Energy storage system and discharge control method thereof, energy storage controller, and storage medium

Abstract

The present invention discloses an energy storage system and a discharge control method thereof, an energy storage controller, and a storage medium, wherein the discharge control method of the energy storage system comprises: when it is determined that the energy storage system has not reached a preset discharge cut-off condition, obtaining the actual discharge current of each battery pack; when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, updating the current discharge current limit of the energy storage system to the sum of the actual discharge currents of multiple battery packs, and gradually reducing the current discharge current limit of the energy storage system; in the process of gradually reducing the current discharge current limit of the energy storage system, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, taking the sum of the actual discharge current of each battery pack as the current discharge current limit of the energy storage system, thereby avoiding the problems of over-discharge and insufficient discharge power of the battery packs in the energy storage system and improving the discharge capacity of the energy storage system.

Description

Technical Field

[0001] The present invention relates to the technical field of battery charging and discharging, and in particular to a discharge control method of an energy storage system, a computer-readable storage medium, an energy storage controller and an energy storage system. Background Art

[0002] For an energy storage system with multiple battery packs connected in parallel, when the battery packs are almost discharged, if there are large differences between the battery packs (poor consistency), then if the system discharge current is set too low, the system will not be able to provide sufficient discharge power, resulting in weak discharge capacity at the end of the system discharge. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the first object of the present invention is to propose a discharge control method for an energy storage system, which continuously updates the current discharge current limit of the energy storage system according to the actual discharge condition of the battery pack, thereby avoiding the problem that the system cannot provide sufficient discharge power due to the system discharge current being set too low, and improving the discharge capacity of the system.

[0004] A second object of the present invention is to provide a computer-readable storage medium.

[0005] The third object of the present invention is to provide an energy storage controller.

[0006] A fourth objective of the present invention is to provide an energy storage system.

[0007] To achieve the above-mentioned purpose, a first embodiment of the present invention proposes a discharge control method for an energy storage system, wherein the energy storage system includes multiple battery packs connected in parallel, and the method includes: when it is determined that the energy storage system has not reached a preset discharge cut-off condition, obtaining the actual discharge current of each battery pack; when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, updating the current discharge current limit of the energy storage system to the sum of the actual discharge currents of the multiple battery packs, and gradually reducing the current discharge current limit of the energy storage system; in the process of gradually reducing the current discharge current limit of the energy storage system, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, then taking the sum of the actual discharge current of each battery pack as the current discharge current limit of the energy storage system.

[0008] According to the discharge control method of the energy storage system of the embodiment of the present invention, when the energy storage system does not reach the preset discharge cut-off condition, the actual discharge current of each battery pack is obtained, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and the current discharge current limit of the energy storage system is controlled to be gradually reduced. In this process, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge current of each battery pack at this time, thereby avoiding the problem that the system cannot provide sufficient discharge power due to the system discharge current being set too low, and improving the discharge capacity of the energy storage system.

[0009] In addition, the discharge control method of the energy storage system according to the above embodiment of the present invention may also have the following additional features:

[0010] According to one embodiment of the present invention, determining that the energy storage system has not reached a preset discharge cut-off condition includes: obtaining a discharge voltage of the energy storage system; and determining that the energy storage system has not reached the preset discharge cut-off condition when the discharge voltage is greater than or equal to a preset discharge cut-off voltage.

[0011] According to an embodiment of the present invention, before determining that the energy storage system has not reached a preset discharge cut-off condition, the method further includes: updating a discharge limit current corresponding to each battery pack according to an actual condition of each battery pack.

[0012] According to one embodiment of the present invention, before updating the current discharge current limit of the energy storage system to the sum of the actual discharge currents of multiple battery packs, the method also includes: when the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, returning to continue to determine whether the energy storage system reaches a preset discharge cutoff condition.

[0013] According to one embodiment of the present invention, during the process of gradually reducing the current discharge current limit of the energy storage system, if the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system continues to be controlled to be reduced.

