Step 0187: When the remaining power of any target battery pack within the fourth sorting range is consistent with the remaining power of a battery pack within the fifth sorting range, switch the second charge and discharge mode of the battery pack consistent with the remaining power of the target battery pack to the discharge mode.

[0134] The target battery pack refers to a battery pack that was originally in the fourth sorting range and was discharged, and whose remaining power is reduced to the same level as the remaining power of the battery packs in the fifth sorting range.

[0135] Optionally, the consistency of the remaining power means that the remaining power is equal, or the difference between the remaining power is less than a preset power difference, or the voltages of the two battery packs are equal (or the voltage difference is less than a preset voltage difference such as 0.7V).

[0136] Specifically, the target battery pack is discharged, and the remaining charge decreases. If the remaining charge of the target battery pack is still within the fourth sorting range, the discharge continues. If the remaining charge of the target battery pack is within the fifth sorting range, there are two cases: if the remaining charge of the target battery pack is still greater than the remaining charge of any battery pack in the original fifth sorting range, the battery packs in the fourth sorting range and the target battery pack are discharged; if the remaining charge of the target battery pack is the same as the remaining charge of any battery pack in the original fifth sorting range, the second charge and discharge mode of the battery pack with the same remaining charge as the target battery pack is switched to the discharge mode, and the battery pack is also discharged.

[0137] In this way, the remaining power of the battery pack can be balanced, the risk of over-discharge can be reduced, and the safety and service life of the battery pack can be improved.

[0138] In some embodiments, see Figure 8 The charge and discharge control method also includes step 019 and step 020, which are described in detail below.

[0139] Step 019: When the remaining power of any battery pack is greater than a first power threshold, reducing the duty cycle of the charging switch circuit of the battery pack;

[0140] Step 020: When the remaining power of any battery pack is less than a second power threshold, reduce the duty cycle of the discharge switch circuit of the battery pack.

[0141] The first power threshold and the second power threshold are thresholds set based on experience. The first power threshold is greater than the second power threshold. Optionally, the first power threshold may be 5% and the second power threshold may be 95%.

[0142] Specifically, when the remaining power of the battery pack is too high or too low, reducing the duty cycle of the corresponding switching circuit through BMS control can reduce the risk of overcharging or over-discharging of the battery pack and extend the overall safety and service life of the energy storage device.

[0143] Optionally, reducing the duty cycle of the battery pack's charging switch circuit can be done by reducing it to 0, disconnecting the charging process and protecting the battery pack, or by reducing the duty cycle to less than a preset duty cycle, greatly delaying the increase in the remaining power of the battery pack, thereby avoiding overcharging and improving the safety and service life of the battery pack.

[0144] Similarly, reducing the duty cycle of the discharge switch circuit of the battery pack is similar to reducing the duty cycle of the charge switch circuit of the battery pack. To avoid repetition, it will not be described here. This can avoid over-discharge and improve the safety and service life of the battery pack.

[0145] According to the method described in the above embodiment, the present application also provides a charge and discharge control device for executing the steps in the above charge and discharge control method. Figure 9 , Figure 9 : is a module diagram of a charge and discharge control device 200 provided in an embodiment of the present application. The charge and discharge control device 200 includes:

[0146] An acquisition module 201 is configured to acquire the charging current and discharging current of the energy storage device, wherein the charging current includes the sum of the charging currents of the main battery pack and each power pack, and the discharging current includes the sum of the discharging currents of the main battery pack and each power pack;

[0147] A first determining module 202 is configured to determine a total current based on a charging current and a discharging current when the energy storage device is simultaneously charging and discharging;

[0148] A second determining module 203 is configured to determine a first charge and discharge mode based on the total current;

[0149] The execution module 204 is configured to switch the current operation mode of the energy storage device to the first charge and discharge mode.

[0150] It should be noted that the specific details of each module unit in the above-mentioned charge and discharge control device have been described in detail in the embodiment of the above-mentioned charge and discharge control method, and will not be repeated here.

[0151] In the embodiments of the present application, the term "module" or "unit" refers to a computer program or a part of a computer program that has a predetermined function and works together with other related parts to achieve a predetermined goal, and can be implemented in whole or in part by using software, hardware (such as processing circuits or memories) or a combination thereof. Similarly, a processor (or multiple processors or memories) can be used to implement one or more modules or units. In addition, each module or unit can be part of an overall module or unit that includes the function of the module or unit.