[0014] To achieve the above objectives, a second aspect of the present invention provides a computer-readable storage medium on which a discharge control program for an energy storage system is stored. When the discharge control program for the energy storage system is executed by a processor, the discharge control method for the energy storage system described in the above embodiment is implemented.

[0015] According to the computer-readable storage medium of an embodiment of the present invention, when the discharge control program of the energy storage system stored in the storage medium is executed by the processor, by executing the discharge control program of the energy storage system, the problem of the system being unable to provide sufficient discharge power due to the system discharge current being set too low can be avoided, thereby improving the discharge capacity of the energy storage system.

[0016] To achieve the above-mentioned purpose, the third aspect of the present invention proposes an energy storage controller, which includes a memory, a processor, and a discharge control program of the energy storage system stored in the memory and executable on the processor. When the processor executes the discharge control program of the energy storage system, the discharge control method of the energy storage system described in the first aspect of the present invention is implemented.

[0017] According to the energy storage controller of an embodiment of the present invention, when the discharge control program of the stored energy storage system is executed by the processor, by executing the discharge control program of the energy storage system, the problem of the system being unable to provide sufficient discharge power due to the system discharge current being set too low can be avoided, thereby improving the discharge capacity of the energy storage system.

[0018] To achieve the above-mentioned purpose, a fourth aspect of the present invention proposes an energy storage system, which includes multiple battery packs connected in parallel; a current detection module, used to detect the actual discharge current of each battery pack; an energy storage controller, used to judge the actual discharge current of each battery pack when it is determined that the energy storage system has not reached a preset discharge cut-off condition, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, update the current discharge current limit of the energy storage system to the sum of the actual discharge currents of the multiple battery packs, and gradually reduce the current discharge current limit of the energy storage system until the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, and the sum of the actual discharge current of each battery pack is used as the current discharge current limit of the energy storage system.

[0019] According to the energy storage system of the embodiment of the present invention, the actual discharge current of each battery pack is detected by the current detection module, and the actual discharge current of each battery pack is judged by the energy storage controller when it is determined that the energy storage system has not reached the preset discharge cut-off condition, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and then the current discharge current limit of the energy storage system is gradually reduced until the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, and the sum of the actual discharge current of each battery pack is used as the current discharge current limit of the energy storage system. In this way, the problem that the system cannot provide sufficient discharge power due to the system discharge current being set too low can be avoided, and the discharge capacity of the energy storage system is improved.

[0020] According to one embodiment of the present invention, the energy storage controller is further used to obtain a discharge voltage of the energy storage system, and when the discharge voltage is greater than or equal to a preset discharge cut-off voltage, determine that the energy storage system has not reached a preset discharge cut-off condition.

[0021] According to one embodiment of the present invention, the energy storage controller is further used to update the discharge limit current corresponding to each battery pack according to the actual situation of each battery pack before determining that the energy storage system has not reached a preset discharge cut-off condition.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a flow chart of a discharge control method for an energy storage system according to an embodiment of the present invention;

[0024] Figure 2 is a flow chart of a discharge control method for an energy storage system according to a specific embodiment of the present invention;

[0025] Figure 3 A block diagram of an energy storage controller according to an embodiment of the present invention;

[0026] Figure 4 FIG. 4 is a block diagram of an energy storage system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] Embodiments of the present invention are described in detail below, examples of which 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 intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0028] It should be noted that the energy storage system proposed in the embodiment of the present invention includes multiple battery packs, a voltage detection module, a current detection module and an energy storage controller. Among them, the multiple battery packs are connected in parallel, and the actual discharge current of the corresponding energy storage system is the sum of the actual discharge currents of the multiple battery packs.

[0029] Figure 1 FIG. 1 is a flow chart of a discharge control method for an energy storage system according to an embodiment of the present invention. Figure 1 As shown, the discharge control method of the energy storage system includes the following steps:

[0030] Step S1, when it is determined that the energy storage system has not reached a preset discharge cut-off condition, the actual discharge current of each battery pack is obtained.

[0031] Specifically, the discharge voltage of the energy storage system can be obtained by a voltage detection module (such as a voltage sensor), and the discharge voltage of the energy storage system is sent to the energy storage controller. The energy storage controller determines whether the energy storage system has reached a preset discharge condition based on the discharge voltage, wherein when the discharge voltage is greater than or equal to a preset discharge cut-off voltage, it is determined that the energy storage system has not reached the preset discharge cut-off condition; when the discharge voltage is less than the preset discharge cut-off voltage, it is determined that the energy storage system has reached the preset discharge cut-off condition. It should be noted that the preset discharge cut-off voltage can be set according to actual conditions.

[0032] The actual discharge current of each battery pack may be detected by a current detection module (such as a current sensor), and the actual discharge current of each battery pack may be sent to the energy storage controller.

[0033] Step S2, when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of the multiple battery packs, and the current discharge current limit of the energy storage system is gradually reduced.

[0034] Specifically, after obtaining the actual discharge current of each battery pack, the energy storage controller compares the actual discharge current of each battery pack with its corresponding current discharge limit current. When the actual discharge current of any battery pack is greater than the corresponding current discharge limit current, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and the current discharge current limit of the energy storage system is gradually reduced at a rate of △I / s (the current limit decreases by △I per second s) to enable the battery pack with a larger discharge current to be fully discharged as much as possible, thereby improving the discharge power of the energy storage system and improving the discharge capacity. It should be noted that the rate △I / s can be set according to actual conditions.

[0035] In some embodiments of the present invention, before updating the current discharge current limit of the energy storage system to the sum of the actual discharge currents of multiple battery packs, the above-mentioned discharge control method of the energy storage system also includes: when the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, returning to continue to determine whether the energy storage system reaches a preset discharge cut-off condition.

[0036] That is to say, when there is no battery pack whose actual discharge current is greater than the corresponding current discharge limit current, it means that there is no battery pack with a larger discharge current. At this time, the current discharge current limit is kept unchanged, and discharge is continued, and it is determined whether the energy storage system reaches the preset discharge cut-off condition.

[0037] Step S3, during the process of gradually decreasing the current discharge current limit of the energy storage system, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, the sum of the actual discharge current of each battery pack is used as the current discharge current limit of the energy storage system.

[0038] Specifically, during the process of reducing the current discharge current limit of the energy storage system, if the energy storage controller detects that the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, it means that there is no battery pack with a large discharge current. At this time, the current discharge current limit of the energy storage system is re-updated to the sum of the actual discharge currents of each battery pack, and discharge continues based on the discharge current limit, and it is judged whether the energy storage system reaches the preset discharge cut-off condition. If it has been reached, the discharge is stopped, otherwise steps S1-S3 are repeated until the energy storage system reaches the preset discharge cut-off condition and stops discharging; if the energy storage controller still detects that the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system continues to be controlled to be reduced, that is, the current discharge current limit of the energy storage system continues to be reduced at a rate of △I / s.

[0039] In the above embodiment, when the energy storage system does not reach the preset discharge cut-off condition, the actual discharge current of each battery pack is obtained, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and the current discharge current limit of the energy storage system is gradually reduced until the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, so that the battery pack with a larger discharge current can be fully discharged, thereby improving the discharge power of the system, avoiding the problem that the system cannot provide sufficient discharge power due to the system discharge current being set too low, and improving the discharge capacity of the energy storage system.

[0040] Optionally, in some embodiments of the present invention, before determining that the energy storage system has not reached a preset discharge cut-off condition, the above-mentioned discharge control method of the energy storage system further includes: updating the discharge limit current corresponding to each battery pack according to the actual situation of each battery pack.

[0041] Specifically, when the energy storage controller determines that the energy storage system has not reached a preset discharge cut-off voltage based on the discharge voltage of the energy storage system, the energy storage controller also updates the discharge limit current corresponding to each battery pack based on the actual situation of each battery pack to avoid over-discharge of the battery pack. For example, the current discharge limit current of the battery pack can be determined based on the SOC (State Of Charge) of the battery pack, wherein the larger the SOC of the battery pack, the stronger the discharge capacity, and the larger the discharge limit current of the battery pack.