[0152] In some embodiments, the charge and discharge control device in the embodiments of the present application can be implemented in hardware, such as an energy storage device, or a component in the energy storage device, such as an integrated circuit or a chip; the charge and discharge control device can also be implemented in software, such as as an application installed in the energy storage device.

[0153] The present application also provides an energy storage device comprising a main battery pack, at least one power-up pack, a processor, a memory, and a computer program stored in the memory and executable on the processor. The main battery pack and the power-up packs are connected in parallel, and the processor controls the operation of the main battery pack and the power-up packs, respectively. When the processor executes the computer program, each process of the aforementioned charge and discharge control method embodiment is implemented, achieving the same technical effects. To avoid repetition, these processes are not described here.

[0154] In some embodiments, see Figure 10 , Figure 10 Schematic diagram of the structure of the energy storage device provided in an embodiment of the present application. The energy storage device 300 includes a main battery pack 301, at least one power-up pack 302, a processor 303, and a memory 304. The processor 303 is connected to the main battery pack 301 and the power-up pack 302, respectively, to control the operation of the main battery pack 301 and the power-up pack 302, respectively. The memory 304 stores a computer program 305 that can be run on the processor 303. When the program 305 is executed by the processor 303, it implements the various processes of the embodiment of the above-mentioned charge and discharge control method and can achieve the same technical effect. To avoid repetition, it will not be described here.

[0155] An embodiment of the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes of the embodiment of the above-mentioned charge and discharge control method are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0156] The processor may be the processor in the energy storage device in the above embodiment. The computer readable storage medium may be a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0157] Computer-readable media may include computer storage media and communication media. Computer storage media include volatile and non-volatile, removable and non-removable media implemented by any method or technology for storing information such as computer-readable instructions, data structures, program modules or other data. Computer storage media include RAM, ROM, Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), flash memory or other solid-state memory technology, CD-ROM, Digital Versatile Disc (DVD) or other optical storage, tape cassettes, magnetic tape, disk storage or other magnetic storage devices. Of course, those skilled in the art will appreciate that computer storage media are not limited to the above.

[0158] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the aforementioned charge-discharge control method. The processor may be a processor in the energy storage device described in the aforementioned embodiment. When executed by the processor, the computer program implements each of the processes described in the aforementioned charge-discharge control method embodiment, achieving the same technical effects. To avoid repetition, these processes are not described here.

[0159] It is understandable that in the specific implementation of this application, data related to user identity or characteristics is involved. When the above embodiments of this application are applied to specific products or technologies, user permission or consent is required, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0160] In the description of this specification, the reference terms "certain embodiments", "in an example", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are mutually inconsistent.

[0161] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0162] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A charge and discharge control method, characterized in that: Applied to an energy storage device, the energy storage device includes multiple battery packs connected in parallel, the multiple battery packs include a main battery pack and at least one power pack, the charge and discharge control method includes: Obtaining a charging current and a discharging current of the energy storage device, wherein the charging current includes the sum of the charging currents of the main battery pack and each power pack, and the discharging current includes the sum of the discharging currents of the main battery pack and each power pack; When the energy storage device is charged and discharged simultaneously, determining a total current based on the charging current and the discharging current; determining a first charge and discharge mode based on the total current; The current operating mode of the energy storage device is switched to the first charge and discharge mode.

2. The charge and discharge control method according to claim 1, wherein: The charging current is a negative value, the discharging current is a positive value, and determining the total current based on the charging current and the discharging current includes: The total current is determined to be the sum of the charging current and the discharging current.

3. The charge and discharge control method according to claim 1, wherein: The determining of the total current based on the charging current and the discharging current includes: The total current is determined based on an absolute value of a difference between the charging current and the discharging current and a magnitude relationship between the charging current and the discharging current.

4. The charge and discharge control method according to claim 2 or 3, characterized in that: The first charge and discharge mode includes a charge mode and a discharge mode, and determining the first charge and discharge mode based on the total current includes: When the total current is less than a first preset current threshold, determining that the first charge-discharge mode is a charging mode, and the first preset current threshold is less than 0; When the total current is greater than a second preset current threshold, determining that the first charge and discharge mode is a discharge mode, and the second preset current threshold is greater than 0; When the total current is between the first preset current threshold and the second preset current threshold, the first charge and discharge mode is determined to be the current operating mode.

5. The charge and discharge control method according to claim 4, wherein: The first preset current threshold and the second preset current threshold are both positively correlated with the number of power-up packs.