[0042] Therefore, during the discharge process, over-discharge of the battery pack can be avoided by updating the discharge limit current of the battery pack according to the actual situation of the battery pack. Then, updating the discharge current limit of the energy storage system based on the real-time updated discharge limit current and the actual discharge current of the battery pack can enable each battery pack to be fully discharged while avoiding over-discharge of the battery pack, thereby improving the discharge power of the energy storage system.

[0043] In order to enable those skilled in the art to more clearly understand the present application, as a specific example, refer to Figure 2 As shown, the discharge control method of the energy storage system includes the following steps:

[0044] Step S21, the energy storage system starts discharging.

[0045] Step S22, update the discharge limit current corresponding to each battery pack according to the actual situation of each battery pack (for example, SOC). It should be noted that the discharge limit current of each battery pack is updated in real time, that is, updated in real time during the entire discharge process to avoid over-discharge of the battery pack.

[0046] Step S23, determine whether the discharge cut-off condition is met. If yes, execute step S30; otherwise, execute step S24.

[0047] Step S24, obtaining the actual discharge current of each battery pack.

[0048] Step S25, determining whether the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current. If yes, return to step S23; otherwise, execute step S26.

[0049] Step S26, updating the current discharge current limit of the energy storage system to the sum of the actual discharge currents of the multiple battery packs, so as to fully discharge the battery packs with larger discharge currents as much as possible and improve the discharge power.

[0050] Step S27, the current discharge current limit of the energy storage system is controlled to be gradually reduced at a certain rate (△I / S), that is, the current discharge current limit of the energy storage system is gradually reduced as the battery pack continues to discharge.

[0051] Step S28, determining whether the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current. If so, executing step S29; otherwise, returning to step S27.

[0052] In step S29, the sum of the actual discharge currents of each battery pack is used as the current discharge current limit of the energy storage system, and the process returns to step S23. That is, after a period of full discharge of the battery pack with a larger discharge current, its actual discharge current will be lower than the corresponding current discharge limit current. At this time, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of each battery pack, and then the discharge continues. Since the discharge limit current of the battery pack is updated in real time, it is still possible that the actual discharge current of the battery pack is greater than the corresponding discharge limit current. If the actual discharge current of any battery pack is greater than the corresponding discharge limit current again, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of each battery pack. The discharge continues in this manner until the discharge cut-off condition is reached. Thus, during the discharge process, by continuously adjusting the discharge limit current of each battery pack and the discharge current limit of the energy storage system, each battery pack can be fully discharged while avoiding over-discharge of the battery pack.

[0053] Step S30: the energy storage system discharges completely.

[0054] In summary, according to the discharge control method of the energy storage system of the embodiment of the present invention, when the energy storage system does not reach the preset discharge cut-off condition, the actual discharge current of each battery pack is obtained, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and the current discharge current limit is controlled to be gradually reduced. In this process, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge current of each battery pack at this time, thereby avoiding the problems of over-discharge and insufficient discharge power of the battery packs in the energy storage system and improving the discharge capacity of the energy storage system.

[0055] Corresponding to the above embodiment, an embodiment of the present invention further proposes a computer-readable storage medium on which a discharge control program of an energy storage system is stored. When the discharge control program of the energy storage system is executed by a processor, the discharge control method of the energy storage system described in the above embodiment is implemented.

[0056] According to the computer-readable storage medium of an embodiment of the present invention, when the discharge control program of the energy storage system stored in the storage medium is executed by the processor, by executing the discharge control program of the energy storage system, the problems of over-discharge and insufficient discharge power of the battery pack in the energy storage system are avoided, and the discharge capacity of the energy storage system is improved.

[0057] Corresponding to the above embodiment, the embodiment of the present invention further proposes an energy storage controller. Figure 3As shown, the controller 30 includes a memory 310, a processor 320, and a discharge control program of the energy storage system stored in the memory and executable on the processor. When the processor 320 executes the discharge control program of the energy storage system, the discharge control method of the energy storage system described in the first aspect of the embodiment is implemented.

[0058] According to the energy storage controller of an embodiment of the present invention, when the discharge control program of the stored energy storage system is executed by the processor, by executing the discharge control program of the energy storage system, the problems of over-discharge and insufficient discharge power of the battery pack in the energy storage system are avoided, thereby improving the discharge capacity of the energy storage system.

[0059] Corresponding to the above embodiment, the embodiment of the present invention further proposes an energy storage system. Figure 4 As shown, the energy storage system 40 includes a plurality of battery packs 410 , a current detection module 420 and an energy storage controller 430 .

[0060] Among them, multiple battery packs 410 are connected in parallel; the current detection module 420 is used to detect the actual discharge current of each battery pack 410; the energy storage controller 430 is used to judge the actual discharge current of each battery pack 410 when it is determined that the energy storage system 40 has not reached the preset discharge cut-off condition, and when the actual discharge current of any battery pack 410 is greater than the current discharge limit current of the battery pack 410, the current discharge current limit of the energy storage system 40 is updated to the sum of the actual discharge currents of the multiple battery packs 410, and the current discharge current limit of the energy storage system 40 is gradually reduced and controlled until the actual discharge current of each battery pack 410 is less than or equal to the corresponding current discharge limit current, and the sum of the actual discharge currents of each battery pack 410 is used as the current discharge current limit of the energy storage system 40.

[0061] In some embodiments of the present invention, the energy storage controller 430 is further used to obtain a discharge voltage of the energy storage system 40, and when the discharge voltage is greater than or equal to a preset discharge cut-off voltage, determine that the energy storage system 40 does not reach a preset discharge cut-off condition.

[0062] In some embodiments of the present invention, the energy storage controller 430 is also used to update the discharge limit current corresponding to each battery pack 410 according to the actual situation of each battery pack 410 before determining that the energy storage system 40 has not reached the preset discharge cut-off condition.

[0063] In some embodiments of the present invention, the energy storage controller 430 is further used to obtain a discharge voltage of the energy storage system 40; when the discharge voltage is greater than or equal to a preset discharge cut-off voltage, it is determined that the energy storage system 40 has not reached a preset discharge cut-off condition.

[0064] In some embodiments of the present invention, the energy storage controller 430 is also used to continue to determine whether the energy storage system 40 has reached a preset discharge cutoff condition when the actual discharge current of each battery pack 410 is less than or equal to the corresponding current discharge limit current before updating the current discharge current limit of the energy storage system 40 to the sum of the actual discharge currents of the multiple battery packs 410.

[0065] According to one embodiment of the present invention, the energy storage controller 430 is also used to continue to control the reduction of the current discharge current limit of the energy storage system 40 if the actual discharge current of any battery pack 410 is greater than the current discharge limit current of the battery pack 410 during the process of gradually reducing the current discharge current limit of the energy storage system 40.

[0066] It should be noted that, for the description of the energy storage system, please refer to the aforementioned description of the discharge control method of the energy storage system, which will not be described in detail here.

[0067] According to the energy storage system of the embodiment of the present invention, the actual discharge current of each battery pack is detected by the current detection module, and the actual discharge current of each battery pack is judged by the energy storage controller when it is determined that the energy storage system has not reached the preset discharge cut-off condition, and when the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of multiple battery packs, and then the current discharge current limit of the energy storage system is gradually reduced until the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, and the sum of the actual discharge current of each battery pack is used as the current discharge current limit of the energy storage system. In this way, the problems of over-discharge and insufficient discharge power of the battery pack in the energy storage system are avoided, and the discharge capacity of the energy storage system is improved.

[0068] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0069] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0070] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does 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.