6. The charge and discharge control method according to claim 4, wherein: When the total current is less than a first preset current threshold, determining that the first charge-discharge mode is a charging mode includes: When the total current within the first preset time period is less than the first preset current threshold, determining that the first charge-discharge mode is the charging mode; When the total current is greater than a second preset current threshold, determining that the first charge-discharge mode is a discharge mode includes: When the total current within the second preset time period is greater than the second preset current threshold, the first charge and discharge mode is determined to be the discharge mode.

7. The charge and discharge control method according to claim 1, wherein: Also includes: When the energy storage device is being charged but not being discharged, determining that the current operating mode of the energy storage device is a charging mode; When the energy storage device is discharging but not charging, determining that the current operating mode of the energy storage device is a discharging mode; When the energy storage device is not charging or discharging, it is determined that the current working mode of the energy storage device is the standby mode. In the standby mode, the charging switch circuit and the discharging switch circuit of each battery pack of the energy storage device are disconnected.

8. The charge and discharge control method according to any one of claims 1 to 7, characterized in that: The energy storage device further includes a plurality of battery packs connected in parallel, and the charge and discharge control method further includes: Based on the current operating mode of the energy storage device and the remaining power of each battery pack, a second charge and discharge mode of each battery pack is determined respectively.

9. The charge and discharge control method according to claim 8, characterized in that: If the number of the battery packs is greater than 2, determining the second charge and discharge mode of each battery pack based on the operating mode of the energy storage device and the remaining power of each battery pack includes: sorting the battery packs based on the remaining power of the battery packs; When the first charge and discharge mode is the charge mode, determining, among the plurality of battery packs, that the second charge and discharge mode of the battery packs within a first sorting range is the charge mode, that the second charge and discharge mode of the battery packs within a second sorting range is the pre-charge mode, and that the second charge and discharge mode of the battery packs within a third sorting range is the standby mode, the first sorting range, the second sorting range, and the third sorting range increasing in sequence; Among them, in the charging mode, the charging switch circuit and the discharging switch circuit of the battery pack are both turned on; in the pre-charging mode, the charging switch circuit of the battery pack is turned on and the discharging switch circuit is turned off; in the standby mode, the charging switch circuit and the discharging switch circuit of the battery pack are both turned off.

10. The charge and discharge control method according to claim 9, wherein: The determining of the second charge and discharge mode of each battery pack based on the current operating mode of the energy storage device and the remaining power of each battery pack further includes: When the remaining power of any target battery pack within the first sorting range is consistent with the remaining power of the battery pack within the second sorting range, the second charge and discharge mode of the battery pack consistent with the remaining power of the target battery pack is switched to the charging mode.

11. The charge and discharge control method according to claim 8, wherein: If the number of the battery packs is greater than 2, determining the second charge and discharge mode of each battery pack based on the operating mode of the energy storage device and the remaining power of each battery pack includes: sorting the battery packs based on the remaining power of the battery packs; When the first charge and discharge mode is the discharge mode, determining that, among the plurality of battery packs, the second charge and discharge mode of the battery packs within a fourth sorting range is the discharge mode, the second charge and discharge mode of the battery packs within a fifth sorting range is the pre-discharge mode, and the second charge and discharge mode of the battery packs within a sixth sorting range is the standby mode, the fourth sorting range, the fifth sorting range, and the sixth sorting range decrease in order; Among them, in the discharge mode, the charging switch circuit and the discharge switch circuit of the battery pack are both turned on; in the pre-discharge mode, the charging switch circuit of the battery pack is disconnected and the discharge switch circuit is turned on; in the standby mode, the charging switch circuit and the discharge switch circuit of the battery pack are both disconnected.

12. The charge and discharge control method according to claim 11, wherein: The determining of the second charge and discharge mode of each battery pack based on the current operating mode of the energy storage device and the remaining power of each battery pack further includes: When the remaining power of any target battery pack within the fourth sorting range is consistent with the remaining power of the battery pack within the fifth sorting range, the second charge and discharge mode of the battery pack consistent with the remaining power of the target battery pack is switched to the discharge mode.

13. The charge and discharge control method according to claim 1, wherein: Also includes: When the remaining power of any of the battery packs is greater than a first power threshold, reducing the duty cycle of the charging switch circuit of the battery pack; When the remaining power of any of the battery packs is less than a second power threshold, the duty cycle of the discharge switch circuit of the battery pack is reduced.

14. An energy storage device, characterized in that: include: a main battery pack and at least one power-up pack; A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the charge and discharge control method according to any one of claims 1 to 13 when executing the program.

15. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the charge and discharge control method according to any one of claims 1 to 13 is implemented.

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