[0071] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0072] In addition, the terms "first", "second", etc. used in the embodiments of the present invention are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the present embodiment. Therefore, the features defined by the terms "first", "second", etc. in the embodiments of the present invention can explicitly or implicitly indicate that the embodiment includes at least one of the features. In the description of the present invention, the word "multiple" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0073] In the present invention, unless otherwise clearly specified or limited in the embodiments, the terms "installed", "connected", "connected" and "fixed" etc. in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integrated connection. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements, or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific implementation situation.

[0074] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0075] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A discharge control method for an energy storage system, characterized in that: The energy storage system includes a plurality of battery packs connected in parallel, and the method includes: When it is determined that the energy storage system has not reached a preset discharge cut-off condition, obtaining an actual discharge current of each of the battery packs; When the actual discharge current of any one of the battery packs is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system is updated to the sum of the actual discharge currents of the plurality of battery packs, and the current discharge current limit of the energy storage system is gradually reduced; During the process of gradually decreasing the current discharge current limit of the energy storage system, if the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, the sum of the actual discharge current of each battery pack is used as the current discharge current limit of the energy storage system.

2. The discharge control method of the energy storage system according to claim 1, characterized in that: Determining that the energy storage system has not reached a preset discharge cut-off condition includes: Obtaining a discharge voltage of the energy storage system; When the discharge voltage is greater than or equal to a preset discharge cut-off voltage, it is determined that the energy storage system has not reached a preset discharge cut-off condition.

3. The discharge control method of the energy storage system according to claim 1, characterized in that: Before determining that the energy storage system has not reached a preset discharge cut-off condition, the method further includes: The discharge limit current corresponding to each battery pack is updated according to the actual situation of each battery pack.

4. The discharge control method of the energy storage system according to any one of claims 1 to 3, characterized in that: Before updating the current discharge current limit of the energy storage system to the sum of actual discharge currents of the plurality of battery packs, the method further includes: When the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, the process returns to continue determining whether the energy storage system reaches a preset discharge cut-off condition.

5. The discharge control method of the energy storage system according to any one of claims 1 to 3, characterized in that: During the process of gradually reducing the current discharge current limit of the energy storage system, if the actual discharge current of any battery pack is greater than the current discharge limit current of the battery pack, the current discharge current limit of the energy storage system continues to be controlled to be reduced.

6. A computer-readable storage medium, characterized in that: A discharge control program of an energy storage system is stored thereon, and when the discharge control program of the energy storage system is executed by a processor, a discharge control method of an energy storage system according to any one of claims 1-5 is implemented.

7. An energy storage controller, characterized in that: The invention comprises a memory, a processor and a discharge control program of an energy storage system which is stored in the memory and can be run on the processor. When the processor executes the discharge control program of the energy storage system, the discharge control method of the energy storage system according to any one of claims 1 to 5 is implemented.

8. An energy storage system, characterized in that: include: A plurality of battery packs, wherein the plurality of battery packs are connected in parallel; A current detection module, used to detect the actual discharge current of each battery pack; The energy storage controller is used to judge the actual discharge current of each of the battery packs when it is determined that the energy storage system has not reached a preset discharge cut-off condition, and when the actual discharge current of any of the battery packs is greater than the current discharge limit current of the battery pack, update the current discharge current limit of the energy storage system to the sum of the actual discharge currents of the multiple battery packs, and gradually reduce the current discharge current limit of the energy storage system until the actual discharge current of each battery pack is less than or equal to the corresponding current discharge limit current, and then use the sum of the actual discharge current of each battery pack as the current discharge current limit of the energy storage system.

9. The energy storage system according to claim 8, characterized in that: The energy storage controller is further used to obtain a discharge voltage of the energy storage system, and when the discharge voltage is greater than or equal to a preset discharge cut-off voltage, determine that the energy storage system has not reached a preset discharge cut-off condition.

10. The energy storage system according to claim 8 or 9, characterized in that: The energy storage controller is also used to update the discharge limit current corresponding to each battery pack according to the actual situation of each battery pack before determining that the energy storage system has not reached a preset discharge cut-off condition.

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